Horticulture

While the negative impacts of drought are often disproportionately spread to low-income individuals, we have seen that windfall gains to agriculture create short-run spillovers to other industries . This spillover is likely to impact closely related industries in terms of input-output and exchange the most . In the case of agriculture, we understand this to be industries that directly rely on agricultural output such as food manufacturing and wholesale. When we consider the spillover impacts of a crisis event such as drought, there is evidence that the volatility of agricultural input exerts significant spillover effects on the volatility of agricultural output and retail food prices . I treat drought as a crisis event that creates volatility in the agricultural input price of water. Hornbeck and Keskin found that windfall gains to the agricultural industry can create short run spillover to other local industries. While they found no evidence of long-run sustained spillover, as my data does not include ex-post results, this does not pose a threat to the scope of my study. In general,vertical plant tower spillover is likely to be strongest in closely related industries and exert significant impact in times of crisis or in instances of volatile input prices.

I observe the crisis period of the 2012 to 2016 California drought and the volatility it created in agricultural input and outputs to evaluate how drought impacts local incomes and employment. To the best of my knowledge, this is the first study utilizing individual data to analyze possible spillover impacts of the 2012 to 2016 California drought.3 Previous studies focus on statewide impacts of the recent California drought or analyze different aspects of labor market impacts for either this or other historical droughts. Literature suggests that I would identify a significant negative impact on the agricultural industry and closely related industries during this time period.I estimate a difference in difference regression comparing outcomes in San Joaquin and Tulare, the two counties that experienced 90% of farmland fallowing, with outcomes in similar Central Valley counties. I find a significant 9% reduction in employment and an 11% reduction in individual income for those working in agriculture.4 Although I expected to discover contractions in closely related industries, I observe almost no impact on these industries’ employment and incomes. There were also no significant differences in the impact of the drought between males and females when my regression was run with a gender interaction. However, an additional interaction shows a significant and highly negative impact on Hispanic individual employment in agriculture by 12% and further reduction in wages by 13%.

This signals that although the economy was resilient, the drought disproportionately impacted Hispanic agricultural workers. Additionally, the small spillovers that occurred into related industries had impact only on Hispanic workers. This result represents a departure from traditional intuition that observes spillover between closely related industries, particularly during a crisis. Although these results are unusual, further robustness checks and a statistically optimized control group would be necessary to confirm the lack of spillover effects. This instance of limited spillover could reflect the recent popularization of water permit trading amongst farmers and the introduction of new drought-related welfare programs . Data on water trading rates and prices are not currently aggregated or publicly available but would be an area for potential further study. Prior research finds that water management policy coordinated with farmers has the potential to increase environmental and economic gains to all parties . A detailed input-output study would also further improve the validity of my results. These models are commonly used to analyze changes in farmer behavior in reaction to price changes among other purposes and could be fit to the scenario of a drought .Lund et al. synthesize their past research on drought with contributions from other prominent researchers in the field to create a full picture of the impact in “Lessons from California’s 2012-2016 Drought”. I draw from components focusing on employment and revenue losses.

In their preliminary findings, agriculture was the industry primarily impacted through increased pumping costs of $600 million per year and half a million acres of fallowed crop area. When water supplies reached a low in 2012 to 2015, certain negotiated contracts with water projects received zero deliveries. Lund et al. touch on the uncertainty for future strength during drought caused by overdraft of groundwater, first reported by MacEwan et al. This will most likely hit rural areas the hardest as they have the least access to water and lower aquifer elevations available for groundwater pumping. The paper finds that overall resilience was due to strong prices for key specialty crops, ability to rely on groundwater, effective water management, and the beginnings of a robust water trading market. Despite this, they acknowledge that these costs were likely concentrated in areas with a lack of easily accessible groundwater. There is no detailed analysis of county level impacts on these rural and dry counties in the San Joaquin Valley and Tulare River Basin due to the 2012 to 2016 drought. Cooley et al. similarly find that overall impacts were mitigated, but discuss the need for local variability estimates for areas that experienced intense fallowing. Related literature has indeed shown that rural and low-income individuals have less tolerance for natural disasters. A drought of a similarly intense magnitude occurred in Australia from 2001 to 2004. Carroll et al. used life satisfaction survey data to estimate that the occurrence of the drought was equivalent to an annual reduction in income of $18,000 . Using fixed effects to control for unobserved area characteristics, this impact appeared only for individuals living in rural areas. While the Australian economy suffered more heavily due to a lack of drought infrastructure, the divide between rural and urban individuals in this case is clear. I use a similar regression with fixed effects and demographic controls to look at labor market outcomes for the California Drought from 2012 to 2016. As with the Australian drought, this recent California drought has been proven to be hydrologically severe and sustained marked losses within the agricultural sector . Following the focus on rural and low-income individuals I estimate differences between the hydrologically dry rural counties with counties that were able to mitigate most drought losses with groundwater and water project contracts. Based on further studies I determine that San Joaquin and Tulare counties were the most heavily impacted during this time period and faced the heaviest groundwater pumping costs. My study differs in its approach,10 liter drainage collection pot data and focus. I choose to use survey data and look at individual characteristics within the more closely focused county groups. Additionally, I test for differences in outcomes for Hispanic individuals and females. The 2012 to 2016 California drought was found to create emotional distress regarding food insecurity, particularly in Hispanic households . My results and analysis provide further evidence of the harsher penalties imposed on rural and Hispanic agricultural households due to drought conditions.I additionally confirm the question theorized by earlier research in this field that there indeed was variability in county level impact due to the drought.“Does Agriculture Generate Local Economic Spillovers? Short-Run and Long-Run Evidence from the Ogallala Aquifer” by Hornbeck and Keskin is the most closely related and influential paper in the design and understanding of my topic.

This paper analyzes the impact of new technology that allowed farmers to utilize a new groundwater source, the Ogallala Aquifer. This windfall gain to the agricultural sector allows Hornbeck and Keskin to estimate the differences between counties with a high proportion of areas with increased water access and those that largely missed the benefits of this new water source. They estimate a difference in difference regression controlling for various agricultural effects and time effects to estimate the spillover impact of increased water access. They find that areas with high exposure to the Ogallala had increased agricultural gains through land value and revenue. This also caused an exogenous increase in rural farm employment. Similar to my paper, they set manufacturing, wholesale, retail, and services as comparison industries for their economic closeness. While this did not extend to the long-run, Hornbeck and Keskin did find short-run statistically significant expansions in these industries. While this result is different from the lack of spillover seen in my results, I attribute this limit of negative spillover to efficient water management and programs to limit contractions to the agricultural industry itself. Notably, Moretti demonstrated that spillovers occur between closely related industries with greater frequency and intensity than in industries that are distant. Instead of focusing on measures of agricultural workers or rural areas, Moretti looks to the proportion of college-educated workers within a data set cataloging production plant productivity. He finds an increase in plant productivity as a result of the faster growth of the proportion of college-educated workers in an area. This effect is larger for economically close industries, reflecting the spillover of knowledge and physical capital accumulation. Additionally, Kang et al. find that there is a strong impact of spillover during and after the crisis period by estimating commodity futures returns. This reflects a premium on uncertainty and increased supply chain costs for closely related industries that rely on crude commodities. We would expect to see the greatest impact on industries purchasing and relying on outputs of the agricultural sector . My findings that closely related sectors were not impacted is a departure from this intuition and is reflective of the effective water management and drought mitigation techniques that contained heavy losses to parts of the agricultural industry while keeping agricultural produce prices stable. Nazlioglu et al. find that after the occurrence of a crisis in oil markets there is significant market volatility on key agricultural commodities. Using a GARCH model they show that there is a growing linkage between agriculture and energy markets due to their similarities and investor profile. Further work done by Apergis and Rezitis delves further into the links between agricultural input prices and output commodities. They used agricultural commodity prices in Greece from 1985 to 1990 to test for links in equilibrium price patterns. The study finds that there are significant linkages in price variation between agricultural input and output prices, and between agricultural output prices and retail food output prices. They also find evidence of imperfect price transmission among the three categories so that exogenous shocks would create disparate welfare changes among market participants. Since output prices were observed to be more flexible than input and retail prices, this indicates that general price decreases in a crisis would create short term losses for farmers as their prices decrease faster than input prices. This aligns with my findings that agricultural earnings had large short-run decreases due to drought-related shocks. The main purpose of this study is to quantify how economic spillovers between industries impacted individuals living in areas severely affected by the 2012 to 2016 drought. I chose to use U.S. government survey data to have access to one of the largest data sources on my target counties while retaining other significant data measures on the socio-economic profile of the individuals. The American Community Survey collects cross-sectional data on individuals with attached characteristics and publishes annually to the Integrated Public Use Microdata Series . The ACS uses a series of monthly samples on 250,000 addresses to produce an annual estimate of data for the same small areas on 3,000,000 addresses. My data extract is limited to individuals in the California Central Valley in the years 2006 to 2017 for sample size consistency. I use the California Research Bureau classification of the 18 Central Valley counties.To ensure the accuracy of my results I used the IPUMS provided CPI adjustment factor to convert income to 2005 dollars, so estimates are standardized to the beginning of the observed time period. Additionally, only individuals in the age range of 20 to 65 that did not reside in group quarters were kept, to ensure individuals not typically in the labor market did not distort income estimates. Before performing analysis, observations with missing values for labor industry classification or income were removed. After these modifications, the data includes 435,996 individual observations on individuals living in counties categorized as the Central Valley. I used sex, educational attainment, and race control variables to add accuracy to the estimate without over fitting my model.6

We expand on this prior work on infectious disease by testing whether this distinction might also be important for explaining common mental illness – a fundamental aspect of health that has been extensively demonstrated to show significant associations with poverty. The picture from decades of research from high-income countries is clear: worse socioeconomic status consistently predicts worse mental health outcomes, especially common mental disorders like anxiety and depression . The associations do not solely mean that conditions of poverty drives common mental disorders , but may also often feed each other syndemically in a “vicious cycle” . In higher income countries the onset, deterioration or relapse of mental illness in turn tends to increase economic risk and undermine wealth . The uncertainty of living with material poverty in itself is proposed to be stressful in ways that can trigger or heighten mental distress . This is explained in part by both poverty and female gender intersecting with many other related vulnerabilities – like under nutrition, low education, poor access to health services, chronic physical illness, gender-based violence and discrimination,vertical agriculture stigma/discrimination, or other forms of low social capital – that can heighten risks further .

In contrast, emerging research in low- and middle-income countries paints a more complex picture. Specifically, measures of material poverty, such as financial stress, food insecurity, income, and consumption expenditures, have shown surprisingly mixed associations with mental health in LMIC contexts . Of these, food insecurity tends to demonstrate the more robust associations ; income and expenditure less so . A number of reasons have been proposed for these inconsistent findings, including measurement issues and the argument that the everyday contexts and stressors of poverty are fundamentally different between higher and lower income countries in ways that matter for mental health .A commonly applied measure of wealth/poverty in research in LMICs is the Demographic and Health Survey wealth index. This indicator is mainly based on household assets that can be purchased in the cash economy . Using a statistical reduction technique, household items , quality of housing construction , and access to services are scaled into a single one dimensional index. This asset-based indicator has become the key variable used in LMICs to assess economic gradients in education , nutrition , physical health , mortality , and mental health . However, this uni-dimensional index really only captures household poverty through livelihoods associated with the cash economy . Importantly, too, these cash-economic goods or services are more easily accessible in urban areas; thus, they often depict rural settings as largely poor or deprived .

In countries or regions where agriculture plays a dominant role in many household economies, agricultural assets should fundamentally shape experiences of poverty. Most notably, availability of crops and animals for household consumption provides food security. Agricultural assets are also means of production and can contribute to the household income . Importantly, too, agricultural assets need not be held solely by, or provide benefit to, rural households. Peri-urban and even urban households owning even just a few animals or small plots of cultivatable land can produce small but valuable amounts of consumable or sellable food . For these reasons, agricultural wealth could provide a straightforward buffer against nutrition-related disease at the very least . Beyond such effects on nutrition and wealth, agricultural assets might also enhance social capital and status to provide further buffering effects for mental health. For example, in a Tanzanian community in which cattle ownership is prestigious, lack of ownership was found to predict mental distress: being without cattle meant one really could not belong in a society that viewed themselves as defined by their pastoralism and relationship to cows . In a study of livestock and animal assets in DRC, Glass et al. computed a total livestock asset score for rural women, finding that animal ownership had a moderating effect on depression symptoms. They proposed that ownership provided means to produce cash that could pay school fees, purchase land, and get materials to build/repair homes, but it was also potentially buffering via the social indexing of women’s productivity and status .

Similarly, cultivatable land ownership does not just reflect material wealth but also in some contexts lends the owner considerable power, status, and prestige . In spite of the potential for agricultural assets to buffer health risks, few empirical studies have considered these alternative dimensions of wealth in assessing the relationship between poverty and well being in low-income countries . Based on these multiple proposed mechanisms by which agricultural wealth might buffer vulnerabilities, we should also expect that greater household agricultural wealth could have a protective effect in relation to mental well being .Thus, in this study we consider how lack of agricultural assets – as a specific dimension of poverty – is associated with common mental disorder symptoms in Haiti. Our basic proposition is that household agricultural wealth will promote mental wellbeing – or buffer against depression and anxiety symptoms – with an effect evident beyond other commonly measured forms of material wealth, such as cash-economy wealth and food security. We analyze novel data from Haiti, considering how these relate within geographically randomly selected samples from three very different, but all highly vulnerable, communities. These contrast with each other in degree of rurality and direct access to and dependence on agricultural assets – a fully urban neighborhood, a fully rural zone, and a mid-sized town with a rural hinterland. Due largely to a complex history of foreign intervention, Haiti is the poorest nation in the Western hemisphere and one of the most economically unequal in the world, with high national dependence on the agricultural sector . Much of the rural farming is done on small plots by smallholder farmers, but making a living with small-scale farming is increasingly difficult given poor quality and lack of land, complex legal issues around proving land ownership, and vulnerabilities to natural hazards . These peyizan often balance multiple informal occupations; moreover, they can inhabit peri-urban and suburban zones, though most live in rural areas . The study communities reflect three particularly vulnerable sites within Haiti,vertical farming aeroponics all with high levels of food insecurity and significant material poverty . However, they differ substantially in agricultural wealth.

Martissant is a fully urban, densely-populated district of the City of Port-au-Prince where a minority of households surveyed own cultivatable land or animals . Ouanaminthe is a market border town with rural hinterland located across the Massacre River from the Dominican Republic, exhibiting a mix of subsistence and cash economy households ; Cornillon is a fully rural community in the West department with much higher rates of household cultivatable land and animal ownership . Additionally, both Ouanaminthe and Cornillon are municipalities, called Commune in Haiti, and have their own local administrative authority, an elected three-member mayoral council; while Martissant is a municipal district administrated by the City of Port-au-Prince . We surveyed 4055 households . Household sampling was powered so that each site would be able to detect an effect size of 0.15. The survey used a two-stage cluster sampling approach to select households. In the first stage, using the smallest census territorial entity called Dissemination Areas , all three sites under study were divided into clusters determined by the level of access to core services and central markets located in the main town or village. The level of access was measured based on two criteria, having an all season road and the distance from each DA to reach those core services. Four clusters were generated: accessibility very difficult, accessibility difficult, accessible, and very accessible. On the basis of probability proportional to size, a random sample of DAs was selected in each cluster for a total of 157 of 389 DAs in all three sites. Then, 25-26 households within each selected DA were selected in randomly generated sequence, while also allowing for over-selection of female household heads if needed to meet a 45% goal . The questionnaire was administrated in-person to the head of the selected households . Table 1 summarizes variables included in our analyses. We assessed mental well-being with locally adapted and/or validated depression and anxiety inventories. The Zanmi Lasante Depression Symptom Inventory assesses a combination of culturally adapted items from standard depression screeners and local idioms of distress . The ZLDSI was completed among a sample of 105 patients who also underwent diagnostic assessment by Haitian psychologists and social workers. Results were used to clinically validate the tool and identify cut-off scores for depression. The ZLDSI contains 13 symptom items, which respondents’ rate using a Likert scale from not at all to almost every day , based on frequency they occurred within the last 15 days. These were summed to provide total scores ranging from 0 to 39.

The Beck Anxiety Inventory was culturally adapted in a previous study in rural Haiti . Bilingual individuals provided initial translations of items, which were then discussed in focus groups. Participants commented on comprehensibility, acceptability, and relevance of each item, as well as recommending alternate wording. The Kreyòl BAI assesses experience of 20 anxiety symptom over the previous two weeks . Each question is scored from not at all to severe , yielding a possible range from 0 to 60. Our estimations of household wealth used a multidimensional approach . We included a wide range of household assets, household construction materials, access to basic services, and agricultural assets. Questions included vehicles and consumer goods; wall, roof and floor material; electrical access, sources of drinking water, toilet type; and ownership of livestock and land. All wealth related items were dummy coded . Those with more than two categories were recoded as a series of dummy variables. Count variables such number of livestock were ranged into categorical brackets before coding as dummy series . To derive wealth dimensions that are comparable with nationally representative surveys, we matched asset variables from the current survey to the Haiti Demographic and Health Survey and applied multiple correspondence analysis to the Haiti DHS household-by-variable matrix . These analyses identified two reliable dimensions of wealth/poverty, which accounted for 77.13% of the total dataset inertia. The first one, with 63.9% of the explained total, is strongly associated with variables such as having at least a TV, a radio, electricity, a cooker, internet services, or a bank account. We refer to this as our “cash economy wealth” measure. The second dimension is highly and clearly related to agricultural and subsistence assets, such as owning poultry or a boat , and we refer to this as our “agricultural wealth” measure. A third dimension solely related to latrine ownership and was discarded. Cronbach’s alpha showed good internal consistency for the two wealth dimensions: cash economy and agricultural . The first dimension was also highly correlated with the standard DHS wealth factor score produced using Principal Components Analysis , but the second dimension was not . This observed difference suggests that the agricultural dimension of wealth provides a distinctive means to characterize households in relation to each other. Then, using the DHS data, we estimated linear regressions predicting each of the two wealth dimensions from all asset variables in the DHS data that were also available in the current survey. This was facilitated by initial survey design aimed at maximizing overlap with DHS wealth index items, alongside additional wealth questions. Finally, we used those regression coefficients from the DHS data to estimate the two wealth dimensions for the current dataset based on each household’s assets. We also included food insecurity, water insecurity, income, financial stress, and household socio-economic status as key covariates likely highly correlated with household assets. A global analysis of over 145 countries shows household food insecurity is consistently associated with poor mental health in a dose-response pattern . While there is less direct evidence, household water scarcity also shows an association with anxiety and depression symptoms, with women most affected . To take this into account in our modeling, we applied the Household Food Insecurity Access Scale to assess household food insecurity . The HFIAS asks how often during the past two weeks was there: no food to eat of any kind in your house because of lack of resources to get food, any household member went to sleep at night hungry because there was not enough food, and if any household member spent a whole day and night without eating anything at all because there was not enough food.

During this time, there were two corresponding kinds of migration: migration by laborers and would-be landowners to existing currant-growing regions, and migration by colonists to undeveloped land and non-currant growing regions. With these two types of migration taken together, it is evident that, in the currant growing region of the Peloponnese, there was a general shift in the population from upland and mountain villages to lowland, coastal plains. Not only was the currant zone of Greece expanding to encompass more land, but more people from other parts of Greece were moving into the currant zone to settle inside. Alexis Franghiadis writes that population growth in the currant-growing parts of the Peloponnese indicates “the continuous resettlement of families from the arid and overpopulated highlands of the Peloponnese to the previously desert and marshy northern, western, and southern coastal plains.”Lowland settlement in previously uncultivated parts of the Peloponnese was achieved through a form of regional chain migration. In the first half of the nineteenth century,square plastic pot transhumant pastoralists built temporary dwellings, called exospitia, in the coastal plains of the Peloponnese.

These were not considered separate settlements at this time because they were small and temporary. Then, the intensification of currant cultivation in the nineteenth century caused these temporary settlements to spread and expand. In census records, some of them began to be designated as the “winter capital” of their respective municipalities, with the older, upland settlements designated as the “summer capital.” Toward the end of the century, as currant cultivation continued to spread due to increased global demand, these temporary settlements grew into permanent settlements in their own right. Pastures disappeared from the coasts as they were replaced by vineyards, and transhumant pastoralism declined in the region as it was replaced by permanent lowland settlement.The lowland plains of the coastal Peloponnese were colonized through this process. This transformative process had a greater effect in parts of the peninsula where currant cultivation was not already strong. This can be seen by comparing municipalities along the northern coast of the Peloponnese. In some of these places, especially in the hinterlands of the currant-exporting port cities, currant cultivation was already strong in the eighteenth century. In others, currant cultivation was not prevalent until the second half of the nineteenth century. Aigialeia, in the North Peloponnese, was well-populated at the beginning of the nineteenth century, and lowland settlement was already present.

Its capital, Aigio , was part of the traditional currant-growing core and was thought to produce the highest quality currants. Looking at population movement from 1879 to 1896, the trend is one of general demographic growth in the hills as well as in the coastal plain. The capital, Aigio, is the largest settlement during this period and also grows the most. Yet new settlements emerge on hills and plains alike, and they all seem to have been growing . Moving east along the northern coast of the Peloponnese, however, an examination of the same census records shows how lowland colonization advanced. An analysis of census records for the municipality of Krathis, near the middle of the Northern coast of the Peloponnese, illustrates how this worked. In the early nineteenth century, the only settlements listed in censuses for the municipality of Krathis were all located at higher elevations. A Venetian census from 1700, a French census from 1829, and a Greek census from 1836 all omitted any mention of lowland settlements in this municipality. These censuses recorded only five permanent settlements in this municipality, and all of them were located above 700 meters above sea level . Then, in the middle of the century, censuses began to list lowland settlements. A Greek census from 1845 mentioned nine settlements in this municipality: the five upland villages as well as four new settlements in the currant-growing region of the coastal plains. These new settlements, however, were not categorized as autonomous villages—they were listed as annexes of the original villages.

They were bracketed together with the older settlements, and their populations were counted together, indicating that the new lowland settlements were considered colonies of these original villages. By the end of the nineteenth century, the brackets disappeared and the new settlements each got their own line in the census, designating these as autonomous settlements.A similar pattern is visible in the deme of Voura, which neighbors Krathis to the West . The 1700 Venetian census lists four main neighborhoods located “at some distance from one another” that comprised Villa Diacoftò and its belongings . These were Chierniza, Vrostena, Piscopi, and Castro .20 In the 1879 Greek census, there were only two settlements with population counts listed in the deme of Voura. These were Diakopto and Stavria. Despite only providing two population counts, the 1879 census also showed that these settlements were themselves subdivided. Kirinitsa, Vrosthena, Kalyviti, Katholikon, and Pera Machalas were bracketed together in the census, together constituting the settlement of Diakopto. Each of these subdivisions were upland or mountainous, located between 477 MSL and 1,525 MSL. The second settlement listed in the 1879 Greek census, Stavria, was also an upland settlement, located at 512 MSL, but it was bracketed in the census with a coastal, lowland settlement named Tripiá. Ten years later, in the 1889 census, there is evidence that the process of lowland colonization had advanced. First, the five upland Diakopto settlements have divided into separate villages, each listed in the census with its own line and its own population count. Second, there were three new lowland settlements. Diakoptitika has emerged in the coastal plain, and it was labeled in the census as the “winter capital” of the deme; Kirinitsa was the “summer capital.” The fact that the census lists a “summer capital” and a “winter capital” supports Stamatoyannopoulou’s argument about seasonal migration during this period. Finally, in the 1896 census, we see that the lowland settlements grew, and a new one, Trapeza, also emerged. These examples from the Northern Peloponnese show the experience in the traditional currant growing core. Later in this chapter, a case study of Messenia in the Southwest Peloponnese shows the experience of a place where currant cultivation only began late in the nineteenth century. Tracking settlements in these municipalities, we see settlements concentrated in upland and mountain settings,25 liter pot then lowland settlements emerged as colonies for seasonal migration, and then they became permanent settlements. But was this because of the advance of currant cultivation?

While this is hard to prove definitively, there is good reason to believe it was. First, we know from production figures that currant output was growing in this part of Greece—it makes sense that this was accomplished through the search for more agricultural land. And second, population growth was greater in the currant-growing zone than in the other parts of the Peloponnese.From 1856 to 1889, the population grew by at least half in the currant-growing provinces of Korinthia, Achaia, Ilia, and Messenia . Population grew by a smaller percentage in the parts of the peninsula outside of the currant growing zone. It is also interesting to note that that population actually shrank in the eparchy of Kalavryta. This is compelling because Kalavryta is a mountainous region just adjacent to the currant-growing region in several places, as it abuts Korinthia, Aigialeia, Patras, and Ilia. This seems to indicate that people were moving from the mountains of Kalavryta to settle in the currant zone. In sum, in this part of Greece, there is evidence of demographic movement from uplands to lowlands, and population growth was greater in regions that were most suitable to currant viticulture. The narrative of lowland colonization in the Peloponnese due to the extension of currant vineyards needs to be qualified to avoid simplistic generalizations about upland and mountainous parts of the peninsula. It might be assumed that mountain villages in the Peloponnese and elsewhere in Greece became stagnant backwaters. If demographic growth was greater in the plains than in the mountains, does it necessarily follow that inland mountain communities disappeared or declined? It bears emphasizing that this was a regional phenomenon, mainly applicable to the northern and western coasts of the Peninsula. Different patterns were evident in other parts of the Peloponnese and elsewhere in Greece. This is not to suggest that, before this time, everyone in Greece lived in the mountains, then they all moved down. There was much more regional diversity than that, and upland villages remained populated and economically important. Doubtless, some inland mountain settlements did decline or disappear as their residents resettled in low-lying plains to grow currants. Nevertheless, Greek mountain villages on the whole did not become stagnant, “closed,” backwards, or isolated because of the demographic growth in the currant-growing zone of the coastal Peloponnese. On the contrary, mountains assumed important new roles in the changing economy. Some mountain villages became intensive agricultural producers in their own right, growing cash crops such as figs and olives, sometimes through the use of extensive terracing. Other mountain villages thrived because they provided useful resources to support the currant industry, such as timber. The currant industry required materials made from wood, such as wooden stakes used to support the vines and crates and barrels to transport currants.The expansion of the currant industry entailed a greater demand for these commodities as well, and they were likely made from locally-grown timber.

Steamdriven saw mills opened in that city in the second half of the nineteenth century to cut wood to be made into currant crates.In 1858, there were also 100 barrel factories in that city.The construction of railroads in Greece in the second half of the nineteenth century also created more demand for timber. Moreover, these railroads, as elsewhere in the Mediterranean, facilitated further timber extraction when they were completed. Mountain villages also served as important centers for industrial production. Mountains had long been useful in this role because of their water resources which were useful for activities such as tanning and textile production. Water flowing down sharp drops in elevation was used to power water wheels in mills. In the currant economy, mountain industry gained greater significance because of the timber extraction mentioned above. In addition to being sent to Patras to be processed at steam-powered saw mills, lumber was also locally processed at the place of extraction through the use of water-powered saw mills. These mills were established in forested mountain areas where there was access to moving water to power the saws. Logs were rolled down shoots to the mill, cut into planks, and carried by mules to be sold in cities.It is wrong to assume that all mountain villages generally declined during this period. Ulf Brunnbauer makes a useful distinction between “open” and “closed” mountain communities. If closed communities were isolated and economically backwards, open communities were integrated into larger social, cultural, and economic systems. They often specialized in crafts, relying on the surrounding plains for agricultural subsistence.Closed mountain communities may have declined during the golden age of currants, but open mountain communities remained viable. Like the plains, they were transformed in ways that supported commercial agriculture. Another form of land improvement that may have altered the landscape of the Peloponnese during this time was deforestation. Contemporary accounts by European travelers provide anecdotal evidence for deforestation in the Peloponnese. In 1855, Edmond About observed that Greece had such an abundance of trees that it “ought to export timber.” However, Greece imported timber instead. About blamed the lack of roads and the fact that peasants and shepherds burned down entire forests to clear land for grazing and for growing currants.The practice of “fire farming,” or burning forests to clear land for agriculture, was not unique to Greece, however—it was prevalent throughout Europe and the Mediterranean in the nineteenth century, as were state efforts to quash it.Occupational burning is also often necessary for shepherds, as it clears plants that animals cannot graze, and it promotes the growth of plants that they can. Moreover, Mediterranean vegetation is highly adapted to fire, and some Mediterranean plants require fire in order to germinate.In addition to clearing forests to make new land, it is also possible that deforestation was tied to the expansion of the currant economy in other ways.

As a result of harsher conditions in the lowlands and new crops from the Americas, from the middle of the sixteenth century to the middle of the nineteenth century, permanent settlement in the Mediterranean region became more concentrated in the hills and mountains. Populations that could not keep up with the drainage work in low-lying fields were forced to abandon settlements there and relocate to hillsides and mountains, which became more densely populated, and were transformed into the new epicenter of economic life. Without lowland stretches to plant grains, and with the removal of “oriental” crops from the Mediterranean , the region returned to its indigenous crops—olives and vines.The movement of cereals out of the Mediterranean meant that permanent settlement in the region’s low-lying plains was abandoned, and these plains were repurposed for seasonal migration and animal husbandry.Commercial agriculture left the shores of the Mediterranean from the middle of the sixteenth century to the middle of the nineteenth century. During this period, rural populations retreated from lowland settlements into the hills, and the agricultural landscape shifted from monocultural grain production in low-lying plains to polyculture,chicken fodder system primarily in the hills in mountains.

Around the middle of the nineteenth century, this upland movement was reversed. Two transformations caused a shift in land use and settlement patterns around the middle of the nineteenth century. First, as discussed above, the Little Ice Age came to an end around the middle of the nineteenth century. This made land reclamation in low-lying plains much easier.Second, market integration caused commercial agriculture to return to the shores of the Mediterranean. After 1750, there was a period of expansion of the world-economy. This was due in part to a demographic boom throughout Europe and the Mediterranean basin, which created increased demand for wheat and cotton. Higher demand for both of these crops made cultivation in the low-lying plains where these crops could be grown in large stretches a more attractive prospect. While the Little Ice Age climate was still in effect, lowland plains remained marshy, and lowland colonization was still more difficult and more deadly than it had been during the Medieval Warm Period. The demand for wheat and cotton, however, provided the incentive to overcome additional obstacles and undertake lowland colonization.

To reclaim wetlands under these conditions, it was often necessary to form large plantations worked by coerced labor. In the Ottoman realm, this took the form of çiftliks, which began to abound in lowland fields. Moreover, in the 1850s, quinine became more widely available in Mediterranean Europe, making malaria a less harmful disease.Colonization of low-lying plains continued to intensify throughout the nineteenth century, propelled by deeper market integration and greater global demand during the mid-Victorian boom and aided by the palliative effects of quinine. Nevertheless, most of the lowlands remained neglected through the middle of the nineteenth century.As a result of these two processes—market integration and the end of the Little Ice Age—by the middle of the nineteenth century, the low-lying plains of the Mediterranean were once again opened for settlement and tillage, beginning a process of downhill migration.As Tabak argues: “the relocation of oriental cash crops and commercial bread crops, the widening stretch of dispersal of manufacturing, and the growing weight of terrestrial trade led, in unison, to the long-term retreat of commercial agriculture in the region.”As a result of the disappearance of these major commercial crops, the Mediterranean basin became more self sufficient.From the eleventh century to the mid-sixteenth century, lowland plains had been claimed and tilled. Then, from the mid-sixteenth century to the mid-eighteenth century, the lowlands were abandoned.

In the mid-eighteenth century, the plains began to be settled again, with lowland reclamation picking up pace in the middle of the nineteenth century. Grains did not reappear in Mediterranean plains until the mid-eighteenth century and not in a considerable amount until the mid-nineteenth century.When cotton returned to the Mediterranean, it was not grown as a plantation crop, but as a niche crop—“another addition to the petty producers’ reserve, cultivated in smaller fields and mostly for local and regional markets.” In contrast, sugar disappeared completely from the Mediterranean, except for Egypt, where it continued to be grown but on a much smaller scale.In the period under review in this dissertation, the norm of risk-averse subsistence agriculture was challenged, and—in places, for a time—it was replaced by profit-driven capitalist agriculture. With the onset of the Little Ice Age and the relocation of plantation crops from the Mediterranean basin to the Americas, normative Mediterranean agricultural practice became like the “traditional” model described by the older historiographical tradition. In the second half of the nineteenth century, climate change, market integration, and technological innovations caused such changes in land use that this model began to break down. In the period under review in this dissertation, the so-called traditional model co-existed with and was being supplanted by a very different model of land use. In sum, the starting point of this dissertation envisions Greece at the beginning of the nineteenth century as an area composed of shifting, inter-dependent micro-ecologies in which populations strove to meet the needs of their own subsistence through diverse strategies in which exchange played a crucial role. This is the baseline which was altered in the late nineteenth century by the rise of specialized, intensive, commercial agriculture. As a result of growing foreign demand in the second half of the nineteenth century, Mediterranean agriculture became more specialized and more intensive.

The external forces acting on the ecological and agricultural systems of the Mediterranean began to change and, as a result, the character of agriculture in Greece and Mediterranean Europe began to change as well. There was a shift from the old Mediterranean norm of diversified subsistence agriculture, fragmented landscapes, and transhumant pastoralism to the new norm of commercial agriculture. This dissertation rests on the argument that, in the nineteenth century, the nature of Greek agriculture changed from a system oriented toward subsistence into a system oriented toward commerce. In the most basic sense, commercial agriculture was not new in Greece in the nineteenth century—far from it. The exchange of agricultural products existed as a feature of ancient and medieval Mediterranean economies, and, as mentioned above, exchange was built into the old agricultural system. The cultivation of cash crops intended for sale was just one among several strategies for meeting needs.Furthermore, beyond the cultivation of cash crops, any surplus not stored for later use could be sold or exchanged. Agricultural products had been exported from Greece and consumed abroad for centuries. One of the major forces that moved Greek agricultural production across long distances was a phenomenon known as tramping or cabotage, whereby small boats with small cargoes hugged the Mediterranean coastline, stopping in ports along the way to buy and sell. Through this process,fodder systems for cattle goods were relayed around the Mediterranean basin.The exchange of agricultural production in Greece has a very long history, as does the long-distance trade of Greek agricultural production. The term “commercial agriculture,” then, is not meant to refer to either of these phenomena, nor is the term meant to refer simply to the presence of specialized, intensive production of cash crops or other agricultural products for exchange or export. Large farms that specialized in the production of agricultural products to be sold or exchanged existed at least since the Ottoman period. The change that occurred in the second half of the nineteenth century was not, therefore, the appearance of a new phenomenon, but a dramatic growth in the scale of an existing phenomenon. From 1860 to 1893, Greek agriculture became more commercial, more specialized, and more intensive. First, agricultural practice in Greece became more commercial, meaning there was a greater participation in markets by agricultural producers. Small-scale producers became more involved in markets, and they moved from production for family subsistence to growing crops for exchange.

There was also a greater level of participation with markets that were farther away, particularly in Western Europe. Market integration with Western Europe was made possible by advances in transportation, particularly the invention of faster steam ships.Second, Greek agricultural production became more specialized, meaning there was an increasing move away from diversified agriculture and toward monoculture. At the small scale, cultivators moved away from diversification practices such as land fragmentation and poly cropping. Instead, to take advantage of economies of scale, certain elite cultivators consolidated large, contiguous land holdings growing the same crop. At the macro scale, different regions of Greece became associated with different monocultures. Finally, Greek agricultural production became more intensive, meaning that more land and labor were devoted to agricultural production. In sum, instead of diversification, there was a trend toward specialization and intensification; instead of family-level subsistence, there was commercialization. Landscapes became more homogenous and monocultural. There was also a trend away from transhumance toward settled agriculture. In the larger Greek world, several crops were important. Largely to satisfy foreign demand, different parts of Greece grew to specialize in the intensive production of different agricultural commodities including olives and olive oil, silk, and cotton. As a percentage of export revenue, currants were the most important crop in the Kingdom of Greece in the second half of the nineteenth century.As such, Greek historians have been interested in this period of currant monoculture, and there have been many studies of the currant question in the nineteenth century.In their studies on Patras, the “capital” of the currant trade in the nineteenth century, Bakounakis and Frangakis-Syrett have demonstrated that currants strengthened Greece’s trading connection to Western Europe and facilitated foreign access to Greek markets.From Pizanias, we get the history of the prices of currants—in Greece, France, and the UK—and a broader commercial history of the European demand for currants and its effect on Greek output. Petmezas writes about the role of currants and of agriculture in the larger Greek economy, and Nikos Bakounakis has studied the financial history of currant cultivation in Achaea.Other studies have addressed the effects of intensive currant production on peasant society and on land tenure practices. Franghiadis has shown how rural populations felt the pull of foreign demand for currants, and they undertook land improvement projects to extend currant cultivation. Bakounakis has elucidated how currant cultivators often went deeply into debt to finance the planting of their land with currant vineyards, borrowing from currant merchants at usurious rates.76In the nineteenth century, Europeans began changing their environments in more ambitious and more impactful ways than ever before, especially through the manipulation of water resources. Around the middle of the nineteenth century, Europeans began digging bigger canals and building bigger dams than ever before. They changed rivers, lakes, and wetlands, and they dredged navigation canals that connected seas and oceans—in short, they permanently changed the hydrosphere. During this time, a number of factors came together that led people to undertake these ambitious projects to “tame” the hydrosphere. First, there were new needs during this time that motivated these projects. Some of these new needs were the result of population growth—the population of Europe more than doubled over the course of the nineteenth century.This unprecedented demographic expansion created a need for more food and clean water than ever before, placing new demands on land all over the continent. New needs also sprung from economic growth. This created a need for faster and cheaper transportation—to sustain this economic growth, it became necessary to remove barriers to the movement of people and goods. Draining lakes and reclaiming wetlands provided new agricultural land, which was needed to feed a growing European population and to support growing agricultural economies. At the same time, rectifying inland rivers facilitated the movement of raw materials like coal and iron as well as finished products, supporting growing industrial economies. Taken together, these two process aided in connecting regions by increasing the speed and decreasing the cost of transportation. Efforts to tame the hydrosphere were not new, but in the second half of the nineteenth century, there was a sudden increase in the scale and the intensity of water management projects. Engineers in Europe and North America straightened rivers, dredged canals, drained wetlands, and constructed dams and reservoirs like never before. In addition to the new needs created by demographic and economic growth, three changes also made this change in scale possible. The first was new technology and new sources of energy.

Given this, financial institutions have come under governmental pressure to comply with banking regulations. In 2012 Chávez publically threatened banks in non-compliance with nationalization. In 2015, the Superintendent of theBanking Sector of Venezuela fined BancoCaribe bank 280 million bolívars for failing to fulfill agricultural lending requirements in parts of 2014 . The percentage of lending to the agriculture sector by private banks has risen since 2001 and has resulted in large increases in absolute amounts of credit delivered to the sector. Bank lending to agriculture had risen 114% from January 2014 to January 2015 . High annual inflation, however, greatly reduces the amount of real increase of credit levels and in some years eclipses it entirely. In 2014, agriculture financing increased 26% over 2013 funds but was essentially erased in real terms by a 53.4% inflation rate . Banks also must provide said loans to the sector at a preferential interest rate. As of July 2008 a government decree30 mandated that agriculture loans be lent out at a 13% interest rate. By way of comparison, bank loans to other sectors can carry an almost doubled interest rate of 24% . Although 13% is significantly higher than agriculture credits provided by some government institutions to small producers, where rates can be low as 3% and are often forgiven in case of non-repayment,dutch buckets low rates provide an important source of operating funds to commercial agriculture.

Lending to agriculture from commercial banks effectively functions as a subsidy to the operation of commercial agriculture ventures, which capture a majority of these loans as opposed to smaller, less credit-worthy producers who rely on the state for financing. Agrarian reform beneficiaries do not receive transferable title to land in order to avoid sales and reconcentration of land and therefore have no collateral to offer private sector banks. As this policy operates at the expense of commercial banks, it is unlikely that it would survive the passing of ruling control to an opposition government with a position of re-liberalizing segments of the economy. Policies that mandate private bank lending to agriculture create possibilities for high profits that are relatively unrelated to productive activities for well positioned growers, and incentivizes commercial farmers without actual need for credit to seek loans . While the stated goal of commercial bank lending requirements to agriculture is to stimulate production, loans often go largely into servicing old debt . High inflation effectively erases debt for producers allowing profit to be made by continuously taking out loans at each growing cycle. One commercial producer stated that by constantly taking out loans he made as much as a 10% profit from the funds as by the time repayment occurred the bolívar denominated debt has disappeared in real terms . Funds from loans can also be re-loaned out by recipients themselves into non-controlled channels where interest rates are higher. Thus, a cycle of taking private loans year to year—an activity unavailable to the peasant sector—maintains the commercial grower sector even within a context of low, controlled prices.

The Venezuelan government’s currency controls are also an avenue through which the commercial sector benefits from state policy. Venezuela has a three-tier exchange rate where dollars can only be purchased through the central bank for importation of goods and industrial inputs or for foreign travel. The cheapest rate for dollars, CONCOEX—6.3 BsF per dollar—is reserved for imports of food and medicine, underlining the importance for the government of securing food supplies.31 Access to official dollars essentially functions as a largely hidden subsidy to middle-class and other well-positioned actors in Venezuela with the wherewithal to travel abroad and own businesses requiring foreign goods and inputs. Foreign currency purchases at all official exchange rates are well below the black marketrate for dollars, which at writing was at 1,100 BsF per dollar. Dollars obtained through the central bank can be traded on the black market back into bolívars for many times their official value which can then be used for consumption or servicing debt. In one striking example, in 2013 international flights from Venezuela were booked months in advance yet were reported to be leaving half empty from the airport . Dollar advances obtained for travel combined with credit card scams where phantom purchases were placed cards with travel dollar allotments that were then paid out in cash, provided dollars that could be converted back into bolívars at black market rates. The gap in the official and black market rates meant that purchasing international plane tickets was in many cases a transaction made only to secure travel funds for black market exchange.

In off the record interviews, medium-sized importers of consumption goods admitted to me that both travel and phantom import orders had been used to access dollars. While the government has increased control over the exchange system to try to limit forms of currency arbitrage, and although growers interviewed were understandably reluctant to admit to engaging this illegal behavior, given the integration of grower associations and agroindustrial processors with access to food commodity imports, it is likely that many commercial farmers could avail themselves of parts of this system. Commercial agriculture also benefits from general agricultural subsidies for some agro-inputs and fuel that target producers at all levels of agriculture. Venezuela has a relatively well-developed national petrochemical industry that developed alongside its petroleum sector. Pequiven, the state petro-chemical company, manufactures urea and other fertilizers and supplies the national market with product below international prices for fertilizers. According to FEDEAGRO, Venezuelan urea is 5-6 times cheaper than foreign sources, in 2012 costing 19 BsF per 50 kilogram sack, versus 100 BsF price for non-subsidized urea . To bring more of the agro-chemical sector under state control the Venezuelan government nationalized of the largely Spanish-owned agro-chemical company Agroisleña in 2011. Agroisleña was transformed into AgroPatria, a stateowned enterprise that supplies pesticides and herbicides and other agrochemicals at below market prices to both commercial and peasant producers. Agroisleña controlled around 70% of agro-chemical and seed distribution in Venezuela and its nationalization was oriented towards ensuring a low-cost supply of inputs to the agriculture sector in order to boost production . There were also a number of other state-owned AgroTiendas that sold inputs at subsidized prices. Producers registering with AgroVenezuela were to receive streamlined access to state-managed agro-inputs at ‘just’ prices. Ostensibly, this lowered production costs for commercial producers whose industrial production systems were heavily reliant on large quantities of chemical inputs. However, producer associations asserted that supply and quality problems of AgroPatria complicated crop production. Growers reported that followed nationalization inputs were often unavailable at the needed time in the growing cycle, or that there wasn’t sufficient quantity of available inputs from AgroPatria ,grow bucket incidentally a claim repeated in interviews by peasant producers as well. In 2015 FEDEAGRO reported that AgroPatria had only supplied 50% of white maize seeds, 22% of yellow maize seeds and only 18% of agro-chemicals requested by producers for the season . Critics cited reduced production after Agroisleña’s nationalization and increased diversion of inputs from AgroPatria to the black market where inputs commanded higher prices, often three to four times above the market price . This contributed to lack of sufficient input availability in AgroPatria for both commercial growers and smallholders. FEDEAGRO complained that the MPPAT’s policy was to allot equal proportions of state-controlled inputs to the commercial and state sectors, even though FEDEAGRO claimed that the private sector was responsible for 85% of national agriculture production and, thus, required more inputs .

FEDEAGRO argued that over-allotment to the state sector of inputs fed diversion into the black market and increased scarcity at subsidized prices . Although agricultural inputs were reportedly not reliably available in new, state stores, they could often be found from private distributors or on the black market. Yet the high prices for inputs charged at these outlets largely defeated the stated purpose of AgroPatria of low-price input distribution. Commercial growers could more easily utilize private agro-chemical distributors than smallholders due to greater capitalization and access to private credit. This allowed commercial growers to both benefit from lower input prices at state AgroTiendas for a portion of input costs, and maintain flexibility in face of disruptions to state-managed distribution chains. However, private input providers couldn’t compete with AgroPatria’s below market prices, and were, thus, often ill-positioned to fill shortfalls when they emerged. In addition, growers claimed that some agrochemicals were of inferior quality post-nationalization . Agroisleña had bought active chemical ingredients of inputs and mixed them in-country, while due to production difficulties, AgroPatria often imported some pre-mixed, and lower quality, chemicals . After nationalization, commercial growers had to pay upfront for input orders by making cash deposits with AgroPatria, while with Agroisleña grower associations would purchase on credit and service their debt after selling crops, reducing the amount of pre-harvest capital needed at the beginning of crop cycles. Grower associations were also able to leverage bulk input purchases for its members to access discounted rates on inputs bought from AgroIsleña, which they could warehouse and distribute to members as needed. The need to go to AgroPatria, cash in hand, combined with the difficulty of obtaining sufficient inputs of sufficient quality in the correct time frame, disrupted commercial accumulation processes even as some degree of cheaper inputs helped to reduce production costs. The chief complaint of commercial growers in regards to state agricultural policy was the regime of price controls on many agricultural and food products. With the rise of oil prices and increased rent circulation in Venezuela, persistent high inflation pushed prices of consumer goods higher. To combat high inflation of food prices and perceived ‘unjust’ prices offered by merchants the Venezuelan government began to set maximum prices in 2004 on a number of basic food items that made up the ‘food basket’ of the Venezuelan public. This included sugar, rice, grains, corn flour, chicken, sardines, pork, steak, cooking oils, milk and others . Prices are regulated by the National Superintendent for the Defense of Social Economic Rights which sets maximum prices for producers, wholesalers and consumers, effectively regulating the farmgate and market price. Low controlled prices are a common complaint among both commercial and some peasant growers, especially in the coffee sector where there are many small producers. Growers contend that prices are often below production prices, which is exacerbated by input and labor costs rising faster than adjustments to crop prices. Coffee producers claimed that production costs in 2014 for a quintal of coffee was between 5,400 and 6,500 BsF in Portuguesa, over double the controlled price at the time of 2.657 BsF . Coffee prices were raised in September 2014 to 4,500 BsF to close the gap yet remained below the stated production prices. 32 The price of rice was last raised in October 2014 from 8.6 to 23.6 BsF per kilo , a figure significantly lower than the 38.74 BsF per kilo requested by the Venezuelan Association of Rice Processers . Growers also contend that SUNDDE’s price adjustments are often irregular in timing. Price uncertainty causes many headaches for growers who argue that not only are prices too low for many crops, delays in price adjustment, especially in the face of inflation, mean that farmers may have to plant crops without knowing what the controlled price will be at harvest time. While price uncertainty is, of course, present in open markets and dealt with in part through contracts and hedging, controlled prices could be theoretically set before plantings by the government. Regulated prices contribute to the diversion of food from controlled into informal markets where they command higher prices. According to rice processors and producers only 30% of rice consumed in country is sold at the regulated price while the rest is sold on the black market. Food manufacturers also avoid price controls by processing controlled crops into other, non-controlled forms, such as processing rice or milk into flavored rice or cheese . As a partial response to this strategy of price evasion through processing, SUNDDE set a policy that flavored rice could only be sold at 25% above the controlled price for rice , limiting manufacturers’ ability to avoid price controls. Export restrictions mean that growers cannot easily move crops into export commodity chains in search of higher prices, which, as was the policy’s intention, keeps production in country.

Anything we can find out now can be used by regulators to make more informed decisions.” Letourneau takes nothing for granted as the research gets under way. The project will use a large number of sample plants on varied research sites, and the experiments will be replicated over three years. Hazards of GM corn, including allergenicity and contamination of adjacent fields, were identified during extensive testing that was required because it is a food. Because similar tests are not required on nonfood plants, it’s harder to know what the hazards might be, and what the probability is that they’ll occur, said Letourneau. “It might be that transgene movement to wild relatives would be no problem at all,” she said. “If we don’t detect any problems or hazards, we’ll feel we’ve tried to provide the data needed for risk assessment.” The three-year project is funded by a $335,000 grant from the U.S. Department of Agriculture.Some cover crops can both benefit your crop rotation or winter fallow and help limit gopher populations. Research has shown that gophers much prefer clover cover crops over small grains such as barley,hydroponic nft channel oats and Sudan grass. And although most clovers attract gophers there is a sour clover that appears to discourage them.

This can be used as a winter cover combined with a small grain to move populations out of the fields to areas where they can be trapped. I’ve also observed that gopher populations move to farm road edges and other border areas when a winter cover crop of bell beans or fava beans are planted. Be aware, though, that many studies have shown gophers to be extremely adaptable in their feeding habits, so no cover crop will guarantee a gopher-free field. When considering rotations on diverse farms, include gophers in the equation. If you follow a crop that attracts gophers, such as potatoes, with another that they feed on, like onions, you will exacerbate gopher problems by providing a continual food source. However, if you follow potatoes with a sour clover or small grain, populations are less likely to rise. Farmers and gardeners have tried all manner of barriers to discourage gophers. These include wire mesh, gravel, trenches filled with glass and rocks, corrugated roofing, even trenches with buried buckets that act as pitfall traps—anything that presents an obstacle for persistent gophers. These all have some effect on slowing invasions. The most promising approaches are those that create both an above- and below-ground barrier.

One of the most successful is fencing made of steel corrugated roofing. Not only is it impenetrable, but gophers cannot climb the exposed portion. Because gophers can scale a welded wire fence, above-ground wire barriers must have the wire bent outward at the top or a wooden or metal rim installed. I’m currently experimenting with a material called “Root Guard,” a thirty-six inch wide plastic sheeting seventy mils thick used by landscapers to keep bamboo roots from spreading. At $3–$4/foot, Root Guard is too expensive to use in large-scale operations, but may be cost effective for areas of an acre or less. Large farms may benefit by blocking major gopher access routes with any available solid material, but I don’t believe there is a viable material that will completely head off an infestation.Although not appropriate for all operations, flood irrigation can be extremely effective not only at killing gophers under the water but also at driving the survivors to field edges where they can be trapped. Flooding burrows with a hose can sometimes be effective in a small operation, providing that it is done at a fresh burrow. Gas cartridges with sulfur and sodium nitrate as active ingredients are still allowed by organic certifiers and can be effective if used on new burrows . They cost $1–$2 per cartridge and have an approximately fifty percent success rate. After inserting a gas cartridge in a burrow, be sure to cover the opening to prevent the gas from escaping.

One company sells a blower that is supposed to move the gas beyond blocks in the tunnel system. I feel this may dilute the strength of the gas, although no scientific evidence yet exists to validate this idea. The “Rodenator Pro” is a device that injects a mixture of propane gas and oxygen into a gopher burrow and then ignites it with a spark, destroying the tunnel system. I recommend occasional use of the Rodenator in vineyards and orchards to remove permanent tunnels that run along perennial crop rows. It’s not appropriate for annual vegetable operations as it can damage crops and is unwieldy in row crop settings. Some growers use trapping as a main strategy and the Rodenator for areas where gophers and ground squirrels have settled. A truck or tractor is needed to move the propane and oxygen tanks around the site to be treated. Barn owls are the most effective gopher predators—their diets can consist of up to ninety percent gophers, and a barn owl family attracted by a nest box can eat up to a thousand gophers per year. There are many designs for barn owl nest boxes . The main criteria is that the box’s opening be approximately five inches in diameter; any larger and the barn owl’s main predator, the great horned owl, can get at the young birds Gopher snakes do in fact eat gophers, but only one every six weeks to two months. Bobcats and coyotes also eat gophers, although I’ve found that coyotes prefer gophers caught in traps, which often disappear after they dine. Domestic cats can be a significant help in controlling gophers. Cats hunt more when well fed and cared for, as the sporting aspect seems to be the attraction. After poison baits, which are no longer allowed under organic certification rules, trapping is the most effective way to control gophers.

The best sites for setting traps are where there has been recent activity, marked by fresh mounds of moist, dark soil in the morning or by holes that have been recently plugged. Three trap designs currently dominate the market. The most common in California is the Macabee trap, invented by Zephyr Macabee in 1900 to protect his Santa Clara Valley almond orchards. The Macabee is a “pincher” type trap that impales two wires in the body of the gopher when it bumps into a trigger. The usual set for these traps is to locate and dig down to the main, larger burrow and insert two traps facing away from each other, connected by a wire. After the set is completely buried the wire is left on the surface and flagged to help find the traps. There are different opinions about letting light and air into the tunnel where the trap is located. Some say light and air will encourage the gopher to pack the trap area with soil and not set the trap off,nft growing system and some say it is the light that draws the gopher to the trap. I’ve found that both methods work and that adding some vegetative bait helps as well. I’ve seen some modifications where the Macabee trap is inserted into a section of two-inch ABS drain pipe about eight inches long, either left open or closed at one end . This addition seems to help catch the gopher even if it is pushing soil ahead of it. Another older, standard trap design that is still popular is the box trap. This small wooden box is open on the bottom and at one end, and houses a trigger and metal “choker” loop or cable that grabs the gopher as it enters. A more modern version called the “Black Hole” is made of plastic tubing and a cable choker. These traps work by fooling the gopher into thinking it is still in the tunnel. The gopher is lured to the end of the trap where a small opening allows light and air in and the gopher gets caught trying to close the opening. Box traps are also placed in the main tunnel in pairs, although I’ve seen a single trap work when placed in the mound’s entrance tunnel. Although both Macabee and box-type traps are effective, I’ve had the most success using the Cinch trap from Oregon. This is also an older trap that for many years was used only by professionals and can be slightly hazardous and difficult to set due to its double trigger and strong spring. It was originally designed for moles but is extremely effective on gophers. Like the box or Macabee traps, Cinch traps can be used in pairs, but can be set more quickly and can be even more effective than the other trap types when placed singly in the burrow entrance. The method I use is to open the burrow at the freshest mound and insert the round, extended jaws of the trap into the burrow entrance. I use a stake that is sized to open the burrow as wide as the trap’s jaws and then use the same stake to mark the trapping site.

The gopher is caught when it comes to the surface to close the opening in the mound. Interestingly, the unvacuumed trap crop treatment did not show a significant difference in damage when compared to the vacuumed trap crop in June, even though it accumulated more WTPB in rows 1–8. Also interesting is the fact that the highest damage was seen in the untreated control, which did not accumulate high numbers of WTPB. This could indicate that WTPB not associated with or feeding on nearby trap crops do more per capita damage to strawberries. “It’s possible that trap crops may partially satiate WTPB and thus minimize the amount they feed on developing berries, so that WTPB abundance alone does not correspond well with strawberry damage estimates,” says Swezey. “This is a hypothesis we plan to pursue in future research.” In July, vacuuming the alfalfa trap crop reduced WTPB numbers by 79% compared to the unvacuumed trap crop . Except in row 1, the vacuumed trap crop treatment also had the same accumulated number of WTPB as either the whole-field vacuuming treatment or the untreated control. Vacuuming the trap crop reduced total damage to the strawberries in July by 49% when compared to the unvacuumed trap crop , although no significant differences could be detected between the vacuumed trap crop and either the whole field vacuuming or untreated control treatments. These results show that in July, WTPB in an unvacuumed trap crop will generate significantly higher damage to adjacent strawberry crops than other treatments. “We do not want the trap crop to become a source of pests,” says Swezey. “That’s why it’s critical to manage it throughout the growing season.” The research team is still evaluating data collected in August 2003 to see whether the differences in treatment continued through the late season. The big-eyed bug , Geocoris spp., was the most abundant beneficial insect collected from the trap crop and strawberry fields. This native insect feeds on WTPB eggs and nymphs. Results from the 2002 study show that in June, the vacuumed trap crop treatment had significantly more BEB in the trap crop and all strawberry rows than did the other three treatments. This result indicates that the trap crop vegetation increased the numbers of the most abundant generalist WTPB predator in the strawberry rows at the farthest distance sampled. This effect was somewhat less prevalent in July, and by August BEB populations had declined in all the treatments, possibly as a result of the BEB entering diapause.Results from 2003 are still being analyzed.Results from this study show that a field edge alfalfa trap crop can successfully attract and concentrate WTPB numbers, and that tractor-mounted vacuum devices can remove significant numbers of WTPB from the trap crop. The trap crop vacuuming treatment offers the same or reduced WTPB damage to fruit in adjacent strawberry rows when compared with the grower’s whole field vacuuming program. “The study also showed us that, at least for WTPB, alfalfa is a terrific trap crop,” says Swezey. “We wanted to develop a type of vegetation management system specific to this pest, and I think we’ve shown that alfalfa is effective.” Swezey also cautions that trap crops must be used carefully. “It’s one of those ‘Don’t try this at home’ situations,” he says. “If you’re going to use trap crops, you have to be ready to manage them as diligently as the crop itself—that includes irrigation, fertilizer, and weeding—and then you have to manage the pest once it’s in the trap crop.” Perhaps the most important result for the Pacific Gold growers was that vacuuming the field-edge trap crop reduced the operation time of their tractor-mounted vacuum by 75% as compared to vacuuming the entire strawberry field, while giving the same or better level of WTPB control. This approach to limiting WTPB damage translates to savings in operator time, tractor wear, and fuel costs.

If our use of natural resources precludes future generations from using these resources, then it may not be a just policy when viewed from the eyes of future generations. In particular, using Rawlsian notion of justice, when generations make decision using veil of ignorance about which generation they belong to, if they are unlikely to decide to make reservoirs, then such reservoirs are made unjustly. Sidgwick put this statement differently by demanding anonymity in such utility ranking:i.e. the outcome of a preference ordering among different welfare paths between generations shouldn’t differ based on which generation is making the decision . Unfortunately, the concept of intergenerational equity has yet to be incorporated satisfactorily in economics: the major instrument in NPV calculation is a positive discount rate that leads to the finite NPV of infinite stream of incomes. Some sort of contradictions plague almost all proposed models such as paternalistic consumption models, paternalistic utility model, Chichilinsky’s model and Alvarez-cuadrado et al is model that improves on Chichilinsky’s model by guaranteeing optimal path of renewable resource extraction.

The major problem lies in the inability of comparing these utility streams: undiscounted utility often has NPV equal to infinity and one can’t Pareto rank them , Svensson. Discounting on the other hand has always been very controversial,blueberry grow pot in particular in environmentally sensitive projects. Our model uses discounting as a tool not only to ensure the finiteness of present value of the dam, but also in incorporating the stochasticity of future developments. Other studies of reservoirs have skipped the discussion of discounting altogether. Often,sustainability frontier of a dam is defined in terms of two ratios: Kw and Kt ; where Kw is defined as above and Kt is the ratio of storage to annual sediment arrival. Basson and Palmieri et al both provide a lengthy discussion on sustainability frontier in terms of Kw; and Kt : If a non-sustainable outcome is economically desirable to a sustainable outcome, then the reservoir can’t be sustained. Such economic desirability is expressed in terms of net present value of the reservoir under the two conditions. If NPV of the reservoir under sustainable outcome is higher than the NPV under unsustainable outcome, then the reservoir is sustainable. Often, higher Kt is more likely to yield sustainable outcome than lower Kt for a given Kw:We provide a new approach to model sedimentation management problem in large reservoir. This paper contributes to existing scant literature in what is being realized as an important topic in natural resources economics. Our model allows uncertainty in sedimentation accumulation, which is useful in understanding the impact of global warming or fluctuating weather if they contribute to the change in variance of sediment arrival rate in the reservoir.

This paper also contributes by providing a new algorithm to solve a particular type of boundary value problem arising due to the quadratic nature of the cost function. Quadratic cost function leads to nonlinear second order value function. Though there are several existing algorithms to tentatively solve these equations, all of them have some deficiencies. Some , such as nonlinear shooting methods, could be very slow, while others such as finite difference method are computationally cumbersome. We provide a new nested method that is a slight modification of the projection method provided by Judd. We calibrate our model by using the data from Tarbela dam in Pakistan. Tarbela is one of the most vulnerable dams in the world right now, because of its apparently high rate of erosion. We find that the dam could be sustainably operated for a particular linear cost function, and also for the quadratic cost function. However, we note that there are other issues that could make these assertions weaker. Removing sediments, for example, would also require finding a proper place to dump those sediments. Our model is simple and yet useful in understanding the issues surrounding the reservoir management. We provided many comparative statics results such as impact of increased sediments, impact of change in discount rate and impact of increased uncertainties on both value function and control functions. In both our basic model and our definition of sustainability, we focus on the major role played by water storage level on the value of the reservoir or on the sustainability criterion. Getting useful data on large dams is still very difficult.

Dams also differ by their location, their political significance and their strategic and even psychological meaning in the host country. Each dam is also likely to have its own specific cost function of removing sediments from the reservoirs. Reservoir operators are just recently beginning to think about sustainability of the reservoirs. Tarbela’s planners had originally planned the dam to operate for fifty years, a target they don’t like to stick to anymore. While the planners are now beginning to weigh different options for sediment removal, our results show that they are not too late in implementing those strategies. Future research in sediment management should look at the risk averseness of the planner. We use a risk neutral planner in our paper. Furthermore, since privately operated reservoirs are often licensed to run for a limited period , one would want to introduce a time dependent model to study the situation of private ownership. In this situation, optimization decision will yield a partial differential equation with time as one of the arguments. The welfare impact of allowing privately held reservoirs is also important next step in this field. However, the most important of all is better understanding of cost function. Right now, the understanding of cost function in sediment removal problems is very limited and it hinders effective management of reservoirs. Also, a major weakness of the model is its assumption that V0 and VK are known. The calibration assumes that VK is the cost of construction. It is an ad hoc assumption and probably is an underestimation of the value. A better understanding of such values could be derived only by, or at least in conjuction with, other economic techniques such as non-market valuation methods. Finally, in a lot of cases, a mixed model, in which different sedimentation strategies are used together are used. Modeling such a situation is more complex,hydroponic bucket but could be one of the topics of future research.Following the concept used by Kuznet to describe income-inequality relationship , an Environmental Kuznet Curve was developed to describe relation between environmental quality and income. Generally speaking, this relationship is considered to be of a quadratic shape. This means pollution goes up to a certain point as income increases, eventually declining above a certain level of income commonly known as a turning point. This type of relationship exists because countries generally pass through an agricultural phase into an industrial phase and then finally specialize in the service sector. In the agricultural phase, countries have little pollution.

As a country transforms to an industrial phase, pollution increases-originating from both point and non-point sources. Agricultural production becomes more intensive as little emphasis is placed on improving environmental practices and more emphasis is placed on the amount of food produced. Therefore, pollution continually increases.As the country transforms its economy to the service sector, pollution declines because the country imports pollution-intensive products from abroad. Therefore, one would observe a downward trend in total pollution. Income also increases in this phase of growth. Another reason why one would observe this EKC type of behavior is due to people’s preferences. It is generally thought that environmental quality is a luxury good; therefore, as per capita income rises, emphasis is placed on increasing environmental quality. This traditional inverted U-shape of the EKC has been challenged because many researchers claim that the relationship may not be depicted in a quadratic framework. For some pollutants, one would observe a cubic pattern whereas for other pollutants for which assimilation rates are low, the pattern may be monotonically increasing. Pearson as well as Cole, Ryaner, and Bates are dissatisfied with the econometric progress on functional form specifications in the studies of the EKC. To address these concerns about the shape and econometric estimation of the income- environmental quality relationship, other functional forms of income have been proposed and the relationship between income and pollution has been modeled in a non-parametric form. Semiparametric methods have also been used; where in addition to income and its different functional forms, additional variables have been also added to the regression model . A few authors have even considered adding variables such as governance in EKC models . Yet other rauthors have been frustrated with the sensitivity of the results to the slight changes in the data used . Therefore, the EKC concepts introduced by Grossman and Krueger and popularized by the World Bank have been getting increased attention. The objective of this paper is to look at how CO2, a stock pollutant, can be related to per capita income in Latin American countries. This study explores this relationship using both parametric and semiparametric panel data models. This study also shows that a parametric quadratic relationship is rejected in favor of a semiparametric estimate. Furthermore, we used hitherto unused data on forestry acreage in our study. We reviewed literature that examines the relationship between CO2 and per capita income discussing the results found within the literature pertaining to CO2 in terms of the model used and turning points. Several papers have revealed an inverted U-Shaped EKC relationship between CO2 and income using data from various countries utilizing various econometric methods.For example, Schmalensee, Stoker and Judson studied CO2 emissions data from 141 countries for the period 1950-1991, and use a spline functional form in a two-way fixed effects model. Sengupta used a fixed effects quadratic model in addition to data from 16 developed and developing countries. Carson , Jeon, and McCubbin utilized data from U.S. states.All three of these papers found an inverted relationship between CO2 and income. Bengochea-Morancho, Higon-Tamarit and Martinez-zarzoso analyzed 16 years of data from the European Union using a polynomial quadratic along with cubic specification in parametric fixed and random effects panel models; their study discovered an inverted, Ushaped EKC when examining a selected subset of countries.Panayotou, Peterson and Sachs used feasible generalized square method to establish the presence of an inverted U-shaped EKC in a subset of the 17 developed countries in their study. Other studies supporting an inverted U-shaped EKC are Moomaw and Unruh, Friedl and Getzner , and Millimet, List and Stengos. Contrarily, there are other papers that reject the inverted, U-shaped relationship between existing between CO2 and income. For example, Shafik and Bandopadhyay claimed that one might see a monotonously-increasing relationship between CO2 and income. To reach this conclusion, their study utilized 26 years of CO2 data from 118 to153 countries as well as polynomial specification in both fixed and random effects models. Holtz-Eakin and Seden used a two way fixed effects model with a quadratic functional form to analyze data from 108 countries, and unveiled that the turning point could be as high as $8 million dollar per capita. Agras and Chapman indicated that there may not be any turning point for CO2 based on their study of 34 countries using a fixed effects autoregressive distributed lag model. Moomaw and Unruh and Dijkgraff and Vollebergh used data from OECD countries from 1950-1992 and from 1960-1997, respectively; both rejecting the presence of a quadratic relationship between CO2 and income. Nguyen, in a study using a non-parametric method, indicates that there is a convergence in CO2 release among OECD countries. This view is also supported by Strazicich and List in their analysis of 21 industrial countries for the period ranging from 1960 to 1997. Other studies have also rejected an inverted U-shaped EKC .We have observed that different authors have used CO2 data from various sources to study the EKC relationship-with data originating from the World Bank, Oak Ridge National Laboratory, World Development Indicators, World Bank, OECD environmental data sources and the International Energy Agency. The postulating of the functional form was done utilizing linear, quadratic, cubic and spline functional forms. Estimation techniques used include parametric panels, fixed and random effects models, time series method, non-parametric methods, semiparametric methods, and pooled mean group estimations.

A defined urban boundary that reduces the area of interaction between urban and agricultural landscapes, however, could reduce any potential heat island and runoff effects on agriculture. By leaving larger tracts of agricultural landscapes intact, the interface problems are, to a degree, mitigated.Population expansion in Yolo County, the Sacramento Region, and northern California in general can be expected to expand customer base for agriculture . These potential increases are quite significant, on the order of two million additional residents in the Sacramento region and many more in northern California, and so might lead to expanded opportunities for locally‐ or regionally‐oriented agriculture. Expanded urban populations might also provide a financial base with which to pay rural communities for ecosystem services , and a prime market for ecotourism within agricultural areas.Strengthening the urban community’s interest and support of farmland preservation is a key challenge for mitigation of GHG emissions, and the long‐term viability of agriculture in Yolo County. During the past several decades California communities have come to accept increasingly higher densities within their borders,nft hydroponic system and there is no reason not to expect this trend to continue in the future.

Awareness of the value of local food production and other associated ecosystem services of sustainable agriculture is one of the motivations that will likely move people’s attitudes toward support of land use policies for infill and compact growth in the B1 and AB32+ scenarios. One basic assumption of time series analysis is that of stationarity. That is, the mean and variance of a time series are constant over time. When they are constant over time, the series is stationary, and when they change over time, the series is non-stationary. In most time series data and models, this stationary assumption is unlikely met, and violation of this assumption complicates statistical analysis of time series. The major consequence of non-stationarity for regression analysis is spurious correlation that leads to incorrect model specification. To avoid spurious regressions, it is important to test for non-stationarity of the time series. A quick glance at the data indicates that the key variables in our analysis are not stationary . The first step is to conduct a formal test whether the data are “trend stationary” or not. In particular we test if the series have a unit root . If a unit root is found, the data are nonstationary. However, if the data are trend stationary, then analysis can proceed by regressing levels on levels with some function of a trend included in the regression to detrend the data.

The presence of a unit root is often tested using the augmented Dickey‐Fuller method. The test is carried out for each variable by regressing the first‐difference on a constant, a time trend, once‐lagged level , and p lagged differences, where p is chosen by the analyst . For the unit root test, the t‐statistic on the lagged level is the relevant test statistic. The usual t critical values, however, are not applicable. Appropriate critical values are given in Enders . Results from the augmented Dickey‐Fuller tests are reported in Table 4.1. Among the climate related variables, the presence of a unit root can only be rejected for the precipitation variable, meaning that all climate variables but the precipitation variable are non-stationary. For acreage variables, none rejected the presence of a unit root, indicating all acreage variables are non-stationary. Test on most price variables cannot reject the presence of a unit root. A few price variables, mostly the prices of orchard crops, narrowly reject a unit root. But, overall, most price variables are non-stationary. Given the failure to reject unit roots by most variables, the next step is to test for cointegration.If the left‐hand side and right‐hand side variables are cointegrated, then analysis can proceed with an error correction model even though data are non-stationary. However, if there is not strong evidence of cointegration then regressing levels on levels will lead to spurious regression results and reliable estimates are only obtained by regressing first‐differences on first‐ differences. The variables are tested for cointegration by two separate methods.

The Engle and Granger method regresses levels on levels and tests the residuals for a unit root. If the residuals do not have a unit root, then they are cointegrated. Thus, the null hypothesis of the test is that the variables are not cointegrated. The Dickey‐Fuller critical values are not applicable in this case, but appropriate critical values are found in Enders . As a robustness check, cointegration is also tested using the Johansen test with critical values found in Enders . Engle‐Granger cointegration test results are given in Table 4.2. There was very little sensitivity of the results to the method used, so the Johansen test results are not reported. For each crop, the cointegration test was performed by regressing acres on its own lagged price and the relevant climate variable for that crop, and then testing the residual for a unit root with the augmented Dickey‐Fuller test. Precipitation was not included in the regression, since a unit root is rejected for precipitation. The relevant climate variable for all field and vegetable crops, except wheat, is summer growing degree days; wheat acres were regressed on winter growing degree days instead. The relevant variable for tree crops is chill hours. There is only evidence of cointegration for 4 out of the 13, and for 2 of these crops the null hypothesis is very narrowly rejected. Given the results from the unit root and cointegration tests, estimates from regressing levels on levels could simply be spurious correlations. While it may be acceptable to specify an error correction model for a few crops , we prefer that all acreage equations be estimated with the same methodology. Given the strong evidence in the data of unit roots with no cointegration between the variables, we regress differences on differences for every crop equation. Current agricultural practices rely on relatively large inputs of nitrogen to support crop growth. The majority of N in California is applied in the form of synthetic fertilizers. Organic sources of N from crop residues, animal urine, and animal manure also contribute a significant amount of N to agricultural soils. Emissions of N2O are a natural by‐product of the nitrification and denitrification processes carried out by soil microbes. Nitrous oxide emissions are only a small fraction of the total N applied and essentially represent inefficiencies in the microbial nitrification and denitrification processes. Direct N2O emissions are defined as those arising directly from farm fields following N application,hydroponic nft system while indirect emissions are the result of volatilization, leaching, and runoff which carry N off the farm and into the surrounding environment. The equations used to calculate direct N2O emissions from synthetic N fertilizers, crop residues, urine deposited in pasture, and animal manure are listed below. Indirect N2O emissions arise from applied N that is lost from farm fields either as gaseous ammonia and aqueous nitrate in runoff or leachate. The first pathway is due to the volatilization of NH3 from synthetic N fertilizers, urine deposited in pasture, and manure. Volatilized N is returned to the soil through atmospheric deposition, where it is subject to loss as N2O during nitrification and denitrification. Nitrate in runoff and leachate collects in streams and water bodies where it is undergoes denitrification. Indirect emissions are estimated based on the amount of N added as synthetic N fertilizer, urine and manure, default values for the volatilization and leaching, and emission factors established by the IPCC .

The combustion of fossil fuels to run agricultural machinery produces CO2 and smaller amounts of nitrous oxide and methane . To calculate emissions from mobile farm equipment for a given crop, data on diesel fuel use per unit area was obtained from the University of California Cooperative Extension’s cost and return studies . The fuel use data was then multiplied by each crop’s annual cultivated acreage and then summed across all crops to estimate Yolo County’s aggregate fuel consumption. The amount of CO2, N2O, and CH4 produced from the combustion of diesel fuel was determined using emission factors for each gas published by the U.S. EPA and EIA . The advantage of this method is that it captures changes in fuel consumption related to annual trends in acreagenfor specific crops. However, since the approach assumes a fixed set of management practices for a given crop it, will not reflect the adoption of alternative practices such as reduced tillage or the use of alternative fuel sources . Irrigation pump engines can run on diesel, natural gas, liquefied petroleum gas, butane, gasoline, or electricity from the grid or solar PV. Diesel‐fueled irrigation pumps are known to be a significant source of both gaseous emissions and particulate matter, thus they are monitored periodically by the California Air Resources Board. Since detailed data at the county/air district level are available only on diesel pumps, we have only included this pump type in our inventory. Emissions from other fossil fuel‐powered pumps are not included because adequate local data were not available. As of 2003, an estimated 643 diesel‐powered irrigation pumps were operated in Yolo County . Statewide, the number of diesel irrigation pumps was projected to increase by 3.5 percent between 1990 and 2010 . We estimated the 1990 and 2008 pump populations based on an assumption that the statewide trend was proportional to the increase in the number of pumps in the county. Input values for engine activity and average engine horsepower were taken from statewide survey data . Diesel fuel emission factors for CO2, N2O, and CH4 were taken from the U.S. EPA and the EIA .The main mechanism of CH4 production is enteric fermentation, which involves microbial breakdown of carbohydrates in the digestive system of ruminant livestock . Several non‐ruminant livestock also depend on enteric fermentation to help break down poor quality plant material in their caecum and large intestine, but produce less methane than ruminants. A secondary source of CH4 from livestock is the manure they produce, and more important, how it is stored. Manure deposited in the field orpaddock decomposes under aerobic conditions and thus produces little or no CH4. However, when manure is stored in lagoons, as is common in dairy and swine operations, large amounts of CH4 can be produced via anaerobic decomposition. Nitrogen in livestock urine and manure is also subject to loss as N2O during nitrification and denitrification. In this inventory, we assume that all N excreted by livestock is applied to soils either as urine or manure, and thus the emissions are included in the direct and indirect N2O emissions categories. This approach is justified given that the vast majority of livestock in Yolo County are grazed on pasture or rangelands and the manure management methods used by the small number of local dairy and swine operations are well‐known. Methane emissions from enteric fermentation and manure management were calculated for each livestock category using a Tier 1 approach and records of livestock numbers reported by the National Agricultural Statistics Service database or the Yolo County Agricultural Commissioner’s reports . The equations and tables below summarize the method used to estimate CH4 emissions from livestock.The major pathway by which climate change will affect the California economy is through its impact on the California water system. Therefore, a major component of the climate change research being conducted at the University of California, Berkeley, is an economic analysis of the California water system to assess the economic costs associated with changes in the reliability of supply for water users in various parts of the state. Compared to previous research, the approach that the research team has adopted for measuring the economic impacts of climate change has two distinctive features. First, the primary spatial unit of analysis is the service areas of individual retail water supply agencies—irrigation districts and urban water agencies—as opposed to broader geographic aggregates of districts such as depletion analysis areas. To the maximum extent possible, this analysis will be disaggregated to the level of the individual water district. It is important to avoid any further aggregation, because there is tremendous heterogeneity among different water districts even within the same county in California with respect to their water source, the nature and age of their water rights, their operational costs, their finances, the price they charge their retail customers, and other aspects of their terms of service.

Fuel use for irrigation pumping was calculated as the product of the number of diesel‐ powered irrigation pumps in the county, the estimated annual activity of each pump , the average brake horsepower of pump engines in the Yolo/Solano Air Quality Management District, and the brake specific fuel consumption per hour . As of 2003, an estimated 643 diesel‐powered irrigation pumps were operated in Yolo County . Statewide, the number of diesel irrigation pumps was projected to increase by 3.5 percent between 1990 and 2010 . In this inventory we estimated the 1990 and 2008 pump populations based on an assumption that the statewide trend was proportional to the increase in the number of pumps in the county. Input values for engine activity and average engine horsepower were taken from recent government reports which inventory statewide emissions from diesel irrigation pumps . The amount of CO2, N2O, and CH4 emitted was the product of the total amount of diesel fuel consumed by pumps operated in the county and the emission factor for each gas . A GIS database of rice field locations, area‐weighted SSURGO14 soil data and daily weather data from CIMIS15 was compiled for 66 rice fields in Yolo County. The DNDC model was validated against field results from two California‐based field experiments which assessed the affects of residue and water management on CH4 emissions .

Results from the model runs allowed us to generate an emissions factor specific to each management scenario by averaging the simulated CH4 emissions rates across all 66 fields. To account for changes in practice over time,blueberry grow bag size we assumed that 100 percent of the harvested rice area in 1990 was managed according to Scenario A, while in 2008 rice area was divided equally between Scenarios B and C. The percentage of the county’s rice area attributed to each scenario is roughly consistent with statewide estimates for residue burning, residue incorporation, and winter flooding . Finally, the management‐specific emissions factors were multiplied by the area under each management scenario and then summed across each management category to give the total CH4 emissions from rice cultivation for a given year. Further details on residue inputs, fertilizer rates, water management, and model calibration can be found in Sumner et al. and Holst and Buttner . A California‐specific method developed by the CARB was used to estimate emissions from residue burning. This approach is based on studies conducted by the University of California at Davis, which established emissions factors for CO2, N2O, and CH4 for the most commonly burned residues in California . For each gas, the harvested area was multiplied by the fraction of area burned, the crop mass burned per unit area, one minus the residue moisture content, and the corresponding emissions factor for each crop .

In the case of rice, the fraction burned was assumed to have declined from 99 to 11 percent between 1990 and 2008, which is consistent with statewide trends . Carbon dioxide emissions from the addition of limestone and urea were determined by multiplying the amount of each material applied in Yolo County by its default emission factor . The amount of each material was based on county sales records . In Yolo County, total agricultural emissions declined by 10.4 percent between 1990 and 2008 . The primary reason for this generalized decline was a notable reduction in both direct and indirect N2O emissions . Direct N2O emissions were the largest source of emissions during both inventory years, but decreased by 23.1 percent over the study period due to a countywide reduction in the amount of synthetic N fertilizer applied . This reduction in fertilizer use was driven by two important land use trends: a 6 percent reduction in the county’s irrigated cropland ; and a general shift away from crops that have high N rates coupled with an expansion in alfalfa and grape area which require less fertilizer . The large expansion of alfalfa acreage resulted in a moderate increase in the direct N2O emissions from crop residues , but this increase was not enough to offset the overall savings achieved by the displacement of corn and tomatoes. The direct N2O emissions from urine in pasture and manure application ranged between 5 percent and 15 percent of the total direct emissions and showed a small rise over the study period due to a proportional increase in livestock population. Estimates of nitrate lost through leaching and runoff accounted for approximately two‐ thirds of the indirect N2O emissions countywide, with ammonia volatilization responsible for the remaining one‐third .

More than 90 percent of indirect emissions originated from synthetic N fertilizers, while urine and manure from livestock were relatively minor sources. Consequently, the notable decline in indirect N2O emissions was also due to a decrease in the amount of synthetic N applied countywide. In both years, emissions of CO2, N2O, and CH4 from diesel‐powered mobile farm equipment were responsible for 20.0 to 23.0 percent of total agricultural emissions in Yolo County . This category showed little change in emissions over time in 1990 and 69.0 kt CO2e in 2008. This was because an increase in fuel consumption per unit area for several important crops offset the small decline in irrigated cropland . Total emissions from mobile farm equipment were 4 percent lower using the Tier 1 method as compared to estimates generated using the OFFROAD model . However, since the OFFROAD model uses equipment population and hourly usage data to estimate emissions, results from this Tier 3 method could not be used to disaggregate emissions by specific crop category. In both years, emissions of CO2, N2O, and CH4 from diesel‐powered mobile farm equipment were responsible for 20.0 to 23.0 percent of total agricultural emissions in Yolo County . While a reduction in county’s irrigated cropland may have been expected to save fuel and reduce associated emissions, this category showed little change in emissions over time . This was because an increase in fuel consumption per unit area for several important crops offset the small decline in irrigated cropland . Total emissions from mobile farm equipment were 4 percent lower using the Tier 1 method as compared to estimates generated using the OFFROAD model . However, since the OFFROAD model uses equipment population and hourly usage data to estimate emissions,blueberry box results from this Tier 3 method could not be used to disaggregate emissions by specific crop category. Diesel‐powered irrigation pumps emitted approximately 39.6 kt of CO2e in 1990 and 41.0 kt of CO2e in 2008 . This was equal to 11.7 to 13.5 percent of the total agricultural emissions. While irrigated cropland in the county has decreased overall, the amount of land with access to groundwater has continued to expand as new wells are drilled. The small increase in the number of wells operating in the county, therefore accounts for the proportional rise in emissions from irrigation pumping.In Yolo County, CH4 emissions from livestock contributed between 7.8 and 10.5 percent of the total agricultural emissions depending on the inventory year . This is lower than the proportion attributed to livestock statewide, which was more than 50 percent of all agricultural emissions in 2008 . The lower figure for the county essentially reflects the small number of dairy farms operated locally. By contrast, enteric fermentation from pasture‐raised beef cattle was the largest source of CH4 emissions from livestock in both inventory years . Since beef cattle and sheep populations have changed little since 1990, emissions from these livestock types were also relatively stable. While dairy cattle represented only 5 to 12 percent of the county’s cattle in any given year, an increase in the number of dairy cattle from approximately 800 to 2300 animals over the study period resulted in a 20.0 percent increase in total CH4 emissions from livestock . 

Using the Tier 1 method prescribed by CARB, emissions of CH4 from rice cultivation were estimated to increase from 25.9 to 31.2 kt CO2e between 1990 and 2008 . This increase was entirely due to a 20.3 percent expansion in the area under rice cultivation . Estimates generated using the DNDC model showed a larger increase in emissions over the study period ; this Tier 3 method accounted for changes in residue and water management in addition to the increase in cultivated area . Emissions of N2O and CH4 from residue burning contributed 2.0 percent to the total agricultural emissions in 1990 and declined to less than 1.0 percent in 2008, due to the phasing out of rice straw burning in accordance with State regulations . Emissions of N2O and CH4 were relatively small compared to the amount of CO2 emitted during combustion . Most inventory guidelines consider CO2 from residue burning to be a “bio-genic” emission, arguing that it is theoretically equivalent to the CO2 generated during the decomposition of the same crop residue in the soil over the course of the year . Consequently, CO2 from residue burning has been excluded from our inventory total. Emissions of CO2 from lime and urea application each contributed approximately 1 percent to the overall agricultural emissions, and both declined over the study period .One of the main findings of this study is that emissions from agriculture in Yolo County were already on the decline long before the implementation of recent mitigation policies. This trend is largely market‐driven, arising from broad economic factors that are prompting local farmers to shift more of their land to crops which happen to require less N fertilizer and diesel fuel. For instance, many local farmers point to the strong markets for wine grapes and alfalfa, which require fewer inputs as the main factor behind their recent local expansion . These Tier 1 methods do not fully capture the extent to which some growers are reducing fertilizer and fuel use in response to the rising cost and market volatility of inputs, rather than mitigation per se . It should be noted that interviews with Yolo County growers have documented numerous strategies to decrease energy use in cost‐effective ways, but they are often not yet integrated into the cost and return studies for Yolo County crop production .Another important factor contributing to the overall reduction in agricultural emissions was the 8,000 hectare decline in irrigated cropland. This loss of irrigated cropland raises two important questions. First, what type of land use is the cropland being displaced by? And second, how does the carbon footprint of other land uses compare to that of agriculture? Four countywide land‐use trends may explain the decline. Cropland could either be: left fallow, converted to non‐irrigated rangeland, restored to natural habitat, or developed for urban and industrial use. Shifting land use from irrigated cropland to fallow, rangeland, or natural habitat will generally reduce anthropogenic GHG emissions. The same cannot be said for cropland that is developed for urban uses. Urbanization accounted for the loss of about 6,500 acres of agricultural land between 1992 and 2008 . In 1990, emissions sources associated with Yolo County’s urban areas accounted for approximately 86 percent of the total GHG emissions countywide, while unincorporated areas supporting agriculture were responsible for the remaining 14 percent . If calculated on an area‐wide basis the county’s urban areas emitted approximately 152.0 t CO2e ha‐1 yr‐1 . By contrast, our inventory results indicate that in 1990 Yolo County’s irrigated cropland averaged 2.16 t CO2e ha‐1 yr‐1 and that livestock in rangelands emitted only 0.70 t CO2e ha‐1 yr‐1 . This 70‐fold difference in the annual rate of emissions between urbanized land and irrigated cropland suggests that land‐use policies, which protect existing farmland from urban development, are likely to help stabilize and or reduce future emissions, particularly if they are coupled with “smart growth” policies that prioritize urban infill over expansion .While avoided conversion of farmland will help curb emissions from urban sprawl, keeping farmland intact also affords numerous opportunities to mitigate emissions through changes in agricultural practice or by sequestering carbon in soils, perennial crops, or woody vegetation. In considering mitigation options, strategies should not hinder adaptation to climate change, as this could lead to loss of agricultural viability and potential urbanization, a much greater source of GHG emissions per acre.

The lower metal-humus complexes of Andisols in the present study as compared to Andisols from Réunion Island could be associated with the higher annual rainfall and temperature under tropical conditions that accelerated organic matter decomposition. In our study the negative correlation between soil pH and Fep and Alp was observed indicating favorable conditions for organo-metal complex formation under acidic conditions . Tonneijck et al. suggested SOM stabilization in volcanic ash soils in natural Andean ecosystems of Ecuador is through organo-metallic complex formation, low soil pH and toxic levels of Al, and physical protection of SOM in a very large micro-porosity.A place‐based approach for studying agricultural responses to climate change explores a broad set of biophysical and socioeconomic issues related to both greenhouse gas emissions and to adaptation to an uncertain climate. Few such studies exist. Instead, the scientific research on agriculture and climate change has focused on agricultural management practices to reduce the GHG emissions of carbon dioxide , nitrous oxide , and methane , or on the vulnerabilities of different crops to changes in seasonal weather, water supply, pests and diseases,pe grow bag and biophysical factors affecting agricultural production . These are only a few of the aspects necessary for planning for climate change in agricultural regions.

As many jurisdictions in the Western United States are now addressing regional impacts of climate change, there is a need for science‐based exploration tools for scientists, farmers, policymakers, and the general public to better understand the complexity of vulnerabilities and adaptation options for increasing agricultural sustainability in rural landscapes. California’s Climate Change Scenarios Project has focused on determining impacts from plausible climate change scenarios . Use of Global Circulation Models for future climate projections have used two scenarios from the International Panel on Climate Change that are based on story lines for high and low GHG emissions . For agriculture in California, climate change will have impacts on water availability, crop physiology, production , and pest and disease problems , especially for the A2 scenario by the end of this century. Addressing agricultural vulnerabilities and adaptive capacity is part of California’s new statewide climate adaptation strategy. A place‐based vulnerability approach deals with climate change as one of many other long‐range issues such as changes in commodity production, stewardship of natural resources, land use, population growth, and urbanization in a regional system. The capacity of a rural population to adapt with climate change and other uncertainties depends largely on its collective ability to assemble and process information and respond in site‐specific and context‐relevant ways .

Adaptive strategies will require input from many disciplines, including agronomy, ecology, economics, land use planning, and political science. And the involvement of multiple types of stakeholders must inform the assessment and planning process, so that adaptive management can proceed in response to a knowledge base that is continuously developing . The strong science‐policy interface for climate change in California has generated a great deal of agricultural interest in the implementation of the law to reduce statewide GHG emissions, California Assembly Bill 32 , known as the Global Warming Solutions Act of 2006.1 Under AB 32, the state’s GHG emissions are to be reduced to 1990 levels by 2020 through mandatory reporting, emission limits, and reduction measures, as implemented by the California Air Resource Board. It also establishes a goal of 80 percent reduction by 2050 and proposes a cap‐and‐trade policy for GHG emissions. Agricultural GHG emissions will not be included in the cap, but there may be potential for trading carbon offsets from agricultural practices. Senate Bill 375 connects land use planning with implementation of AB 32. It requires a Climate Action Plan for mitigation of GHG emissions in the unincorporated areas of each county in California. This process is engaging farmers and other agricultural stakeholders in detailed accounting of GHG emissions from production and processing practices, and thereby beginning to create greater awareness of vulnerabilities and adaptation options as well.

Yolo County is in the Sacramento Valley of Northern California. It extends westward from the Sacramento River to the Coast Range Mountains . The most important crops are tomatoes, alfalfa hay, wine grapes, and almonds. Upland summer‐dry grasslands and savannas are grazed by cattle. The few small towns and cities have experienced a changing mixture of urban, suburban, and farming‐based livelihoods through the past few decades. In Yolo County, there are approximately 500 farms with an average size of about 500 acres . Many farms produce sales ≥$100,000 per year. Yolo County is ranked 23 by value of sales of California’s 58 counties . Roughly 2 percent of the county’s production is consumed within the Sacramento region . The 653,452 acres of Yolo County are largely agricultural . Important farmland is 57 percent, and livestock grazing land is 24 percent, while urban and built‐up land is only 4.6 percent of the county’s acreage . During the past few decades, there has been a trajectory toward less crop diversification of county acreage, larger farm sizes, but fairly stable markets for commodities . Most commodities are managed with high intensification of agricultural inputs . The number of organic farms, however, is growing. A recent survey showed that many riparian corridors have low scores for soil quality and riparian health , and there is concern about transport of pesticides to the San Francisco Bay delta . Environmental quality is now receiving more attention, with active participation in programs from several agencies. Preservation of agricultural land has been a strong priority in Yolo County, and planning is focused on regional land use guidelines that maintain land in agricultural production and concentrate new development into urban areas . Regions within Yolo County are distinguished by their land forms , proximity to the Sacramento River and Delta , water availability , and the influence of small towns and cities. The regions differ in crop commodities. There is greater prevalence of wine grapes along the river, processing tomatoes in the alluvial plains, and organic fruits and vegetables in an isolated, narrow valley to the north. The regions also have different trends and targets for urban growth, rural housing, and wildlife habitat creation. Flooding along the Sacramento River poses the most significant regional hazard from climate change; water flows will increase by at least 25 percent by 2050 due to a decrease in snow pack in the Sierra Nevada .Climate simulations by Global Climate Models show that mean annual temperature will rise by 1°C to 3°C by 2050, the time frame of this case study . Heat wave days will increase two‐ to three‐fold by 2050. Precipitation is likely to decrease toward the end of the century, depending on the assumptions of each GCM. Hydrological changes suggest, however,growing bags that drought is already increasing and will become more severe and variable with time . Water supply has been considered the most uncertain aspect of climate change for farmers in Yolo County, who rely on groundwater for approximately 30 percent of their supply in a normal water year . It should be emphasized that GCM models are not “predictions,” but rather, are plausible scenarios of climate sequences over a long‐term period. The previous phase of this case study examined possible impacts of increased temperature and decreased precipitation on Yolo County crops . Horticultural crops will likely experience more problems from heat than field crops, due to greater temperature sensitivity of their reproductive biology, water content, visual appearance, and flavor quality . A warmer temperature regime is likely to shift more “hot‐season” horticultural crops, such as melon and sweet potato, into Yolo County’s horticultural “warm‐season” crop mix .

Warmer winter temperatures may allow “cool‐season” crops such as lettuce and broccoli, whose short growth seasons could permit two crops per year, unlike winter grains at present. Expansion of citrus production , and of heat and drought‐tolerant trees, such as olive , are likely options especially because reduction in winter chill hours will reduce flowering in stone fruits, nuts, and grapes . During the past 25 years, crop diversity has decreased in Yolo County . Diversity may increase if farmers find that resilience, especially to extreme events such as heat waves, is enhanced by a species mix that varies in stress tolerance . Forage production for livestock in upland grasslands and savannas may increase with warmer winter temperatures during the winter rainy season, but field experiments with elevated CO2 do not corroborate this expectation . More nitrogen limitation will likely occur under eCO2 . If N‐fixing legumes become more abundant in response to warmer winter temperatures, however, the N supply will increase. Thus, it is unclear if livestock production on these rangelands will actually increase due to climate change, especially in dry years, which require lower stocking rates, earlier animal removal dates, and transport to irrigated, permanent pasture.Pests and diseases are another major uncertainty: warmer temperatures can increase ranges and population sizes, and change the trophic interactions that currently provide biological control of invasive species . At present, no comprehensive compilations from California Department of Food and Agriculture or the National Plant Diagnostic Network exist to show new invasive species to target for a warmer climate . Some literature suggests that it is more efficient to focus on the spread of already naturalized species rather than from new potential invasive species at the importation stage . Yet, the Yolo County Agricultural Commissioner, John Young , notes that several recently arrived pests are becoming severe problems, such as the European grapevine moth in vineyards, spotted wing drosophila on cherries, and Japanese dodder on a wide range of cultivated and wild land plant species. Quarantines are especially difficult for Yolo County because so little of the crop production is consumed within its boundaries, and thus economic hardship occurs unexpectedly for all growers of a particular commodity. Discussions with the Yolo County University of California Cooperative Extension farm advisors indicated special concern for stripe rust on wheat , insect pests on nuts, medfly, corn ear worm on tomato, tomato spotted wilt virus, and earlier activity of perennial weeds such as bindweed . Very recently, alfalfa stem nematode has become a serious pest in the Sacramento Valley, possibly because winter minimum temperatures have reached the lower limit of reproduction for the species . On the other hand, some pests may become less serious; high summer temperatures are likely to reduce the fecundity and survival of the olive fly in this area, which will cause olive yields to increase . Decisions on strategies for adapting to these types of climate change vulnerabilities are not only made by growers. Public institutions, researchers, and non‐governmental organizations become involved in decision‐making by gathering information, stimulating awareness, and generating collective action. At present, California’s strong emphasis on reducing GHG emissions suggests that mitigation and adaptation should be dual components of climate change decision‐making. Some authors have made the case that most categories of adaptation measures have positive impacts on mitigation of GHG emissions . This may be too optimistic. First, agricultural soils may emit more potent GHG in a future CO2‐enriched atmosphere . Second, detailed analysis of crop management may show trade offs between mitigation and adaptation goals. An analysis of benefits of different management options for mitigation and adaptation benefits in Yolo County showed that synergies are often complex . Changes in crop diversity, irrigation methods, fertilizer management, and tillage practices often are more beneficial for either mitigation or adaptation. Rather than change a single practice, major changes in cropping systems will be needed to meet production and mitigation goals. For example, a conventional tomato system with furrow irrigation and knife injection of fertilizer emitted 3.4 times more N2O and had lower yields than an integrated tomato system with drip irrigation, reduced tillage and fertigation on the same soil type . But drip irrigation, unlike furrow irrigation, does not recharge groundwater,leaving farmers more vulnerable to long‐term drought. More comprehensive analysis of these complex relationships is needed.Analyzing changes in past crop acreages in relation to local climate history can provide a set of projections of potential climate‐induced changes in cropping patterns based on how farmers have responded to past climate change.