In 2010, the total production of white shrimp Penaeus vannamei from world aquaculture was 2.7 million tons with a first sale value of U$ 11 billion . The rapid development of shrimp farming in many countries is a phenomenon of the last three decades as a result of industrial transformation and intensification of production patterns . Shrimp farming has been a significant agro-based economic activity . This multimillion dollar industry plays an important role in the economic development of many tropical and sub-tropical countries because of the high economic returns . However, there is evidence that sustainable production is limited partly by the carrying capacity of the coastal ecosystems supporting aquaculture . Additionally, the rapid growth of this Indus- try in an unregulated and uncoordinated way has led to a number of environmental, technical, economic and social problems, which have been widely reported in international literature .
The conversion of sensitive coastal land, including mangroves, into shrimp ponds in many locations and periods, has been principal criticism to shrimp farming Industry . In areas of intense shrimp farming, dis- charge waters from one farm mixed with supply waters used by neighboring farms, have resulted in pollution between farms and the spread of disease between shrimp populations . However, different shrimp culture technologies have different environmental impacts. Extensive systems requiring large land areas have contributed most to mangrove clearance, grow bucket while intensive systems have contributed more to pollution problems, through high stocking densities and feed and chemical inputs . Brazil is the third largest producers of farmed white shrimp in Latin America. The Brazilian production was estimated at 70,000 tons with an estimated value greater than U$ 280 million in 2010 . In Brazil, semi-intensive and intensive shrimp farming began during the 1980s with introduction and culture of white shrimp P. vannamei.
The northeast region of Brazil is responsible for around 97% of the national shrimp production . The fast development of shrimp farms in this region has given rise to concerns about specific environmental legislation for the activity, environmental pollution and conflict with rural population. In the early 2000s, Brazilian shrimp aquaculture was responsible for the employment of 50,000 people , reducing the pressure against the development of the activity. However, the industry has been suffered a severe collapse due to disease outbreaks in 2003 . This fact has caused a drastic reduction in the number of jobs, which has strengthened the movements against the shrimp industry. In Brazil, the total area dedicated to shrimp farming approximates 18,500 ha of which 5750 ha are located in Ceará State . The estuary of Jaguaribe river has the largest number of shrimp farms in the state of Ceará. In this estuary, the shrimp pond area increased from 820 ha in 2000 to 1640 ha in 2006 . However, information about the positive or negative impacts of shrimp farms in this region is unknown. This article documents the dimensioning of the production area of shrimp farms using satellite images and geoprocessing techniques, and analysis of shrimp production, technical, economic, social and environmental aspects of shrimp farms in the estuary of Jaguaribe river. Shrimp aquaculture production consists mainly of white shrimp Penaeus vannamei and it takes place almost exclusively in earthen ponds. This analysis focuses on shrimp production in ponds with particular attention to the cultivation and harvesting phases in the production cycle. The cultivation phase includes post larvae stocking, feeding and pond water exchange.
A number of farming processes in these phases have potentially significant impact on the environment. The processes of pond treatment, inlet water treatment, feeding, water ex- change, and final water discharge and sediment dredging were observed and described. The methodology was based on field observations, interviews, and analysis of secondary data . A survey carried in the period 2010-2012 involved visits to all shrimp farms. Interviews were conducted using a semi- structured questionnaire. Interviewees included farm owners or managers, traders, processing firms and hatchery managers and government officials. Data analysis was based on field observations, interview transcriptions, and external sources including official documents, external sources and academic literature on the subject.All shrimp farms were visited to collect information about the macro-economic benefits and problems of shrimp aquaculture. The macro-economic benefits include the creation of direct formal jobs, seasonal jobs, indirect for- mal jobs including hatcheries and post-harvest, earning of foreign exchange, diversification of the economy, stimulation of backward and forward-linked sectors, in-flow of direct investment and technological transfer.