Geographic information system as a tool for determining areas for the development of shrimp farming on the south coast of Rio Grande do Sul
In the state of Rio Grande do Sul, as observed worldwide, marine shrimp farming has been expanding since the introduction of the Pacific white shrimp Litopenaeus vannamei. With the potential for productive growth, there is also a real increase in the risks of environmental and socioeconomic impacts, which can directly affect the sustainability of crops. Thus, aiming to achieve a development of the activity through an integrated coastal order, oriented towards the socioeconomic, environmental, spatial and cultural sustainability of the region, the thesis presented here was structured in four chapters. The first had the proposal to identify and characterize the areas destined for the cultivation of marine shrimp located in the southern portion of the Patos lagoon estuary,employing analysis of orbital remote sensing (ETM + / Landsat, Google Earth), aerial (35 mm / ADAR 1000 system), terrestrial (RICOH 500SE) and field outputs, integrating the data in a Geographic Information System (IDRISI Andes). In this chapter, the results showed that the developments were built on coastal fields or in regions of obliterated dunes, regions that are suitable for cultivation. In the second chapter, which was considered a pilot study for the next two chapters, it was proposed to evaluate suitable places for the installation of marine shrimp farming farms, in the region of Ilha da Torotama, RS, considering criteria of fitness and restriction, integrating a final decision-making aid model (GIS).The integrated analysis of the aptitude and restriction criteria for the enterprise showed that the location chosen for this activity has positive aspects. Among them, the location on coastal fields, the proximity of possible consumer markets and local labor, good access, available electricity and local technical support (Federal University of Rio Grande - FURG, Marine Aquaculture Station - EMA) ). As for the third chapter, he aimed to define areas suitable for the development of marine carcinoculture in excavated nurseries, in the region of the lower estuary of Laguna dos Patos (São José do Norte), southern Brazil. As a result, the areas considered most attractive made up a total of 5,300 ha (16.84%), while 14,600 ha (46.78%) had conditions considered good for the activity.Finally, the fourth chapter sought to select areas suitable for marine shrimp farming in the municipality of Rio Grande. As a result of this study, according to the scale of attractiveness (priority 1 to 4), about 2,100 ha. (24.01% of the area considered as suitable) with more attractive characteristics, that is, with excellent conditions; about 3,100 ha. (34.80%) with good conditions; about 3,600 ha. (40.37%) within the recommended range for the activity; and finally, a small fraction, about 70 ha. (0.82%) as suitable areas, but not recommended. From the information obtained in the chapters presented in this thesis work, it was possible to demonstrate the potential of using the GIS technique for the selection of areas suitable for local marine carcinoculture and also that from the scientific material produced here,instruments can be created to assist in making legal management decisions inherent to the activity.