Coastal planning and land use of marine shrimp farming in southern Brazil

The study area lies in the lower estuary of Lagoa dos Patos in the city of Rio Grande (Lat/Long: 32°02’16.39”S/52°06’28.41’’W), Rio Grande do Sul state, Brazil, comprising a total area of approximately 280,000 hectares (ha). To select areas suitable for marine shrimp farming, data processing and digital modeling were conducted with the Idrisi Andes Edition® GIS software using freely available images. Additionally, the most commonly used criteria, socioeconomic factors, infrastructure and logistics, soil, climate, topography, and water availability, were used. To improve upon the obtained results from a classification based exclusively on the distinction between restricted and suitable areas for aquaculture, a suitability score for each criterion analyzed was created, and distances from suitable sites were measured. According to the suitability rating (prioritized from 1 to 4), 2,100 ha (24.01% of the area) were considered suitable with excellent conditions; 3,100 ha (34.80%) were considered good; 3,600 ha (40.37%) were marginally suitable; and, finally, a small fraction of 70 ha (0.82%), was considered acceptable but not recommended. This study has demonstrated the potential of GIS to support the selection of areas suitable for marine shrimp farming.