Potencial de uso das terras para sistemas singelos de irrigação na bacia hidrográfica do rio Bodocongó-PB.

Abstract

The objective of this study was to map the lands of the Bodocongó River Basin (BHRB), located on the Paraíba Plateau in the State of Paraíba, with a view to the use of simple irrigation systems, given the region's severe water limitations. The land classification model is parameterized by the following soil attributes: available water (a), slope (e), effective depth (p), drainage (d), fertility (f), sodicity (n), and salinity (s). The Classes, totaling five, are defined by the highest degree of limitation and are represented by Roman numerals (I to V). The Subclasses indicate the nature of the limitations and are represented by lowercase letters designating the restrictive parameters. Descriptive and analytical soil data were obtained from the technical bulletins of the Soil Surveys of the State (1972 and 1978) and supplemented by technical-scientific studies. Based on the altimetry data from the SRTM file and using the free software QGIS, the cartographic base of the BHRB (boundaries and drainage network) and the slope map were created. The soil map was constructed from the boundaries of the 1978 map, with boundary adjustments and the creation of units using Google Earth and field identification and recognition. The BHRB does not have lands classified as Classes I and II, and only has lands classified as Classes III, IV, and V. Therefore, the potential for the implementation of irrigation systems in the basin is viable only in lands classified as Class III, which corresponds to 20.40% of the area (21,909 ha).