Use of P-Index in a waterbasin by geoprocessing techniques

Fabíola Lopes Gustavo H. Merten Melissa Franzen Elvio Giasson Fernanda Helfer Luis F. A. Cybis About the authors

Due to problems caused by eutrophication of lakes and reservoirs, the identification of phosphorus source areas is important for planning the control of agriculture-related water pollution. This study applied a method designed to identify these phosphorus source areas, called P-Index, which is based on combining data layers related to soil phosphorus availability and phosphorus transport processes. The method was used for studying the Salto Reservoir waterbasin, in São Francisco de Paula, in the State of Rio Grande do Sul, Brazil. Data related to phosphorus availability, intensity of transport processes, and distance to waterways were combined to yield a map of phosphorus contribution classes, which showed that almost the entire study area was considered to have low phosphorus contribution potential. A few small areas, corresponding to potato and garlic fields that received heavy chemical fertilization, were classified as having high phosphorus contribution potentials.

eutrofication; land use; Geographic Information System

Departamento de Engenharia Agrícola - UFCG Unidade Acadêmica de Engenharia Agrícola, UFCG, Av. Aprígio Veloso 882, Bodocongó, Bloco CM, 1º andar, CEP 58429-140, Campina Grande, PB, Brasil, Tel. +55 83 2101 1056 - Campina Grande - PB - Brazil