|Ranieri, S B L - UNIV. SAO PAULO, BRAZIL|
|Sparovek, G - UNIV. SAO PAULO, BRAZIL|
|Demaria, I - UNIV. SAO PAULO, BRAZIL|
Submitted to: International Soil Conservation Organization Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: May 24, 1999
Publication Date: N/A
Technical Abstract: Several land use planning studies in tropical regions use erosion estimation as an indicator for land degradation. The objective of this work is the development of USLE and Water Erosion Predict Project (WEPP) application technology for a sugarcane-growing watershed in Southeast Brazil. The models will be compared in relation to outputs, complexity, application cost and GIS compatibility. The study area is the Ceveiro Watershed (2,000 ha) located in the state of Sao Paulo in southeast Brazil. The first part of the study has been developed in a sub-watershed (86 ha) with representative conditions for the whole area. Data collection for USLE application consisted of soil survey, land use and management mapping, slope and aspect calculation and climate data set analysis. Soil samples were collected in 89 sampling points and analyzed for chemical and texture attributes. Land use was mapped based on aerial photographs. Management practices were assessed by landowner interviews. Slope and aspect were calculated from altitude contour maps using GIS technology. All data were georeferenced and the USLE parameters were calculated using GIS formulas. Average soil loss for the watershed was estimated at 39 Mg.ha-1.y-1. The input data for WEPP application are being prepared, and an interface file builder program to convert vector UTM georeferenced slope data in single Overland Flow Element (OFE) and multiple OFE WEPP slope files will be developed for the WEPP Hillslope version. This program will also write composite management and soil files for multiple OFE hillslopes and re-georeference WEPP output files allowing GIS importation.