A procedure to estimate soil erosion impact on soil productivity in Uruguay

Abstract

USLE and RUSLE were reasonably adjusted and validated in Uruguay to predict soil erosion. Nevertheless, soil mass losses should be expressed in terms of soil productivity or land value losses, in order to guide soil management decision making, and assess its impact in productive and economic terms. procedures to do the last, cited in the literature (like EPIC), are not validated in Uruguay, and express soil productivity in terms of crop productivity. Being extensive animal production, based on pastures grazing, the main agricultural activity in Uruguay, soil productivity loss due to soil erosion should be better expressed in these terms. Uruguay possesses a system of soil productivity assessment an individual farm level, that expresses soil potential animal production of beef and wool based on natural pastures grazing, as percentage of the national average. This system was developed to guide land taxing, and became so widely accepted that guides the land market. The system recognizes variations in its Productivity Index (PI) due to past soil erosion. The present work had two objectives. The first one was to quantify, inside the system, the relationship between degree of erosion and PI. The second one, was to develop a procedure to transform soil erosion rate estimates into PI loss estimates, and to give examples of its use. The next future step will be to investigate the relationship between PI and land market price.