DETERMINACIÓN DE LA EROSIÓN ACTUAL Y POTENCIAL DEL TERRITORIO DE CHILE MEDIANTE TÉCNICAS DE GEOMÁTICA, TELEDETECCIÓN Y SIG. Juan Pablo Flores, Eduardo Martínez, Marión Espinosa, Pedro Muñoz Centro de Información de Recursos Naturales. Chile. Dedicado a Patricio Lara Greene†. ABSTRACT The main causes of soil erosion are still inappropriate agricultural practices, deforestation, overgrazing and land use change. Soil erosion is a widespread problem throughout Chile. This study determines current and potential soil erosion for territory of Chile through the use of two qualitative models using geomatics and remote sensing techniques. The current soil erosion mapping was obtained using an integrated method based on GIS and image processing LANDSAT TM. The analysis includes land cover and soil maps, contours, hydrography, slope, aspect and georeferenced information of the soil erosion and land use. The potential erosion mapping was obtained with an empirical model based on an integrated analysis of soil characteristics, climate and topography that are related in two main components, soil erodibility and erosivity ram. The study area covers 75 million hectares and has two working geographics scale depending on the availability of information (1:50,000 and 1:250,000). The result study show an area of 36.8 million hectares, equivalent to 49.1% of the country has some degree of soil erosion. The sectors with the greatest soil erosion problems are the regions of Coquimbo with 84%, Valparaíso, 57%, and O`Higgins Region 52% of degraded soils. The largest soil erosion problems affecting agriculture and forestry sector are concentrated in the regions of Coquimbo to Maule, where human action and indicators of climatic aggressiveness, and watershed geomorphology significantly affect the characteristics of runoff and as such are of great interest in hydrologic analyses y the water and soil conservation. Key words: soil erosion risk, spectral index, remote sensing, teledetection, soil erodability, rainfall erosivity. INTRODUCCIÓN Nuestro país, por su particular condición fisiográfica y sus características climáticas, está altamente expuesto a ser afectado en vastas áreas por el proceso de erosión hídrica. Los primeros testimonios de la pérdida suelo en Chile se remontan a los estudios de Claudio Gay, Benjamín Vicuña Mackenna, R.E McLure y Federico Albert quienes informaron sobre la enorme fragilidad de los suelos de Chile y las consecuencias que las malas prácticas silvoagropecuarias tendrían para las futuras generaciones. Estudios contemporáneos, nos ratifican la misma situación preocupante de los niveles de erosión (Soto, 1997; Pérez & González, 2001; Bonilla et al., 2009), lo que podría dificultar propósitos como el de convertir a Chile en potencia agroalimentaria. El abordaje de esta problemática demanda una cuantificación actual y potencial de la erosión en Chile, pero los estudios de degradación de recursos naturales, erosión y 21