Erosion scenarios in the Coyolate River watershed

Abstract

The Coyolate river basin is of economic and ecologic importance for Guatemala, where the crops that contribute most to the national GDP are produced: sugar cane, corn, bananas, and coffee, beans, and rubber among others.  The study generated three water erosion scenarios using four levels of zero to light, moderate, strong, and very strong erosion, corresponding to erosion rates of less than 10, 10 to 50, 50 to 200, and greater than 200 tons per hectare per year. The intensity of use of the soils in the basin was determined by comparing their use capacity with their current use using the USLE model for calculating water erosion. The scenarios presented the following coverages: a) 96% agriculture, 1.5% forest and 2.5% other uses; b) 65% agriculture, 28% forest and 7% other uses; and c) 69% agriculture, 29% forest and 2% other uses. The study concluded that one of the main causes of water erosion in Coyolate river basin is the inadequate use of its soils without considering their use capacity and geomorphological characteristics. It was found that even if the area for agriculture is increased, adequate use distribution would generate less water erosion. To mitigate water erosion in the watershed, its management must be improved, adapting the use of its soils, and implementing conservation practices.