Estimation of sediment production by soil management practices in a transboundary basin

Abstract

The Catamayo (in Ecuador)-Chira (in Peru) transboundary basin in its lower part has the Poechos multipurpose reservoir, which is essential for the economic and productive development of northern Peru. However, due to inadequate soil management in the basin, the reservoir is accumulating a high sediment load. The decision made by the reservoir administration was to raise its elevation, without considering working alongside farmers in the basin, proposing alternatives for sustainable soil management. In this context, the objective of this study was to estimate the sediment export by simulation soil management and conservation practices, using the sediment delivery ratio module (SDR) in the InVEST 3.9.0 software, to suggest adequate practices for the conditions of the soil watershed. Sediment export based on land use change over the last 30 years was also modeled. This study contributes as an instrument for the integrated water resources management (IWRM), which allows a balance between the users of the water resources (beneficiaries) and suppliers, who have their soils degraded. Thus, IWRM can go from being a simple intention, to a key tool to promote policies and international agreements, toward the generation of clean and abundant water for both countries. At the same time, it favors the management and conservation of the soil of the basin and its related resources, to maximize economic and social welfare in an equitable manner for both countries.