Determination of Topographic Wetness Index for “La Mina” catchment in the Ecuadorian coastal region.

Abstract

The Topographic Wetness Index (TWI) can help determine the spatial distribution of plant species richness, soil pH, groundwater level, and soil moisture in a watershed. In this work, the TWI for the La Mina basin on the Ecuadorian coast is estimated by evaluating the influence of different calculation methods and the resolution of the input on the results. We proceed from digital elevation models (DEMs) with computational tools such as Quantum GIS (QGIS), and the TOPMODEL hydrological model. It is concluded that the content and resolution of the information of a DEM have an influence on the results of TWI.