Cálculo del balance hídrico del suelo y el déficit del agua en una cuenca semiárida en el Sur del Ecuador

Abstract

Abstract:Vegetation cover and land use are important factors for the local and regional water availability, besides the precipitation amounts and evaporation rates, especially in semiarid regions. The anthropogenic land cover change can alter the rainfall-runoff processes, and therefore the water storage in the soils, which leads to an enhanced water use in the agricultural sector because irrigation systems must be implemented to guarantee food production. However, the irrigation systems are generally poorly managed, which additionally enhance the water consumption and restrict the local water availability. The present study estimated the monthly soil water reserve, or deficit, in a semi-arid basin in the Andes of southern Ecuador, based on available 10-year data sets of air temperature and precipitation, as well as on filed measurements. By means of the climate data, precipitation amounts, and the specific crop evaporation (ETc) was calculated, applying the monthly Blaney-Criddle equation in combination with the crop coefficient (Kc). The water retention capacity of the different soils was determined by means of the hydrometer method.