Civil, Structural, and Environmental Engineering

Dr. Karen Silva Castro

Universidad Tecnica Particular de Loja
Ecuador

Abstract Title: Water Balance and Soil Moisture Deficit of Different Vegetation Units under Semiarid Conditions in t

Biography:

Master Karen Silva studied Civil Engineering at the Universidad Técnica Particular de Loja and graduated with a master's degree in water resources in 2019. She has worked as a hydrosanitary designer and hydrologist in several private and public companies in projects executed nationwide in Ecuador.

Research Interest:

Water availability in semiarid regions is endangered, which is not only due to changing climate conditions, but also to anthropogenic land use changes. The present study analysed the annual and monthly water balance (WBC) and the soil moisture deficit (Ds) for different vegetation units under semiarid conditions in the Andes of southern Ecuador, based on limited meteorological station data and field measurements (soil samples). To calculate crop evapotranspiration (Etc) the Blaney-Criddle method was applied, and the specific crop factor (Kc) included, because only temperature (T) and precipitation (P) data were available, By means of the soil samples the water retention capacity (RC) of different soil types present in the study are were estimated, which, in combination with WBc, provided reliable results respective to water surpluses or deficits for the different vegetation units. The results indicated highest Ds for cultivated areas, particularly for corn and sugarcane plantations, where annual deficits up to – 1377.5 mm ha-1 and monthly deficits up to -181.1mm ha-1 were calculated. Natural vegetation cover (scrubland, forest and paramo), especially at higher elevations, did not show any deficit throughout the year (annual surpluses up to 1279.6mm ha-1; monthly surpluses up ti 280.1mm ha-1). Hence, it could be concluded that the prevailing climate conditions in semiarid regions cannot provide the necessary water for agricultural practices, form which reason irrigation is required. The necessary water can be supplied by areas coved by natural vegetation, but these areas are endangered due to population growth and the associated land use changes.