TENDENCIA ANUAL DEL CAUDAL DE SALIDA, EN REFERENCIA AL CAUDAL ECOLÓGICO EN LA MICROCUENCA APACHETA / AYACUCHO / PERÚ, DEL 2000 AL 2018

Decreasing outflow observed in the Apacheta micro-basin during the period 2000-2018, has a direct impact on the water storage of the Cuchoquesera dam, with subsequent negative impacts on local water provisioning for human consumption and agricultural activities – whose demand has already surpassed the supply capacity of the reservoir-as well as the ecological volume needed for ensuring the proper functioning of ecosystems along the catchment. In the long term, this problem may be intensified by the effects of climate change. The objective of this study was to assess the annual trend of the Apacheta micro-basin discharge and forecast future values, in comparison to its ecological flow of 2.24 m³/s and the sensitivity towards adequately satisfying the different demands over time. For this, we combined hydro-meteorological data and remote sensing information with the PRMS-IV hydrological model. Our results indicate that, upon continuing the annual outflow trend, a decrease of 46.1% and 56.1% below the ecological flow could be expected for the next 5 and 10 years, respectively. At the regional and national government levels, timeframes of 5-10 years are typically considered for planning purposes, in that sense, our results have the potential to guide decision-making processes towards mitigating water-scarcity risks.