Análisis de las relaciones entre la precipitación, vegetación y el fenómeno ENOS en las subcuencas Machángara y Tomebamba del río Paute

Abstract

The phenomenon known as El Niño-Southern Oscillation (ENSO) is related to meteorological variables, especially precipitation. In this study, the relationship between ENSO, precipitation and vegetation of the Machángara and Tomebamba sub-accounts is explored. In addition, it seeks to know if there is a relationship between precipitation and vegetation. The data of this study were compiled from the Instituto Nacional de Meteorología e Hidrología (INAMHI), from images of the MODIS satellite and database of indexes of the ENSO phenomenon. This information has a monthly scale and corresponds to the period 2000-2015. Cross correlations were made between the ENSO phenomenon, the Standardized Precipitation Index (SPI) and the Normalized Difference Vegetation Index (NDVI) with a maximum delay of 18 months. The most statistically significant relationships were between the ENSO phenomenon and the SPI, and there were also relationships between the SPI and NDVI. In the two sub-basins, precipitation and vegetation have a similar behavior, however the number of relationships between these variables and the ENSO phenomenon varied. The Machángara sub-basin presented a greater number of relationships, in spite of this, the relationship is similar for the two sub-basins when an El Niño phenomenon occurs when precipitation decreases, the opposite occurs when a La Niña phenomenon occurs. This study could be used as basic information for the prevention of the effects of the increase and decrease of precipitation and for the incorporation of vegetation management plans in the two sub-basins.