Spatial-Temporal Assessment of Annual Water Yield and Impact of Land Use Changes on Upper Ganga Basin, India, Using InVEST Model

The natural environment consists of flora and fauna, providing valuable services for human livelihood, termed ecosystem services (ES). These ES consist of four significant biomes, of which water is one of the subbiomes. Due to anthropogenic activities, visible changes are seen in land patterns, which has a diverse effect on these water bodies. Monitoring these changes plays a vital role in the present-day scenario. The water availability at the upper Ganga basin (UGB) has the potential to develop the state economy by producing hydropower. Hence, the main aim of this work is to estimate the annual water yield and understand the quantity of water yield produced from each Land Use Land Cover (LULC) class in the study area using the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model. The study captures the impact of LULC changes on water yield for three decades from 1985 to 2014. The results are obtained in pixel-level computations, which are incorporated with the spatial variation of parameters in the model application; it shows that the Evergreen needleleaf forest (ENF) plays a significant role in boosting water yield. The outputs obtained by the model are in good agreement with pixel-level formation. This study helps decision-makers take proper steps to increase water yield of the study area and is ideal for application in mountainous regions and other river basins where quality and quantifying ES are critical.