Spatio-temporal variability analysis of evapotranspiration, water use efficiency and net primary productivity in the semi-arid region of Aravalli and Siwalik range, India

Sustainable and effective water use management is a global challenge for optimum productivity for all types of vegetation cover. Evapotranspiration (ET) is one of the key components determining the soil moisture conditions ensuring the water availability for vegetation in an area. The present study provides a strong basis for existing water conditions in the study area using evapotranspiration as an important tool. There is a large variability in evapotranspiration during the different months of the year 2022-23 as well as over a long period of study ranging from the year 2001 to 2022. Water use efficiency in the study area is 0.32 g C/kg H2O which is less than half that of China and USA. The study showed an increasing trend of net primary productivity (NPP) and water use efficiency (WUE) during 2001-22. The comparatively lower WUE and NPP in comparison with global average are of great concern for a semi-arid region, which is also India's leading agricultural producer state.