The present study aims to assess the effect of agricultural developments on inter-annual variations in the agricultural Net Primary Productivity (NPP) of selected districts of the semi-arid region of India by using GloPEM model. Advancements in farming practices have been contributing to the increase of net primary productivity, which ultimately leads to increase in the agricultural production. The study shows that increase in the gross irrigated area, fertilizer consumption, use of high yielding crop varieties and adoption of agricultural mechanization in terms of tractors and irrigation pumps have contributed significantly in the increase in agricultural NPP in the semi-arid region of India. The agricultural NPP of the semi-arid region of India has shown a very good correlation with the gross irrigated area (R<sup>2</sup> = 0.668) and fertilizer use (R<sup>2</sup> = 0.701). The anthropogenic factors influencing the agricultural NPP were grouped in 3 major Factor Components (FC) (eigenvalues > 1) as: FC1-nutrients application, FC2-irrigation potential and agricultural mechanization (irrigation pumps and tractors) and irrigated area while FC3-cultivated area and area under high yielding crop varieties. The study showed that most of the semi-arid region of India has a good agricultural production potential which needs to harness by increasing the supply of irrigation water, promoting agricultural mechanization and adoption of integrated nutrient management approach.
Impacts of land conversion and management measures on net primary productivity in semi-arid grassland
