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arXiv · 2212.00457

Warming inhibits Increases in Vegetation Net Primary Productivity despite Greening in India

Ripan Das·Rajiv Kumar Chaturvedi·Adrija Roy·Subhankar Karmakar·Subimal Ghosh
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Abstract

India is the second-highest contributor to the post-2000 global greening. With satellite data, here we show that this 18.51% increase in Leaf Area Index (LAI) during 2001-2019 fails to translate into increased carbon uptake due to warming constraints. Our analysis further shows 6.19% decrease in Net Primary Productivity (NPP) during 2001-2019 over the temporally consistent forests in India despite 6.75% increase in LAI. We identify hotspots of statistically significant decreasing trends in NPP over the key forested regions of Northeast India, Peninsular India, and the Western Ghats. Together, these areas contribute to 31% of the NPP of India (1274.8 TgC.year -1). These regions are the warming hotspots in India. Decreasing photosynthesis and stable respiration, above a threshold temperature, are the key reasons behind the declining NPP. Warming has already started affecting carbon uptake in Indian forests and calls for improved climate resilient forest management practices in a warming world.

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Ripan Das, Rajiv Kumar Chaturvedi, Adrija Roy, Subhankar Karmakar, Subimal Ghosh. 2022-12-01. Warming inhibits Increases in Vegetation Net Primary Productivity despite Greening in India. https://arxiv.org/abs/2212.00457

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