Two-thirds of India’s terrestrial ecosystems vulnerable to drought, says study
New Delhi: Nearly two-third of the India’s terrestrial ecosystems is not resilient to drought, a new study has revealed. It also says that inability of ecosystems to tolerate water-limited conditions may pose a serious challenge in terms of carbon sequestration, crop production, and food security.
The study by Ashutosh Sharma and Manish Kumar Goyal of the Indian Institute of Technology, Guwahati was published in international journal Wiley: Global Change Biology earlier this month. It facilitates understanding of how ecosystems in different regions of India respond to hydroclimatic disturbances like droughts.
For the study, the researchers compared the response of terrestrial net primary productivity (NPP) to hydroclimatic disturbances in India at different scales (at river basins, land covers, and climate types) to examine the ecosystems’ resilience to such adverse conditions. NPP is defined as the net amount of carbon assimilated by plant by taking photosynthesis and respiration into account.
The study noted that recent researches have indicated that there is an increasing trend in hydroclimatic disturbances like droughts, which are anticipated to become more frequent and intense under global warming and climate change.
“Under the scenarios of increasing trend in drought severity and frequency during the recent decades and projected future possible reductions in monsoon-related rainfall in the country, ecosystems in India will face many hydroclimatic disturbances such as droughts,” the study said.
The non-resilient characteristics of most river basins suggested that NPP would decrease under such conditions in the future, it added.
“Only six river basins of 22 river basins were resilient to climatic disturbances in the study duration including Indus and Brahmaputra basin and this highlights the need for taking sufficient adaptation measures to ensure sustainability of ecosystems,” Goyal told Mint.
He emphasised that it is for the first time that the ecosystem resilience map of India from 2000-14 has been prepared using high resolution remote sensing satellite data for all river basins.
“Our results facilitate the identification of the most sensitive regions in the country for ecosystem management and climate policy making, and highlight the need for taking sufficient adaptation measures to ensure sustainability of ecosystems,” Goyal added.
As per the study, these sensitive regions are the central and eastern parts of the country.
The study warned that the “inability of ecosystems at different scales to tolerate the water-limited conditions may pose a serious challenge in terms of carbon sequestration, crop production, and food security”. This is significant for a country like India which has over 1.2 billion people to feed.