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Researchers at the Centre for Ecological Sciences (CES), Indian Institute of Science (IISc), have found that grazing by livestock leads to lower carbon storage in soil compared to grazing by wild herbivores.

Key Findings of the Study:

• In a study conducted in the Spiti region of the Himalayas and which was published in Global Change Biology, CES researchers found that this difference appears to be due to the use of veterinary antibiotics such as tetracycline on livestock. 
• The researchers said that when released into the soil through dung and urine, these antibiotics alter the microbial communities in soil in ways that are detrimental for sequestering carbon.
• If the carbon stored in soil under livestock can be increased by even a small amount, then it can have a big impact on climate mitigation.
• In a previous study, researchers had shown how grazing by herbivores plays a crucial role in stabilising the pool of soil carbon in the same region.
• The researchers studied soils over 16 years in areas grazed by wild herbivores and livestock, respectively, and analysed them for various parameters including:
  •  microbial composition, soil enzymes, carbon stocks, and the amount of veterinary antibiotics.
• The study states that although soils from the wild and livestock areas had many similarities, they differed in one key parameter called carbon use efficiency (CUE), which determines the ability of microbes to store carbon in the soil. 

News Source: The Hindu