Soil Carbon Sequestration Potential of Terrestrial Ecosystems: Trends And Soil Priming Effects

Carbon sequestration in the terrestrial ecosystems by forest and agricultural management activities is being considered the best sustainable method to diminish the increasing concentration of atmospheric carbon dioxide (CO2). This paper presents soil carbon sequestration potential of terrestrial ecosystem and the concept of soil priming effect. According to forest survey of India, the carbon stock of Indian forests increased at the rate of 0.3% as compared to the previous assessment, i.e., from 2017 to 2019. Indian forests soils are a reservoir of 7124.6 million tonnes of carbon and they still have high potential to store more carbon. As per soil carbon 4 mille concepts, India must intensify the process of afforestation, land restoration, and agricultural management practices to increase the soil carbon storage, i.e., up to 0.4%. However, organic manure amendments or a fresh supply of carbon substrates via. rhizodeposits into the rainfed or irrigated lands changes the microbial communities and may decompose the already stored soil carbon, i.e., positive priming effect. Thus, accurate measurement of soil organic carbon (SOC) content in various types of ecosystems like forest, agricultural land, desert, agroforest, and plantation is still crucial to ascertain how much they can help to reduce the increasing concentration of atmospheric CO2.