Tropical grasslands as potential carbon sink

Abstract

Grasslands, an important natural resource, include a wide variety of ecosystems and cover around 26% of the world’s total land area. Soils of grassland store a large amount of carbon, with global carbon stocks estimated at about 343 Pg C. Besides, grasslands play a significant role in climate change mitigation through sequestering carbon from the atmosphere. Globally, the estimated carbon sequestration potential of soils lies between 0.4 and 1.2 Pg C per year, of which 0.01-0.30 Pg C per year is from grasslands. But grassland per se does not result in a carbon sink or sequestration. Carbon sequestration can be enhanced in grasslands by adopting appropriate management practices like controlled and improved grazing management, sowing favourable forage species, fertilizer application and irrigation, restoration of degraded grasslands, etc. However, there are certain limitations/constraints that hamper adopting of those practices, enhancing carbon sequestration in grasslands. The limitations include incessant degradation of grasslands, climate change, paucity of genuine data on carbon stock of grasslands, particularly from developing countries, etc., which need to be resolved in the future.