Rangelands as Carbon Sinks to Mitigate Climate Change: A Review

Abstract

Rangelands cover large areas in the United States and across the world and are natural carbon sinks which if properly managed and maintained can sequester substantial amounts of atmospheric carbon dioxide in the form of soil organic carbon and mitigate climate change. Varied climatic conditions impact carbon sequestration at the arid and semi-arid ecological sites on rangelands. Best management practices, site-specific policies and technological options are important approaches to manage these ecosystems to mitigate the impact of current climate variations. There are a number of co-benefits associated with management of rangelands for carbon storage, these include; improve soil quality and resilience, agronomic productivity, advancing global food security and restoring ecosystem diversity. Also, the non-equilibrium model is proposed for use on these xeric sites of rangelands since it better reflects the ecological dynamics that impact carbon sequestration and as such policies should be embodied this understanding. More studies are needed on the ecological dynamics, and factors that affect soil carbon sequestration process and mechanisms on arid and semi-arid environments as well as the soil organic carbon residence time so as to better our understanding of these regions. The voluntary carbon market was a good approach for stimulating carbon sequestration on rangelands, however the causes of failure should be revisited, addressed and necessary amendment to policies made that will be the driving force towards environment restoration and conservation. Some of the obvious challenges and opportunities with regards to efficient use of rangelands as carbon sinks to mitigate as well as adapt to climate change are discussed in this paper.