Degraded Land Restoration in Reinstating CH ₄ Sink

摘要

Methane (CH_(4)), a potent greenhouse gas, contributes about one third to the global green house gas emissions. CH_(4)-assimilating microbes (mostly methanotrophs) in upland soils play very crucial role in mitigating the CH_(4)release into the atmosphere. Agricultural, environmental, and climatic shifts can alter CH_(4)sink profiles of soils, likely through shifts in CH_(4)-assimilating microbial community structure and function. Landuse change, as forest and grassland ecosystems altered to agro-ecosystems, has already attenuated the soil CH_(4)sink potential, and are expected to be continued in the future. We hypothesized that variations in CH_(4)uptake rates in soils under different landuse practices could be an indicative of alterations in the abundance and/or type of methanotrophic communities in such soils. However, only a few studies have addressed to number and methanotrophs diversity and their correlation with the CH_(4)sink potential in soils of rehabilitated/restored lands. We focus on landuse practices that can potentially mitigate CH_(4)gas emissions, the most prominent of which are improved cropland, grazing land management, use of bio-fertilizers, and restoration of degraded lands. In this perspective paper, it is proposed that restoration of degraded lands can contribute considerably to improved soil CH_(4)sink strength by retrieving/conserving abundance and assortment of efficient methanotrophic communities. We believe that this report can assist in identifying future experimental directions to the relationships between landuse changes, methane-assimilating microbial communities and soil CH_(4)sinks. The exploitation of microbial communities other than methanotrophs can contribute significantly to the global CH_(4)sink potential and can add value in mitigating the CH_(4)problems.