Carbon stocks in semi-arid pastoral ecosystems of northern Kenya

摘要

Data on carbon stocks in pastoral ecosystems is important for assessing their contribution for offsetting emissions of greenhouse gases through carbon storage. Such data also provides baseline information to determine if pastoral grazing management can be engaged for carbon credit trading. Real and accurate carbon data is scarce. Much of the available data is often based on limited assessment of carbon stocks in a specified range unit, which fails to capture the spatial and temporal heterogeneity that characterizes pastoral ecosystems. In this study, we considered heterogeneity of semi-arid pastoral ecosystems of northern Kenya by aggregating sample results taken during wet and dry seasons and from various landscape types. We found average carbon stocks of 93.01 ± 15.72 tonnes ha?1 across landscape types and seasons. The measured amount of stored carbon is sufficient to have an important contribution in controlling the atmospheric concentration of greenhouse gases; it also indicates a potential to improve pastoralist livelihoods through carbon credit trading. However, more research would be required in order to qualify pastoralists for carbon credits since the data collected in this study is not sufficient to determine the change in carbon storage by grazing practices. In addition, uncertainty in the value of carbon credits needs to be considered to avoid relying on a risky prospect.