About this Research Topic
Current estimates of global soil C, in both inorganic and organic forms, are slightly over 4000 Pg C, which is more than five and a half times the amount of carbon currently in the atmosphere or, put differently, is equivalent to about 400 times the amount of C released yearly to the atmosphere by fossil fuel consumption or cement manufacture. Therefore, even a small drop, of the order of a percent, of the amount of carbon contained in soils, due to a rise in ambient temperature and a resulting stimulation of microbial metabolism, could lead in the long run to a very noticeable increase in atmospheric C and a devastatingly positive feedback to climate change. Conversely, a small increase in the amount of carbon held in soils, brought about for example by a shift in agricultural or forest management practices, could compensate, at least partially, the increase in atmospheric CO2 caused by human activities. Aside from its significance to climate change, the amount of carbon contained in soils also influences their architecture, and therefore their ability to transmit and retain water, which has important consequences in terms of mitigating floods, providing adequate moisture for plants, and recharging aquifers.
Because of this crucial importance of soil carbon storage to a range of issues of great concern to human societies, researchers have devoted a significant amount of attention to the topic over the last 2 decades. Progress has been made relative to a number of aspects, but many difficult questions remain unanswered at this stage, for example concerning the temperature dependence of the fate and dynamics of soil organic matter, the practical problems that priming may pause to any efforts to store more carbon in soils, the impact of inorganic carbon compounds on the dynamics of soil carbon storage, or the relative potential of different agricultural or forest management practices to preserve carbon stocks or increase them in the future.
In this general context, the objective of the present Research Topic is to serve as an outlet for manuscripts that address one or several of the many facets of the storage of carbon in soils. The research described in these manuscripts can be experimental (in laboratory or field settings), involve extensive monitoring, or be based on computer modeling. Of special interest are manuscripts that attempt to elucidate the complex physico-chemical and microbiological processes that control the storage of carbon in soils, as well as the environmental factors and land management strategies that influence them. Manuscripts dealing specifically with the coupling of the carbon and iron cycles in soils should be directed to a separate Research Topic that is currently accepting submissions on this subject.
Manuscripts submitted to this research topic can have one of a number of formats: research articles, extended reviews, mini-reviews on specific topics, perspective articles, or short opinion pieces. The goal of each of these types of articles, and especially of the last two, is to stimulate a healthy debate on where the research is at the moment, and where it should head in years to come, to ensure that we meet the very pressing deadlines facing us with respect to the soil carbon storage issue.
Keywords: carbon sequestration, soil organic matter, greenhouse gas production, dynamics, climate change
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.