Assessing Carbon Sequestration Potential of Check Dams in the Helong Region of the Chinese Loess Plateau

Abstract

Check dams are widely recognized as highly efficacious engineering interventions for preventing soil erosion, and they have been extensively promoted and employed worldwide. However, there is a dearth of comprehensive research on the carbon storage and carbon sequestration potential of check dams, impeding our understanding of carbon fate in sedimentary regions of terrestrial systems. The goal of this study is to evaluate the carbon storage and carbon sequestration potential of check dams within the Helong Region (HLR), utilizing measured data from subcatchments and collected key dam data. The results indicated that the horizontal distribution characteristics of organic carbon (OC) in the seven subcatchments within the Yanhe catchment exhibited a gradually increasing trend from upstream to downstream. The vertical distribution of OC content can be categorized into three patterns: initial decrease followed by fluctuation, initial decrease followed by fluctuating increase, and sudden increase followed by stability. The variation range of OC stored in the dam land was 1.47–598.21 Mg, and there existed a strong quadratic relationship between OC storage and the dam land area. The HLR encompasses a total of 3703 key dams, with a combined storage capacity of 39.89 × 10⁸ m³ and controlling an area of 17951.6 km². As of 2011, the sediment load and OC buried in key dams within the HLR were estimated to be 24.98 × 10⁸ t and 6385.98 Gg, respectively. Assuming complete filling of all key dams, the estimated carbon sequestration potential of the key dams amounted to 6869.41 Gg. The research findings can provide a theoretical foundation for comprehending carbon redistribution and carbon sequestration in the erosion–deposition environment of terrestrial systems.