煤炭开采对农田土壤碳储量的影响研究——以典型煤炭开采沉陷盆地为例

Research on the Effect of Coal Mining on Carbon Reserves of Farmland Soil:Taking the Typical Coal Mining Subsidence Basin as a Case

以徐州九里矿区为研究区,选取典型煤炭开采沉陷盆地,通过设计沉陷盆地土壤有机碳库采样方案、实验室土壤有机碳含量测定、构建沉陷盆地土壤有机碳库储量模型以及煤炭开采沉陷前后沉陷盆地内农田土壤有机碳库储量变化的分析,研究了煤炭开采对农田土壤碳储量的影响。研究发现:在煤炭开采沉陷未扰动状况下,沉陷盆地各坡面区土壤有机碳密度均与对照区土壤的有机碳密度相同,煤炭开采沉陷后沉陷盆地各沉陷坡面区土壤有机碳密度随沉陷深度呈现先减小后增大的变化趋势:煤炭开采沉陷前沉陷盆地所在区域内土壤碳库有机碳储量是560.4 t,开采沉陷扰动后沉陷盆地内土壤碳库有机碳储量为530.9 t,比沉陷扰动前减少了5.3%,由此可知,煤炭开采对农田土壤碳储量影响为失碳(碳源)效应。

Taking the typical＇ coal mining subsidence basin of Jiuli mining area of Xuzhou city as the research object to analyze the effect of coal mining on carbon reserves of farmland soil. So, the sampling scheme of subsidence basin soil organic carbon library is designed, the soil organic carbon content is measured in laboratory, the soil organic carbon library of subsidence basin is built, the organic carbon reserves changs of subsidence basin before and after coal mining subsidence are analyzed. The research results show that, the soil organic carbon density of the slope areas is accordance with the one in control area under the condition of coal mining subsidence undisturbed. The soil organic carbon density of the slope areas decreased at first then increased along with the subsidence depth after the mining subsidence. The organic carbon reserves of soil carbon library of the subsidence basin is 560.4 t before mining subsidence,however, after mining subsidence,the organic carbon reserves is 530.9 t. Therefore,the influence of coal mining on the farmland soil organic carbon reserves is carbon loss （carbon source） effect.