土地利用方式和地形对半干旱区土壤有机碳含量的影响

Effects of Land Use Type and Terrain on Soil Organic Carbon (SOC) Content in Semi-arid Region

以内蒙古赤峰市敖汉旗为研究对象,以实地调查数据为基础,结合土地利用方式与地形的变化,对敖汉旗0～100 cm深度土壤有机碳含量的空间分布特征进行了研究,旨在对地区碳储量的估算和科学利用土地资源起到积极的借鉴作用。结果表明,敖汉旗土壤有机碳含量在0～100 cm深度的土壤剖面内的变化范围为0.23～20.71 g/kg,主要集中在40 cm以上土层,且随着土层深度的增加土壤有机碳平均含量逐渐降低;各土地利用方式下土壤有机碳含量均表现为:林地>农地>草地。土壤有机碳含量主要富集在高海拔区的平缓地段;受土壤侵蚀的影响,当坡度>10°后,不同土地利用类型的有机碳含量均显著降低。

In this study, Aohan county in Chifeng of Inner Mongolia was collected as the study area, the spatial distribution of soil organic carbon (SOC) content at 0-100cm was studied based on soil survey data and considering the changes of land use type and terrain in order to estimate carbon storage and to rationally use land resources. The results showed that SOC content was within 0.23-20.71g/kg, SOC content was mainly concentrated in 0-40cm soil, SOC content decreased gradually with increasing soil depth and SOC contents exhibited in an order of woodland > farmland > grassland. SOC was mainly stored in the flat area of high altitude. SOC content of different land use types were significantly reduced when slope>10°due to soil erosion.