Impact of land use conversion on soil organic carbon stocks in an agro-pastoral ecotone of Inner Mongolia
Impact of land use conversion on soil organic carbon stocks in an agro-pastoral ecotone of Inner Mongolia
复制标题
内蒙古农牧交错带土地利用转换对土壤有机碳储量的影响
DOI：
10.1007/s11442-017-1417-1
复制
发表时间：
2017-09
影响因子：
4.9
通讯作者：
Wei Zhao;Zhongmin Hu;Shenggong Li;Q. Guo;Hao Yang;Tonghui Zhang
中科院分区：
文献类型：
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作者：
Wei Zhao;Zhongmin Hu;Shenggong Li;Q. Guo;Hao Yang;Tonghui Zhang
陆地生态系统土壤有机碳储量随土地利用方式的不同而存在显著差异。内蒙古农牧交错带是草原、森林、农田并存的地区。利用文献资料和野外调查资料，比较了3种生态系统SOC储量及其垂直分布。结果表明，草地土壤有机碳储量最大，分别是林地和农田的1.5倍和1.8倍。相对于0-100 cm土层的土壤有机碳储量，草地在20 cm土层的土壤有机碳储量占40%以上，林地和农田在20 cm土层的土壤有机碳储量占30%以上。禁牧≥20年后，放牧草地土壤有机碳储量显著增加。保护性耕作显著增加了农田土壤有机碳储量，尤其是0-40 cm土层。林分年龄、树种和森林类型对研究区森林有机碳储量没有明显影响，可能是由于林分年龄较小。研究结果表明，在干旱半干旱地区实施退耕还林等生态工程时，应考虑土壤碳流失的影响。
Soil organic carbon (SOC) stocks in terrestrial ecosystems vary considerably with land use types. Grassland, forest, and cropland coexist in the agro-pastoral ecotone of Inner Mongolia, China. Using SOC data compiled from literature and field investigations, this study compared SOC stocks and their vertical distributions among three types of ecosystems. The results indicate that grassland had the largest SOC stock, which was 1.5- and 1.8-folds more than stocks in forest and cropland, respectively. Relative to the stock in 0–100 cm depth, grassland held more than 40% of its SOC stock in the upper 20 cm soil layer; forest and cropland both held over 30% of their respective SOC stocks in the upper 20 cm soil layer. SOC stocks in grazed grasslands were remarkably promoted after ≥20 years of grazing exclusion. Conservational cultivation substantially increased the SOC stocks in cropland, especially in the 0–40 cm depth. Stand ages, tree species, and forest types did not have obvious impacts on forest SOC stocks in the study area likely due to the younger stand ages. Our study implies that soil carbon loss should be taken into account during the implementation of ecological projects, such as reclamation and afforestation, in the arid and semi-arid regions of China.