毛乌素沙地典型人工固沙林对土壤有机碳的影响

Effect of Typical Artificial Sand-fixation Forest on Soil Organic Carbon in Mu Us Sandy Area

通过对毛乌素沙地5种典型人工固沙林土壤有机碳含量/密度及垂直分布的差异性研究,揭示了不同类型人工固沙林对土壤有机碳的影响。结果表明:不同类型人工林0～100 cm土层有机碳平均含量排序为白榆群落>新疆杨群落>花棒群落>柠条锦鸡儿群落>沙柳群落>裸沙地,且均以0～20 cm土层含量最高,同时,柠条锦鸡儿群落、白榆群落和新疆杨群落土壤有机碳含量的垂直变化均表现为先下降后上升的趋势,与裸沙地相同,而沙柳群落和花棒群落趋势不明显,各植被类型土壤有机碳最低值出现的土层不同;不同类型人工林0～100 cm的土壤有机碳密度为白榆群落>新疆杨群落>柠条锦鸡儿群落>花棒群落>沙柳群落>裸沙地,以乔木林白榆群落和新疆杨群落土壤有机碳密度高于试验所选各灌木林,但柠条锦鸡儿群落土壤有机碳密度的最高值出现在80～100 cm土层,而其他植被类型土壤有机碳密度最高值均出现在0～20 cm土层。

Based on a study of the variance of the content/density and vertical distribution of soil organic carbon of 5 different typical artificial sand-fixation forests in Mu Us sandy area,the effect of different types of artificial sand-fixation forests on soil organic carbon were explored.The result showed that the sequence of the average content of organic carbon of 0 ~ 100 cm soil layer of different types of artificial forests was that Ulmus pumila communityPopulus alba communityHedysarum scoparium communityCaragana kroshinskii communitySalix psammophila communitybare sandy land and commonly the content of 0~20 cm soil layer was highest The vertical distribution of soil organic carbon of Caragana kroshinskii community,Ulmus pumila community and Populus alba community all showed a trend of decreasing first and then increasing and it was the same with the bare sandy land.The trend of Hedysarum scoparium community and Salix psammophila community were not obvious.The soil layers in which the minimum value of soil organic carbon appeared for various vegetation types were different.The sequence of the density of soil organic carbon of 0-100 cm soil layer of different types of artificial forests was that Ulmus pumila communityPopulus alba communityCaragana kroshinskii communityHedysarum scoparium communitySalix psammophila communitybare sandy land.The densities of soil organic carbon of the arboreal forest Ulmus pumila community and Populus alba community were higher than that of various shrub forest selected for the test.The maximum value of the density of soil organic carbon of Caragana kroshinskii community appeared in 80-100 cm soil layer and the maximum value of the density of soil organic carbon of other vegetation types appeared in 0~20cm soil layer.