科尔沁沙地植被恢复及其对土壤的改良效应

Vegetation restoration and its effects on soil improvement in Horqin sandy land

探讨了对科尔沁沙地乌兰敖都地区流动沙丘采取生物和工程措施建立起人工固沙植被的相关配套技术，并就植被恢复程度对土壤改良效应进行了对比研究。结果表明：在流动沙丘进行人工固沙时采用1.0m×1.0m草方格内播种小叶锦鸡儿（Canagana microphylla）种子的措施具有较好的固沙效果，一般经过2年可使沙丘表面得到固定。在围栏封育条件下实施适宜的植被恢复措施，一般可在2-3年获得明显的固沙效果。小叶锦鸡儿人工固沙群落内土壤养分随着群落的生长发育而发生变化，在0-30cm土层中，有机质、速效钾、全氮、水解性氮、全磷、有效磷含量都表现为：11年生群落〉6年生群落〉流动沙丘；小叶锦鸡儿人工群落的建立可大幅度提高土壤微生物生物量，并随着年龄的增加，微生物生物量C、N、P的含量均呈现增加趋势。

Horqin sandy land, located in the transition zone of North-east plain and Inner Mongolian plateau, is the typical ecotone of fanning and grazing in northeastern China. In this region, arid climate and unreasonable human activities leads to severe desertification, which is an important ecological problem in east region of Inner Mongolia. Here, we discussed the biological and engineering technologies that fixed the mobile and semi-mobile sand dunes. The responses of soil improvement to vegetation restoration in Horqin sandy land were also analysed. The results showed that： （1） Planting seeds of Caragana microphylla in 1.0 m×1.0 m size straw checkboards could achieve the better sand-stablizing effect and the mobile sand dune could be fixed in 2 years. （2） The restoration effects of artificial sand-fixed community atter enclosure would be showed in 2 or 3 years. （3） The soil nutrients of artifical sand-fixed community increased with the development of Caragana microphylla community, the organic matter, available K, N, P and total N, P in soil depth （0-30 cm） showed the same tendency： fixed sand dune have been fixed for 11 years〉 fixed sand dune have been fixed for 6 years〉mobile sand dune; the building of artificial community could improve the soil microbe biomass, and the content of microbe C, N, P increased with the development ofcaragana microphylla shrubs.