Effect of different vegetations on soil organic matter and _biological properties in Muus sandland | 毛乌素沙地不同植被对土壤有机质和生物学特性的影响

Chinese. 研究不同植被对毛乌素沙地土壤有机质和生物学特性的影响，为沙区土地资源的可持续管理及当地脆弱生态环境的恢复重建提供科学依据。于2010-05在毛乌素沙地，选择海拔、坡向、坡度相近的30年踏郎、30年花棒、30年花棒×踏郎、40年樟子松、15年河北杨、20年杏树林地为研究对象，以流沙地为对照，对7块样地的土壤有机质含量、微生物数量和酶活性及三者之间的相关性进行分析，并通过最小显著差异法（LSD）评价样地之间有机质含量和生物学特性的差异显著性。在林龄相同的情况下，花棒×踏郎0～5 cm土层土壤有机质含量及生物学指标均高于纯林；河北杨0～5 cm土层土壤细菌数和蔗糖酶活性显著高于樟子松；杏树0～5 cm土层土壤有机质含量及微生物数量低于其他林地；与流沙相比，各样地土壤有机质含量和生物学特性各指标以0～5 cm土层增幅最为明显；土壤有机质含量和微生物数量与酶活性呈显著或极显著正相关。微生物数量及酶活性可作为判断土壤肥力的指标，酶活性可用来判断微生物数量的变化；沙区应营造多样性丰富的固氮混交林，减少纯林面积。

English. The research studied the effect of different vegetations on soil organic matter and biological properties in Muus sandland, and provide scientific proof for the sustainable management of land resources and reconstruction of vulnerable ecological environment in study area. In May 2010, compared with drift sand, the amounts of soil organic matter, microorganisms and enzymes activities of 30-year-old Artemisia sphaerocephala, Hedysarum scoparium and Artemisia sphaerocephala×Hedysarum scoparium, 40-year-old Pinus sytvestris var. mongolica, 15-year-old Populus hopeiensis and 20-year-old Armeniaca vulgaris with the similar elevation, aspect and slope were measured, and the relationship among them was studied. Least significant difference (LSD) method was used to analyze the differences of organic matter and biological properties among sample sites. The results showed that under the similar stand age, organic matter and biological indicators of 0-5 cm soil layers under H. scoparium×A. sphaerocephala were higher than those of A. sphaerocephala and H. scoparium. The number of bacteria and sucrase activity of 0-5 cm soil layers of P. hopeiensis were significantly higher than those of P. sytvestris var. mongolica. Soil organic matter content and microorganisms of 0-5 cm soil layers of A. vulgaris were lower than those in shrub lands. The amounts of organic matter and biological properties in drift sandland had the most remarkable increase in 0-5 cm soil layers. Organic matter content and microorganisms were significant or extremely significant to enzymes activities. Microorganisms and enzymes activities can be the indicators to judge soil fertility, and enzymes activities can be used to judge the growth of microbial. Mixed forests with nitrogen fixation should be planted in drought sand area and the area of pure forest should be reduced.