古尔班通古特沙漠2种典型固沙措施的生态恢复效应

草方格和草方格-人工林综合防护措施是荒漠区风沙危害防治和生态恢复的重要措施，以古尔班通古特沙漠建植的草方格和草方格-人工林综合防护措施区为研究对象，相邻自然沙垄为对照，通过调查和计算植物多样性指数、丰富度和多度，测定土壤养分指标，对比分析了2种措施的生态恢复效应。结果表明:1）草方格和草方格-人工林综合防护措施实施后，植物多度由裸沙地分别恢复至22株和87株，物种丰富度分别达到了19和26，科数分别达到了9科和12科；草方格样地内土壤养分各指标值除有效P、全N、有机质低于自然沙垄外，全P、全K、有效N、速效K均基本恢复至自然沙垄水平，草方格-人工林样地内除全K含量与自然沙垄基本一致，其余指标均极显著高于（P＜0.01）自然沙垄。2）植物多度、丰富度、多样性指数均表现为草方格-人工林样地＞草方格样地，且前者群落生活型结构比后者更复杂，演替速度也更快。3）人工林建植产生的灌丛“肥岛”效应，使得草方格-人工林样地内土壤养分含量显著提升，土壤养分各指标的富集率除全K与草方格样地基本一致外，有效P、全N、有机质、全P、有效N、速效K均高于草方格样地。综上所述，在古尔班通古特沙漠工程扰动区，采取草方格-人工林综合防护措施比仅采用草方格措施更有利于生态恢复。

Ecological Restoration Effects of Two Typical Sand Fixation Measures in the Gurbantunggut Desert

The straw checkerboard barrier and vegetation protective system play important roles in desertification control and ecological restoration in desert area.In order to figure out the ecological restoration effects of straw checkerboard barrier and vegetation protective system,we investigated the diversity index,species richness,abundance and measured the indicator of soil nutrients.Our results showed that 1) the implementation of straw checkerboard barrier and vegetation protective system had significant effects on ecological indicators and soil nutrient indicators in the research area.The plant abundances of the two measures per square meter restored from bare sand to 22 and 87,respectively,and the species richness reached 19 and 26,respectively.The number of plant families reached 9 and 12,respectively.The available phosphorus,total nitrogen,and organic matter of soil nutrient indicators in straw checkerboard barrier plot were lower than those of natural dune,while the total phosphorus,total potassium,available nitrogen,and available potassium basically restored to the levels of natural dune.In the vegetation protective system plot,except that the total potassium was basically the same as the natural dune,the other indicators of nutrients were significantly higher (P＜0.01) than those of the natural dune.2) The plant abundance,richness and diversity index in the vegetation protective system plot were higher than the straw checkerboard barrier plots,and the community lifeform structure was more complex and the succession speed was also faster than the plants in straw checkerboard barrier plots.3) Due to the “fertile island” effect of the shrubs produced by the plantation,the soil nutrient content in the vegetation protective system plots significantly increased.Except for the total potassium,the enrichment rates of available phosphorus,total nitrogen,organic matter,total phosphorus,available nitrogen,and available potassium in the vegetation protective system plots were higher than those of the straw checkerboard barrier plots.To sum up,in the disturbance zone of project in Gurbantunggut Desert,adopting vegetation protective system measures was more conducive to ecological restoration than merely adopting straw checkerboard barrier measures.