中文摘要：

在极端干旱区的策勒县绿洲荒漠过渡带,选择植被曾被砍伐殆尽的沙丘不同部位,对其微气候、土壤、植物、微生物、水分等进行观测分析。研究表明：微域地形对改变环境生态因子分布所导致的生态效果十分明显。沙丘间的微生境的差异巨大。在高度仅3～8m的沙丘上部和下部,微生物的数量和土壤含水量可相差1～2个数量级;而中午时段地面温度、气温、空气湿度的差值分别是10℃、6℃左右和10～20%。沙丘下部易于积水,温度较低,地表最高温度小于25℃;空气相对湿度大,5cm处变化在30-33%,50cm在19-22%之间;20-40cm的土壤含水量达10.5%,可基本满足植物生长的需要。因此,在沙丘间的凹地,水-热配置较适宜,植物着床和恢复最快,盖度大,微生物数量最多。沙丘的上部环境条件较差,植被恢复慢。中部介于两者之间。植被恢复过程能否顺利进行,早期受物理环境支配明显强于群落的生物环境因素。当植被盖度增加到一定程度后,植物反作用于生境,加剧了不同部位局地微生境的差异性。

英文摘要：

In extreme arid region oasis-desert ecotone of Qira,we chose different parts of sand dune to observe and analyze the microclimate,soil,vegetation,microorganisms and soil moisture.The results showed that the micro-terrain could obviously change the ecology effect by varying environment and the distribution of ecological factors.There were big differences of micro-habitats among dunes.Microorganisms number and soil moisture content between top and bottom of the 3 to 8 meters high dune could have 1 to 2 quantity difference level.In the midnoon,differences of ground temperature,air temperature and humidity were separately 10℃,6℃ and 10% to 20%.The bottom dune was more likely to assemble water,and had low temperature.The highest groud temperature was less than 25℃.But its air humidity was high.The humidity at 5cm hight was 30% to 33%,and 19% to 22% at 50cm hight.The soil moisture in 20cm ～ 40cm layer was 10.5%,which could basicly satisfy plants growth.Therefore,the distribution of water and heat was suitable in low dune place.Plants in this place had the quikest plantation recovery speed,large coverage and maximum microorganisms.The top dune had bad environment,so the plantation speed was slow.The condition of middle part dune was between the two dune parts above.In early stage,nature environment was more powerful than community organism factors in vegetation recovery process.When plants coverage increased,plants acted back on habitat,and then intensified the micro-habitats differences among different dune parts.