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对比研究了古尔班通古特沙漠与绿洲交错带8种土地利用类型的土壤特性变化.结果表明:不同土地利用类型的土壤粉砂含量差异性显著(P<0.05).人类活动干扰的时间越长、强度越大,粉砂和极细砂含量越高,而细砂反之.在人类活动干扰前期(≤5a),土壤养分与干扰时间成反比,而后(>5a)与时间成正比.不同土地利用类型的土壤养分分为4个等级:1级为盐碱地,为最高等级;2级为生态防护林地、荒草地和天然灌木林地;3级为10a农田地、5a菜园地和3a农田地;4级为5a农田地,为最低等级.人类活动使得土壤盐分由原来的(盐碱土)上层高、下层低转为上层低、下层高.而且盐分与干扰时间成反比.土地利用变化的过程中,土壤盐分与Cl-、SO24-、Ca2+、Mg2+、K+和Na+离子均成正比,而与HCO3-离子成反比.5a农田地土壤退化指数(-30.58%)最高,是其他土地利用类型的1.5～3.9倍.
The soil characteristics of eight land use types in the Gurbantunggut desert and oasis ecotone were compared and studied.The results showed that the content of soil silt in different land use types was significantly different (P <0.05), and the time of human disturbance The longer the intensity, the higher the content of silt and fine sand, whereas the fine sand, on the contrary, the nutrient content of soil is inversely proportional to the disturbance time (≤5a) and then to the time (> 5a). Soil nutrients of different types of land use are divided into four grades: the first grade is saline-alkali soil, the highest grade; the second grade is ecological protection forest land, grassland and natural shrub land; the third grade is 10a farmland, 5a vegetable garden and 3a farmland ; 4 is 5a farmland, the lowest level.Human activities make the soil salt from the upper (saline-alkali soil) upper high, the lower into the upper low, the lower high, and salinity and interference time is inversely proportional to the process of land-use change , Soil salinity is proportional to Cl-, SO24-, Ca2 +, Mg2 +, K + and Na + ions, but inversely proportional to HCO3- ions.The soil degradation index (-30.58%) in farmland5a is the highest and is the highest in other land-use types 1.5 to 3.9 times.