中文摘要：

水分是维持旱区生态系统健康与可持续性的关键因子.整地措施能够重塑地表微地形,利于旱区雨水收集、侵蚀防控和促进植被恢复,整地长期影响下的土壤水力学性质是本文的研究重点.以定西龙滩流域为研究区,通过野外采样与室内实验相结合,分析植被恢复过程中典型整地措施（鱼鳞坑、反坡台）的土壤水分时空分布、土壤水分特征曲线和水分常数,并辅以自然坡面为对照定量评价工程措施的土壤水力学特性.结果表明：（1）整地可以有效提高土壤水分含量.整地后土壤水分体积分数平均提高1.883%,相比自然坡面高出了22.62%.反坡台和鱼鳞坑整地后,土壤水分含量分别提高了29.69%和15.55%.（2）与对照相比,鱼鳞坑和反坡台的饱和含水量分别提高了7.52%和4.24%,有效水含量分别提高了4.74%和11.40%,整地措施能够提高土壤持水力和供水力,改善土壤水力学性质.（3）整地措施对表层土壤持水能力和供水能力的影响较深层大,与对照相比,鱼鳞坑和反坡台表层土壤（0~20 cm）有效水分提高了38.75%和23.84%,而深层（60~80 cm）有效水分与自然坡面差异只有3.34%和3.85%;土壤水分差异也随着土层深度而减少.本研究定量评价了不同整地方式和自然坡面的土壤水分特性,其结果期望为脆弱生态系统植被恢复和水土资源管理提供科学依据.

英文摘要：

Soil moisture plays a crucial role in maintaining the health and sustainability of dryland ecosystems. Terracing and other similar land preparations can reshape the natural slope and change underlying surface into different micro-landforms,which are significant for rainwater harvesting,erosion control,and vegetation promotion in arid regions. In this study,the Longtan Watershed in Dingxi region was selected as the study area. Based on in situ experiments,soil sampling analysis,and modeling simulation,the effects of land preparation and artificial vegetation（ Fish-scale pit/Adverse grade tableland-Platycladus orientalis） on soil moisture characteristics curves and soil moisture constants were quantitatively analyzed.（1）The land preparations could effectively improve the soil moisture content in the study catchment of Loess Plateau. Compared with natural slope,soil water content of land preparations increased by 1. 883%（ volume fraction） on average and fish-scale pit method and adverse grade tableland method enhanced the soil moisture by 29. 69% and 15. 55%,respectively.（2） Compared with the natural slope,fish-scale pit and adverse grade tableland could significantly improve the soil hydraulic properties. After carrying out the land preparations,saturated soil water content and soil properties such as field capacity increased by 4. 24%-11. 40%,suggesting that land preparations can improve soil moisture and water supply ability.（3） Surface soil moisture characteristics were better than those of the underlying soil layers after land preparations.Compared with the natural slope,fish-scale pit and adverse grade tableland＇s shallow soil layer（ 0-20 cm） increased the moisture by38. 75% and 23. 84%,respectively,whereas in the deep layer（ 60-80 cm） the increment of moisture were only 3. 34% and 3. 85%,respectively. This research provides scientific basis for vegetation restoration and land improvement in fragile semi-arid ecosystems.