摘要
[目的]揭示半干旱区固定沙丘不同坡位条件下土壤水分空间变化规律,为固定沙丘土壤水分合理利用提供决策依据。[方法]在毛乌素沙漠东南缘陕西省神木市生态协会毛乌素治沙造林基地,以固定沙丘12 a龄人工长柄扁桃林地为研究对象,建立土壤水分定位观测小区,使用CNC503DR型中子仪对2018年7—10月0—300 cm土层土壤水分进行测定,并分析不同坡位条件下长柄扁桃林地生长季土壤水分时空变化特征。[结果]①坡顶与坡上0—300 cm土壤剖面含水量随土层深度的增加呈先增加后减小,之后趋于稳定的变化趋势,而坡中(上、下)与坡底表现为类似S形的变化规律,土壤含水量表现为:坡底>坡中(上)>坡上≥坡顶>坡中(下);②坡底土壤含水量表现出强变异性,其他4种坡位条件下为中等变异;③不同坡位条件下蒸散发表现为:坡底>坡顶>坡中(下)>坡上>坡中(上),坡上属强变异,而坡底则表现出中等变异且变异系数最小。[结论]不同坡位条件对固定沙丘土壤水分及蒸散耗水具有重要影响,坡底土壤含水量及蒸散发量均最大,且具有较强的不稳定性。
[Objective]The spatial variation of soil moisture under different slope conditions in fixed sand dunes in semi-arid area was studied in order to provide decision-making basis for the optimal management of soil moisture in fixed sand dunes.[Methods]In the Mu Us sand land controlled and afforestation base of Shenmu ecological association of Shanxi Province in the southeastern edge of Mu Us sand land,the 12-year-old artificial Amygdalus pedunculate woodland in fixed dunes was taken as the research object.Soil moisture observation plots were established and CNC503DR neutron meter was used to measure soil moisture in 0—300 cm soil layer from July to October in 2018.The spatial and temporal variation characteristics of soil moisture during the growing season of Amygdalus pedunculate were analyzed under different slope conditions.[Results]①Soil moisture content of the 0—300 cm soil profile at the top and upper slope increased firstly and then decreased with the increase of soil depths,and then tended to be stable.However,the soil moisture variation of the middle(upper and lower)of the slope and the bottom of the slope showed a S-shape pattern.Soil water content and storage showed as:slope bottom>middle slope(upper)>the upper slope≥slope top>middle slope(lower).②The soil moisture content at the lower slope showed strong variability,while the other four slope conditions showed moderate variation.③Thevariation of evapotranspiration(ET)was as follows:bottom of slope>top of slope>middle of slope(lower)>upper of slope>middle of slope(upper).The variation of ET on slope bottom was medium and the coefficient of variation was the smallest.[Conclusion]Different slope conditions had important effects on fixed dune soil moisture and ET.Soil moisture content and ET at the bottom of slope was the highest and showed a strong instability.
作者
赵鑫
翟胜
李建豹
孙树臣
Zhao Xin;Zhai Sheng;Li Jianbao;Sun Shuchen(School of Environment and Planning,Liaocheng University,Liaocheng,Shandong 252059,Shandong,China;School of Public Administration,Nanjing University of Finance&Economics,Nanjing,Jiangsu 210023,China)
出处
《水土保持通报》
CSCD
北大核心
2020年第4期45-52,共8页
Bulletin of Soil and Water Conservation
基金
国家自然科学基金项目“沙漠长柄扁桃林地水量平衡的试验研究”(41701243)
“基于15N示踪的包膜尿素对棉田土壤氨挥发的影响研究”(41807092)
聊城大学博士科研启动资助项目(318051748)
聊城大学大学生科技文化创新项目(cxcy2019y061)。
关键词
坡位条件
土壤水分
空间变异
毛乌素沙地
slope conditions
soil moisture
spatial variation
Mu Us sandy land
