干旱区沙漠-绿洲过渡带固沙植物的土壤水分入渗特征

Soil moisture infiltration characteristics of different sand-fixing plants in the desert-oasis transition zone in arid region of China

为了探明干旱区不同固沙植物的土壤水分入渗特性,在黑河中游的甘肃省临泽县北部的沙漠-绿洲过渡带内选取3种固沙植物为研究对象,采用双环刀常水头试验法测定土壤水分入渗过程,并进行不同模型的模拟与分析。结果表明:(1)土壤水分入渗率与土壤初始含水率负相关,且在入渗初期相关性显著。(2)3种固沙植物的初始入渗率、稳定入渗率和平均入渗率均表现为梭梭(Haloxylon ammodendron)>沙拐枣(Calligonum mongolicum)>泡泡刺(Nitraria sphaerocarpa),且差异性显著(P<0.05)。(3)不同固沙植物的土壤水分入渗过程模拟显示,Philip模型最优,Horton模型次之,Kostiakov模型最差,Philip模型更适合研究该区域不同固沙植物的土壤水分入渗过程。研究可为干旱区土壤水分的合理利用及退化生态系统的植被恢复与重建提供科学依据。

In order to explore the soil moisture infiltration characteristics of different sand-fixing plants in arid areas,three sand-fixing plants were selected in the desert-oasis transition zone in the middle reaches of the Heihe River in the north of Linze County,Gansu Province. The soil moisture infiltration was measured by the doublering knife constant head test method,and carry out simulation and analysis of different models. The results show that:(1)The soil moisture infiltration rate has a negative correlation with the initial soil moisture content,and the correlation is significant at the initial stage of infiltration.(2)The initial infiltration rate,stable infiltration rate,and average infiltration rate of the three sand-fixing plants showed the order of Haloxylon ammodendron>Calligonum mongolicum>Nitraria sphaerocarpa,with significant differences(P<0.05).(3)The simulation of the soil moisture infiltration process of different sand-fixing plants shows that the Philip model is the best,the Horton model is second,and the Kostiakov model is the worst. The Philip model is more suitable for studying the soil moisture infiltration process of different sand-fixing plants in this area. Research can provide a scientific basis for the rational use of soil moisture in arid areas and the restoration and reconstruction of degraded ecosystems.