泰安棕壤土不同土地利用类型饱和导水率比较

为了分析土地利用类型对土壤饱和导水率的影响,利用单环入渗概化解法对泰安棕壤土草地、麦地、果树行间裸地3种土地利用类型饱和导水率进行研究.结果表明:草地、麦地、果树行间裸地的饱和导水率、入渗速率以及累计入渗量呈现依次降低的变化趋势.随着时间的增加,累计入渗量不断增加,试验时间120 min内,草地累计入渗量最大,数值为78.564 cm;麦地入渗量次之,数值为67.609 cm;果树行间裸地入渗量最小,数值为30.082 cm.利用实测累计入渗量与观测时间的拟合关系,得到3种土地利用类型累计入渗量的表达式,对累计入渗量进行估算,草地、麦地、果树行间裸地累计入渗量计算值与实测值相对误差分别在6,8,7 min后波动在5%以内,在15,52,56 min后波动在1%以内,同时推求了草地、麦地和果树行间裸地3种不同土地利用类型下的土壤饱和导水率K_s分别为0.073 1,0.032 9,0.015 8,以期为不同土地利用类型对原状土饱和导水率的影响研究提供参考.

Comparison of saturated hydraulic conductivity among different land use types of Taian brown loam

In order to analyze the influence of land use types on soil saturated hydraulic conductivity,the saturated hydraulic conductivity of Taian brown loam in grassland,wheat field and bare land of fruit trees was studied by single-ring infiltration and generalized solution method.The results show that the saturated hydraulic conductivity,infiltration rate and cumulative infiltration,which are measured separately in grassland,wheat field and bare land of fruit trees,decrease in turn.With the increase of time,the cumulative infiltration amount increases continuously.Within 120 min of test time,the cumulative infiltration amount of grassland is the largest,with a value of 78.564 cm.Wheat field infiltration comes second,with a value of 67.609 cm.The bare land infiltration between fruit trees is the minimum,with a value of 30.082 cm.Using the fitting relation between the measured cumulative infiltration and observation time,the expression of cumulative infiltration rate to estimate the cumulative infiltration,grass and wheat field,bare land of fruit trees cumulative infiltration calculated values and measured values relative errors in 6,8,7 minutes fluctuate within 5%,and in 15,52,56 minutes fluctuate within 1%,at the same time,the derived soil saturated hydraulic conductivity,Ks of the grassland,wheat field and bare land of fruit trees under the three different land use types is 0.0731,0.0329,0.0158,respectively,so as to provide reference for the study on the influence of different land use types on the saturated hydraulic conductivity of undisturbed soil.