黄土丘陵区长期种植柠条坡地土壤饱和导水率及其影响因素  

Soil saturated hydraulic conductivity and its influencing factors on the slope with long-term plantation of Caragana korshinskii in the loess hilly region

作　　者：田昕 赵勇钢[1] 刘啟霞 杨璐 刘小芳 TIAN Xin;ZHAO Yonggang;LIU Qixia;YANG Lu;LIU Xiaofang(School of Life Science,Shanxi Normal University,030031,Taiyuan,China)

机构地区：[1]山西师范大学生命科学学院,030031,太原

出　　处：《中国水土保持科学》2023年第4期20-27,共8页Science of Soil and Water Conservation

基　　金：国家自然科学基金“黄土丘陵区植物根系与土壤大孔隙对优先流的影响”(42007064);山西省研究生教育创新项目“根系对土壤入渗性能的影响机制”(2021Y500)。

摘　　要：在坡面进行人工灌木种植,是黄土丘陵区控制水土流失、恢复脆弱生态系统的重要举措,但其对土壤饱和导水率(K_(s))的影响仍不明确。以黄土丘陵区带状种植3个不同年限的柠条坡地和对照荒草地为研究对象,研究5个坡位0~100 cm土层K_(s)变化特征及其主要的土壤影响因子,并利用土壤传递函数进行模拟分析。坡地K_(s)变化范围为6.81~60.77 mm/h,柠条种植年限和坡位对其有显著影响(P<0.05)。随柠条种植年限的增加,0~40 cm土层的K_(s)先升后降,40~100 cm土层的K_(s)则持续增加。坡下K_(s)最高,坡顶和坡中次之,坡肩和坡上最低。选取的6个土壤传递函数模型模拟结果表明:除考虑土层深度的W sten模型拟合相对较好外,其他模型预测值均小于实测值。通径分析得到有机碳、饱和含水量和土壤密度等是影响坡面K_(s)的关键土壤因子,据此构建的土壤传递函数模型可以更准确地预测K_(s)变化。综上,坡地长期种植柠条总体可以提高K_(s),但这种改变受柠条种植年限和坡位的共同影响。[Background]The saturated hydraulic conductivity(K_(s))can characterize the strength of soil water conductivity,which is an important indicator of soil water conductivity and is closely related to eco-hydrology and soil erosion.Artificial shrub planting on slopes is an essential measure for controlling soil and water loss and restoring fragile ecosystems in the loess hilly areas,but the effect on K_(s) remains unclear.Soil transfer functions are constructed by integrating easily measurable or obtainable soil indices to estimate K_(s) accurately.[Methods]This study focused on the sloping land planted with Caragana korshinskii for 15,25,and 35 years and a control wasteland with wild grass in the loess hilly areas of Ningxia.Three random sample plots were set up along the horizontal slope surface,each with three replicates.The characteristics of K_(s) variation were investigated and its main soil influencing factors at five slope positions,including top-slope,shoulder-slope,up-slope,mid-slope and low-slope were studied,from 0 to 100 cm(0-40 cm with 10 cm intervals,40-100 cm with 20 cm intervals).Six common soil transfer functions,Cosby1,Cosby2,Weynants,Saxton,Wang,and W sten,were used to fit K_(s).[Results]The K_(s) range was 6.81-60.77 mm/h,and C.korshinskii planting duration and slope position had significant effects(P<0.05).With the increase of C.korshinskii planting years,K_(s) first increased(15 years of planting)and then decreased in the 0-40 cm soil layer,while K_(s) continuously increased in the 40-100 cm soil layer.The highest K_(s) was at the slope bottom,followed by the slope top and middle,and the lowest at the slope shoulder and upper slope.The simulated results of the six selected soil transfer function models indicated that,except for the W sten model considering soil layer depth,the predicted values of other models were all lower than the measured values.Correlation analysis showed that K_(s) was closely related to other physical and chemical properties except capillary porosity.The influence of soil

关 键 词：饱和导水率 坡位 种植年限 通径分析 土壤传递函数 

分 类 号：S152.7[农业科学—土壤学]