重庆市四面山几种人工林地土壤水分特性研究  

Soil Water Characteristics of Different Plantations in Simian Mountain of Chongqing City

作　　者：王冉[1] 张洪江[1] 王伟[1] 杜士才 程金花[1] 吴煜禾[1] 

机构地区：[1]北京林业大学水土保持学院,北京100083 [2]重庆市林业局,重庆401147

出　　处：《水土保持通报》2011年第2期88-94,共7页Bulletin of Soil and Water Conservation

基　　金：国家自然科学基金项目(4077104230900866);"十一五"国家科技支撑计划重点项目(2006BAD03A1304)

摘　　要：采用压力膜仪法测定了重庆市四面山5种人工林地(杉木人工纯林,杉木×马尾松人工混交林,木荷×香樟×思栎×枫香人工混交林,木荷×思栎人工混交林,杉木×马尾松×木荷人工混交林)的土壤水分特征曲线,并据此对这5种人工林地的土壤水分特性进行了分析。结果表明,采用Gardner于1970提出的经验方程θ=aS-b能够较好地模拟这5种人工林的土壤水分含量与土壤水吸力间的关系,且拟合后的决定系数均达到0.99;通过对拟合参数a值的比较得出,5种人工林地的持水能力的顺序为:木荷×杉木×马尾松人工林(a=0.328)>木荷×香樟×思栎×枫香人工林(a=0.248)>杉木人工林(a=0.225)>木荷×思栎人工林(a=0.218)>杉木×马尾松人工林(a=0.206);通过拟合方程计算得出5种人工林土壤有效水上限吸力值为0.03MPa比较合适,而根据比水容量的计算显示,吸力值为0.15MPa时,植物所能吸收到的土壤水量显著减少,故把此吸力值作为易有效水与难有效水的界限;通过比较ab值(即拟合参数a与b的乘积,土壤水吸力S=1.00×105 Pa时的比水容量)和易有效水含量两个指标得出,5种林地不同土层的供水性能变化规律性不明显,但5种人工林地整体的供水性能顺序为:木荷×香樟×思栎×枫香人工林(ab=0.065,易有效水11.704)>杉木人工林(ab=0.062,易有效水10.677)>木荷×思栎人工林(ab=0.058,易有效水10.485)>木荷×杉木×马尾松人工林(ab=0.058,易有效水10.003)>杉木×马尾松人工林(ab=0.056,易有效水9.980)。Soil water characteristic curves were determined using a pressure-membrane extraction apparatus for the soils collected on five different plantations,i.e.,pure fir forest（Cunninghamia lanceolata）,fir and pine（Pinus massoniana） mixed forest,and three other mixed broad-leaved forest（Schima superba×Cinnamomum camphora×Lithocarpus glaber×Liquidambar formsana,Schima superba×Lithocarpus glaber and Cunninghamia lanceolata×Pinus massoniana×Schima superb） in Simian Mountain of Chongqing City.The results show that the empirical equation（θ=aS-b） proposed Gardner（1970） described well the relationship between soil moisture contents and soil water suctions for all the soils from the five forests with coefficients of determination greater than 0.99.In terms of the fitting parameter a values,the soil water retention capability of the five forest soils as in order from high to low were Cunninghamia lanceolata×Pinus massoniana×Schima superba（a=0.328）,Schima superba×Cinnamomum camphora×Lithocarpus glaber×Liquidambar formsana（a=0.248）,Cunninghamia lanceolata（a=0.225）,Schima superba×Lithocarpus glaber（a=0.218）,and Cunninghamia lanceolata×Pinus massoniana（a=0.206）,respectively.According to the regression equations,the soil water suction upper limit of soil available water was approximately 0.03 MPa.The specific water capacity indicated that soil available water decreased substantially when the suction is greater than 0.15 MPa,which implies that 0.15 MPa might be the critical value for differentiation of readily available water and slowly available water.According to the a×b values（the product of fitting parameter a and b,which equals to the specific water capacity when the soil suction S=1.00×105 Pa） and readily available water contents,although no obvious trend has been identified in the variations of soil water supply capability for different soil layers of five plantations,the soil water supply capability of five plantations in order from high to low were as followed： Sc

关 键 词：四面山 土壤水分特征曲线 持水能力 供水能力 

分 类 号：S152.7[农业科学—土壤学]