天山中部不同林龄天然云杉林地表土壤入渗性能研究

Surface soil permeability characteristics in different ages of Picea schrenkiana var.tianschanica forests in the middle Tianshan mountains

通过对天山中部不同林龄天山云杉(Picea schrenkiana var.tianschanica(Rupr.)Chen et Fu)地表土壤和林外草地土壤进行实验室人工降雨模拟渗透试验,初步探讨了天山云杉林地土壤的入渗性能。结果表明:1)累积渗透量、入渗速率与入渗时间均呈幂指数相关关系。稳渗速率最高为近熟林1.9108mm/min,最低为林外0.31847mm/min。在充分的降雨条件下,不同林龄的入渗性能大小顺序为:近熟林>成熟林>中龄林>林外;幼龄林介于中龄林和近熟林之间。2)土壤入渗性能影响的首要因子是降雨强度,二者呈极显著正相关关系;累积入渗量与土壤初始含水量呈显著正相关;稳渗速率的主导因子,依次是土壤容重>非毛管孔隙度>总孔隙度>初始含水量>枯落物层厚度;初渗速率与枯落物层厚度、土壤容重、总孔隙度分别呈极显著正、负、正相关关系。3)建立了天山中部天然云杉林地表土壤入渗性能特征与各项主导因子之间的多元线性回归模型。4)研究表明,使用霍顿入渗模型,对天山云杉林地土壤的入渗性能能进行很好的模拟,相关性系数R2达到0.881以上。

Based on laboratory artificial rainfall and infiltration test on surface soil of central Tianshan Picea schrenkiana var.tianschanica forests in different forest age and grassland outside the forest,water infiltration ability of Picea schrenkiana var.tianschanica forests soil was assessed.The results showed：（1） Amount of cumulative infiltration,infiltration rate and infiltration time have power and exponential correlations.The highest steady-state permeability rate is 1.9108 mm/min;the lowest is 0.31847 mm/min in the soil of the P.schrenkiana var.tianschanica forests.Under sufficient rainfall condition,the sequence of soil infiltration capabilities in different age forests is： near-mature forest〉mature forest〉middle-age forest〉lawn.（2） The rainfall intensity is the primary influence factor for the soil permeability characteristics,and the extremely significant positive relation is stated between rainfall intensity and soil permeability capabilities.The relationship between soil cumulative infiltration and the soil initial water content is extremely significant positive;the leading factors of the steady-state permeability rates sequence is： bulk density〉un-capillary porosity〉total porosity〉initial water content〉the thickness of litter layer.The relationship sequence of the initial water content and the thickness of litter layer,bulk density and total pore degree one by one is positive significant,negative significant,positive significant.（3） A series of multi-element line models about the soil permeability characteristics and the influence factors of the surface soil in P.schrenkiana var.tianschanica forests were established.（4） Horton permeability model can well simulate the permeability characteristic of the soil in P.schrenkiana var.tianschanica forests,its correlation coefficient R2 is more than 0.881.