喀斯特地区植被恢复过程中土壤渗透性能及其影响因素

采用空间代替时间的方法,选取喀斯特地区大湾小流域不同植被恢复阶段样地和不同经果幼林样地,以烤烟坡耕地和柳杉人工林作为对照,研究喀斯特地区植被恢复过程中的土壤渗透性能及其影响因素。结果表明:1)土壤渗透性能由高到低的顺序为李树+金银花>刺梨+猕猴桃>李树+刺梨>枣树+玉米,乔木疏林>灌木林>灌草>乔灌过渡林>草坡>柳杉人工林;2)烤烟坡耕地土壤平均入渗速率与稳定入渗速率均次于乔木疏林地,烤烟坡耕地土壤入渗性能较好;3)考斯恰柯夫方程是比较适宜于描述喀斯特地区植被恢复阶段土壤入渗特征的模型;Philip模型和Horton模型对经果幼林的土壤渗透性能模拟效果较好,Horton模型的初始入渗速率和稳定入渗速率与实测值较为接近,适宜于描述喀斯特地区的土壤入渗过程;4)土壤的渗透性能与>0.05 mm砂粒质量含量呈显著正相关关系(P<0.05),与0.05～0.001 mm粉粒质量含量呈极显著负相关关系(P<0.01);土壤渗透性能的影响因素主要是土壤>0.05 mm砂粒质量含量和0.05～0.001 mm粉粒质量含量。

Infiltration characteristics of soil and its affecting factors in the process of vegetation recovery in Karst region

Effect mechanism of vegetation recovery on soil infiltration capability could provide scientific bases for soil and water conservation in Karst region.Compared with Nicotiana tabacum farmland and Cryptomeria fortunei plantation,this study selected different vegetation restoration stages and different young economic fruit forests as subject.Interchangeable space-time method were employed to study soil infiltration characteristic and its affecting factors.The results showed that：1） soil infiltration capability was given as the sequence of Prunus salicina intercropped with Lonicera japonicaRosa kweichowensis intercropped with Actinidia deliciosaPrunus salicina intercropped with Rosa kweichowensis Ziziphus montana intercropped with Zea mays,and thin arbor forestshrubshrub and grassarbor and shrubgrasslandplantation forest.2） The Nicotiana tabacum farmland had better soil infiltration capability as a result of its mean infiltration and steady infiltration rate were only lower than thin arbor forest.3） Infiltration process was performed well by Kostialov model for different vegetation restoration stages in this region.However,to young fruit forests soil,Philip or Horton models could give better performance.Initial soil infiltration rate and steady infiltration rate simulated by Horton model were similar to the measured values.So Horton infiltration model was the best model to describe soil infiltration process in the study region.4） There were significant positive correlation between sand concentration（1-0.05 mm in diameter） and soil infiltration（P0.05）.Soil infiltration were obviously negatively related to silt concentration（0.05-0.001 mm in diameter）（P0.01）.Sand concentration（1-0.05 mm in diameter）and silt concentration（0.05-0.001 mm in diameter） were main affecting factors to soil infiltration.