重庆四面山林地土壤水分特性

Soil water characteristics of forestlands in the Simian Mountains of Chongqing southwestern China

本文对重庆四面山林地土壤持水、蓄水和水分渗透特性进行了研究。结果表明:针阔混交林土壤具有较好的持水与蓄水功能,其土壤饱和持水量与非毛管持水量分别为274.43、66.05t/hm2;有效蓄水容量针阔混交天然次生林为107.82t/hm2,人工林为123.36t/hm2。阔叶林土壤渗透能力较强,其次为针阔混交林、针叶林。阔叶林土壤水分初渗速率与稳渗速率,天然次生林为46.500与3.257mm/min,人工林为37.917与2.088mm/min。Horton渗透模型对研究区内林地土壤水分入渗速率的拟合程度较好,r为0.959。天然次生林土壤持水性、蓄水性和渗透性优于人工林,应加强对人工林的管理,以提高其土壤水分性能。

Soil water holding and storage capacities,as well as infiltration properties of different forestlands were studied in the Simian Mountains of Chongqing,southwestern China.The results showed that soils in the mixed broadleaf-conifer forests had the highest water holding capacity and storage capacity,with a saturated water capacity of 274.43 t /hm2 and a non-capillary water capacity of 66.05 t /hm2.The effective water storage capacity of natural secondary mixed forests was 107.82 t /hm2,while that of the plantations was 123.36 t /hm2.The water infiltration capacity of broadleaved forests was larger than that of mixed forests and conifer forests.The initial and stable soil infiltration rates of natural secondary broadleaved forests were 46.500 and 3.257 mm /min,respectively,and of plantations 37.917 and 2.088 mm /min,respectively.Horton＇s infiltration model best fitted the data on the infiltration process of forest soils in this region （r = 0.959）.Therefore,the natural secondary forests were better than the plantations with regard to their soil water holding capacity,storage capacity and infiltration property.Plantation management should be strengthened to improve soil water properties.