青海大通山地退耕还林土壤渗透性研究

土壤渗吸性能是土壤重要的物理特征之一,是生态效益的重要组成部分。采用双环渗透仪法,对国家退耕还林还草工程科技试验县———青海省大通县退耕地土壤渗吸性能进行了系统研究。结果表明:退耕土壤的总孔隙度、土壤容重、土壤含水量等物理性状与土壤的稳渗速率随着退耕年限的延长基本呈增大的趋势;土壤渗吸过程具有明显的幂函数关系,突出表现为初渗速度极大,而随着渗透时间的进行,其逐渐减小直至趋于某一常数亦即稳渗速度的过程;不同退耕年限土壤的渗透性能存在差异,同样渗水量退耕还林土壤最大渗透速率是农耕地的11.37倍,渗透深度为10.59倍。退耕还林后土壤的渗透性能得到了改善,提高了土壤的保水性能。

Study on Soil Permeability of Converting Cropland to Forest Region in Datong County of Qinghai Province

Soil permeability is one of the important physical properties of soil and important component of the ecological benefits.With the help of double-ring infiltrometer,soil permeability in Datong county,Qinghai Province is dealt with.The results show that just as the following.As time lasts,the total porosity of soil,bulk density of soil,moisture content and soil final infiltration rate of CCFG have crescent trend;The process of soil permeability has obvious power function connection.Its first infiltration rate is remarkably quick.Then as time goes by,it reduces gradually until reaches the final infiltration rate.There are obvious permeability differences in different age of converting cropland to forest,the most infiltration rate of soil of CCFG is 11.37 times of cropland,the infiltration deepness is 10.59 times of cropland in the same quantity of infiltration water.It shows the function of converting croplands to forest in improving permeability and water binding capacity of soil.