摘要
通过对青海省铁卜加牧业气象试验站1987-1996年土壤含水率观测资料的分析,对天然草地土壤含水率随时间、土层深度的变化规律及各时段土壤含水率与降水的关系进行了初步研究。分析表明:春季解冻时土壤含水率主要取决于上年度封冻前的土壤水分贮存量和冻结与解冻过程中的平衡调节作用,据此可建立主要土壤层含水率预报方程;牧草返青期间土壤含水率平均状况既与当时的降水量有关,又与上年乃至前年的降水量存在显著的相关性,并建立了春季土壤含水率平均状况的长期预报模式;年度土壤含水率既与当年降水量有关,也与上年度降水量有较大关系,降水对土壤含水率存在时间和深度上的滞后效应;年度土壤含水率随土层深度呈现出明显的规律性,在40 70cm形成相对高湿土壤层;在环青海湖半湿润气候区,土壤水分不能充分满足牧草生长发育的需要。
Base on observed soil moisture data during 1987 and 1996 in Tiebujia animal husbandry meteorological experimental station, the relationship of soil moisture contents with the changes of seasons, soil depths and rainfall was analyzed. The forecast models of soil moisture content at different soil depths were established. The results showed that the soil moisture content during the spring defrost time mainly depended on the soil mois- ture storage before frozen in the last year and the balance of frozen and defrost process. The average soil moisture content during forage grass germination period was significantly related to the rainfall and to the rainfall in the last or before last year as well. It was same as by the annual soil moisture contents. The soil moisture content reached at a relative high level in 40 - 70 cm depths. The soil moisture did not meet the needs of the growth and development of the forage grass in the Qinghai Lake Region.
出处
《中国农业气象》
CSCD
2006年第2期151-155,共5页
Chinese Journal of Agrometeorology
关键词
土壤含水率
预报方程
降水量
环青海湖
天然草地
Soil moisture content
Forecast equation
Rainfall
Qinghai Lake Region
Natural grassland
