摘要
通过对青海湖北部沙柳河镇不同植被类型土壤入渗实验测定,研究了不同植被类型土壤入渗特征及土壤蓄水性。结果表明,青海湖农场四大队厚土层低草地、高草地、油菜地和沙柳河镇南薄土层低草地的初渗率均值分别为4.55、4.71、0.64和2.31 mm/min,稳定前平均入渗率均值分别为2.09 mm/min、3.29 mm/min、0.53 mm/min和1.95 mm/min,稳渗率均值分别为1.53 mm/min、2.31 mm/min、0.32 mm/min和1.74 mm/min。在同一实验区,不同植被类型的土壤入渗率为高草地>低草地>油菜地。同种植被厚土层的初渗率大于薄土层,而厚土层的稳定前平均入渗率和稳渗率小于薄土层。不同植被类型、不同土层厚度的土壤达到稳定入渗所需的时间存在一定的差异,厚土层低草地、高草地、油菜地和薄土层低草地的入渗率达到稳定状态用时的均值分别为125 min、87 min、40min、49 min。霍顿模型是研究本区入渗过程较好模型,考斯加科夫模型和通用经验模型在本区的适用性相对较差。由于青海湖北部土壤颗粒间的孔隙和土壤的孔隙度比陕西黄土高原区的大,使得青海湖北部土壤稳渗率比陕西黄土高原区的较高。该区土壤厚度小,土壤水库容量小,蓄水能力小,旱年易发生草原退化。
Through the determination of soil infiltration experiments on different vegetation types in southern Shali- uhe Town of Qinghai Lake area, the characteristics of the soil infiltration and the water maintenance in soil of differ- ent vegetation types were analyzed. The result showed that the mean values of initial infiltration rate of low grass- lands, high grasslands and rape fields of thick soil in the fourth thin soil in southern Shaliuhe town were separate 4. 55,4. 71,0. stability were 2. 09, 3.29, 0. 53 and 1.95 mm/min respectively. and 1.74 mm/min separately. of rape fields was lowest. The group of Qinghai Lake Farm and low grasslands of 64 and 2.31 mm/min. Average infiltration before The steady soil infiltration was 1.53,2.31,0. 32 In the same land, soil infiltration of high soil infiltration of low grasslands was inte grasslands was highest. The soil infiltration rmediate. The time at which soil infiltration comes to a steady state was different among different vegetation types and soil thickness. Horton formula was a bet- ter one for fitting the experimental data, and the applicability of Koctakob formula and general empirical formula was bad in the study area. Soil porosity and the porosity among soil particle of southern Qinghai Lake were bigger than Shaanxi Loess Plateau＇ s, which led to that steady soil infiltration of southern Qinghai Lake was higher that of Shaanxi Loess Plateau. The characteristics of small soil thickness, low capacity of soil reservoir and little storage capacity in the study area determined the fragile ecological environment and grassland degradation easily occurred in drought years.
出处
《山地学报》
CSCD
北大核心
2013年第6期693-700,共8页
Mountain Research
基金
国家科技支撑计划项目(2007BAC30B01)
中国科学院黄土与第四纪地质国家重点实验室项目(SKLLQG1214)~~
关键词
土壤入渗率
低草地
高草地
油菜地
青海湖北部
soil infiltration
low grassland
high grassland
rape field
north Qinghai Lake
