选取青藏高原典型多年冻土区风火山小流域高寒草甸和沼泽化草甸典型样地进行人工降雨截留试验,综合运用统计分析、模型回归分析等方法,对两种草甸类型截留特征及其影响因子进行分析.结果表明:两种草甸类型对降雨的截留能力是不同的,高寒草甸最大截留量0.61 mm,沼泽化草甸为0.18 mm;高寒草甸的最大截留率为12.4%,沼泽化草甸为3.8%.通过分析各因子对截留的影响,得出高寒草甸截留量与降雨量呈对数函数关系,沼泽化草甸截留量与降雨量呈二次多项式关系;两种草甸截留量与降雨强度都呈幂函数关系,与植被盖度均呈线性相关关系.

This study examines the interception characteristics during the artificial precipitation experiments over alpine and swamp meadows in a small-sized permafrost catchment Fenghuoshan located in the Qinghai-Tibet Plateau. The interception data under different rainfall intensity conditions were collected during the experiments. The data were analyzed using the statistical methods. The result shows that the canopy interception for alpine meadow can reach a high value of 0.61 mm, while only 0.18 mm is found for swamp meadow. The maximum rates of canopy interceptions for alpine and swamp are 12.4% and 3.8%, respectively. The relationship between the canopy interception and rainfall amount for alpine meadow can be represented by a power function; while a quadratic polynomial relationship is derived for swamp meadow. Such relationship becomes a power function for both meadows if rainfall amount is replaced by rainfall intensity. A linear relationship between the canopy interception and the density of vegetation coverage is also found for both meadows.