【摘要】 沙棘是黄土丘陵半干旱区的主要生态-经济型树种,在生态环境建设中有重要作用。利用野外长期观测资料,系统分析了该区人工沙棘林的水文作用。结果表明:7～10a沙棘林冠平均年截留率为8 5%,林冠截留率(I)与郁闭度(C)关系式为I=-1 59+0 018C1 439。5～10a沙棘林枯枝落叶层单次降雨可截留0 89mm降水。林地土壤入渗速率大于荒坡,其稳渗速率为1 5mm/min。林地土壤水分随季节变化明显,5月末0～500cm土层平均含水率为生长季最低,10月末最高。0～100cm土层是沙棘利用水分的主要层次,100cm土层是沙棘抵御持续干旱的主要层次。和荒坡比较,2～3a沙棘幼林减少产流的作用较小,产流量占荒坡的90 8%～99 5%,从4a起,产流量迅速减少,占荒坡的35 5%,10a沙棘林地的产流量为2 74t/hm2,仅占荒坡的5 3%。林地产流量(RS)与降雨量(P)和最大30min雨强(I30)密切相关,关系式为RS=0 094P0 603I300 610。更多还原

【Abstract】 Seabuckthorn is a main econo-ecological tree species of loess semi-arid region and has important effect on eco-environmental construction. On the basis of long-term measured data, hydrology of artificial seabuckthorn forest in the region has been analyzed. The results are as follows. Annual mean interceptive rate of seabuckthorn canopy in 7～10 ages is 8.5% and the relation between canopy interceptive rate （I） and closure （C） is I=-1.59+0.018C^1.439. Litter layers of 5～10 ages seabuckthorn forest can intercept 0.89mm rainfall in a single rain. Soil infiltrating rate of woodland is bigger than waste slope and its stable infiltrating rate is 1.5 mm/min. Soil moisture of woodland has an obvious change with season, mean soil moisture of 0～500 cm layer in end of May is the lowest of the whole growing season and the highest in October. The depth of 0～100 cm is the main layer of seabuckthorn using soil water and the depth of 100～500 cm is the main layer for seabuckthorn holding out against drought. Compared with waste slope, young seabuckthorn forest in 2～3 a has a little effect on runoff decrease and the runoff is 90.8%～99.5% of waste slope. Beginning from 4 a, seabuckthorn forest reduces runoff rapidly and the runoff accounts for only 35.5% of waste slope, runoff in 10 a seabuckthorn woodland is 2.74 t/hm² and account for only 5.3% of waste slope. Runoff （R_S） in woodland has a close correlation with rainfall （P） and 30 min maximum rain intensity (I₃₀) and the equation is R_S=0.094P^0.603I₃₀^0.610.更多还原