三江源区不同鼠洞密度下高寒草甸植物群落生物量和土壤容重特性研究

近年来由于自然和人为因素的双莺影响导致三江源高寒草甸存在不同程度的退化,同时鼠害频繁.本研究主要对高寒草甸在不同鼠害梯度下的生物量和土壤容重变化情况进行研究.结果显示,不同鼠洞密度与地上,地下及总生物量没有直接的线性关系.8月地上、地下及其总生物量基本高于6月,地下生物量均远远大于地上生物量;6月地下/地上生物量在11.81～27.64倍,8月地下/地上生物量为8.48～30.90倍;各样地0～10 cm根系占总根系的百分率较高,6月达78.21%～83.45%,8月达79.32%～91.54%,0～10 cm根系占有量8月6月,10～20cm基本持平,20～30 cm为8月<6月.容重与各土层为正线性关系,y=ax b(r=0.759 5～0.999 7);根土质量比与各土层关系为y=ax2 bx c.

Alpine meadow plant community biomass and soil bulk density characteristics in different burrowing rodent density plots in the "Three-River Headwaters" region

The three headwaters of rivers of the Tibet plateau are known as the China "watertower",but in recent years the meadows have been seriously degraded by both natural factors such as significant rodent damage and human activities.This paper focused on the plant community biomass and soil bulk density at rodent burrows in different density plots in June and August to assess the mechanisms of meadow destruction and the effect of rodent control.Burrow densities had no direct linear relationship with aboveground,belowground,or total plant biomass.The middle degraded meadow plot had the greatest rodent population.In August,the aboveground,belowground and total plant biomasses were more than in June,and the belowground biomass was greater than aboveground.In June,the ratio of belowground and aboveground biomass was 11.81-27.64,and in August was 8.48-30.90.All plots had the most belowground biomass percent in the first(0-10 cm) of the three soil layers(10-20,20-30 cm).In June,the first layer was 78.21%-83.45% and in August was 79.32%-91.54%.Comparing the percentages in August and June,in the first layer August>June,in the second layer they were equal,while in the third layer August0)(R2=1).