青海果洛地区不同鼠洞密度下高寒草甸植物生物量分布特征  

Biomass Distribution Characteristics of Alpine Meadow under Different Burrowing Plateau Pika Density in Guoluo Region,Qinghai Province

作　　者：孙飞达[1] 龙瑞军[2] 蒋文兰[1] 路承香[3] 

机构地区：[1]甘肃农业大学草业学院,甘肃兰州730070 [2]兰州大学草地农业科技学院 [3]甘肃农业大学林学院,甘肃兰州730070

出　　处：《草地学报》2008年第5期475-479,共5页Acta Agrestia Sinica

基　　金：国家自然基金重点项目(30730069);国家自然基金面上项目(30600426)

摘　　要：为探讨不同密度下的鼠类活动对高寒草甸植物生物量的影响,本研究以高原鼠兔（Ochotona curzoniae）的有效鼠洞作为调查对象,分析了不同鼠洞密度对黄河源区青海果洛高寒草甸植物地上、地下和总生物量的影响。结果表明：随着草地鼠洞密度的增大,植物地上、地下和总生物量呈“V”字型变化趋势,先急剧下降后缓慢上升,满足y=ax2＋bx＋c关系;其中样地Ⅰ（3个/25 m×25 m）生物量最大,样地Ⅳ（54个/25 m×25 m）最小,样地Ⅴ（85个/25 m×25 m）鼠洞密度较大,而生物量并不是最小值;植物地下生物量主要分布在0-10 cm的范围内,随着鼠洞密度的增大有向表层聚集的趋势,生长旺盛期更为明显。植物群落组成中,随着鼠洞密度增大,莎草类和禾草类地上生物量均呈现下降趋势,而杂类草则趋于增加。The activity of plateau pika has either harmful or beneficial effects to the alpine meadow ecosystem and the transformation between both sides is determined by the population density of plateau pika. In order to study the effect of plateau pike activities under different population densities on the hiomass of alpine meadow, the effects of burrow densities were investigated on the aboveground, underground, and total biomass of alpine meadow in Guoluo Region, an important source region of Yangtze and Yellow rivers in Qinghai Province. The results show that, with the burrowing plateau pika density increasing, the aboveground, underground, and total biomass changed in a ‘V＇ trend, i.e. declined sharply at first and then rose slowly, which could be simulated by y = ax^2 ＋ bx ＋ c. The biomass of plot I （3 burrows in 25 m×25 m） was the largest and plot IV （54 burrows in 25 m×25 m） was least, and the plot V （8 burrows in 25m×25m） had highest burrow density but the biomass was not the minimum. The underground biomass was mainly distributed at soil depth of 0 to 10cm and prone to congregate in soil surface layer, especially during the active growing period. Regarding the dynamics of community components, the sedges and grasses decreased but the forbs increased consistent with the increasing of burrow density.

关 键 词：鼠洞密度 高寒草甸 植物生物量 分布特征 

分 类 号：Q145[生物学—生态学]