秦岭南坡森林有蹄类群落组成与垂直分布特征

The Community Structure and Evelvational Patterns of Forest Ungulates at the Southern Slope of the Qinling Mountains,China

野生动植物种群和生物多样性的垂直分布模式是生态学研究中的重要问题,而目前对于大型兽类的垂直分布模式却了解较少。本研究以秦岭南坡森林生态系统中的有蹄类动物为对象,使用相机陷阱调查技术（camera-trapping）,系统调查了研究区域内大中型兽类的分布情况。我们将研究区域按300m垂直间隔划分为5个海拔段,分别计算各海拔段内目标物种的相对多度指数（relative abundance index,RAI）和物种丰富度（species richness）,研究有蹄类动物群落的组成和垂直分布特征。2008年3~12月,共调查123个有效位点,在4 307个有效相机工作日中共记录到7种森林有蹄类动物。其中,羚牛（Budorcas taxicolor）为秦岭南坡有蹄类动物群落中的优势物种（平均RAI=110.66）,种群数量最多;其次是野猪（Sus scrofa）（RAI=28.25）和斑羚（Naemorhedus goral）（RAI=25.10）;林麝（Moschus berezovskii）则是群落中种群数量最少的物种（RAI=1.33）。在本研究所涉及的海拔梯度内,各物种种群数量的垂直分布模式为：羚牛和林麝为单峰型,种群数量在中间海拔段存在一个峰值,两侧递减;斑羚为单调递增型（R2=0.84）,种群数量大体随着海拔梯度的升高而增加;小麂（Muntiacus reevesi）（R2=0.94）和鬣羚（Capricornis sumatraensis）（R2=0.79）为单调递减型,种群数量随着海拔梯度的升高而减少;野猪和毛冠鹿（Elaphodus cephalophus）为复合型,分布模式较为复杂。整个有蹄类群落的物种丰富度的垂直分布表现为中峰模式,在1700~2300 m的中等海拔段最高,符合中域效应假说的预测。

The elevational patterns of wildlife population and community attract broad interests in ecologyresearch,wherever our knowledge on the patterns of large mammal fauna is poor. To determine the elevational pattern of ungulates in temperate mountainous forest of the southern slope of the Qinling Mountains,China,we conducted a camera-trapping survey on large terrestrial mammals in Changqing National Nature Reserve with systematic sampling. The reserve was divided into 500 m × 500 m grids and one passive infrared-triggered camera was set in each sampling block for a survey duration of 4- 6 weeks. We calculated the relative abundance index（ RAI） and species richness of detected forest ungulates at 300 m elevational intervals throughout the study area（ elevation range 1 400- 3 000 m）. We surveyed 123 camera locations from March to December,2008,and detected seven ungulate species with a sampling effort of 4 307 trap-days. Takin（ Budorcas taxicolor） was the most abundant ungulate species（ mean RAI = 110.66）,followed by wild boar（ Sus scrofa,RAI =28.25） and Chinese goral（ Naemorhedus goral,RAI =25.10）,whereas forest musk deer（ Moschus berezovskii） was the least（ RAI = 1.33）. We detected a unimodal elevational pattern in the populations of takin and forest musk deer,a liner pattern for Chinese goral（ R2= 0. 84）,Reeve＇ s muntjac（ Muntiacus reevesi,R2= 0. 94） and serow（ Capricornis sumatraensis,R2= 0. 79）,and a multiplex pattern for wild boar and tufted deer（ Elaphodus cephalophus）. The species richness of this ungulate community represented a unimodal pattern along an elevational gradient,with a mid-elevation peak at 1 700- 2 300 m,which consisted with the prediction of mid-domain effect hypothesis.