云南省玉龙鼠疫疫源地小型兽类垂直空间与季节生态位分析

Analysis on Vertical Spatial and Seasonal Ecological Niche of Small Mammals in Yulong Plague Foci of Yunnan Province

2015年4至12月,以玉龙鼠疫疫源地的核心区域文笔山为样区,在2 400 m以上海拔区间划分4个垂直生态带,采用夹夜法进行四个季节的小型兽类调查。根据生态位宽度指数(Bi)和生态位重叠指数(C_(ih))对该地区小型兽类垂直空间与季节生态位特征进行分析。调查共布鼠夹8 028次,捕获小型兽类1 583只,包括4目6科12属23种,其中,优势种齐氏姬鼠(Apodemus chevrieri)、大绒鼠(Eothenomys miletus)和中华姬鼠(A.draco)的垂直空间、季节以及时空二维生态位宽度指数较大,在4个季节的4个垂直空间均有分布。黑腹绒鼠(E.melanogaster)的垂直空间生态位宽度指数最高,对垂直空间资源利用最优。稀有种社鼠(Niviventer confucianus)、褐家鼠(Rattus norvegicus)、侧纹岩松鼠(Sciurotamias forresti)、南小麝鼩(Crocidura horsfieldi)、臭鼩鼱(Suncus murinus)和黄腹鼬(Mustela sibirica)的垂直空间、季节以及时空二维生态位宽度指数均近似为0,在资源轴分布上具有单一性。在垂直空间和季节生态位重叠方面,C_(ih)>0.3的种对分别为147对和152对,分别占总种对的58.10%和60.08%,大部分为与优势种和常见种组成的种对。C_(ih)=0的种对分别为42对和37对,占比16.60%和14.62%,大部分为与稀有物种组成的种对。在季节方面,C_(ih)>0.6的种对有78对,占总种对的30.81%。巢鼠(Micromys minuts)和黄腹鼬、侧纹岩松鼠和臭鼩鼱、南小麝鼩和玉龙绒鼠(E.proditor)3对小型兽类的垂直空间C_(ih)=1。巢鼠和南小麝鼩、臭鼩鼱,滇绒鼠(E.eleusis)和中麝鼩(C.russula)、黄腹鼬,中麝鼩和黄腹鼬,南小麝鼩和臭鼩鼱,6对小型兽类季节C_(ih)=1。结果说明,玉龙县小型兽类优势种、常见种生态位宽度和生态位重叠指数均高于稀有种,但整体对空间的占有利用合理,各种群在群落中具有各自的生态位,保证了种群相对稳定。此调查可为当地鼠疫等自然疫源性疾病的宿主动物调查和研究提供基础数据。

From April to December in 2015, the Wenbi Mountain was taken as the sample area in the core area of Yulong plague foci. Four vertical gradient zones were divided from 2400 m above the altitude. The night-trap method was used to investigate the small mammals in four seasons, and the characteristics of vertical space and seasonal niche of small mammals in this area were analyzed. A total of 1 583 small mammals belonging to 23 species were captured. The vertical niche width index ranged from 0 to 0.952 8, and the seasonal niche index ranged from 0 to 0.993 1. After integration, the time(season) niche width index(Bin1) ranged from 0 to 1.705 8, and the time-space 2 D niche index(Bin2) ranged from 0 to 1.926 7. Among them, the dominant species, Apodemus chevrieri, A. draco and Eothenomys miletus had higher niche width indexes in vertical space, seasonal and time-space 2 D niches, also had higher utilization of time and space resources. The rare species were Micromys minuts, Rattus norvegicus, Sciurotamias forresti, Crocidura horsfieldi, Suncus murinus and Mustela sibirica. The niche width index of vertical space, season and time-space were approximately 0, and the distribution of the resource axis was relatively single. The overlap index(C_(ih)) of vertical space and seasonal is between 0 and 1. The significant species pairs of C_(ih) > 0.3 were 147 and 152, accounting for 58.10% and 60.08% of the total species pairs, respectively, most of them are species pairs composed of dominant species and common species. The niche overlap index of space-time(Pih) is between 0 and 1, there were 208 significant species pairs with Pih > 0.3, accounting for 82.21% of all species pairs. Studies have shown that the niche width index and niche overlap index of dominant and common species of small mammals in Yulong plague foci were higher than those of rare species. But the overall use of space and time resources is reasonable, each group has its own ecological niche in the community, which ensures the relative stability of the community. This survey can provide basic data for the investigation and study of host animals of local plague and other natural foci diseases.