Community Structure in Sympatric Rodents
Community Structure in Sympatric Rodents
复制标题
同域啮齿动物的群落结构
DOI：
--
复制
发表时间：
1976
期刊：
影响因子：
--
通讯作者：
R. M’Closkey
中科院分区：
文献类型：
--
作者：
R. M’Closkey
对7种共生啮齿动物的物种多样性、微生境分离、微生境迁移和体型进行了研究。通过对代表灌木结构和基质斑块的微生境变量的多组判别分析，识别出生境分离和季节转移。啮齿动物形成两个功能群。4种常年永久居留者(Pero-mnyscus eremicus、Neotoma Lepida、Neotoma fuscipes和Dipodomys Agilis)在栖息地结构上表现出明显的分离性，并出现了一些时间上的栖息地转移。三种季节性居民(Permyscus manulatus、Permyscus calforNicus和Reithrodontomys megalotis)没有表现出微生境的变化，并且彼此之间和与永久居民的微生境重叠的频率更高。对于任何给定的物种，生态位宽度与种群密度之间没有关系；然而，作为一个群体，季节性居民的生态位宽度随着种群密度的增加而减小。从季节性居民的生态机会主义角度讨论了这种模式的意义。根据栖息地结构，研究了动物体内体型差异的模式。栖息地结构的两两差异与个体大小呈正相关。数据显示，与至少有一个物种是季节性居民的配对相比，永久居民在身体大小和结构栖息地方面的差异更大。在身体大小和微生境结构上增加的相似性可能不利于某些物种对的全年共存。体型最相似的是同属鹿鼠(P.eremNicus和P.inanrulatus)，除了季节分离外，它们还在栖息地结构上表现出生态位差异。
Species diversity, microhabitat separation, microhabitat shifts and body size patterns are examined in seven sympatric rodent species. Habitat separation and seasonal shifts are identified by multiple-group discriminant analysis on microhabitat variables repre- senting shrub structure and substrate patchiness. The rodents form two functional groups. Four permanent, year-round residents (Pero- mnyscus eremicus, Neotoma lepida, Neotoma fuscipes, and Dipodomys agilis) show significant separation on habitat structure and some temporal habitat shifts. Three seasonal residents (Peromyscus maniculatus, Peromyscus californicus, and Reithrodontomys megalotis) show no microhabitat shifts and have a greater frequency of microhabitat overlap with one another and with permanent residents. There is no relationship between niche breadth and population density for any given species; however, as a group, seasonal residents show reduced breadth with increased popula- tion density. The significance of this pattern is discussed with respect to ecological opportunism of seasonal residents. The pattern of body size differences within the fauna is examined in light of habitat structure. Pairwise differences in habitat structure and body size are positively correlated. The data show that permanent residents are more different from one another in body size and structural habitat than pairs in which at least one species is a seasonal resident. Increased similarity in body size and microhabitat structure may not favor year-round coexistence in some pairs of species. The most similar-sized pair of species are congeneric deer mice (P. eremnicus and P. inaniculatus), and in addition to seasonal separation, they show niche dif- ference by habitat structure.