祁连山荒漠草原优势啮齿动物及其捕食者时空重叠度

Spatio temporal overlap of dominant rodents and their predators in desert steppe of Qilian Mountains

摘要:

【目的】 明晰啮齿动物及其捕食者时空分布特征，理解其种间关系。【方法】 于2020年12月至 2022年1月，在祁连山荒漠草原布设22台红外相机，以研究区主要优势啮齿动物大沙鼠（Rhombomys opimus）和子午沙鼠（Meriones meridianus）及其天敌兔狲（Otocolobus manul）和赤狐（Vulpes vulpes）为研究对象，基于获取的目标动物独立有效照片数据，分析4个物种活动节律及空间分布。【结果】 1）兔狲全年均有活动，月活动强度高峰期出现在5月和10月；赤狐冷季活动强度较高，暖季活动强度较低；子午沙鼠在3月和10月活动强度较高；大沙鼠活动时间主要集中在12月至次年5月。2）子午沙鼠和赤狐主要在夜间活动，大沙鼠和兔狲主要在昼间活动。3）兔狲与子午沙鼠活动节律重叠指数最高，其次为赤狐和子午沙鼠、兔狲和大沙鼠、赤狐和大沙鼠。4）兔狲和大沙鼠的空间重叠系数最高（0.92），其次为赤狐和大沙鼠（0.84）、兔狲和子午沙鼠（0.83）、赤狐和子午沙鼠（0.82）。【结论】 兔狲与子午沙鼠和大沙鼠的时空重叠度均高于赤狐。

Abstract:

【Objective】 Understanding the spatial and temporal distribution characteristics of rodents and their predators is essential for exploring the interspecific relationships.【Method】In this study，22 infrared cameras were set up in desert steppe of Qilian Mountains from December 2020 to January 2022 to capture independent and reliable photographic data of animals. The dominant rodents in the study area were Rhombomys opimus and Meriones meridi- anus，with their natural predators being Otocolobus manul and Vulpes vulpes. The activity patterns and spatial distributions of these four target species were analyzed based on their independent photographic data.【Result】 1） Otocolo- bus manual was active all year round，with peaks in activity intensity occurring in May and October. Vulpes vulpes showed higher activity in colder seasons and lower in warmer seasons. Meriones meridianus had higher activity intensity in March and October；while Rhombomys opimus was mainly active from December to May of the following year. 2）Meriones meridianus and Vulpes vulpes were primarily nocturnal，while Rhombomys opimus and Otocolobus manul were primarily diurnal. 3） The overlap in activity rhythm was highest between Otocolobus manul and the Mer- iones meridianus，followed by Vulpes vulpes and Meriones meridianus，Otocolobus manul and Rhombomys opimus， and Vulpes vulpes and Rhombomys opimus. 4） The spatial overlap coefficient was the highest between Otocolobus manul and Rhombomys opimus（0. 85），followed by Vulpes vulpes and Rhombomys opimus （0. 71），Otocolobus manul and Meriones meridianus （0. 69），andVulpes vulpes and Meriones meridianus （0. 68）.【Conclusion】 The spatiotemporal overlap between Otocolobus manul and Meriones meridianus，as well as Rhombomys opimus，was higher than that between Vulpes vulpes and Meriones meridianus or Rhombomys opimus.