中文摘要：

动物常依据捕食风险强弱改变其行为策略,在警戒与采食及其它行为的时间分配上权衡,这一理论称为捕食风险的时间分配假说。该假说已在高原鼠兔等动物中得到验证,但对在中亚荒漠地区有代表性的啮齿动物大沙鼠（Rhombomys opimus）是否成立至今未被验证。通过行为观察,比较警戒与采食等行为在单位观察时间内总累积时间、单次行为持续时间以及活动频次之间的关系,验证大沙鼠行为规律是否符合捕食风险的行为时间分配假说。结果显示大沙鼠警戒行为的总累积时间与采食等其它行为间存在显著负相关（警戒与总地表活动：r=-0.727,P〈0.001;警戒与采食：r=-0.515,P〈0.001;警戒与储食：r=-0.174,P〈0.001;警戒与其它行为：r=-0.142,P=0.001）,警戒单次持续时间也与其它行为的单次持续时间存在显著负相关（警戒与地表活动：r=-0.157,P〈0.001;警戒与采食：r=-0.126,P=0.002;警戒与储食：r=-0.094,P=0.024）。此外大沙鼠警戒频次与其活跃程度紧密相关,大沙鼠活动频繁时,伴随的警戒次数也多（警戒与总地表活动：r=0.404,P〈0.001;警戒与采食：r=0.311,P〈0.001;警戒与储食：r=0.297,P〈0.001;警戒与其它行为：r=0.366,P〈0.001）。研究表明：大沙鼠在警戒与采食等其它行为的时间分配上存在明显权衡,支持捕食风险的时间分配假说,并且其警戒行为亦与活动频次有关,当大沙鼠活动频繁时,伴随的警戒行为次数也越多。

英文摘要：

The predation risk allocation hypothesis states that predation risk has an effect on animal’s behavior,and the animal will make trade-offs between vigilance and other behaviors such as foraging and storing according to the level of predation risk.When the risk is high,animal will reduce foraging and other behaviors,and allocate more time on vigilance,and vice versa.This hypothesis has been proved to be true for some animals such as Ochotona curzoniae,but for the wide distributed species in deserts of Central Asian Rhombomys opimus,this hypothesis has not been tested yet.This paper used the focal animal sampling method to get the behavior data of the R.opimus,and tested the predation risk allocation hypothesis.The research was conducted during the breeding season of the R.opimus from May to August in the year of 2010.The R.opimus ’s behavior was observed from 8：00 to 22：00 everyday.The behaviors of the R.opimus were classified into 4 kinds： vigilance,foraging,storing,and other activities.And the paper treated all 4 kinds of these activities as the total ground activities.Each behavior was recorded by total duration time,mean duration time of each time,and frequency of the activities for each 60 min observation sessions.The paper used Pearson Correlations to detect the relationships between vigilance and foraging,storing,total ground activities and other behaviors.The results indicated that vigilance has a significant negative relationship with foraging and other behaviors compared by total duration time in each 60 min observation samples（vigilance vs total ground activities：r=-0.727,P0.001;vigilance vs foraging：r=-0.515,P0.001;vigilance vs storing： r=-0.174,P0.001;vigilance vs other behaviors：r=-0.142,P=0.001）and mean duration of each times（vigilance vs total ground activities：r=-0.157,P0.001;vigilance vs foraging：r=-0.126,P=0.002;vigilance vs storing：r=-0.094,P=0.024）.When compared by activities frequency,vigilance showed a significant positive relationship with foraging and other