关键词: 温带草原, 氮添加, 磷添加, 地上生物量

Abstract: From May to November 2011, and by the method of focal animal sampling, this paper studied the burrow utilization (activity intensity on ground surface and frequency of entering burrow) by great gerbil (Rhombomys opimus) and its daily time budget of outside burrows in the southern part of Gurbantunggut Desert. The great gerbil spent 77.62%, 66.13% and 80.93% of their daytime outside burrows in spring, summer and autumn, and the frequency of their entering burrow in the seasons were 0.50, 0.31 and 0.19 times·min^-1, respectively. Both the activity intensity on ground surface and the frequency of entering burrow differed significantly over seasons. Feeding was the main behavior on ground surface, and the proportion of the time budget for feeding was greater than 50% during the three seasons. Storing food was another important behavior in spring and autumn, with the proportion of the time budget being 1719% and 2546%, respectively. In summer, grooming became most common after feeding, occupying 27.78% of the time budget. Our results demonstrated that food was the most important factor forcing the great gerbil to stay on ground surface for long time. Air temperature, physiological cycle, and predation risk also affected the ground surface activity, frequency of entering burrow, and daily time budget of the great gerbil.

Key words: temperate steppe, nitrogen addition, phosphorus addition, aboveground biomass.