The restorations of burrow systems is one of the key indices of the restoration of plateau pika (Ochotona curzoniae) populations,changes of burrows distribution can reflect population dynamic.We measured the density of plateau pika,the density of burrows and those burrows relative positions in a 2.79 hm2 alpine meadow during 2014-2016 in Qilian county of Qinghai Province,in which six 50 m × 50 m plots with lethal and block control,six 30 m × 30 m plots with lethal control and three 50 m × 50 m plots as control group.The average nearest neighbor and mean crowding index was used to analyze the distribution pattern and clump areas of available burrows,abandoned burrows,fecal pits and sportive pits respectively,and descriptive and correlation analyses were conducted between parameters.The results show that during the restoration of plateau pika (Ⅰ) the distribution pattern of available burrows changed from random to dispersed,abandoned borrows changed from random to clustered,fecal pits and sportive pits displayed no obvious changing trends;the restoration of available and abandoned burrows toward its original distribution patterns before lethal control,but both of them restored inadequately.(Ⅱ) The average nearest neighbor index of available burrows was positively correlated with density,abandoned burrows were negatively correlated with density,fecal and sportive pits displayed no obvious correlation with density;and only fecal pits have a significant negative relationship with population density.(Ⅲ) The clump arca changing trend of available burrows is well consisitent with fecal pits and sportive pits,and in compensating situation with abandoned burrows;and the variability of burrows clump area is much less than their density.It declared that:(Ⅰ) Hysteresis exists in burrows distribution pattern and burrows density during the restoration of platean pika.(Ⅱ) The distribution pattern of available and abandoned burrows are mostly decided by their density.(Ⅲ) Plateau pikas have more urgent demand for burrow system area than burrrow numbers during restoration.%高原鼠兔洞穴系统的恢复是其种群恢复的关键指标之一,洞穴分布的变化可以反映种群的动态.本研究于2014-2016年在青海省祁连县对2.79 hm2高寒草甸内高原鼠兔种群密度、洞穴密度和洞穴的相对位置进行跟踪观测.其中包括6个50 m×50 m的灭鼠堵洞处理、6个30 m×30 m的灭鼠处理和3个50 m×50 m的对照处理.分别采用平均最近邻指数和平均拥挤度指数分析洞穴系统中有效洞、弃洞、粪坑和嬉戏坑的分布模式及洞系表现面积,并对各参数进行描述性和相关性分析.结果显示:高原鼠兔种群密度恢复过程中(1)有效洞的空间格局由随机向离散分布转变,弃洞由随机向聚集分布转变,粪坑和嬉戏坑无明显变化趋势;有效洞和弃洞分布格局的恢复都朝向灭鼠前状态,但恢复的都不充分;(2)有效洞最近邻指数与其自身密度正相关;弃洞最近邻指数与其自身密度负相关;粪坑、嬉戏坑最近邻指数与其自身密度无显著相关性;其中,仅粪坑的分布最近邻指数与高原鼠兔种群密度呈显著负相关;(3)有效洞与粪坑、嬉戏坑表现面积的变化情况较为一致,与弃洞呈互补态势;洞系表现面积的变异性远小于洞穴密度.结果说明:(1)高原鼠兔洞穴分布格局和洞穴密度的恢复具有滞后性;(2)有效洞、弃洞的分布格局主要受洞穴密度的影响;(3)高原鼠兔种群的恢复过程中对洞系面积的需求优先于洞口数量.
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