储草期增加食物对布氏田鼠越冬存活率的影响北大核心CSCD

布氏田鼠(Lasiopodomys brandtii)是内蒙古典型草原区主要鼠种之一。该鼠种在秋季将食物储存在储草仓内,以此来度过植被贫瘠的冬季。为探究储草期增加食物对布氏田鼠越冬存活率的影响,2004年10月,于内蒙古阿巴嘎旗白音图噶苏木的布氏田鼠鼠害草场随机选取两块100 m×200 m的样地,分别设为增食样地和对照样地。增食样地内给每个布氏田鼠洞群补充食物,每天补充500 g小麦,连续补充2 d共计1000 g。对照样地内则不做任何处理。2004年10月,采用标志重捕法调查两块样地内布氏田鼠种群数量,调查显示,增食样地和对照样地内,布氏田鼠数量分别为310只和318只,以该结果作为计算其越冬存活率的基数。2005年5月,返回样地再次进行标志重捕,分别计算两样地布氏田鼠的越冬存活率。卡方检验显示,储草期增加食物能显著提高布氏田鼠越冬存活率。增食样地布氏田鼠越冬存活率为41.3%,显著高于对照样地布氏田鼠越冬存活率(24.2%,P<0.01)。增食样地雌性和雄性布氏田鼠越冬存活率分别为45.4%和37.3%,均显著高于对照样地雌性和雄性布氏田鼠越冬存活率(25.8%和22.6%,P<0.01)。但样地内雌性和雄性越冬存活率均无明显差异(P>0.05)。本研究结果表明,补充食物可大幅度提升布氏田鼠冬季存活率,增加布氏田鼠越冬存活基数,对来年种群增长起重要作用。

The Effect of Increasing Food during the Storage Period on the Winter Survival Rate of Brandt's Vole

Brandt"s vole (Lasiopodomys brandtii) is one of the main rodent species in the typical steppe area of Inner Mongolia. Brandt"s voles store food in burrows in the fall to survive the winter when the vegetation is poor. In order to explore the effect of food storage during the forage period on the overwintering survival rate of Brandt"s vole, from October 2004 to May 2005, we selected 2 sample plots (the sample plot area is 200 m * 100 m, 2 hectares) in the Brandt"s vole grassland in Baiyintuga, Abaga Banner, Inner Mongolia. Each plot is 2 hectares, for a total of 4 hectares. The mark-recapture method are used to estimate the number of Brandt"s voles. The individual marking method is: apodization method. In September and October 2004, a marked recapture was completed respectively, of which September was pre-catch. Pre-catch can preliminarily investigate the population density of Brandt"s vole in the experimental plot. The overwintering population in October was basically stable. The October recapture results were used as the basis for calculating the overwintering survival rate. The overwintering population includes 91 family groups and 628 Brandt"s voles. One of the two plots was treated to increase food, and the other plot was used as a blank control. In the additional food treatment plots, 1000g wheat was added to each burrow group as an additional supplementary food (500g per day for 2 consecutive days), after supplementing the food, guard and observe for 1 day to ensure that Brandt"s voles can store the food in the burrow smoothly; The blank control plot did not do any treatment. In May 2005, a mark re-capture was carried out in two plots, the number of surviving individuals was calculated, and the effect of adding high-quality food during the storage period on the survival rate of Brandt"s voles was analyzed. The analysis method adopts the Chi-square test, and the statistical results show that the increase of food during the storage period is very important for the overwintering survival rate of Brandt"s vole. The overwintering survival rate of Brandt"s vole in the feeding treatment group was 41.3%, which was significantly higher than the control group"s overwintering survival rate of 24.2% (P < 0.01,N = 628,X_² = 20.82) (Table 2). The overwintering survival rates of female and male Brandt"s voles in the feeding treatment group were 45.4% and 37.3% respectively, which were significantly higher than the 25.8% and 22.6% survival rates of female and male Brandt"s voles in the control group (P < 0.01,N = 311,X_² = 13.07) (P < 0.01,N = 316,X_² = 7.73) (Table 3 and 4). However, there was no significant difference in overwintering survival rates between females and males in each group (P > 0.05) (Table 5 and 6). The results of this study show that high-quality winter food can greatly raise the winter survival rate of Brandt"s voles, increase the survival base of Brandt"s voles, which play an important role in population growth in the coming year.