大兴安岭驯鹿(Rangifer tarandus)的春季生境选择

为确定分布于我国大兴安岭西北麓的濒危驯鹿(Rangifer tarandus)的春季生境选择特征,于2012和2013年的3—4月间,采用样线样方结合的生境调查方法,对内蒙根河驯鹿的春季偏好生境和对照生境进行了取样,并对样方的海拔和乔木郁闭度等23个生境变量进行了计测与分析。结果表明:与非利用样方(n=132)相比,驯鹿春季偏好生境(n=79)的海拔((957.27±1.68)m)、乔木郁闭度((32.84±2.72)%)、乔木密度(21.72±1.52)、地表植被盖度((85.06±1.03)%)、树桩数(6.81±0.45)和倒木数(5.73±0.54)均显著较大(Mann-Whitney U test,P0.05),而灌木盖度((57.95±2.79)%)、枯草盖度((33.11±2.79)%)、乔木高度((9.58±0.27)m)和灌木均高((59.85±2.69)cm)显著较小(Mann-Whitney U test,P0.05),而且驯鹿春季趋向于选择西坡和南坡(77.21%)的坡度较缓(93.67%)、位于坡中下位(67.09%)的生境,并偏好选择针叶林(68.35%)中的隐蔽度好(82.28%)、避风状况良好(64.56%)、湿润(60.76%)、距水源较近(≤1000 m,94.94%)及距人为干扰较远(≥1000m,87.34%)的生境(Chi-Square test,P0.05)。此外,驯鹿偏好生境的变量主成分分析结果表明,坡位、乔木特征(乔木胸径和乔木高度)、食物多度(灌木盖度、倒木数及树桩数)、雪被特征(雪深、雪盖度和郁闭度)、干扰强度(距人为干扰距离)、植被类型(坡向和植被类型)是影响驯鹿春季生境选择的重要因素,综合体现了驯鹿在春季对保温、食物和安全性的需求。

The spring habitat selection of reindeer (Rangifer tarandus) in Great Xing'anling of China

The reindeer (Rangifer tarandus) has been a wildlife resource used extensively by local people across its range for thousands of years. In China, the reindeer occurs only in the northeastern part of the Great Xing''anling area in Inner Mongolia. The Owenki people in this area have long exploited the reindeer for its hide, meat, velvet antlers, and milk, showing its economic importance. However, the reindeer has fallen into the critically endangered status, with only about 800 left in its native range. There have been some publications addressing biological and ecological characteristics of the Chinese reindeer, but most of them have been anthropological and ethnological studies of anecdotal character. To date, there has been no study on the habitat selection of reindeer. To implement an in situ conservation program for increasing its population, it is critical to study habitat selection of the reindeer in China. The purpose of this paper is to present quantitative survey results of the reindeer''s spring habitat selection in China and to explore the key factors influencing its habitat utilization. Thereby, implications for conservation measures to be implemented are discussed. In March and April of 2012 and 2013, habitat selection of the reindeer was surveyed in the Genhe area of northeastern China using line-transect surveys. A total of 23 habitat factors were measured and compared for 211 sample plots, in which 79 plots were designated as used-plots and 132 as non-used plots. The results indicated that reindeer in Genhe area preferred to select spring habitats at higher altitude ((957.27±1.68) m), with higher tree canopy ((32.84±2.72)%), tree density ((21.72±1.52) per 400 m²), increased ground-plant cover ((85.06±1.03)%), stump quantity (6.81±0.45), and fallen-wood quantity (5.73±0.54), but with lower shrub canopy ((57.95±2.79)%), withered-grass cover ((33.11±2.79)%), tree height ((9.58±0.27) m), and shrub height ((59.85±2.69) cm), compared to the non-used habitat plots. Moreover, the reindeer also selected habitats with intermediate to low slope (67.09%) on the south and west slopes (77.21%), which were located mainly in conifer forests (68.35%) and provided relatively good concealment (82.28%), more protection from wind (64.56%), relative proximity to water sources (< 1000 m, 94.94%), and were farther away from human disturbance (<1000 m, 87.34%). The principal component analysis showed that slope position, tree characteristics (tree height and tree diameter at breast height), food abundance (shrub cover, number of fallen wood, and stump number), snow characteristics (snow depth, snow cover, and tree canopy), disturbance intensity (distance from human influence), and vegetation type (slope aspect and vegetation type) were most important in determining the spring habitat selection of the reindeer. In summary, the results indicated that the reindeer''s habitat selection in the spring was a multidimensional process through which the reindeer could adapt to local ecological conditions of temperature, food abundance, shelter, water supply, and ground cover. Furthermore, the reindeer in China has not yet been domesticated, and it is necessary to introduce conservation methods for its protection since it is critically endangered species.