阿尔泰山南部科克森山和卡拉麦里山盘羊冬季卧息地的选择

Winter bed-site selection by argali Ovis ammon sairensis,O. a. darwini in Mt. Kekesen and Mt. Kalamaili in southern Altai Mountains

2007年11月至2008年1月,在阿尔泰山南部科克森山和卡拉麦里山采用样线法研究了盘羊冬季卧息地的选择性。结果表明,两地区的盘羊对冬季卧息地的利用均有选择性,两地区盘羊偏好利用山坡做卧息地,避免选择山沟和平滩卧息;偏好位于半阴和半阳坡的卧息地,避免利用阴坡,对阳坡随机利用;偏好位于上坡位和中坡位的卧息地,对下坡位则为随机利用。通过与对照样方比较,科克森山和卡拉麦里山盘羊冬季卧息地均以植物科数多、植物种数多、植物密度高、灌木株数小、驼绒藜株数少、接近隐蔽物、隐蔽级高和雪覆盖浅为主要特征。在科克森山,盘羊通常选择坡度大、雪覆盖浅的位置作为其卧息地。在卡拉麦里山盘羊通常选择坡度大的地方作为其卧息地。科克森山和卡拉麦里山盘羊卧息地变量前6个特征值的累积贡献率分别达到了80.75%和82.58%,较好地反映了盘羊卧息地的生境特征。科克森山和卡拉麦里山盘羊卧息地第1主成分贡献率分别达到了23.04%和24.33%。在两地区,植物科数、植物种数、灌木种数、雪深和坡度5个因子的载荷系数均为正值,具有较大的作用。其余5个主成分中隐蔽级、海拔、距水源距离和距居民点距离也很重要。

Winter bedding sites used by argali Ovis ammon sairensis, O. a. darwini were studied by using line-transect methods on Mr. Kekesen and Mt. Kalamaili, in the southern desert of Ahai Mountains, Xinjiang Ugyur Autonomous Region, China from November of 2007 to January of 2008. One hundred bedding sites used by argali and 100 control plots were located and measured during a 30 transect surveys crossing the entire study area on Mt. Kekesen, while 125 sites used by argali and 125 control plots were located and measured during 45 transects surveys crossing the entire study area on Mt. Kalamaili. Argali at both sites preferred slopes as bed sites, and avoided sleeping in valleys and on plains; argali showed a preference for slopes which were half exposed to the sun and avoided shady slopes ; argali showed a preference for the upper slope and the middle slope. Comparing bedding sites with control plots on the two mountains bedding sites of argali were characterized by steep slope angle, shallow snow cover, high plant density, low bush number, low Stipa sp. density, few Ceratoides arborescens near hiding spots, and high hiding cover. Results of Principal Component Analysis （PCA ） showed that the first 6 principal components explained 80. 09% and 82. 58% of the total variance among all bedding site variables on Mt. Kekesen and Mt. Kalamaili. PCA indicated that snow depth, slope angle, number of plant families, number of plant species, and number of bush species were important factors affecting bed-~ite selection by argali. PCA also indicated that hiding cover, altitude , distance to water resources and distance to human settlements were important factors affecting bed-site selection by argali.