内蒙古达赉湖地区蒙原羚的春季生境选择

Spring habitat selection of Mongolian gazelle(Procapra gutturosa) around Dalai Lake,Inner-Mongolia

2006年5-6月和2007年5-6月,我们在内蒙古达赉湖地区开展了蒙原羚春季生境选择研究。我们设置样线20条,共记录到蒙原羚64群次、453只次和蒙原羚活动痕迹243处。我们选择了20个与蒙原羚生境选择相关的生境因子,运用信息理论方法和Logistic回归方程,建立了蒙原羚出现与否与各生境因子之间的预测模型。运用资源选择函数和资源选择指数,揭示蒙原羚对各生境因子的选择性。结果表明：家畜干扰是影响蒙原羚春季生境选择的首要因子（β=10.898）;坡位、水源距离、坡度、隐蔽条件、围栏距离和植被类型对蒙原羚春季生境选择有重要作用（β〉1.000）;道路距离、地上生物量、植被高度、植物种类数、植被盖度等因子对蒙原羚春季生境选择影响不显著（β〈1.000）。蒙原羚对牲畜距离〈2000m和〉4000m,中下坡位及平地,水源距离4000-8000m,坡度〈10°,隐蔽条件（可视距离）〈3000m,离围栏距离1000-2000m的针茅和杂草植被类型生境有一定偏好。因此,春季蒙原羚保护的关键是降低放牧强度,应在边境地区控制牲畜数量和人口迁入,在离边境线较远地区进行草场科学管理和制定合理的放牧制度。在植被生长状况较差和水源缺乏年份,应适当进行食物和水源人工补给。另外,进行草场封育,加强打草监管并建立合理的围栏管理制度,也是蒙原羚保护的重要环节。

The Mongolian gazelle （Procapra gutturosa） is the most abundant ungulate on the Asia-European steppe. During May and June of 2005 and 2006 we studied habitat selection of Mongolian gazelles on 20 randomly set transects around Dalai Lake, Inner Mongolia. We characterized 20 ecological factors that we hypothesized may determine habitat selection of Mongolian gazelles, with the aim of identifying key features influencing their habitat use. We used an information theoretic approach and logistic regression to build habitat selection models, and used a resource selection index and a resource selection function method to assess preference of primary habitat factors. The most parsimonious auto-logistic model was a good predictor of Mongolian gazelle habitat selection. Livestock disturbance was an important covariate predicting gazelle presence（β=10.898）.Position on slope, distance from water, slope, shelter, distance from fences,and vegetation type were important predictors of habitat use by Mongolian gazelles（β〉1.000）. Distance to nearest road,aboveground vegetation biomass,plant height,vegetation cover and species richness were secondary factors which lacked significant predictive value on habitat use（β〈1.000）. Gazelles preferred habitats 〈2 000 m and 〉4 000 m from livestock distance, lower and middle portions of slopes as well as flat areas, distance from water sources of 4 000-8 000 m, slopes of 〈10°, 〈3 000 m shelter condition （viewable range）, 1 000-2 000 m from fences, and vegetation types characterized by Stipa spp. and forbs.Habitat selection models and corresponding tables of important resources can be used to guide and evaluate future conservation activities of Mongolian gazelle. The principal strategy for its conservation in spring is to reduce intensity of grazing by domestic livestock. Controlling the livestock population in the trans-boundary area, and scientific grassland and grazing management in areas further from international borders are important for conservation of Mongolian gazelle. Furthermore, artificial supply of food and water, grassland protection, grass cutting rationalization and reasonable fence construction and management are effective policies for conservation of this species.