陕西黄龙山自然保护区褐马鸡育雏期取食地选择

Brood Habitat Selection of Brown Eared-Pheasant (Crossoptilon mantchuricum) in Huanglongshan Nature Reserve,Shaanxi,China

2006年5-6月,在陕西黄龙山林区采用样线样法对褐马鸡(Crossoptilon mantchuricum)育雏期取食地的选择进行了研究.共设74个样方,其中利用样方20个,共遇见20个不同的家族群,平均大小为(10.44±2.60)只,其中成鸡(1.95±0.69)只和幼鸡(8.45±2.28)只.褐马鸡家族群偏向于阔叶林,避免针叶林;偏向于半阴半阳坡,避免阳坡和阴坡;偏向于下坡位和中坡位,避免上坡位;偏向于沟底,避免山脊和山坡;对坡度的利用没有选择性.对褐马鸡育雏期取食地利用样方和非利用样方进行比较,发现育雏期取食地具有距离水源和林间小路近,乔木层盖度和种类大、灌丛和草本密度小,灌木层和草本植物盖度小,落叶厚和裸地比例大的特征.对生境因子的主成分分析,前6个特征值的累积贡献率达到74.63%,可以较好地反映其家族群觅食地生境特征.根据载荷系数绝对值大小,将家族群取食地选择影响因子分别命名为成鸡应急因子、小鸡应急因子、食物丰富度因子、隐蔽因子和逃跑因子.

From May to June in 2006 the brood habitat of brown eared-pheasant （Crossoptilon mantchuricum） was investigated in Huanglongshan Nature Reserve,Huanglong County,Shaanxi Province,China. A total of twenty broods were observed. The brood size averaged 10.44±2.60,including adult pheasant （1.95±0.69） and infants （8.45±2.28 ）. Brown eared-pheasant brood preferred broadleaf forests,slope exposed to half sunny and half shady slope,mid and low slope location as well as gully and avoided conifer forests,sunny slopes and shady slopes,upper slopes,ridges and slope sides. Moreover they showed no preference for the slope degree. Compared with random plots,used sites were characterized by lower density,cover of shrub and grasses,heavier leaf-fallen layer,greater proportion of bareness and nearer distance to water and trail. Principal component analysis showed that the first 6 principal components accounted for 74.6% of the total variance among all habitat variables. According to the absolute value of coefficient,the 6 components were classified separately as an emergency factor of adult pheasant,an emergency factor of chickling,food abundance factor,sheltering class factor and escaping factor.