普氏原羚生境选择的数量化分析

QUANTITATIVE ANALYSIS OF THE HABITAT SELECTION BY PROCAPRA PREZWALSKII

1998年 8月至 1 999年 8月 ,在湖东种羊场地区开展了普氏原羚生境选择的研究。在湖东—克图沙丘和草原交界处沿约 3 0km的样线开展种群调查 ,在调查过程中 ,共发现 5 82只普氏原羚。在研究中选择了 8类与普氏原羚生境选择相关的生态因子 :植被类型、食物丰富度、草原围栏、隐蔽条件、人为干扰、距公路距离、距沙丘距离和距农业用地距离 ,研究了普氏原羚的生境选择。在研究中 ,将这些生态因子分别分成 3个等级 ,进行回归分析 ,建立普氏原羚在不同生境中出现的概率的预测性方程。通过对生态因子和普氏原羚在不同生境中出现的概率进行方差分析 ,判断影响普氏原羚生境选择的主要生态因子是人为干扰和围栏 ,其次为食物丰富度、距沙丘距离和农业用地距离 ,植被类型。

Habitat selection by Procapra przewalskii was studied from August 1998 to August 1999 in the Hudong-Ketu region, Qinghai province, China. We set out transects of about 30 km long in the ecotone of the Hudong-Ketu desert and carried out field surveys along those transects. During our field surveys, we found 582 Prezwalski′s gazelles.We recorded the probability of Procapra prezwalskii using a specific habitat and the habitat parameters such as vegetation type, food abundance, pasture fence, shelter condition, human disturbance, distance from road, distance from sandbank, distance from agricultural land during the field investigations.The information was used to establish mathematical model to forecast gazelles visiting probabilities to those habitats. These habitat factors were divided into three ranks and analyzed by using the multiple regressions. Based on the analyses, we concluded: (1) Among the eight ecological factors, the pasture fence and the human disturbance were the two main factors that influenced the habitat selection by Procapra prezwalskii; (2) Food abundance, distance from sandbank or the distance from the agricultural land were ranked as the secondary factors that influenced habitat selection by Procapra prezwalskii; and (3) Vegetation type, shelter condition, especially a new road had little influence on the habitat selection by Procapra prezwalskii.