无人机遥感调查黄河源玛多县岩羊数量及分布

本研究于2017年利用无人机航拍调查对黄河源玛多县县域内的岩羊种群数量进行了估算,并对其分布规律进行了研究。无人机航拍共获取影像23784张,有效面积326.6 km^2,通过目视解译,获取样带内的岩羊种群数量为203只,种群密度为0.6215只/km^2。通过推算,得到玛多县岩羊种群数量为8968只。对玛多县岩羊分布位置与环境因子的分析结果显示:岩羊偏好于选择海拔为4100～4200 m、距公路大于3 km、距悬崖峭壁200 m以内的区域活动。本研究利用无人机航拍样带调查估算黄河源玛多县岩羊种群数量与密度,并结合ArcGIS软件对其生境进行分析,将3S技术与野生动物调查相结合,为青藏高原地区大型野生动物相关研究提供了新思路。

Using UAV remote sensing for a population census of blue sheep (Pseudois nayaur) in Maduo county,source region of the Yellow River

In this study, Maduo county, the source region of the Yellow River, was selected as the research area. In 2017, UAV aerial survey was used to estimate the population of the blue sheep (Pseudois nayaur) and its distribution. The effective area of aerial surveys was 326.6 km², and 23784 images were acquired. The population in the survey transect was 203, which was identified visually on computer monitors by human observers, and the density was 0.6215/ km². A total of 12 groups of blue sheep were found in the transects, of which 6 groups had a cluster size of 2-10, accounting for 50% of the total. Estimation of population of blue sheep in Maduo county was 8968, which was based on the relationship of different types of grassland area between transects and the whole county. In this way, the area of non-vegetation types (such as bare stone gravel, water bodies, glaciers, towns, high-speed and national roads) is deducted, and the influence of human disturbance is considered. This avoided overestimation of the blue sheep population. The relationship between the distribution density of blue sheep and ecological factors of habitat was analyzed. Results show that blue sheep preferred an area within 1 km from rural settlements, 3 km away from roads, 1-3 km from water sources, within 200 m from the cliff and with an elevation of 4100-4200 m, vegetation coverage of 0-0.4, slope over 5°, vegetation type of Stipa purpurea + Subordinate grass and Kobresia pygmaea. The environmental factors of the blue sheep habitat may have a correlation with each other, in order to identify the environmental factors that have a major impact on the choice of habitat, and describe the preference more accurately, principal component analysis was carried out. The results showed that altitude, distance from the road and distance from the cliff were the main environmental factors affecting the choice of habitat of blue sheep. In this study, a UAV aerial sampling survey was conducted to estimate the population and density of the blue sheep in the study county. Aided by ArcGIS, the habitat was analyzed. The combination of 3S technology and wildlife surveys provides a new idea for the research on wildlife in the Tibetan Plateau.