基于无人机遥感的三江源国家公园藏野驴种群数量及生境时空变化研究

藏野驴（Asinus kiang）是青藏高原特有物种，我国一级野生保护动物。三江源国家公园黄河源园区是藏野驴的主要栖息地之一，而生物多样性保护也是国家公园的重要职能，准确了解藏野驴的种群数量及栖息地变化无论是从野生动物保护还是从国家公园建设指导来看均具有重要意义。以三江源国家公园黄河源园区为研究区，利用无人机遥感技术开展藏野驴种群数量调查工作，在此基础上利用选择指数与因子分析揭示藏野驴的生境选择偏好，识别其适宜栖息地范围。并深入探讨近20年藏野驴适宜栖息地的时空变化特征，探讨驱动因素。结果表明：（1）无人机可以有效识别藏野驴个体，在调查样带内共发现藏野驴252头，经过推算2017年春季三江源国家公园黄河源园区内共有藏野驴20989头。（2）藏野驴倾向于选择距居民点1 km以外，距道路1-3 km范围内，距水源1 km以内，且植被覆盖度介于0.4-0.8之间的坡度小于5°的平坦区域做为栖息地。（3）2000-2018年间，三江源国家公园黄河源园区内的藏野驴适宜生境面积增加了330.76 km²，达到4747.10 km²，面积占比增加1.73%，达到了24.85%。这主要是气候变化与人类活动协同作用下导致的水体扩张与植被覆盖度增加驱动的。此外，虽然道路的扩张仅限制了小面积的适宜栖息地增加，但可能造成栖息地连通性下降等更为严重的后果。本研究证明了无人机遥感技术在青藏高原等开阔区域进行野生动物调查及栖息地研究的可行性与优势，相关技术方法与研究成果可为三江源国家公园生物多样性保护工作提供参考与支撑。

Population of kiangs and spatio-temporal variation of its habitat in Sanjiangyuan National Park based on unmanned aerial vehicle remote sensing

The kiangs (Asinus kiang) is a unique species on the Qinghai-Tibet Plateau and the first-class protected wild animal in China. The Yellow-River-Resource Park of Sanjiangyuan National Park is one of the main habitats of kiangs, and biodiversity protection is one of its basic function. Thus, it is of great significance to accurately know the population and habitat change of kiangs not only from the perspective of wildlife protection but also from the guidance of national park construction. In this study, the Yellow-River-Resource National Park was chosen as the study area, and unmanned aerial vehicle (UAV) remote sensing technology was used to carry out the population survey of kiangs. Furthermore, the line transects sampling method which is usually used for ground investigations was carried out in this study for the estimation of kiangs'' population, and the selection index and factor analysis were used to reveal the habitat selection preference of the kiangs and their suitable habitat range was identified. The spatial and temporal variation characteristics of suitable habitat of kiangs in the past 20 years as well as the driving factors were discussed. Results showed that:(1) the individual kiangs could be effectively identified in UAV images with a spatial resolution of 4-7 cm. A total of 252 kiangs were found in the survey transection. It was estimated that there were 20989 kiangs in the Yellow-River-Resource National Park in spring 2017. (2) The kiangs preferred flat areas with slope less than 5° and vegetation coverage between 0.4 and 0.8, which were 1 km away from settlements, 1-3 km away from roads and 1 km within water. (3) From 2000 to 2018, the area of suitable habitat for kiangs in the Yellow-River-Resource Park of Sanjiangyuan National Park increased 330.76 km² and reached 4747.10 km² in total, the proportion increased from 23.12% to 24.85%. This was mainly driven by the expansion of water body and the increase of vegetation coverage caused by the synergistic effect of climate change and human activities. In addition, although road expansion only limited the increase of suitable habitat in small areas, it might have more serious consequences, such as reduced habitat connectivity. This study proved the feasibility and advantages of UAV remote sensing technology for wildlife investigation and habitat research in open areas such as the Qinghai-Tibet Plateau. The relevant technologies, methods and research results can provide reference and support for biodiversity protection in Sanjiangyuan National Park.