青海省河南蒙古族自治县高原鼠兔洞口空间分布格局及其成因研究

黄河源区位于我国青藏高原东北部，是重要的生态屏障和生物多样性宝库。高原鼠兔（Ochotona curzoniae）在黄河源区广泛分布，认识高原鼠兔时空分布特征对了解其在生态系统中的作用具有重要意义。采用无人机技术，通过自主研发的无人机航拍系统，于2016年8月、2017年8月、2017年12月、2018年5月多次在位于黄河源区的青海省黄南州河南县进行野外航拍工作，共布设了29个工作点（每个工作点单独设置航线，包含12～16个固定拍摄点），共计拍摄500余张定点航拍照片，每张照片覆盖地面35 m×26 m范围。同时，对工作点进行了相关地面调查。河南县高原鼠兔洞口分布异质性较大，分布极不均衡。鼠洞密度在2016—2017年间有增加趋势，由平均14.7个?亩-1增加到20.1个?亩-1。影响鼠洞分布的因素较为复杂，如气候、植被、放牧、土壤、招鹰架的布设及灭鼠等。就放牧强度与离水源地距离两点加以分析，结果表明在中等放牧强度下和与水源地有一定距离（50～200 m）的环境下鼠洞密度较高。

Distribution and cause of plateau pika(Ochotona curzoniae) burrows in Henan Mongolian Autonomous county, Qinghai Province

Source Region of Yellow River Basin is a core zone for ecological barrier and biodiversity treasury in Tibetan Plateau. Plateau pika (Ochotona curzoniae) is widely distributed in this region and exerts profound effects on the terrestrial ecosystem. Investigating spatial distribution of pika is important to understand the role of them played in the ecosystem. In this study, we investigated pika burrow density by UAV aerial photography and field measurement in Henan county, Huangnan Prefecture, Qinghai Province, Source Region of Yellow River Basin in August 2016, August 2017, December 2017 and May 2018. Totally, 29 work points (each work ponit includes 12-16 wayponits) were set and 500 aerial photographs were obtained. Each aerial photograph taken by UAV at a height of 20 m covers approximately 35 m × 26 m ground area. We found that the distribution of pika burrows was extreme heterogeneous and unbalanced. The pika burrow density increased from 14.7 in 2016 to 20.1 per mu in 2017. We concluded that the distribution of pika burrow was regulated by the combined factors, including climate, vegetation, grazing, soil, scaffold and deratization, etc. We also analyzed the relationships of pika burrow density with the grazing intensity and the distance from water sources. The results showed that the high pika burrow density was under moderate grazing intensity and at a distance of 50 to 200 m from the water source.