基于Maxent模型的越冬白头鹤适宜生境预测

Prediction of suitable habitat for overwintering hooded cranes(Grus monacha) based on Maxent modeling

依据2013—2014年冬季野外调查的白头鹤分布点数据,结合2011—2015年间中国观鸟记录中心和已公开发表的相关文献中记录的白头鹤分布点信息,基于气候、地形、水系、土地利用类型和人类干扰5类环境因子,应用Maxent模型分析了安徽省越冬白头鹤适宜生境分布及影响其分布的主要环境因子,并结合已建自然保护区对白头鹤适宜生境进行保护空缺分析。结果表明,模型预测结果达优秀水平;距主要水源距离、1月份平均最低温、12月份平均最低温和距主要道路距离是影响白头鹤分布的主要环境因子,对模型的综合贡献值分别为45.3%、21.4%、19.3%和7.6%。白头鹤适宜生境主要分布在升金湖上湖和菜子湖,少量分布在龙感湖沿岸、武昌湖东岸及其东部的长江干流沿岸,其中核心适宜生境的总面积为45 980 hm2。空缺分析表明,已建自然保护区覆盖了60.1%的核心适宜生境,尚有18 346 hm2的核心适宜生境处于保护区之外,需要在重点管理保护区的同时,对保护区之外的核心适宜生境给予更多关注。

In this study, the Maxent model was used to predict the suitable habitat distribution for the hooded crane in Anhui province and the major environmental factors affecting such a distribution based on the occurrence data of the species and environmental factors. A gap analysis was conducted on the existing nature reserves. The occurrence data were collected from the winter filed survey in 2013-2014, China Bird Report and relevant litera- tures published in 2011-2015. The environmental factors include climate, terrain, river system, landuse type and human disturbance. The results showed that the model evaluation results was ideal, and the major evironmental factors influencing the distribution of the hooded crane included the distance from main water source, the average minimum temperature in January, the average minimum temperature in December and the distance from main roads, with a contribution of 45.3%, 21.4%, 19.3% and 7.6%, respectively. The suitable habitat for the hooded crane was mainly distributed in the upper Lake of Shengjin Lake and Caizi Lake and a small amount of the habitat was distributed along Longgan Lake, in the east bank of Wuchang Lake, and along the mainstream of Yangtze River in its east. The total area of core suitable habitat was 45 980 hm2. The Gap analysis showed that 60.1% of the core suitable habitat of the hooded crane was protected by natural reserves. There are 18 346 hm2 core suitable habitat uncovered bv these reserves： therefore more attention shall be oaid to suitable habitats outside the reserves.