基于MAXENT模型的丹顶鹤营巢生境适宜性分析——以扎龙保护区为例

明确物种繁殖栖息地的潜在分布对于受胁物种的保护与科学管理具有十分重要的意义。扎龙保护区是国际濒危物种丹顶鹤西部迁徙种群的主要繁殖地之一,近年来繁殖种群数量波动较大。通过GIS空间技术平台,利用MAXENT模型,结合2012—2013年丹顶鹤(Grus japonensis)营巢分布点和环境特征变量,对扎龙保护区丹顶鹤营巢生境的适宜性进行了分析。结果表明:模型的评价效果达到优秀水平(训练集AUC=0.901);绿度(34.9%)、距道路距离(17.1%)、土壤湿度(16.3%)、海拔(15.7%)是丹顶鹤营巢生境的主要环境特征变量;核心区中部和南部是丹顶鹤主要的适宜营巢分布区,缓冲区和实验区有少量的适宜营巢区分布,丹顶鹤适宜营巢生境面积为35857.35hm~2,占保护区总面积的17.07%。建议在重点管理核心区的同时,对缓冲区和实验区的小面积芦苇沼泽给予更多关注。

Nesting habitat suitability analysis of red-crowned crane in Zhalong Nature Reserve based on MAXENT modeling

Breeding habitat suitability analysis has significance for the timely conservation and scientific management of threatened species. Zhalong Nature Reserve is one of the main breeding sites of the western group red-crowned crane (Grus japonensis) migratory population, with a large, dynamic breeding population. With the objective of predicting the nesting habitat of red-crowned crane in Zhalong Nature Reserve, we obtained nesting occurrence records for this species from the study area collected from 2012-2013, extracted the environmental factors from the thematic mapper (TM) image of Zhalong Nature Reserve in 2013. We analyzed the nesting habitat suitability of red-crowned crane by the combined use of a GIS and MAXENT model. The results showed that the accuracy of the MAXENT model was excellent (training data area under the curve=0.901). The greenness vegetation index (34.9%), man-made interference (namely, the distance to frequently disturbed zones from human activity, 17.1%), soil wetness index (16.3%), and elevation (15.7%) were the main environmental factors influencing the nesting habitat selection of red-crowned crane. The central and south regions of the core zone were the main suitable nesting zones, and there was a small area of suitable habitat in the buffer zone and the experimental zone; the suitable nesting habitat area was 35857.35 hm², representing about 17.07% of the whole reserve. The results showed that the core zone is the most important management zone for red-crowned crane nesting, and the reserve should also pay more attention to the small reed marsh area in the buffer zone and the experimental zone.