基于MaxEnt模型的长株潭狗尾草生境适宜性评价

Habitat Suitability Evaluation of Setariaviridis(L.)Beauv.in the Chang-Zhu-Tan Urban Agglomeration Based on MaxEnt Model

在景观破碎化前提下,生境适宜性评价对野生植物的保护与管理具有重要意义。为了解长株潭城市群狗尾草的生境状况,利用2018年野外采集的狗尾草分布数据和5个可能对其分布影响较高的主导环境因子(高程、土地利用类型、道路、坡度、植被覆盖类型)通过ArcGIS软件进行图层预处理,统一了图层坐标系、像元大小以及范围,运用最大熵模型(MaxEnt)模拟了其在长株潭城市群的潜在生境分布状况。结果显示:①MaxEnt模型对长株潭城市群狗尾草潜在生境模拟的结果表现出较高的精准度(AUC=0.883);②长株潭城市群狗尾草的潜在分布区主要集中在长沙市天心区、雨花区、芙蓉区、开福区、岳麓区东部、望城区中北部、长沙县中部偏西、湘潭市雨湖区东南部、岳塘区西南部、湘潭县北部、湘乡市中部,株洲石峰区、天元区东部、醴陵市中部地区;③上述5个主导环境因子能解释极大部分的长株潭城市群狗尾草的分布,其中高程、土地利用类型、道路、植被覆盖类型是影响长株潭城市群潜在生境分布的主要环境因子,坡度对其影响效果不强。明确了狗尾草在长株潭城市群的分布状况以及关键环境影响因子,为下一步制定保护和生境管理以及城市景观破碎化研究提供参考。

Under the premise of landscape fragmentation,habitat suitability evaluation is of great significance to the protection and management of wild plants.In order to understand the habitat status of Setariaviridis(L.)Beauv in the Chang-Zhu-Tan urban agglomeration,the distribution data of Setariaviridis(L.)Beauv collected in the field in 2018 and five dominant environmental factors(elevation,land use type,road,slope and vegetation cover types)that may have a high impact on its distribution were used.The layer is preprocessed by ArcGIS software.The coordinate systems,pixel size and range of the layer are unified,and the maximum entropy model(MaxEnt)is used to simulate its potential habitat distribution in the Chang-Zhu-Tan urban agglomeration.The results showed that:①The MaxEnt model showed high accuracy(AUC=0.883)for the simulation results of the potential habitat of Setariaviridis(L.)Beauv in the Chang-Zhu-Tan urban agglomeration.②The potential distribution areas of Setariaviridis(L.)Beauv in the urban agglomeration of Changsha,Zhuzhou and Xiangtan are mainly concentrated in Tianxin District,Yuhua District,Furong District,Kaifu District,the eastern part of Yuelu District,the central and northern part of Wangcheng District,the central and western part of Changsha County,the Yuhua District of Xiangtan City,southwestern Yuetang District,northern Xiangtan County,central Xiangxiang City,Zhuzhou Shifeng District,eastern Tianyuan District,and central Liling City.③The above five dominant environmental factors can explain most of the distribution of foxtail in the Chang-Zhu-Tan urban agglomeration,among which elevation,land use types,road,and vegetation cover types are the main environmental factors affecting the potential habitat distribution of the Chang-Zhu-Tan urban agglomeration.The slope has little effect on it.To sum up,this study clarified the distribution of Setariaviridis(L.)Beauv in the Chang-Zhu-Tan urban agglomeration and key environmental factors,and provided theoretical basis for the next step to formulate protection and habitat management and landscape fragmentation research.