区域尺度薇甘菊入侵分布的影响因子

Factors influencing Mikania micrantha invasion and distribution at regional scale

以深圳市宝安区为研究区,利用基于2007年IRS卫星影像数据得到的土地利用分类制图以及同年薇甘菊分布调查图、DEM等GIS数据,通过薇甘菊入侵/未入侵地区相关指标的对比性分析及Autologistic回归模型的构建,研究了区域尺度下薇甘菊入侵分布的重要影响因子。结果表明:(1)区域尺度下薇甘菊入侵地区与未入侵地区之间存在显著差异,地形特征及土地利用方式为显著影响因子,群落特征的影响不显著;(2)Autologistic回归模型显示出薇甘菊的入侵分布与其邻域果园密度及水体密度高度相关,模型结果具有较好的拟合精度,可以为薇甘菊入侵扩散重建及近期重点区域的防除决策提供参考依据。

Modeling the potential distribution of invasive plant species to implement effective prevention strategies is one of the major issues confronting rapidly urbanizing regions.This study focused on Mikania micrantha,the most problematic weed in the study site（Baoan District in Shenzhen,China）.Our goal was to determine the key impact factors associated with the weed＇s presence/absence information through the comparison analysis between the invasive and non-invasive sites as well as the construction of Autologistic regression model.Data analysis was based on the land-use classification map derived from IRS satellite imagery of 2007 and contemporary survey map of Mikania,while topographic data were obtained using DEM in a geographic information system（GIS）.The final conclusions are drawn from the research as follows：（1） At the regional scale,most topography and land use characteristics were significantly correlated with Mikania presence,whereas features of the local vegetation community revealed little influence;（2） Autologistic regression modeling demonstrated that the weed distribution was highly correlated with surrounding orchard density and water density,and this model showed a good performance of fitness,therefore,it could be used as a valuable tool for reconstructing the invasion process and assisting decision makers to target the locations at highest risk in the near future.