Williams Nicholas S G, Hahs Amy K, Morgan John W
Australian Research Centre for Urban Ecology, Royal Botanic Gardens, Melbourne, c/o School of Botany, University of Melbourne, Victoria 3010, Australia.
Ecol Appl. 2008 Mar;18(2):347-59. doi: 10.1890/07-0868.1.
Developing tools to predict the location of new biological invasions is essential if exotic species are to be controlled before they become widespread. Currently, alpine areas in Australia are largely free of exotic plant species but face increasing pressure from invasive species due to global warming and intensified human use. To predict the potential spread of highly invasive orange hawkweed (Hieracium aurantiacum) from existing founder populations on the Bogong High Plains in southern Australia, we developed an expert-based, spatially explicit, dispersal-constrained, habitat suitability model. The model combines a habitat suitability index, developed from disturbance, site wetness, and vegetation community parameters, with a phenomenological dispersal kernel that uses wind direction and observed dispersal distances. After generating risk maps that defined the relative suitability of H. aurantiacum establishment across the study area, we intensively searched several locations to evaluate the model. The highest relative suitability for H. aurantiacum establishment was southeast from the initial infestations. Native tussock grasslands and disturbed areas had high suitability for H. aurantiacum establishment. Extensive field searches failed to detect new populations. Time-step evaluation using the location of populations known in 1998-2000, accurately assigned high relative suitability for locations where H. aurantiacum had established post-2003 (AUC [area under curve] = 0.855 +/- 0.035). This suggests our model has good predictive power and will improve the ability to detect populations and prioritize areas for ongoing monitoring.
如果要在外来物种广泛传播之前对其进行控制，开发预测新生物入侵地点的工具至关重要。目前，澳大利亚的高山地区基本上没有外来植物物种，但由于全球变暖和人类活动加剧，面临着来自入侵物种的越来越大的压力。为了预测高入侵性的橙黄飞蓬（Hieracium aurantiacum）从澳大利亚南部博贡高平原现有的初始种群可能的扩散情况，我们开发了一个基于专家知识、空间明确、受扩散限制的栖息地适宜性模型。该模型将根据干扰、场地湿度和植被群落参数开发的栖息地适宜性指数，与一个使用风向和观测到的扩散距离的现象学扩散核相结合。在生成定义了整个研究区域橙黄飞蓬定殖相对适宜性的风险地图后，我们在几个地点进行了密集搜索以评估该模型。橙黄飞蓬定殖的最高相对适宜性位于初始侵染地的东南部。原生草丛草原和受干扰地区对橙黄飞蓬定殖具有较高的适宜性。广泛的实地搜索未能发现新的种群。使用1998 - 2000年已知种群的位置进行时间步评估，准确地为2003年后橙黄飞蓬已定殖的地点分配了高相对适宜性（曲线下面积[AUC] = 0.855 +/- 0.035）。这表明我们的模型具有良好的预测能力，将提高检测种群和确定持续监测重点区域的能力。
