Prioritising weeds for control and deciding upon the type of control and its associated investment are fundamental to weed management planning. Risk analysis is central to this process, combining the activities of risk assessment, risk management and risk communication. Risk assessment methodology has a rich history, but management feasibility has typically been a secondary matter, dealt with separately or not at all. Determinants of management feasibility for weeds include the stage of invasion, weed biology, means of control and cost of weed control. Here, we describe a simple weed risk analytical screen that combines risk assessment with species traits that influence management feasibility. We consider stage of invasion, species biological/dispersal characteristics and plant community invasibility in a preliminary analysis of the risk posed by the non-native plant species on Christmas Island in the Indian Ocean. For each of 31 high-risk species considered to be ineradicable under existing funding constraints, we analyse the risk posed to two major plant communities: evergreen closed-canopy rainforest and semi-deciduous scrub forest. Weed risk ratings are combined with ratings for species-intrinsic feasibility of containment (based on a measure that combines time to reproduction with potential for long distance dispersal) to create preliminary rankings for containment specific to each community. These rankings will provide a key input for a more thorough analysis of containment feasibility – one that considers spatial distributions/landscape features, management aspects and the social environment. We propose a general non-symmetric relationship between weed risk and management feasibility, considering risk to be the dominant component of risk analysis. Therefore, in this analysis species are ranked according to their intrinsic containment feasibility within similar levels of risk to produce an initial prioritisation list for containment. Shade-tolerant weeds are of particular concern for the closed-canopy evergreen rainforest on Christmas Island, but a greater diversity of weeds is likely to invade the semi-deciduous scrub forest because of higher light availability. Nevertheless, future invasion of both communities will likely be conditioned by disturbance, both natural and anthropogenic. The plant communities of Christmas Island have undergone significant fragmentation because of clearing for phosphate mining and other purposes. With a substantial number of invasive plant species firmly established and having the potential to spread further, minimising future anthropogenic disturbance is paramount to reducing community invasibility and therefore conserving the island’s unique biodiversity.

中文翻译：

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杂草风险分析筛选有助于确定入侵植物群的优先级以进行遏制

优先控制杂草并决定控制类型及其相关投资是杂草管理计划的基础。风险分析是这一过程的核心，结合了风险评估、风险管理和风险沟通的活动。风险评估方法有着悠久的历史，但管理可行性通常是次要问题，单独处理或根本不处理。杂草管理可行性的决定因素包括入侵阶段、杂草生物学、控制手段和杂草控制成本。在这里，我们描述了一个简单的杂草风险分析屏幕，它将风险评估与影响管理可行性的物种特征相结合。我们考虑入侵的阶段，印度洋圣诞岛上非本地植物物种风险的初步分析中的物种生物学/扩散特征和植物群落入侵性。对于被认为在现有资金限制下无法根除的 31 种高风险物种中的每一种，我们分析了对两个主要植物群落构成的风险：常绿封闭树冠雨林和半落叶灌木林。杂草风险评级与物种固有的遏制可行性评级相结合（基于将繁殖时间与远距离传播潜力相结合的衡量标准），以创建针对每个社区的遏制的初步排名。这些排名将为更彻底地分析遏制可行性提供关键输入——考虑空间分布/景观特征，管理方面和社会环境。我们提出了杂草风险和管理可行性之间的一般非对称关系，将风险视为风险分析的主要组成部分。因此，在该分析中，物种根据其在相似风险水平内的内在遏制可行性进行排名，以产生初步的遏制优先级列表。耐阴杂草对圣诞岛上的封闭树冠常绿雨林尤为关注，但由于光照充足，更多种类的杂草很可能侵入半落叶灌木林。然而，未来两个社区的入侵很可能会受到自然和人为干扰的影响。由于磷矿开采和其他目的的清理，圣诞岛的植物群落经历了显着的破碎。由于大量入侵植物物种已牢固建立并有进一步传播的潜力，最大限度地减少未来的人为干扰对于减少社区入侵并因此保护岛上独特的生物多样性至关重要。