Spatiotemporal variation in the impacts of biological invasions

生物入侵影响的时空变化

• 批准号: RGPIN-2016-03918
• 负责人: Ricciardi, Anthony
• 金额: $ 3.79万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=614720
• 关键词: Spatiotemporal; variation; impacts; biological; invasions

Nonindigenous species are being discovered in aquatic ecosystems at increasing rates worldwide. Many of these invasions appear to have minor ecological effects, while others cause substantial changes to biodiversity and food webs. Our capacity to predict which invasion will have undesirable consequences is impeded by context dependence: invader impacts vary across space and time under the influence of local environmental conditions. The long-term goal of my research program is to develop models that explain and predict the impacts of biological invasions. The aim of this proposal is to explore context dependency by testing hypotheses that explain spatiotemporal variation in impact. Three major hypotheses are the focus of this proposal: 1) the Invasion Front Hypothesis predicts that more recent invaders such as those at the front of a spreading population will exert higher impacts associated with higher feeding rates and heightened aggression, whereas individuals from longer established core populations will be less voracious and aggressive; 2) the Environmental Matching Hypothesis predicts that an invader will produce stronger per capita effects in an abiotic environment that closely matches its physiological optimum; and 3) the Resource Consumption Hypothesis predicts that the most disruptive invasive species have higher and more efficient resource consumption rates than those species without extensive invasion or impact histories. I will use a combination of lab and field experiments on fishes and crustaceans in a variety of freshwater and marine habitats as model systems. Treatments with increasing prey abundances will be offered to invasive predators, and the number of prey consumed will be related to prey supplied in a classical functional response experiment that will allow us to quantify per capita effects. Context dependency will be incorporated by comparing per capita effects across gradients of temperature, water chemistry and water velocity. These lab experiments will be complemented by field mesocosm experiments involving reciprocal transplants between the invasion front and core sites where the invader is well established. Field sites will incorporate natural environmental gradients. In testing these hypotheses, my lab will identify and develop some valuable model systems that can be used to inform invasion theory, and we will demonstrate how environmental context can be incorporated into risk assessment.

在世界范围内，水生生态系统中发现的非本地物种越来越多。许多这些入侵似乎有轻微的生态影响，而其他人造成重大变化的生物多样性和食物网。我们预测哪种入侵会产生不良后果的能力受到环境依赖的阻碍：入侵者的影响在当地环境条件的影响下在空间和时间上各不相同。我的研究计划的长期目标是开发解释和预测生物入侵影响的模型。这项建议的目的是通过测试解释影响的时空变化的假设来探索上下文依赖性。主要有三个假说：1）入侵前沿假说（InvasionFrontiesHypothesis）认为，处于扩散种群前沿的新入侵者会产生更大的影响，并伴随着更高的摄食率和更强的攻击性，而来自建立时间较长的核心种群的个体则不那么贪婪和具有攻击性;（2）环境匹配假说认为，入侵者在与其生理最适条件密切匹配的非生物环境中，会产生更强的人均效应; 3）资源消耗假说预测，最具破坏性的入侵物种比那些没有广泛入侵或影响历史的物种具有更高和更有效的资源消耗率。 我将使用实验室和现场实验相结合的鱼类和甲壳类动物在各种淡水和海洋栖息地作为模型系统。治疗与增加猎物丰度将提供给入侵的捕食者，和猎物消耗的数量将有关的经典功能反应实验，将使我们能够量化人均效应的猎物。将通过比较温度、水化学和水流速度梯度的人均影响，纳入背景依赖性。这些实验室实验将补充现场围隔实验，涉及相互移植之间的入侵前线和核心网站，入侵者是建立良好的。实地地点将纳入自然环境梯度。 在测试这些假设，我的实验室将确定和开发一些有价值的模型系统，可用于通知入侵理论，我们将演示如何环境背景可以纳入风险评估。