The Effects of Pulsed Subsidies on Island Food Webs

资源可获得性的时空变化可对自然群落的结构和动态产生深远影响。资源脉冲是资源可获得性的短期增加；在巴哈马群岛的岛屿上，在大风暴期间沉积的海藻对捕食性蜥蜴来说是一种重要的资源脉冲或补贴。该项目将结合实验和观察研究，以确定海藻补贴如何塑造岛屿群落，这些群落主要由植物、草食动物、网络蜘蛛和蜥蜴组成。主要目标是了解群落的反应如何与海藻脉冲的频率和幅度、蜥蜴等消费者在脉冲资源区域聚集的能力、资源对捕食者替代猎物的间接影响以及这些复杂相互作用的各种表现途径--例如捕食和营养丰富--有何不同。为了实现这些目标，将启动控制海藻脉冲和蜥蜴密度的实验。这些实地研究将与数学建模相结合，以发展社区对资源脉冲的反应的一般理论。通过与加州大学戴维斯·博哈特昆虫学博物馆和巴哈马环境之友的伙伴关系，该项目将整合对K-12学生的宣传和教育。研究人员将在课堂上发表演讲，培训教师将科学融入他们的课程，并通过网络开发和分发教材。这项研究将通过与一名日本科学家的合作来加强国际合作。它还将通过让来自代表性不足群体的本科生和研究生参与研究过程，促进发展多样化的国家科学界和劳动力队伍。结果将有助于更坚定地理解快速环境变化的生态后果。由于过度捕捞和富营养化等人为干扰促进了向以藻类为主的海洋生态系统的转变，随着气候变化导致大西洋风暴更加频繁和强烈，海洋资源脉动或补贴对岛屿和沿海社区的影响预计将加剧。

Spatial and temporal variation in the availability of resources can have profound effects on the structure and the dynamics of natural communities. Resource pulses are short-term increases in resource availability; on islands in the Bahamas, seaweed deposited during large storms represents an important resource pulse, or subsidy, for predatory lizards. This project will combine experimental and observational studies to determine how seaweed subsidies shape island communities, which are comprised mainly of plants, herbivores, web spiders, and lizards. Major goals are to understand how community responses differ with the frequency and magnitude of seaweed pulses, the ability of consumers such as lizards to aggregate in areas with pulsed resources, the indirect effects of resources on predators' alternative prey, and the various pathways - for example, predation versus nutrient enrichment - by which these complex interactions are manifested. Experiments will be initiated that manipulate both seaweed pulses and lizard densities to address these goals. These field studies will be integrated with mathematical modeling in order to develop a general theory of community responses to resource pulses. Through partnerships with the University of California at Davis Bohart Museum of Entomology and Friends of the Environment in the Bahamas, the project will integrate outreach and education for K-12 students. Researchers will give classroom presentations, train teachers to integrate science in their curriculum, and develop and distribute teaching materials via the web. The research will strengthen an international partnership via collaboration with a Japanese scientist. It also will contribute to the development of a diverse national scientific community and workforce by involving undergraduate and graduate students from under-represented groups in the research process. Results will contribute to a firmer understanding of the ecological consequences of rapid environmental change. As anthropogenic disturbances such as overfishing and eutrophication facilitate shifts towards algae-dominated marine ecosystems, and as climate change causes more frequent and intense Atlantic storms, the effects of marine resource pulses or subsidies on island and coastal communities are predicted to intensify.