The Effects of Pulsed Subsidies on Island Food Webs

资源可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。资源脉动是指可用资源的短期增加；在巴哈马群岛上，大风暴期间沉积的海藻代表了掠食性蜥蜴的重要资源脉冲或补贴。该项目将结合实验研究和观察研究，以确定海藻补贴如何影响主要由植物、食草动物、网蜘蛛和蜥蜴组成的岛屿群落。主要目标是了解海藻脉冲的频率和大小如何影响群落的反应，蜥蜴等消费者聚集在脉冲资源区域的能力，资源对捕食者替代猎物的间接影响，以及各种途径-例如，捕食与营养富集-通过这些复杂的相互作用表现出来。将启动实验，操纵海藻脉冲和蜥蜴密度来实现这些目标。这些实地研究将与数学模型结合起来，以便发展社区对资源脉动反应的一般理论。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合作，该项目将把对K-12学生的推广和教育结合起来。研究人员将在课堂上做报告，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，加强国际伙伴关系。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，促进多样化的国家科学界和劳动力的发展。研究结果将有助于更坚定地了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，并且由于气候变化导致大西洋风暴更加频繁和强烈，预计海洋资源脉冲或补贴对岛屿和沿海社区的影响将加剧。

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.