Variable Control of Island Communities: Productivity, Nutrients, Consumption and El Nino/Drought Events

这项工作研究了哪些因素决定了加利福尼亚湾关键种群的分布、丰度和多样性。与较大的岛屿或大陆相比，许多种类的昆虫、蜘蛛、蝎子、蜥蜴和哺乳动物在小岛屿和沿海地区异常密集。有几个因素很重要：生产力通过海岸漂移和鸟类群落从海洋生态系统流向陆地生态系统；岛屿的大小（其海岸线与面积的比例）；变化的陆地生产力；以及捕食者的存在和缺失。海洋和陆地食物网将通过研究海洋输入如何渗透内陆以及它如何影响关键物种来连接起来。陆地植物的初级生产力如何随着降水变化而变化（从干旱到与厄尔尼诺事件相关的暴雨），以及海鸟施肥引起的土壤养分差异，以及陆地系统如何对这种变化作出反应，都将被确定。本研究探讨了几个具有应用重要性的问题。首先，它分析了海洋输入对岛屿和陆地沿海社区的关键种群、食物网和生态系统的动态施加的潜在巨大影响。这是新颖而重要的，因为沿海社区覆盖了地球约8%的面积，容纳了超过65%的人类，并拥有不成比例的生物多样性和生产力。其次，本研究探讨了厄尔尼诺（一个主要的行星天气制造者）如何影响陆地群落的生产力和结构。第三，它说明了一个无处不在的过程：营养物、碎屑、猎物和消费者跨越栖息地边界的流动。最后，这个系统是岛屿和碎片化生境（如自然保护区）生态学的一般模型，每个都有不同的大小，每个都表现出不同的物种组合和与其他生境的相互联系。它还提供了对影响丰度和生物多样性的因素的一般理解。

9527888 Polis This work examines what factors determine the distribution, abundance, and diversity of key groups along the Gulf of California. Many species of insects, spiders, scorpions, lizards and mammals are extraordinarily dense on small islands and coastal areas compared to larger islands or the mainland. Several factors are important: productivity flowing from the marine to terrestrial ecosystems via shore drift and bird colonies; size of the island (its shoreline to area ratio); variable terrestrial productivity; and the presence/absence of predators. The marine and terrestrial food webs will be connected by examining how marine input penetrates inland and how it affects key species. How primary productivity by land plants changes with variable precipitation (drought to heavy rainfall associated with El Nino events) will be determined, as will differences in soil nutrients caused by seabird fertilization and how the terrestrial system responds to such changes. This research investigates several issues with applied importance. First, it analyzes the potentially great influence that marine input exerts on the dynamics of key populations, food webs, and ecosystems of island and terrestrial coastal communities. This is novel and important, since coastal communities cover about 8% of the earth and contain more than 65% of humans and a disproportionate amount of biodiversity and productivity. Second, this research addresses how El Nino, a major planetary weather maker, influences the productivity and structure of land communities. Third, it illustrates a ubiquitous process: the flow of nutrients, detritus, prey, and consumers across habitat boundaries. Finally, this system is a general model for the ecology of islands and fragmented habitats (e.g., nature reserves), each of different size, and each exhibiting different combinations of species and interconnections to other habitats. It also provides a general understanding of factors affecting abundance and biodiversity.