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

岛屿社区的变量控制：生产力、养分、消费和厄尔尼诺/干旱事件

• 批准号: 9527888
• 负责人: Gary Huxel
• 金额: $ 29.73万
• 依托单位: Vanderbilt University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-03-15 至 1999-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9527888&HistoricalAwards=false
• 关键词: Variable; Control; Island; Communities; Productivity

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.

9527888 Polis这项工作研究了什么因素决定了沿着加州湾的主要群体的分布、丰度和多样性。 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比在大岛屿或大陆上更为密集。 有几个因素很重要：通过海岸漂流和鸟类群落从海洋生态系统流向陆地生态系统的生产力;岛屿的大小（海岸线与面积之比）;陆地生产力的变化;以及有无捕食者。 海洋和陆地食物网将通过研究海洋输入如何渗透到内陆以及如何影响关键物种而联系起来。 将确定陆地植物的初级生产力如何随着降水量的变化（干旱到与厄尔尼诺现象有关的暴雨）而变化，还将确定海鸟施肥造成的土壤养分差异以及陆地系统如何对这种变化作出反应。 本研究探讨了几个具有应用价值的问题。 首先，它分析了潜在的巨大影响，海洋输入施加的关键种群，食物网，岛屿和陆地沿海社区的生态系统的动态。 这是一个新的和重要的，因为沿海社区覆盖了大约8%的地球，包含了超过65%的人类和不成比例的生物多样性和生产力。 其次，这项研究解决了厄尔尼诺现象，一个主要的行星天气制造者，如何影响土地社区的生产力和结构。 第三，它说明了一个普遍存在的过程：营养物质、碎屑、猎物和消费者跨越栖息地边界的流动。 最后，该系统是岛屿和破碎生境生态学的一般模型（例如，自然保护区），每个保护区的大小不同，并且每个保护区都表现出不同的物种组合以及与其他栖息地的相互联系。 它还提供了对影响丰度和生物多样性的因素的一般了解。