Species Diversity and Abundance in Insular Systems

岛屿系统的物种多样性和丰富度

• 批准号: 9615151
• 负责人: Thomas Schoener
• 金额: $ 35.01万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-03-01 至 2000-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9615151&HistoricalAwards=false
• 关键词: Species; Diversity; Abundance; Insular; Systems

ABSTRACT 96-15151 Schoener Species Diversity and Abundance in Insular Systems This is a long-term experimental and observational study of food webs in islands of the Bahamas. A particular species in a food web may affect other species' abundances directly, via predation (predators reduce prey and, correspondingly, prey increase predators) or indirectly, via other species (e.g. predators may help plants indirectly by eating their herbivores). Previous experiments manipulated smaller predators to determine their direct and indirect effects. The proposed two experiments manipulate larger predators. First, large lizards will be introduced to places having smaller lizards. Second, birds and smaller lizards will be excluded in a crossed design. The two types of larger predators should differ fundamentally in their effects, particularly on plants: the former eat smaller predators, whereas birds also eat prey of the smaller predators, especially herbivorous insects. Additionally, immigrations (natural "introductions") and extinctions (natural "removals") on over 100 islands will be monitored to determine their frequency and long-term effects.

这是一项对巴哈马群岛食物网的长期实验和观察研究。食物网中的特定物种可能通过捕食（捕食者减少猎物，相应地，猎物增加捕食者）直接影响其他物种的丰度，也可能通过其他物种间接影响其他物种（例如，捕食者可能通过捕食食草动物间接帮助植物）。先前的实验操纵较小的掠食者来确定它们的直接和间接影响。提出的两个实验操纵大型捕食者。首先，大型蜥蜴将被引入有较小蜥蜴的地方。其次，鸟类和较小的蜥蜴将被排除在交叉设计之外。这两种大型捕食者的作用应该是根本不同的，尤其是对植物的影响：前者以较小的捕食者为食，而鸟类也以较小捕食者的猎物为食，尤其是食草昆虫。此外，将监测100多个岛屿上的移民（自然“引进”）和灭绝（自然“清除”），以确定其频率和长期影响。