Collaborative Research: The structure of arthropod food webs: consequences of nutrient-loading scenarios for productivity, trophic composition and food-chain length.

合作研究：节肢动物食物网的结构：营养负荷情景对生产力、营养成分和食物链长度的影响。

• 批准号: 1026000
• 负责人: Shannon Murphy
• 金额: $ 40万
• 依托单位: University of Denver
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-12-01 至 2016-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1026000&HistoricalAwards=false
• 关键词: Collaborative; Research; structure; arthropod; food

The effects of contrasting nutrient-input regimes on food-web structure in natural habitats remain poorly understood, despite the increasing fraction of landscapes experiencing nutrient runoff from agriculture and development. The intellectual merit of this project lies in its expansion of food-web theory to include complex nutrient dynamics that affect not only plant productivity but also interactions among consumers. The investigators will examine the effects of nutrient subsidies on food web dynamics in coastal salt marshes dominated by Spartina cordgrasses using a blend of manipulative field experiments and surveys of marshes that vary in nitrogen inputs. The long-term goal is to understand the relationship between primary productivity and food chain length and trophic composition in a system characterized by extensive omnivory and intra-guild predation.The broader impacts of this study extend beyond the testing and development ofecological theory. Because coastal wetlands play a critical role in the ecology and geology of wave-protected shorelines and are the nursery grounds for commercial fish and shellfish, their conservation is of major concern. Urban development and agriculture are jeopardizing these wetlands; nitrogen runoff increases plant growth, which subsequently has profound effects on all other salt marsh inhabitants. The resilience of salt marshes to repeated bouts of nitrogen addition is poorly understood. The proposed research will provide diverse educational opportunities for a postdoctoral researcher, graduate and undergraduate students. The investigators plan to participate in the District of Columbia Summer Youth Employment Program to hire two high school students from the metropolitan Washington, DC area each summer. This program matches residents of the District of Columbia with employers so that the students may gain exposure to new career opportunities.

对比营养投入制度对自然栖息地食物网结构的影响仍然知之甚少，尽管越来越多的景观经历营养径流从农业和发展。这个项目的智力价值在于它扩展了食物网理论，包括复杂的营养动态，不仅影响植物生产力，而且影响消费者之间的相互作用。研究人员将研究营养补贴对沿海盐沼食物网动态的影响，主要由米草，使用混合的操纵性田间实验和调查的沼泽，不同的氮输入。长期目标是了解初级生产力与食物链长度和营养组成之间的关系，在广泛的杂食性和行会内捕食系统的特点。这项研究的更广泛的影响超出了生态理论的测试和发展。由于沿海湿地在受波浪保护的海岸线的生态和地质方面发挥着关键作用，并且是商业鱼类和贝类的育苗场，因此它们的保护是主要关注的问题。城市发展和农业正在危及这些湿地;氮径流增加植物生长，随后对所有其他盐沼居民产生深远影响。 盐沼对氮的反复施加的恢复能力还知之甚少。 拟议的研究将为博士后研究人员，研究生和本科生提供多样化的教育机会。调查人员计划参加哥伦比亚特区暑期青年就业计划，每年夏天从大都市华盛顿地区雇佣两名高中生。该计划将哥伦比亚特区的居民与雇主相匹配，以便学生可以获得新的职业机会。