Spatial-Temporal Dynamics of Brant Herbivore Interactions and Ecosystem Processes in Coastal Tundra of the Yukon-Kuskokwim Delta in Western Alaska

阿拉斯加西部育空-库斯科奎姆三角洲沿海苔原布兰特草食动物相互作用和生态系统过程的时空动态

• 批准号: 9985931
• 负责人: James Sedinger
• 金额: $ 150.05万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-06-01 至 2001-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9985931&HistoricalAwards=false
• 关键词: Spatial; Temporal; Dynamics; Brant; Herbivore

AbstractOPP-99-85831SedingerThis project is collaborative with the University of Alaska and Colorado State University. It is being funded by the Office of Polar Programs, Division of Environmental Biology and Ecology, and Ecosystem Studies. Over the next five years, the Principal Investigators will address spatial-temporal variation in plant herbivore interactions and associated ecosystem processes in a goose grazing system in coastal tundra of the Yukon-Kuskokwim (Y-K) Delta, Alaska. Their fundamental hypothesis is that interactions between herbivores and early successional states are tightly coupled, such that herbivores require these early successional states for successful production of offspring. Furthermore, herbivores not only maintain, but are capable of creating these early successional states by grazing associated activities. Moreover, spatial/temporal complexity in vegetation patterns and the response of herbivores to habitat patches introduce substantial complexity into succession, ecosystem processes and herbivore population dynamics.The Principal Investigators will examine four inter-linked hypotheses: 1) the influence of herbivory on succession; 2) the influence of herbivory on nutrient cycling processes; 3) time lags in the successional response of vegetation to herbivory; and 4) the role that temporal-spatial patterns in herbivory play in determining ecosystem state. This proposal builds on a 16-year study of nutrition and other factors other factors on demography of the black brant (Branta bernicla nigricans) geese that nest on the coast of the Y-K Delta, and on seven years of research on vegetation/ ecosystem response to herbivory. This study takes advantage of a large sample of individually marked brant that will provide the team with an unprecedented opportunity to measure demographic responses of herbivores to the quality and quantity of their food. Intensive herbivory sophisticated experiments on the effects of herbivory on soil processes.The Principal Investigators will use a modified version of a spatial ecosystem model (SAVANNA) to test hypotheses what could not otherwise be examined about the relationship between spatial patterns of herbivory and ecosystem state. SAVANNA will be directly linked to a goose population model to fully incorporate herbivore dynamics into their hypothesis testing, and the field experiments are designed to allow them to parameterize SAVANNA for coastal tundra. Modeling will also serve to guide full integration of their field experiments and monitoring across trophic levels.The current project also will link research on the same population of geese and associated wetland habitats in Mexico. This may be the first study to fully integrate dynamics of soil processes, vegetation and herbivory in an ecosystem context at such a broad spatial scale.

摘要OPP-99-85831Sedinger该项目是与阿拉斯加大学和科罗拉多州立大学合作的。 它由极地项目办公室、环境生物学和生态学以及生态系统研究部资助。 在接下来的五年中，主要研究人员将研究阿拉斯加育空-库斯科奎姆 (Y-K) 三角洲沿海苔原鹅放牧系统中植物食草动物相互作用和相关生态系统过程的时空变化。 他们的基本假设是，食草动物和早期演替状态之间的相互作用是紧密耦合的，因此食草动物需要这些早期演替状态才能成功产生后代。 此外，食草动物不仅能够维持而且能够通过放牧相关活动来创造这些早期演替状态。 此外，植被格局的时空复杂性以及食草动物对栖息地斑块的响应给演替、生态系统过程和食草动物种群动态带来了极大的复杂性。首席研究员将研究四个相互关联的假设：1）食草动物对演替的影响； 2）草食性对养分循环过程的影响； 3）植被对食草动物的连续反应存在时间滞后； 4）草食动物的时空模式在决定生态系统状态中发挥的作用。 该提案建立在对 Y-K 三角洲沿岸筑巢的黑雁 (Branta bernicla nigricans) 人口统计学的 16 年营养和其他因素研究以及对植被/生态系统响应的 7 年研究的基础上。草食性。 这项研究利用了大量单独标记的布兰特样本，这将为团队提供前所未有的机会来测量食草动物对其食物质量和数量的人口反应。 关于食草对土壤过程影响的密集食草复杂实验。首席研究员将使用空间生态系统模型（SAVANNA）的修改版本来测试关于食草和生态系统状态之间关系的空间模式无法通过其他方式检验的假设。 SAVANNA 将直接与鹅种群模型联系起来，将食草动物动力学完全纳入他们的假设检验中，而现场实验的目的是让他们能够对沿海苔原的 SAVANNA 进行参数化。 建模还将有助于指导实地实验和跨营养级别监测的全面整合。当前的项目还将将对墨西哥同一鹅群和相关湿地栖息地的研究联系起来。这可能是第一项在如此广泛的空间尺度上将土壤过程、植被和草食动物的动态完全整合到生态系统环境中的研究。