LTREB: Moose Population Cycles, Ecosystem Properties, and Landscape Patterns on Isle Royale

LTREB：皇家岛上的驼鹿种群周期、生态系统特性和景观格局

• 批准号: 9806313
• 负责人: John Pastor
• 金额: $ 30万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-15 至 2004-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9806313&HistoricalAwards=false
• 关键词: LTREB; Moose; Population; Cycles; Ecosystem

9806313 Pastor The difficulties in developing a general theory of herbivore-ecosystem interactions arise from the long time-scales of population cycles, the complex spatial scaling of interactions between animal and plant populations, and thenon-linear effect of herbivores on carbon and nutrient flows between vegetation and soil. Such theoretical difficulties are compounded by the paucity of long-term, landscape-scale studies. This LTREB research will continue to address these problems by examining the spatial distribution of browse consumption by moose (Alces alces) in relation to browse supply, tree diameter distributions, conifer basal area, and soil nitrogen availability in the boreal forests of two valleys on Isle Royale. A series of alternative hypotheses will be tested: One series of hypotheses states that spatial patterns do not determine ecosystem recovery from the prior period of high moose population densities, while the alternative series of hypotheses invoke a central role of the dynamics of spatial patterns in ecosystem recovery. Changes in mean values of each ecosystem property will be tested by examining trends at grid points through time. This long-term research program covers a period of time in which the system has experienced the both the largest and smallest moose population densities. These extremes in population dynamics will provide valuable information on the effects of herbivores on large-scale plant community dynamics and ecosystem processes.

发展草食动物-生态系统相互作用的一般理论的困难来自于种群周期的长时间尺度，动物和植物种群之间相互作用的复杂空间尺度，以及草食动物对植被和土壤之间碳和养分流动的非线性影响。这种理论上的困难由于缺乏长期的、大规模的研究而变得更加复杂。这LTREB研究将继续解决这些问题，通过研究驼鹿（Alces alces）的浏览消费的空间分布，浏览供应，树木直径分布，针叶树断面积，和土壤氮的可用性在北方森林的两个山谷皇家岛。一系列的替代假设将进行测试：一系列的假设指出，空间格局不确定生态系统恢复从前期的高驼鹿人口密度，而替代系列的假设调用的核心作用的动态空间格局在生态系统恢复。将通过检查各网格点随时间推移的趋势来检验每一生态系统财产平均值的变化。这项长期研究计划涵盖了一段时间，在这段时间里，该系统经历了最大和最小的驼鹿人口密度。这些极端的人口动态将提供有价值的信息草食动物对大规模的植物群落动态和生态系统过程的影响。