Collaborative Research: Above- and Belowground Response of Coniferous Ecosystems to Tree-Fall Gaps

合作研究：针叶林生态系统对树木倒伏间隙的地上和地下响应

• 批准号: 8909038
• 负责人: Thomas Spies
• 金额: $ 19.81万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-11-01 至 1993-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8909038&HistoricalAwards=false
• 关键词: Collaborative; Research; Above; Belowground; Response

A collaborative research project will be conducted by the University of Washington, Yale University, and Oregon State University for an experimental study of ecosystem responses to tree-fall gaps and spatial and temporal relationship between above- and belowground gaps. It is hypothesized that mechanisms of community and ecosystem responses to gaps can only be understood if both above- and belowground structures and resources are considered. An experiment to determine the size of aboveground gap needed to form a belowground gap in mature and old-growth coniferous forests will be imposed. The investigators will also measure how above-and belowground structural changes are reflected in resource availability and loss and in vegetative response. To examine the hypotheses, the team will create tree- fall gaps of ranging from small to large in five sizes (0, 2, 8 and 16 and 32 trees removed) in reach of two stand developmental stages: mature (understory reinitiation), and old growth. Above and belowground sampling will be conducted to provide an estimate of the mean of the gap and will consist of root biomass (separated into tree, shrub and herb components), N leaching below the rooting zone, and soil temperature and moisture, light level determinations, shrub and herb biomass, seed germination and monitoring of advanced regeneration. In the old-growth stands, above-and belowground resources (plus net N mineralization) and vegetative biomass will be sampled more intensively to provide not only an estimate of the gap mean but of the within-gap spatial patterns. In addition, trenching experiments will be established in the old-growth stands to test the relative importance of above- and belowground resources on tree establishment and growth and develop predictive models of plant response to resources. The three-institution project team is excellent. Research sites and facilities are first rate. Results should be important to both the fundamental understanding of forest ecology and to forest resource management.

一个合作研究项目将由 华盛顿大学、耶鲁大学和俄勒冈州州立大学 生态系统反应的实验研究 林窗及其时空关系 地上和地下的空隙。 据推测， 社区和生态系统对差距的反应只能是 如果地上和地下结构以及 资源被考虑。 一个实验，以确定大小 成熟林隙需要地上林隙形成地下林隙， 古老的针叶林将被强制砍伐。 调查人员 也将测量地上和地下的结构变化 反映在资源的可利用性和损失以及植物的 反应 为了验证这些假设，该团队将创建树- 落差从小到大分为五种尺寸（0、2、8 两个林分发育区分别砍伐16株和32株 阶段：成熟（林下更新）和老生长。 上述 并进行地下取样， 的平均值的差距，并将包括根生物量 （分为乔木、灌木和草本成分），N淋失 以下生根区，土壤温度和水分，光照 水平测定，灌木和草本生物量，种子萌发 和监测高级再生。 在古老的森林里 林分、地上和地下资源（加上净N 矿化）和植物生物量将更多地取样 不仅提供差距平均值的估计， 林隙内的空间格局。 此外，挖沟 将在老林分建立试验， 地上和地下资源的相对重要性 树木的建立和生长，并建立预测模型， 植物对资源的反应 三个机构的项目团队非常出色。 研究 场地和设施都是一流的。 结果应该是重要的 对森林生态学的基本认识， 森林资源管理