Collaborative Research: Leaky Rivers: Nutrient Retention and Productivity in Rocky Mountain Streams Under Alternative Stable States

合作研究：渗漏河流：替代稳定状态下落基山脉溪流的养分保留和生产力

• 批准号: 1146283
• 负责人: Robert Hall
• 金额: $ 32.32万
• 依托单位: University of Wyoming
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1146283&HistoricalAwards=false
• 关键词: Collaborative; Research; Leaky; Rivers; Nutrient

Streams occupy a small part of Earth's surface, but are disproportionately important for transport and processing of nutrients and for maintaining global biodiversity. Logjams in streams increase retention of nutrients and fish production. Human removal of logjams is pervasive in forested ecosystems, creating "dam-impoverished" streams with limited capacity to store nutrients and produce fish. A prime example is streams of the southern Rocky Mountains, where a legacy of wood removal has greatly reduced logjams. This project asks: Does the loss of jams reduce the productive capacity of headwater streams? It is hypothesized that the loss of jams makes streams more leaky of nutrients, with subsequent decreased nutrient processing and fish production. This project will examine logjams and jam-associated processes across a gradient of streams, including streams in old-growth forests, unmanaged younger forests, and intensively managed forests. This work will provide the first landscape-scale assessment of the effects of jam removal on stream ecosystems. This research can transform current understanding of wood effects on stream ecosystems by combining estimates of logjam historical distribution with intensively measured geochemical and biological variables in contemporary jams, allowing extension of local-scale observations to entire steam networks. Understanding how the loss of jams affects streams will inform resource management of headwater streams in forested landscapes. The National Park Service and the US Forest Service oversee vast tracts of forested lands in the American West and are attempting to restore some of the inferred historical characteristics of the Rocky Mountain landscape. By enhancing understanding of changes in jams, as well as the biogeochemical and ecological influence of these structures, the proposed work will provide much-needed context for these management actions. This project will also provide training for one post-doctoral scholar and four graduate students. It will also provide research experiences for several undergraduate students.

溪流占据了地球表面的一小部分，但对于养分的运输和处理以及维持全球生物多样性的运输和处理非常重要。流中的logjams增加了营养和鱼类生产的保留率。在森林生态系统中，人类对logjams的去除是普遍存在的，创造了“大坝破裂”的溪流，其储存营养和生产鱼的能力有限。一个主要的例子是南部落基山脉的溪流，那里的木材遗产大大减少了logjams。该项目要求：果酱的损失是否会降低源水流的生产能力？假设果酱的损失使养分的流动更加漏水，随后养分加工和鱼类生产减少。该项目将检查各个溪流的logjams和与果酱相关的过程，包括旧生长森林中的溪流，不受管理的年轻森林和强化管理的森林。 这项工作将对果酱去除对流生态系统的影响进行首次景观规模评估。这项研究可以通过将logjam历史分布的估计与当代果酱中的地球化学和生物变量相结合，从而改变人们对木材生态系统的现有理解，从而可以将局部规模的观察扩展到整个蒸汽网络。了解果酱的损失如何影响溪流将为森林景观中的源头流的资源管理提供信息。国家公园管理局和美国森林服务局监督了美国西部的大量森林土地，并试图恢复落基山山景的一些推论历史特征。通过增强对果酱变化以及这些结构的生物地球化学和生态影响的理解，拟议的工作将为这些管理行为提供急需的背景。 该项目还将为一名博士后学者和四名研究生提供培训。它还将为几位本科生提供研究经验。