Assessing the influence of lithology on the temporal-spatial variability of sediment transport and its relation to primary production in mountain streams

评估岩性对沉积物输送时空变化的影响及其与山溪初级生产的关系

• 批准号: 1619700
• 负责人: Catalina Segura
• 金额: $ 41.19万
• 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: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2021-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1619700&HistoricalAwards=false
• 关键词: Assessing; influence; lithology; temporal; spatial

Primary production provides the fundamental source of energy for most life on earth, and therefore understanding what controls primary production is key to understanding ecosystems. In streams, relevant research has focused mainly on the influence of light and nutrients. The role of underlying geology and sediment transport has not been as well explored. The algae that dominate primary producers in headwater streams live on rocks. Flow events that mobilize those rocks can scrape algae away and reset the system to low production levels. Understanding controls on the frequency of sediment scour and abrasion in a stream is therefore fundamental to understanding the dynamics of primary production. This research project will contribute to a better understanding of the coevolution of ecosystems and landscapes.This interdisciplinary research project links fluvial geomorphology and stream ecology. The goal is to determine: (a) how spatial variability in velocity and shear stress affect sediment transport in gravel-bedded streams, (b) how these affect primary productivity at reach and patch scale, and (c) what control underlying bedrock lithology exerts on these processes. This project will couple the use of a 2D model and the collection of field measurements in four sites in the Oregon Coast Range. The sites have been selected based on similar climate, light, nutrients, and temperature, but different lithology to isolate the controls it exerts. The project is led by an early career Hispanic female investigator. Collaboration with a local high school will provide a research experience for teachers and involve Native American high school students.

初级生产为地球上大多数生命提供了基本的能源，因此了解控制初级生产的因素是了解生态系统的关键。在溪流中，相关研究主要集中在光和营养物质的影响上。底层地质和沉积物迁移的作用尚未得到很好的探索。在源头溪流中占主导地位的初级生产者的藻类生活在岩石上。移动这些岩石的流动事件可以刮走藻类并将系统重置为低生产水平。因此，了解河流中沉积物冲刷和磨损频率的控制对于了解初级生产的动态至关重要。该研究项目将有助于更好地理解生态系统和景观的共同进化。这个跨学科研究项目将河流地貌学和溪流生态学联系起来。目标是确定：（a）速度和剪切应力的空间变化如何影响砾石层溪流中的沉积物输送，（b）这些如何影响河段和斑块尺度的初级生产力，以及（c）底层基岩岩性对这些过程的控制作用。该项目将结合二维模型的使用和俄勒冈海岸山脉四个地点的现场测量数据收集。这些地点的选择基于相似的气候、光照、营养物质和温度，但岩性不同，以隔离其施加的控制。该项目由一位早期职业西班牙裔女调查员领导。与当地高中的合作将为教师提供研究经验，并让美国原住民高中生参与其中。

项目成果

Spatial Variability in Light Yields Colimitation of Primary Production by Both Light and Nutrients in a Forested Stream Ecosystem

森林溪流生态系统中光产量的空间变异对光和养分初级生产的限制

• DOI: 10.1007/s10021-016-0024-9
• 发表时间: 2017
• 期刊: Ecosystems
• 影响因子: 3.7
• 作者: Warren, Dana R.;Collins, Sarah M.;Purvis, Emily M.;Kaylor, Matthew J.;Bechtold, Heather A.
• 通讯作者: Bechtold, Heather A.