LTREB Renewal: Trajectory for the Recovery of Stream Ecosystem Structure and Function during Reforestation

在河岸地区重新造林被广泛认为是恢复和改善美国各地溪流和河流的水和栖息地质量的最佳管理做法。每年，州、联邦和私人机构和机构在河岸森林恢复方面投入数百万美元。然而，关于河流生态系统的物理、化学和生物方面需要多长时间才能恢复，以便生态系统再次提供人类所需的服务(即，它是可游泳、可钓鱼、可饮用的)，人们知之甚少。关于溪流生态系统在恢复过程中所经历的阶段以及溪流在每个阶段的相对功能也知之甚少。该项目将记录河流生态系统恢复的各个阶段的时间框架，描述这些变化随时间的顺序，并揭示河流生态系统结构(物理、化学、生物)的恢复轨迹是否与生态系统功能(向人类提供服务)的恢复轨迹平行。这些信息反过来将有助于为更好地管理河岸走廊提供技术基础，以便人类和野生动物的淡水数量和质量能够为子孙后代维持在较高的水平。然而，河流生态系统恢复到河岸森林恢复的科学充其量是薄弱的。该项目从河流生态系统的物理结构、能量流动、营养循环以及在草地或牧场重新种植本地落叶树木后生物群落的组成等方面对河流生态系统恢复的轨迹进行了量化。随着人工林的生长和成熟，研究将集中在河流生态系统变量相对于参考--成熟的森林和草甸河流河段的端点--变化的时间框架上。该项目是跨学科的，汇集了河流地貌、水文学、生物地球化学、有机和同位素地球化学、营养循环以及异养和自养微生物、大型无脊椎动物和鱼类的群落生态学研究，以描述河流在森林河岸成熟时的变化轨迹。主要研究问题包括：不同的生物物理变量，如光、温度、河道地貌、床的复杂性和水下带交换等随时间的变化和变化顺序，以记录有机碳作为有机投入在重新造林期间的食物网处理的效率和大小，以及碳和氮处理规模等生态系统服务水平与河流生态系统恢复程度之间的关系。该项目包括若干创新办法，包括大型木屑清查和命运追踪、地下水交换研究、激光雷达地球/植被调查、微生物群落的分子指纹分析、大型无脊椎动物群落结构的物种水平分析、鱼类生物量和生产力措施，以及食物和功能性喂养动物群体的稳定同位素分析。斯特劳德研究人员正在进行的基于公民的科学家、市政雇员和农民的积极推广活动将允许公众参与，使用部署在WCC LTREB的低成本、开源传感器来测量水质参数。

Reforestation of riparian areas is widely considered a best management practice for restoring and improving water and habitat quality of streams and rivers throughout the United States. Millions of dollars are invested in riparian forest restoration each year by state, federal, and private agencies and institutions. However, little is known about how long it takes for the physical, chemical, and biological aspects of a stream ecosystem to be restored so that the ecosystem can once again provide the services that humans need (i.e. it is swimmable, fishable, drinkable). Nor is there much known about the stages that the stream ecosystem passes through during that restoration process and the stream?s relative functionality at each stage. This project will document the time frames of various stages of stream ecosystem restoration, characterize the sequence of those changes through time, and reveal whether the trajectory of recovery of stream ecosystem structure (physical, chemical, biological) parallels that of ecosystem function (delivery of service to humans). This information, in turn, will help provide the technical basis for better managing riparian corridors so that both the quantity and quality of fresh water for both humans and wildlife can be sustained at a high level for future generations.The negative effects of eliminating riparian forest along stream ecosystems are well documented. Yet, the science of stream ecosystem recovery to riparian forest restoration is weak at best. This project quantifies the trajectory of stream ecosystem recovery in terms of its physical structure, flow of energy, cycling of nutrients, and the composition of biological communities following reforestation of meadows or pastures with native deciduous trees. As the planted forest grows and matures, research will focus on the time frames over which stream ecosystem variables change compared to reference- endpoints of a mature forested- and meadow stream reach. The project is interdisciplinary, and brings together research in fluvial geomorphology, hydrology, biogeochemistry, organic and isotope geochemistry, nutrient cycling, and community ecology of heterotrophic and autotrophic microorganisms, macroinvertebrates, and fishes to describe the trajectory of stream change as a forested riparian matures. Key research questions include: the change over time and order of change of different biophysical variables, such as light, temperature, channel geomorphology, bed complexity and hyporheic zone exchange, to documenting the efficiency and magnitude of food-web processing of organic Carbon as organic inputs change during reforestation and the relationship between the level of ecosystem services such as Carbon and Nitrogen processing scale and the degree of stream ecosystem restoration. The project includes several innovative approaches including large wood debris inventories and fate-tracking, hyporheic exchange studies, LIDAR earth/vegetation surveys, molecular fingerprint analysis of microbial communities, species level analysis of macroinvertebrate community structure, fish biomass and productivity measures, and stable isotope analysis of food and functional feeding animal groups. Ongoing and active outreach citizen based scientists, municipal employees and farmers by Stroud researchers will allow public participation using low cost, open source sensors deployed in the WCC LTREB for water quality parameters.