CAREER: Stream Restoration, Ecological Engineering, and Nutrient Retention of Streams in Urban and Agricultural Settings

职业：河流恢复、生态工程和城市和农业环境中河流的营养物质保持--科罗拉多州立大学土木工程系Brian Bledsoe博士和ProjECT SummaryHeadwater溪流构成了大多数流域河流段长度的绝大部分，对调节大型流域的水质可能非常重要。然而，各种物理、化学和生物流属性对溶质保留的相对影响仍然不明确。这项研究的重点是当前缺乏溪流恢复的科学基础，地貌的复杂性如何与受影响和恢复的源头溪流中的营养物质保持有关，以及水资源工程课程中溪流恢复技术的生态基础的必要性。综合研究和教育计划包括：(1)对不同恢复措施影响的城市和农业环境中受影响和恢复的溪流的氮保持进行实验评估；(2)将对地貌复杂性、瞬时储存和养分保持之间联系的科学理解转化为基于过程的溪流恢复战略；(3)在拟议研究的基础上，在科罗拉多州立大学(CSU)建立生态工程专业，为本科生和研究生提供体验式和协作式的学习机会。我们计划将密集的地貌描述与基于Lotic站点间氮实验II(LINX II)协议的野外15N示踪实验相结合，以确定控制不同地貌复杂程度和背景的溪流中硝酸盐吸收和保留的速率和因素。这些实验和观察将使我们能够测试涉及人类干扰和恢复活动对河流地貌复杂性和营养物质保持的影响的各种假设，以导致LINX II数据库的扩展，以包括恢复的河流。我们将在CSU校园附近和科罗拉多州南部落基山脉的8个地貌背景下进行实验，追踪三条溪流中硝酸盐的命运：(1)城市沟道化与城市自然恢复与城市恢复(使用密集结构方法)，(2)放牧与自然恢复，以及(3)放牧与恢复(同样使用密集结构方法)。这项研究应该会加强我们对河流恢复的生态有效性的理解，并使我们能够将营养物质保持过程扩展到河流流域。教育部分将包括：(1)创建生态工程专业的本科生和研究生专业，强调跨学科、多尺度和基于过程的水生生态系统恢复方法，以及(2)与妇女和少数群体工程计划、科罗拉多州少数群体参与联盟、柯林斯堡市和其他利益攸关方合作，在CSU校园附近创建户外实验室。考察的地点(包括CSU校园内的一个新的处理湿地)将作为户外教室模型，用于研究、环境教育方法开发和短期课程。生态工程课程倡议将加强招收和留住代表不足群体的学生。

CAREER: Stream restoration, ecological engineering, and nutrient retention of streams in urban and agricultural settings - Brian Bledsoe, Ph.D., Department of Civil Engineering, Colorado State UniversityPROJECT SUMMARYHeadwater streams comprise the vast majority of stream reach length in most watersheds and could be important for regulating water quality in large basins. However, the relative influence of various physical, chemical, and biological stream attributes on solute retention remains ambiguous. This research focuses on the nexus of the current lack of a scientific basis for stream restoration, how geomorphic complexity is related to nutrient retention in impacted and restored headwater streams, and the need for an ecological underpinning for stream restoration techniques in water resources engineering curricula. The integrated research and education plan involves: (1) experimentally evaluating the nitrogen retention of impacted and restored streams in urban and agricultural settings as affected by different restoration interventions, (2) translating scientific understanding of linkages between geomorphic complexity, transient storage, and nutrient retention into process-based stream restoration strategies, and (3) establishing an Ecological Engineering concentration at Colorado State University (CSU) that builds on the foundations of the proposed research to provide experiential and collaborative learning opportunities for undergraduate and graduate students.Specifically, we plan to couple intensive geomorphic characterization with field 15N-tracer experiments based on the Lotic Intersite Nitrogen eXperiment II (LINX II) protocols to determine the rates and factors controlling nitrate uptake and retention in streams of varying geomorphic complexity and context. These experiments and observations will allow us to test a variety of hypotheses dealing with the impacts of human disturbances and restoration activities on stream geomorphic complexity and nutrient retention to result in an extension of the LINX II database to include restored streams. We will perform experiments to trace the fate of nitrate in three streams spanning 8 geomorphic contexts near the CSU campus and in the Southern Rockies of Colorado: (1) urban channelized vs. urban natural recovery vs. urban restored (using an intensive structural approach), (2) grazed vs. natural recovery, and (3) grazed vs. restored (again using an intensive structural approach). This research should enhance our understanding of the ecological effectiveness of stream restoration and allow us to scale nutrient retention processes to river basins. The educational component will include: (1) creating undergraduate and graduate concentrations in Ecological Engineering emphasizing interdisciplinary, multi-scale, and process-based approaches to aquatic ecosystem restoration, and (2) collaborating with the Women and Minorities in Engineering Program, Colorado Alliance for Minority Participation, City of Fort Collins, and other stakeholders to create outdoor laboratories proximate to the CSU campus. The sites examined (including a new treatment wetland on the CSU campus) will serve as outdoor classroom models for research, environmental education methods development, and short courses. The Ecological Engineering curriculum initiative will enhance recruitment and retention of students from underrepresented groups.