BE/CNH: Feedbacks Between Complex Ecological and Social Models: Urban Landscape Structure, Nitrogen Flux, Vegetation Management, and Adoption of Design Scenarios

切萨皮克湾是美国最大的河口，根据《清洁水法》被列为“受损沃茨”。 该海湾遭受溶解氧，淹没水生植被，鳍鱼和贝类渔业的下降。 来自邻近土地的氮负荷是造成这种损害的关键原因。 州和联邦机构已经同意在2011年之前将进入海湾的氮负荷减少40%。 在减少点源氮负荷方面取得了很大进展，特别是农业和污水处理厂，现在注意力正转向海湾流域的非点源氮。 在区域的基础上，城市和郊区的土地贡献了最多的营养海湾。 释放到海湾的氮量是水文，生物，化学和社会因素之间相互作用的产物，因此是理解耦合自然-人类生态系统复杂性的优秀集成器。 这个跨学科的研究项目的目标是调查景观结构之间的联系，从城市流域的氮通量，以及通过植被管理改变景观的社会和物理能力。 将研究连接这些因素的反馈回路。 城市设计，满足社区的喜好，但也旨在减少氮负荷将被调查作为一种工具，以关闭反馈回路。 研究人员将模拟新的建筑和景观设计如何改变景观结构，从而影响城市和郊区流域的氮输出。 他们将与管理人员合作，确定植被管理方案，以最大限度地减少土地的氮损失，他们将把这些方案纳入新的城市设计。 将评估对比社区采用预期设计的能力的物理和社会限制。 这些设计被证明是可被真实的社区所采用的，将被纳入改变的大都市景观模型中，以预测未来景观结构和相关管理的能力，以防止氮流入海湾。 首先，它将采用和测试一种适合复杂城市地区的新的综合土地覆盖分类。 其次，它将扩展生物复杂性理论，包括生态，水文和社会系统与城市设计实践的联系。 第三，该项目将测试目前通过改变城市土地覆盖减少非点氮负荷的管理战略。 此外，社区、中小学、大学生、研究生和博士后将通过就业、暑期学生实习和教师奖学金、教师讲习班、课后和暑期课程以及课程材料的开发从该项目中受益。 这些活动将把研究与代表性不足的人口联系起来，并将促进“职业阶梯”，使这些群体的成员接触环境科学专业。 对联邦、州和地方政府管理人员、非营利组织和社区团体的宣传将侧重于植被管理和设计方案。 该项目的结果将对公民团体、环境资源管理者和大都市规划者有用。 对比模型的可视化将帮助社区和规划者评估经济发展、社区振兴和生态恢复的情景。 该项目得到了2005财政年度环境中生物复杂性特别竞赛的支持，该竞赛侧重于自然和人类系统耦合的动力学。

The Chesapeake Bay, the largest estuary in the U.S., is classified as "impaired waters" under the Clean Water Act. The bay suffers from declines in dissolved oxygen, submersed aquatic vegetation, and finfish and shellfish fisheries. Nitrogen loading from adjacent lands is a key cause of this impairment. State and federal agencies have agreed to reduce nitrogen loading into the Bay by 40 percent before 2011. Much progress has been made in mitigating nitrogen loading from point sources, particularly agriculture and sewage treatment plants, and attention is now turning to non-point sources of nitrogen in the bay's watershed. On an area basis, urban and suburban lands contribute the most nutrients to the bay. The amount of nitrogen released to the bay is a product of interactions between hydrology, biology, chemistry, and social factors and therefore is an excellent integrator for understanding complexity in coupled natural-human ecosystems. The goal of this interdisciplinary research project is to investigate the links among landscape structure, nitrogen flux from urban watersheds, and the social and physical capacity to alter the landscape through vegetation management. A feedback loop linking these factors will be investigated. Urban designs that satisfy community preferences but also are aimed at reducing nitrogen loading will be investigated as a tool to close the feedback loop. The investigators will model how new architectural and landscape architectural designs alter landscape structure and therefore influence nitrogen export from urban and suburbanizing watersheds. They will work with managers to identify vegetation management options thought to minimize nitrogen loss from the land, and they will incorporate those options into new urban designs. The physical and social constraints on the ability of contrasting neighborhoods to adopt the prospective designs will be evaluated. The designs that prove to be adoptable by real communities will be included in models of altered metropolitan landscapes to predict the capacity of future landscape structure and associated management to prevent nitrogen flow to the bay.This project will have important implications. First, it will employ and test a new integrated land-cover classification appropriate to complex, urban regions. Second, it will expand biocomplexity theory to include connections of ecological, hydrological, and social systems with the practice of urban design. Third, the project will test the current management strategy of reducing non-point nitrogen loading by modifying urban land cover. In addition, communities, primary and secondary schools, college students, graduate students, and post-docs will benefit from the project through employment, summer student internships and teacher fellowships, teacher workshops, after-school and summer programs, and development of curricular materials. These activities will link the research with under-represented populations and will promote a "career ladder" to expose members of these groups to environmental science professions. Outreach to federal, state, and local government managers, non-profit organizations, and community groups will focus on vegetation management and design options. The results of the project will be useful to citizen groups, environmental resource managers, and metropolitan planners. Visualizations of the contrasting models will help communities and planners evaluate scenarios for economic development, community revitalization, and ecological restoration. This project is supported by an award resulting from the FY 2005 special competition in Biocomplexity in the Environment focusing on the Dynamics of Coupled Natural and Human Systems.