CNH: Collaborative Research: Northern Gulf of Mexico Hypoxia and Land Use in the Watershed: Feedback and Scale Interactions

每年，墨西哥湾北部都会形成一个缺氧(缺氧)区，对沿海和海洋渔业以及当地经济造成不利影响。该地带的空间范围约为国家缺氧行动计划目标目标的三倍。对这些缺氧状况的原因和后果的科学评估表明，来自密西西比河上游和俄亥俄河流域河流系统的氮和磷负荷对该区域的大小和持续时间都有重要贡献。土地利用，主要来自农业，是这些养分负荷的关键驱动因素，是这些河流流域50多万名个体生产者做出的决定的结果。然而，仅了解生物地球化学过程不足以理解这一复杂系统的动力学。该项目通过开发综合的、数据丰富的模型，捕捉与不同情景下从个人到分水岭的影响扩大相关的空间和时间非线性，以全新的方式审视这个巨大系统的自然和人类动态。这项研究将产生第一个完整的建模系统，跟踪上密西西比州、俄亥俄州和田纳西州盆地在田间范围内通过环境和水文组件做出的农业土地使用决定，以及下游水质的影响，包括墨西哥湾缺氧区的大小。独一无二的是，建模工作将包括通过市场的反馈，以及通过适应性管理形式的公共政策的反馈。这个项目将演示如何使用进化算法的强大工具来整合人类和自然过程模型。对于美国其他地方和许多其他国家的沿海栖息地来说，缺氧是一个日益严重的环境问题。根据这项研究建立的一般模型框架将为设计和执行政策提供有效工具，以解决墨西哥湾的缺氧和水质问题，并确定在景观中以具有成本效益的方式进行保护的做法。该项目将加强五个不同机构的科学家之间的跨学科合作，并将支持研究生和本科生的培训。

Each year an oxygen-depleted (hypoxia) zone forms in the Northern Gulf of Mexico, negatively impacting coast and marine fisheries and local economies. The spatial extent of this zone is about three times the target goal of the national Hypoxia Action Plan. The scientific assessment of causes and consequences of these hypoxic conditions indicates that both nitrogen and phosphorous loadings from the Upper Mississippi River Basin and Ohio River Basin stream systems are significant contributors to the size and duration of the zone. Land use, primarily from agriculture, is a key driver of these nutrient loadings and is the result of decisions made by more than 500,000 individual producers in those river basins. However, understanding the biogeochemical processes alone is insufficient to understanding the dynamics of this complex system. This project takes a fresh look at the natural and human dynamics of this enormous system by developing integrated and data-rich models that capture the spatial and temporal non-linearity associated with scaling up the impacts from individuals to the watershed under different scenarios. The research will produce the first complete modeling system that traces agricultural land-use decisions, made at the field scale in the Upper Mississippi, Ohio, and Tennessee Basins through both environmental and hydrologic components, to downstream water quality effects, including the size of the hypoxic zone in the Gulf of Mexico. Uniquely, the modeling effort will incorporate feedbacks via the market, and feedbacks via public policy in the form of adaptive management. This project will demonstrate how to integrate human and natural process models using the powerful tools of evolutionary algorithms. Hypoxia is a growing environmental problem for coastal habitats elsewhere in the United States and many other countries. The development of a general modeling framework from this research will provide an effective tool for the design and implementation of policy to address both Gulf hypoxia and water quality concerns, and identify cost-effective placement of conservation practices within the landscape. This project will strengthen an interdisciplinary collaboration among scientists at five different institutions, and will support the training of graduate and undergraduate students.