Collaborative Research: Modeling DOC dynamics from landscapes to coasts: hydrological connectivity and estuary processes

知识价值：陆地生态系统中溶解有机碳（DOC）的起源、功能和命运及其从景观到海洋的运输过程仅部分被了解。在本研究中，采用统计模型和基于gis的运输模型研究陆地生态系统和河流的DOC动态。研究目标有三个方面：1)分析地表对流域DOC贡献的空间变异性。2)确定自然和人为影响下长期（几十年）和短期（日至月）DOC波动背后的运输和转化机制。3)利用遥感反射率、浊度和叶绿素预测河流中DOC浓度。在过去的几年里，我们收集了大量的野外数据，包括30个子流域5年的月度DOC测量数据、高时空分辨率河流观测数据和遥感影像。有了这些数据，研究小组将主要依靠一种将统计建模和基于gis的运输建模相结合的方法。具体而言，他们将1)使用自适应变系数混合模型从统一的土地利用类型中获得月度DOC负荷。2)构建基于gis的水系网DOC块体路径传输模型。3)利用变系数函数线性模型和非参数函数模型对DOC进行遥感预测。4)用两个特定河流流域的独立数据集对上述模型进行验证。该项目的地球科学贡献在于提高了对受人类活动、自然事件、流域特征和气候相互作用影响的DOC输出过程的理解。统计贡献在于创新的估计和推理程序，特别适合于这种复杂的地球科学数据。更广泛的影响：这项拟议的研究将提高对从陆地到沿海水域的碳出口过程的科学理解。资助这个项目是否会潜在地改变公众？美国人对他们的行为对沿海社区的影响的看法。该研究将产生一种适合于研究流域特性、人类活动、自然事件和气候变化之间相互作用的建模技术。该项目为所有参与的学生提供了学习机会。本研究的方法、模型和数据将被整合到广泛学科（统计学、生物地球化学、遥感、水文学和建模）的本科和研究生教学计划中。通过两个不同的研究机构的平等伙伴关系，该合作为学生提供了最前沿的建模技术和环境科学的机会。特别是，两位女pi将成为指导女研究生成为具有自己经验的未来科学家（统计学家和地球科学家）的宝贵资产。沿海碳研究相关的教学材料将通过现有的教育项目和桥梁网站开发和传播。这些外联工作将极大地受益于cosee -新英格兰和流域综合科学伙伴关系（GK-12）项目的早期经验。

Intellectual Merit: The origin, function, and fate of dissolved organic carbon (DOC) in terrestrial ecosystems and its transport processes from landscapes to sea are only partially understood. In this proposed research, statistical and GIS-based transport models are used to study DOC dynamics in terrestrial ecosystems and rivers. The research objectives are three-fold: 1) To analyze the spatial variability of DOC contributions from land surfaces to streams at sub-basin scales. 2) To identify the transport and transformation mechanisms behind long (decades) and short (days to months) term DOC fluctuations due to natural and anthropogenic influences. 3) To predict DOC concentration from remote sensing reflectance, turbidity and chlorophyll in rivers. In the past several years, a large amount of field data, has been collected including 5-years of monthly DOC measurements in 30 sub-basins, high spatial and temporal resolution riverine observations, and remote sensing imagery. Equipped with these data, the team will rely mainly on an approach that integrates statistical modeling and GIS-based transport modeling. Specifically, they will 1) Use an adaptive varying coefficient mixture model to derive monthly DOC loads from uniform land use types. 2) Construct a GIS-based transport model for routing DOC mass in the drainage stream network. 3) Use a varying coefficient functional linear model and nonparametric functional model to predict DOC through remote sensing 4) Validate the above models with independent data sets from two specific river watersheds. The geosciences contribution from this project lies in the improved understanding of the DOC export processes influenced by interactions among human activities, natural events, watershed characteristics, and climate. The statistical contribution lies in the innovative estimation and inference procedures that are particularly adapted to this complex geoscience data. Broader impacts: This proposed research will improve the scientific understanding of carbon export processes from land to coastal waters. Funding of this project will potentially change the public?s perception of the influence of their actions in coastal communities. This research will result in a modeling technique that is suitable for studying interactions among watershed properties, human activities, natural events and climate change. The project provides learning opportunities for all participating students. The methods, models, and data from this research will be integrated into undergraduate and graduate teaching programs in a broad range of disciplines (statistics, biogeochemistry, remote sensing, hydrology, and modeling). The collaboration offers students access to cutting edge modeling techniques and environmental sciences through an equal partnership of two diverse research institutions. Especially, the two female PIs will be valuable assets in guiding female graduate students to become future fellow scientists (statisticians and geo-scientists) with their own experiences. Coastal carbon research-related instructional materials will be developed and disseminated through existing educational programs and The Bridge website. These outreach efforts will strongly benefit from early experience on the COSEE-New England and Watershed-Integrated Sciences Partnership (GK-12) programs.