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

智力优势：陆地生态系统中溶解有机碳（DOC）的起源、功能和归宿及其从景观到海洋的迁移过程目前还不完全清楚。在这项拟议的研究中，统计和基于GIS的传输模型被用来研究DOC在陆地生态系统和河流的动态。研究目标有三个方面：1）分析亚流域尺度下陆地表面对河流DOC贡献的空间变异性。2)为了确定运输和转换机制背后的长期（几十年）和短期（几天到几个月）的DOC波动，由于自然和人为的影响。3)利用遥感反射率、浊度和叶绿素预测河流DOC浓度。在过去的几年中，大量的现场数据，包括5年的每月DOC测量的30个子流域，高时空分辨率的河流观测，和遥感图像，已收集。有了这些数据，该团队将主要依靠一种集成统计建模和基于GIS的交通建模的方法。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每月DOC负荷。2)构建基于GIS的传输模型，用于在排水网络中路由DOC质量。3)应用变系数线性函数模型和非参数函数模型对DOC进行遥感预测。4）用两个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DOC输出过程的理解，这些过程受到人类活动、自然事件、流域特征和气候之间相互作用的影响。统计贡献在于创新的估计和推理程序，特别适合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沃茨的碳输出过程的科学认识。这个项目的资金将可能改变公众？人们对其行为对沿海社区影响的看法。这项研究将导致一个建模技术，适合研究流域特性，人类活动，自然事件和气候变化之间的相互作用。该项目为所有参与的学生提供学习机会。本研究的方法，模型和数据将被整合到广泛学科（统计，地球化学，遥感，水文和建模）的本科和研究生教学计划中。该合作通过两个不同的研究机构的平等合作关系为学生提供了接触尖端建模技术和环境科学的机会。特别是，这两名女PI将是指导女研究生成为未来科学家（统计学家和地球科学家）的宝贵财富。沿海碳研究相关的教学材料将通过现有的教育计划和桥梁网站开发和传播。这些推广工作将大大受益于COSEE-New England和Watershed-Integrated Sciences Partnership（GK-12）计划的早期经验。

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.