Biogeochemistry of the Amazon River: Mainstem-Flood Plain Linkages

全面了解控制亚马逊河干流生物地球化学的过程需要考虑一系列尺度。该项目主要涉及在主干和泛滥平原之间的联系的快速到中级动态控制下运行的那些过程。在一系列研究的基础上，研究小组将：1)使用额定曲线方法来确定主要采样站的材料水文。2)预测各元素的通量。3)利用陆地卫星影像确定淹没形态，计算水在漫滩上的滞留时间。4)使用布线模型为二维水动力模型提供边界条件。5)利用该模型建立了一个泥沙输移/交换模型，该模型利用野外观测数据和陆地卫星MSS图像上可见的浊度模式进行了校正。6)利用有机质的一系列同位素示踪剂确定交换的来源。7)考察DOC的潜在吸附机理。8)改进河流内呼吸速率估计。9)通过测量生物标志物的变化来确定哪类化合物可能是底物。10)使用流体动力学模型作为驱动力，评估这些化合物的总体潜力。研究团队是一支优秀的团队，有着悠久的富有成效的合作历史。受赠人机构的设施一流，巴西运营中心的住宿条件也很好。与巴西科学伙伴的关系由来已久，关系极佳。

An overall understanding of the processes controlling the biogeochemistry of the Amazon River mainstem requires consideration of a series of scales. This project addresses primarily those processes operating at the fast- to intermediate dynamic control of the linkages between the mainstem and floodplain. Based on a series of research cruises the research team will: 1) Use a rating-curve approach to define material hydrographs at the primary sampling stations. 2) Predict fluxes for the respective elements. 3) Calculate the residence time of water on the floodplain, with inundation patterns determined by Landsat imagery. 4) Use the routing model to provide boundary conditions to a two- dimensional hydrodynamic model. 5) Use this model to drive a sediment transport/exchange model, calibrated with data from field sites validated with field data and with turbidity patterns visible on Landsat MSS images. 6) Use a series of isotope tracers of organic mater to identify sources responsible for exchange. 7) Examine potential DOC adsorption mechanisms. 8) Refine the within river respiration rate estimates. 9) Identify what class of compounds may be the substrates by measuring changes in biomarkers. 10) Evaluate the overall potential of these compounds using the hydrodynamic model as a driver. The research team is an excellent one with a long history of productive collaboration. Facilities at the grantee institution are excellent, and accommodations at the Brazilian operations center. Relations with Brazilian scientific partners are long- standing and excellent.