Towards a Model of the Biogeochemistry of Continental-Scale River Basins: An Amazon Case Study

里奇研究公司建议她考虑大规模流域的动力学，并使用亚马逊铆钉系统作为测试案例。这项提案要解决的中心问题是，一个大的河流系统如何获得并随后改变其生物地球化学组成？问题和假设将分为以下几个部分：(1)地表如何影响河流系统的生物地球化学滞留？(2)在通过河流系统的运输过程中，土地效应是如何被改变的？总而言之，工作假说是：“在河流系统的任何下游节点的一小块水中，溶解和颗粒生物活性物质的数量和组成是可以预测的，作为一系列公共过程的产物，这些过程根据上游的相对排版条件、土壤有机含量和质地、水和停留时间以及泛滥平原的范围而不同地发生。”为了验证这一假设，研究目标是：(1)实施和实施现场采样计划，有效地从整个盆地提供样本，包括从主干、主要支流沿线的横断面以及秘鲁和玻利维亚的源头地区提供样本。超滤技术将被用于处理不同颗粒和分子大小的水。(2)建立基于河网输水、颗粒物和溶解物质的定量模型。这项工作将把我们以前开发的水文和化学模型与我们的新信息结合起来。(3)通过实验确定土壤对有机质组成的影响。利用模拟方法，将确定存在于细颗粒组分中的细有机物的上限，以及化学选择性。模拟吸收实验将是流域内主动分区的第三次测试。(4)通过泥沙迁移和迁移的测量和模拟，研究对颗粒物输出的控制。将使用同位素示踪剂来确定物质来源的位置。(5)

Richey Research is proposed her to consider the dynamics ogf large-scale drainage basins, using the Amazon Rivet system as a test case. The central question to be addressed in this proposal is, How does a large river system obtain and subsequently modify its biogeochemical composition? The question and hypothesis will be divided into parts: (1) How is the biogeochemical stay of the river system influenced by the land surfaces? (2) How are the land effects modified during transit through the river system? The summaty working hypothesis is that, "The quantity and composition of dissolved and particulate bioactive materials in a parcel of water at any downstreasm node in the river system is predictable as the product of a common set of processes which occur differentially according to upstream conditions of relative typography, soil organic content and texture, water and residence time, and floodplain extent." To test this hypothesis the research objectives are to: (1) Implement and carry out a field sampling program that will efficiently provide samples from throughout the basin, including from the mainstem, from transects along major tributaries, and into headwater regions of Peru and Bolivia. Ultrafiltration techniques will be used to process water across a spectrum of particle and molecular sizes. (2) Develop a quantitative model based on routing water and particulate and dissolved substances through the rivernetwork. This effort will couple the hydrology and chemistry models we have previously developed with our new information. (3) Conduct experiments to determine terrestial effects on organic matter composition. Using a modeling approach, upper bounds of fine organic material thwt exist in the fine particle fraction will be determined as will the chemical selectivity. Simulated absorption experiments will be the third test for active partioning within the drainage basin. (4) Controls on particulate export will be investigated using measurments and modeling of sediment mobil ization and routing. Isotopic tracers will be used to determine the location of material origin. (5)