Evaluating the Effects of High Particulate Fluxes on Chemical Processes Occurring at the Amazon River/Ocean Boundary (Renewal)

评估高颗粒通量对亚马逊河/海洋边界发生的化学过程的影响（更新）

• 批准号: 9116298
• 负责人: David DeMaster
• 金额: $ 17.15万
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-01-01 至 1994-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9116298&HistoricalAwards=false
• 关键词: Evaluating; Effects; Particulate; Fluxes; Chemical

This proposal is a renewal for the existing grant entitled "Evaluating the Effects of High Particulate Fluxes at the Amazon River/Ocean Boundary," which is part of the AmasSeds (A Multi- Disciplinary Amazon Shelf SEDiment Study) Project. Three research cruises to the Amazon shelf (August 1989; February, 1990; May 1990; and November, 1991) have been completed successfully. This time series approach to understanding the chemical, physical, and geological processes active at the Amazon River/ocean boundary enables the investigators to resolve the variable influences of river discharge, tidal resuspension, local wind stress, and the intensity of coastal currents on particle-associated processes. The specific topics of research described in this proposal include: 1) evaluating the effects of suspended sediment concentration on the biological uptake and regeneration of nutrients and carbon; 2) the release of radium isotopes to the water column from particles and sediments and their use in tracking seabed/water column exchange processes; 3) scavenging of particle-reactive elements from continental shelf waters; 4) uranium cycling during river/ocean mixing; and 5) tracing biological and physical processes on the Amazon shelf based on the distribution of carbon and stable isotopic data. Measurements of radioactive tracers in the water column and seabed enable investigators to characterize many of these processes on a variety of time scales (ranging from days to hundreds of years). This proposal requests support for two additional years of research, which will be used to complete data analyses, work up individual data sets, model the initial results, and integrate the field measurements with the other research groups taking part in the project.

该提案是对“评估亚马逊河/海洋边界上高颗粒通量的影响”现有赠款的续签，该赠款是积累的一部分（一个多学科的亚马逊架子沉积物研究）。 三项研究到亚马逊架子（1989年8月； 1990年2月； 1990年5月； 1991年11月，1991年）。 这种时间序列的方法是理解亚马逊河/海洋边界活动的化学，物理和地质过程，使研究人员能够解决河流排放，潮汐重悬，局部风应力以及沿海电流强度对粒子相关过程的可变影响。 该提案中描述的研究的具体主题包括：1）评估悬浮沉积物浓度对养分和碳的生物学摄取和再生的影响； 2）从颗粒和沉积物中释放给水柱的镭同位素及其在跟踪海床/水柱交换过程中的使用； 3）清除大陆架水域的颗粒反应元件； 4）河流/海洋混合期间铀循环； 5）根据碳和稳定同位素数据的分布在亚马逊架子上追踪生物学和物理过程。 水柱和海床中放射性示踪剂的测量使研究人员能够在各种时间尺度上（从天到数百年）表征许多此类过程。 该提案要求支持另外两年的研究，这些研究将用于完成数据分析，进行单个数据集，对初始结果进行建模，并将现场测量结果与其他参与项目的研究小组集成在一起。