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Phosphogenesis in Near-Surface Santa Barbara Basin Sediments

近地表圣巴巴拉盆地沉积物中的光发生作用

基本信息

批准号：
8714996
负责人：
Clare Reimers
金额：
$ 20.47万
依托单位：
University of California-San Diego Scripps Inst of Oceanography
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
1987
资助国家：
美国
起止时间：
1987-11-01 至 1991-10-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=8714996&HistoricalAwards=false
关键词：
Phosphogenesis Near Surface Santa Barbara

项目摘要

This research is focused on determining the phosphate sources, reactions and time-scales involved in the precipita- tion and aging of authigenic phosphate in sediments of Santa Barbara Basin, California. Preliminary data from the basin indicate that authigenic phosphate is precipitating from pore waters within the upper 25 cm of the sediment column. These data also suggest that high concentrations of dissolved phosphate in the uppermost centimeter are coupled to a mat of filamentous sulfur-oxidizing bacteria, Beggiatoa spp., which blankets the sediment-water interface. The field portion of the program will include 1) seasonal collections of the mat and underlying sediments for fine-scale biomass, pore water and solid phase sampling, and 2) in situ measurements of millimeter -scale gradients of pore water oxygen and pH. In the labora- tory, investigations will be conducted of the petrology, mineralogy, chemistry, and isotopic compositions of individual sediments lamina and separated phosphatic phases. These latter efforts should provide definitive data for evaluating the nature, stability, and accumulation rates of phases precursory to carbonate fluorapatite. The contribution of Beggiatoa biomass to the total diagenetic phosphate flux, as well as the influence of the chemical microenvironment of the mat on other mechanisms of phosphate regeneration, such as iron-oxyhydroxide shuttling, will also be determined. Overall, the results will contribute to our understanding of the primary processes that remove phosphorus from the ocean to the global sedimentary reservoir.

这项研究的重点是确定磷酸盐来源，反应和时间尺度参与precipita- 桑塔河沉积物中自生磷酸盐的存在与老化芭芭拉盆地，加州。盆地的初步数据表明自生磷酸盐从孔隙中沉淀出来沉积柱上部25厘米内的沃茨水域。这些数据还表明，高浓度的溶解最上面一厘米的磷酸盐与一层丝状硫氧化细菌，贝氏菌属，这覆盖沉积物-水界面。的字段部分该计划将包括1）季节性收集的垫子，底层沉积物中的细尺度生物质、孔隙水和固相取样，2）原位测量毫米 - 孔隙水氧和pH的尺度梯度。托利，将进行岩石学调查，矿物学、化学和同位素组成沉积薄层和分离的磷酸盐相。这些后者这些努力应该为评估相的性质、稳定性和积累速率到碳酸氟磷灰石。 Beggiatoa的贡献生物量占成岩磷酸盐总通量的比例，以及垫的化学微环境对其它的影响磷酸盐再生机制，如羟基氧化铁穿梭，也将确定。总的来说，结果将有助于我们理解将海洋中的磷转移到全球沉积物中水库