Photolysis and Photoproduction of Acrylate in Seawater and their Impact on the Marine Organosulfur Cycle

海水中丙烯酸酯的光解和光生成及其对海洋有机硫循环的影响

基本信息

批准号：
1756907
负责人：
David Kieber
金额：
$ 46.34万
依托单位：
SUNY College of Environmental Science and Forestry
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-02-01 至 2023-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1756907&HistoricalAwards=false
关键词：
Photolysis Photoproduction Acrylate Seawater their

项目摘要

This project would investigate the marine chemistry of the compound acrylate. Acrylate is a mostly overlooked by-product of a very well-studied process through which a compound known as DMSP (dimethylsulfoniopropionate), a compound produced by phytoplankton, is converted to the gas dimethylsulfide (known as DMS). This process is an important part of understanding the marine cycling of sulfur, and DMS plays a role in cloud formation and climate. Thus, these aspects of the conversion of DMSP to DMS have received considerable attention. On the other hand, very little is known about acrylate concentrations, fluxes, or impacts in the oceans, even though it is produced during the conversion of DMSP to DMS. Acrylate concentrations and fluxes should at times be substantial, especially in shallow-water coral reefs or during blooms of DMSP-rich phytoplankton that are common throughout the world's oceans and often harmful or toxic. It is likely that acrylate is a reactive form of marine organic matter that significantly impacts the carbon cycle and ecology of the upper ocean. This project will foster research and educational opportunities for undergraduates and one graduate student through several avenues including field work with international collaborators, attendance at national and local meetings, mentoring, preparing for and delivering college-level lectures, and presentations made to the general public at forums such as Syracuse's Milton J. Rubenstein Museum of Science. Results will be disseminated through peer-reviewed publications, media communications, web-based data bases, and presentations at scientific meetings, public forums and in the classroom. A three-year project is proposed to study the effect of sunlight on the formation and loss of acrylate in seawater, to model these processes in the water column, and to determine if photoproduction and photolysis are important pathways in the marine acrylate cycle in a shallow-water coral reef. Four objectives are planned to carry out this research: (1) synthesize radiocarbon-labeled DMSP as a source of radiocarbon-labeled acrylate for photolysis and uptake studies; (2) conduct laboratory experiments using a solar simulator to study the photolysis and photoproduction of acrylate in water and seawater under varying conditions (e.g., pH, temperature, oxygen concentration); (3) determine temperature and wavelength-dependent quantum yields for acrylate photolysis and acrylate photoproduction in seawater using a monochromatic irradiation system; and (4) conduct a field study at the Richard Gump Research Station to determine rates of photolysis, photoproduction and microbial consumption of acrylate in a shallow-water coral reef.

该项目将研究化合物丙烯酸酯的海洋化学。丙烯酸酯是一个经过充分研究的过程的大多数被忽略的副产品，通过该副产品被称为DMSP（Dimethylsulfoniopionate），该化合物是由浮游植物产生的化合物，它被转换为气体二甲基硫化物（称为DMS）。这个过程是理解硫的海洋自行车的重要组成部分，而DMS在云形成和气候中起着作用。因此，DMSP转换为DMS的这些方面受到了很大的关注。另一方面，即使在DMSP转换为DMS期间产生的丙烯酸酯浓度，通量或冲击，丙烯酸酯的浓度，通量或影响很少。丙烯酸酯的浓度和通量有时应该很大，尤其是在浅水珊瑚礁中，或者在富含DMSP的浮游植物的盛开期间，这些浮游植物在世界的海洋中很常见，并且通常有害或有毒。丙烯酸酯可能是海洋有机物的一种反应性形式，它显着影响上海的碳循环和生态学。该项目将通过几种途径，包括与国际合作者的实地合作，参加国家和地方会议，指导，为大学级别的讲座做准备，并向锡拉丘兹的米尔顿·J·鲁布恩斯坦（Milton J. Rubenstein）等论坛上的普通出版物进行演讲，从而为大学生和一名研究生提供研究和教育机会。结果将通过经过同行评审的出版物，媒体通信，基于Web的数据库以及在科学会议，公共论坛和课堂上的演示进行传播。提出了一个为期三年的项目，以研究阳光对海水中丙烯酸酯形成和丧失的影响，以对水柱中的这些过程进行建模，并确定在浅水珊瑚礁中的丙烯酸酯丙烯酸酯循环中的光增生性和光解会是重要的途径。计划进行四个目标以进行这项研究：（1）将放射性碳标记的DMSP合成为放射性碳标记的丙烯酸酯的来源，用于光解和摄取研究；（2）使用太阳能模拟器进行实验室实验，以研究在不同条件下（例如，pH，温度，氧浓度）在水和海水中丙烯酸酯的光解和光生促生殖器；（3）使用单色辐照系统确定海水中丙烯酸酯光解和丙烯酸酯光生源的温度依赖性量子产率；（4）在理查德·阿甘研究站进行了一项现场研究，以确定光解，光生物生产和微生物消耗丙烯酸酯在浅水珊瑚礁中的消耗。