Stable Nitrogen Isotope Ratios as a Tracer of Bacterial Nitrogen Sources in Estuarine and Coastal Waters

稳定氮同位素比作为河口和沿海水域细菌氮源的示踪剂

• 批准号: 9017443
• 负责人: Luis Cifuentes
• 金额: $ 13.66万
• 依托单位: Texas A&M Research Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-02-01 至 1993-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9017443&HistoricalAwards=false
• 关键词: Stable; Nitrogen; Isotope; Ratios; Tracer

Newly developed nucleic acid probes will be used to study nitrogen cycling between dissolved substrate pools and bacteriain estuarine, coastal and open ocean waters. It is anticipatedthat the implementation of these techniques will provide and approach to examine the relative importance of bacterial nitrogen sources where multiple sources with varying nutritional values are available. The focus of this research will be: 1) to complete the adaptation of a nucleic acid isolation/isotope measurement technique, which was used to trace bacterial carbon sources in estuarine waters, to one that will trace bacterial nitrogen sources in eutrophic and oligotrophic waters, 2) to continue development and field testing of a method to measure stable nitrogen isotopes in dissolved organic matter, and 3) to compare the isotopic discrimination between bacteria (isolated as nucleic acids) and nitrogen sources in eutrophic and oligotrophic waters. Field work will be conducted on a transect from the Trinity River, Texas to the mouth of Galveston Bay out additional stations along the standard transect from Galveston Bay out to the 2000 m isobath in the Gulf of Mexico.

新开发的核酸探针将用于研究河口、沿海和开阔海域中溶解的底物池和细菌之间的氮循环。预计这些技术的实施将提供一种方法来检查细菌氮源的相对重要性，其中有多种不同营养价值的来源可用。这项研究的重点将是：1)完成将用于示踪河口水域细菌碳源的核酸分离/同位素测量技术改编为将用于追踪富营养化和贫营养水域细菌氮源的核酸分离/同位素测量技术；2)继续开发和现场测试溶解有机物中稳定氮同位素的方法，3)比较富营养化和低营养化水体中细菌(以核酸形式分离)和氮源之间的同位素识别。将在从德克萨斯州三一河到加尔维斯顿湾入海口的样带上进行实地工作，并沿着从加尔维斯顿湾到墨西哥湾2000米等深线的标准样带增加站点。