Mechanisms of Calcium Carbonate Precipitation and Dissolution: Microbial Populations, Metabolic Processes and Mineral Products

碳酸钙沉淀和溶解的机制：微生物种群、代谢过程和矿物产品

• 批准号: 0311929
• 负责人: Pieter Visscher
• 金额: $ 33.21万
• 依托单位: University of Connecticut
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2007-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0311929&HistoricalAwards=false
• 关键词: Mechanisms; Calcium; Carbonate; Precipitation; Dissolution

Visscher Abstract This project is investigating the underlying mechanisms of carbonate precipitation in biologically active sediments by performing a geobiological study on a gradient from lithifying to non-lithifying microbial communities from microbial mats in a hypersaline pond (Eleuthera, Bahamas). Field measurements and in situ manipulations are being combined with a variety of laboratory experiments to isolate and characterize the biological processes and environmental variables that control carbonate precipitation. The PIs are examining microbial community composition, metabolic rates, and EPS characteristics in relation to carbonate mineral formation. Environmental parameters which are being investigated include water chemistry (e.g., pH, [Ca2+], [CO32-]) and light intensity. Microbial metabolism (production/consumption of inorganic carbon) on carbonate precipitation are being investigated by experimenting with pure and mixed bacterial cultures in both batch and continuous culture. By focusing on precipitation and dissolution along a natural gradient from lithifying mats to gelatinous EPS-rich mats, the PIs hope to understand the general rules that govern calcium carbonate precipitation by microbial communities. This information is being used to develop a mechanistic theory describing mineral precipitation in biologically active sediments. Since the main microbial guilds (cyanobacteria, sulfur oxidizers, sulfate reducers) responsible for carbonate precipitation are found in numerous environments, the theory developed will address the entire carbonate factory, the role of microbes in the formation of geologically important mineral products and the lithification and preservation of biological materials.

Visscher摘要本项目通过对高盐池塘（巴哈马伊柳塞拉）微生物垫中从石化到非石化微生物群落的梯度进行地球生物学研究，调查生物活性沉积物中碳酸盐沉淀的潜在机制。 实地测量和现场操作正在与各种实验室实验相结合，以分离和描述控制碳酸盐沉淀的生物过程和环境变量。 PI正在检查微生物群落组成、代谢率和与碳酸盐矿物形成有关的EPS特征。 正在研究的环境参数包括水化学（例如，pH、[Ca ~（2+）]、[CO ~（32-）]）和光照强度。 微生物代谢（无机碳的生产/消耗）对碳酸盐沉淀的影响正在研究中，实验与纯和混合细菌培养物在分批和连续培养。 通过关注沉淀和溶解，沿着一个自然梯度，从石化垫，凝胶EPS丰富的垫，PI希望了解的一般规则，管理碳酸钙沉淀的微生物群落。 这一信息正被用于发展一种描述生物活性沉积物中矿物沉淀的机理理论。 由于在许多环境中发现了负责碳酸盐沉淀的主要微生物工会（蓝细菌，硫氧化剂，硫酸盐还原剂），因此开发的理论将解决整个碳酸盐工厂，微生物在地质上重要的矿产品形成中的作用以及生物材料的石化和保存。