蓝绿菌诱导碳酸盐矿物形成机制研究

项目名称： 蓝绿菌诱导碳酸盐矿物形成机制研究

项目编号： No.41302079

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 天文学、地球科学

项目作者： 闫华晓

作者单位： 山东科技大学

项目金额： 23万元

中文摘要： 目前国内外微生物岩研究主要集中在微生物组成及其构造类型上，对微生物诱导的碳酸盐矿物形成机制和沉积过程有待深入分析。本项目以蓝绿菌集胞藻Synechocystis sp. PCC6803细胞为实验材料研究其诱导碳酸钙沉积机制。LCSM观察不同Ca2+浓度培养的集胞藻细胞壁Ca2+浓度变化情况，分析外界钙离子对集胞藻钙化的影响；HRTEM、HAADF及EDS观察不同Ca2+浓度不同pH下活体和死体细胞钙化的发生部位及胞内纳米晶体的存在情况，分析胞内胞外碳酸钙的颗粒大小和晶态的不同；AFM观察集胞藻环境中碳酸钙的生长过程，分析集胞藻生物因素对碳酸钙沉积物的影响；SEM观察碳酸钙表面形貌，FTIR、EPMA、XRD、TGA和DSC确定矿物元素组成和晶态特征，分析集胞藻诱导的碳酸钙与对照（未接种集胞藻）碳酸钙的差异及其成因。通过以上研究以期探讨微生物诱导碳酸钙沉积的机制。

中文关键词： 蓝绿菌；碳酸盐；沉积机制；镁钙比；热稳定性

英文摘要： Researches on microbialite mainly focused on the biological compositions and structure types at home and abroad until now, and the carbonate mineral formation mechanism and sedimentary process induced by microorganisms need to be further studied. In this program, cyanobacteria Synechocystis sp. PCC6803 cells are studied as the experimental materials to study the calcium carbonate sedimentation mechanism. Extracellular Ca2+ concentrations will be measured by AAS method. SEM, LCSM will be used to analyze Ca2+ distributions within cell walls. HRTEM, HAADF and EDS will be used to analyze structure differences of mineral particles formed in cells cultured with different pH values and Ca2+ concentrations. Growth mechanism of mineral crystals will be studied at the microscopic level by AFM. SEM will be used to morphological analysis of mineral surfaces, meanwhile FTIR, EPMA and XRD will be used to analyze elements and structures of crystals. The mineral will be investigated by TGA and DSC methods to analyze the impact rules of Synechocystis biological factors on calcium carbonate sediments. Based on the above researches,the sedimentation mechanism of microbial carbonate induced by cyanobacteria is expected to be further elucidated.

英文关键词： cyanobacteria；carbonate；deposition mechanism；Mg/Ca ratio；thermostability