Environmental controls on microbialite and microbial mat biomineralization in Saskatchewan

矿物生物特征和微生物群落：矿物生物特征是具有由生物体独特产生的结构的沉积物或岩石。当在岩石记录中被识别时，矿物生物特征提供了历史微生物生命的记录;例如，生锈矿物的螺旋线是富含铁的沃茨中细菌活动的证据。地质学家利用这些信息来帮助了解地球上古代环境和生命的历史。萨斯喀彻温省的草原景观拥有一系列独特的环境，微生物在其中产生矿物生物特征，包括矿泉和沼泽中的铁和硫微生物垫。在草原盐湖中，微生物可以加速生物矿物的形成并积累在微生物岩（层状丘状结构）中。这些生物系统在萨斯喀彻温省的大陆性气候中经历了剧烈的季节性极端温度和干旱。与全球气候变化相伴随的气候条件变化会产生额外的压力，这些变化对矿物生物特征的影响尚未记录。目的：这项研究计划的目的是确定如何改变气候参数（例如，温度、盐度）对微生物岩和微生物垫中微生物群落的影响，以及这如何影响矿物生物特征的形成、蚀变、形态和地球化学。 科学方法：这项研究将整合一套多学科的现场和实验室研究方法。我们将使用分子微生物学技术来研究多样性，分布和季节性微生物的变化，在我们的现场和微生物从这些环境将被培养和表征。光学和电子显微镜以及基于同步加速器的分析工具将用于检查生物特征的矿物结构、形态和化学。基于实验室的模型系统将模拟这些生物特征形成的环境，并测试不断变化的条件对生物特征形成的影响。影响力：研究萨斯喀彻温省现代生物特征环境的地质微生物学将产生原创性研究，有助于了解全球和地质历史中这些系统中的微生物-矿物相互作用，以及与工业相关的应用。这项研究将阐明季节变化，气候变化和矿物生物特征形成和改变之间的关系，这将提高我们识别和解释岩石记录中以及火星等地外环境中生物特征的能力。我们分离的微生物将具有作为研究模式生物的价值，并在水处理应用中（例如，从地下水中除去铁或硫）。更广泛的科学影响包括对气候参数变化如何影响其他环境中类似的微生物-矿物质相互作用的新见解（例如，在钢铁基础设施的腐蚀中，在矿山废物中，以及在沉积物和土壤中）。

Mineral biosignatures and microbial communities: Mineral biosignatures are sediments or rocks with structures uniquely produced by living organisms. When identified in the rock record, mineral biosignatures provide a record of historical microbial life; for example, helical threads of rusty minerals are evidence of bacterial activity in iron-rich waters. Geologists use this information to help understand the history of ancient environments and life on Earth. Saskatchewan's prairie landscape hosts a range of unique environments where microbes produce mineral biosignatures, including iron and sulfur microbial mats in mineral springs and marshes. In prairie saline lakes, microbes can accelerate biomineral formation and accumulate in microbialites (layered mound structures). These biological systems experience dramatic seasonal extremes of temperature and aridity in Saskatchewan's continental climate. Changing climate conditions concomitant with global climate change contribute additional stresses and affects of these changes on mineral biosignatures has not yet been documented. Objective: The objective of this research program is to determine how changing climate parameters (e.g., temperature, salinity) affect microbial communities in microbialites and microbial mats, and how this influences mineral biosignature formation, alteration, morphology, and geochemistry. Scientific approach: This research will integrate a multidisciplinary suite of field and laboratory research methods. We will use molecular microbiological techniques to study diversity, distribution, and seasonal microbiological variations at our field sites and microbes from these environments will be cultured and characterized. Light and electron microscopy and synchrotron-based analytical tools will be used to examine the mineral structures, morphology, and chemistry of the biosignatures. Lab-based model systems will simulate environments where these biosignatures form and test the influence of changing conditions on biosignature formation. Impact: Examining the geomicrobiology of modern biosignature environments in Saskatchewan will produce original research with implications for understanding microbe-mineral interactions in these systems globally and in geological history, as well as in industry-relevant applications. This research will illuminate relationships between seasonal changes, climate change, and mineral biosignature formation and alteration that will improve our ability to recognize and interpret biosignatures in the rock record, and in extraterrestrial environments such as Mars. The microbes we isolate will have value as model organisms for research, and in water treatment applications (e.g., removal of iron or sulfur from groundwater). Broader scientific impacts include new insight on how changing climate parameters influence similar microbe-mineral interactions in other settings (e.g., in corrosion of steel infrastructure, in mine wastes, and in sediments and soils).