Microbial geochemistry dynamics

细菌被广泛认为是原始和污染的水环境中的一系列地球化学反应的主角。 细菌作为地球化学反应性“代理商”的行为不仅是由于它们无处不在的分布和不同的代谢能力，而且还源于它们固有的细胞表面反应性和吸附各种溶解化学物质的能力。 我们最近的大部分工作都是在极端环境下进行的（例如，安第斯山脉的温泉，加拿大高北极），但不排除更“正常”的生态系统（例如，地下水泉），帮助定义这些极端。我们的研究也被用来量化的地球化学行为的微生物作为吸附剂溶解的矿物形成元素，并作为矿物沉淀的成核基质。 当前关注的是探索细菌性矿物沉淀反应，用于印度地下水供应的饮用水系统中氟化物（F-）的可持续自然修复（在那里，致残性疾病氟中毒是地方病），以及评估原核病毒的多样性（即，噬菌体）在深层地下和酸性矿井排水环境中的作用，以及它们通过吸附和矿物沉淀反应防止金属污染物在含水系统中迁移的潜力。 研究还将侧重于开发涉及硅酸盐矿物的沉淀溶解反应中微生物Fe 2 +/Fe 3+氧化还原循环的动态定量地理空间模型，特别是在有助于从大气中去除CO2的耦合过程方面。 这一举措是微生物地球化学向前迈出的开创性一步，成为一个具有挑战性的新研究领域，重点是破译自然界微生物和地球化学过程之间存在的复杂时空关系，并了解与环境变化相关的干扰即将发生的后果。

Bacteria are widely recognized as protagonists of a range of geochemical reactions in pristine and contaminated aqueous environments. The behavior of bacteria as geochemically reactive "agents provocateurs" is engendered not only by their ubiquitous distribution and diverse metabolic capabilities, but also stems from their intrinsic cell-surface reactivity and ability to sorb a wide range of dissolved chemicals. Much of our recent work has been on extreme environments (e.g., hot springs in the Andes, the Canadian High Arctic), but not to the exclusion of more "normal" ecosystems (e.g., groundwater springs) that help to define these extremes. Our studies have also been used to quantify the geochemical behavior of microorganisms as sorbents for dissolved mineral-forming elements, and as nucleation substrates for mineral precipitation. Of immediate concern is exploration of bacteriogenic mineral precipitation reactions for sustainable natural remediation of fluoride (F-) in groundwater-supplied drinking water systems in India (where the crippling disease fluorosis is endemic), as well as assessment of the diversity of prokaryotic viruses (i.e., bacteriophage) in the deep subsurface and acid mine drainage environments, and their potential to prevent metal contaminant migration in aqueous systems through sorption and mineral precipitation reactions. Studies will focus additionally on development of dynamic quantitative geospatial models for microbial Fe2+/Fe3+ redox cycling in precipitation-dissolution reactions involving silicate minerals, particularly in terms of coupled processes that contribute to the removal of CO2 from the atmosphere. This initiative represents a groundbreaking step forward for microbial geochemistry into a challenging new area of research focused on deciphering the complex spatial and temporal relationships that exist between microbial and geochemical processes in nature, and understanding impending consequences of disturbances associated with environmental change.