Microbial geochemistry dynamics

细菌被广泛认为是原始和受污染的水环境中一系列地球化学反应的主角。细菌作为地球化学反应的“促进剂”的行为，不仅是因为它们无处不在的分布和多样化的代谢能力，而且还源于它们固有的细胞表面反应能力和吸收广泛溶解的化学物质的能力。我们最近的许多工作都是关于极端环境(例如，安第斯山脉、加拿大北极高地的温泉)，但并不排除有助于定义这些极端环境的更“正常”的生态系统(例如，地下水泉水)。我们的研究还被用来量化微生物作为溶解成矿元素的吸着剂和矿物沉淀的成核底物的地球化学行为。迫在眉睫的关切是探索用于可持续自然修复印度地下水供应的饮用水系统中氟(F-)的细菌矿物沉淀反应(在印度，致残性氟中毒是地方病)，以及评估深层地下和酸性矿山排水环境中原核生物病毒(即噬菌体)的多样性，以及它们通过吸附和矿物沉淀反应防止金属污染物在水系统中迁移的潜力。此外，研究还将侧重于开发微生物Fe2+/Fe3+在涉及硅酸盐矿物的沉淀-溶解反应中的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消除二氧化碳的耦合过程方面。这一举措标志着微生物地球化学向前迈出了开创性的一步，进入了一个具有挑战性的新研究领域，重点是破译自然界中微生物和地球化学过程之间存在的复杂的时空关系，并了解与环境变化相关的干扰的迫在眉睫的后果。

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.