The geochemical ecology of cryptoendolithic microorganisms: relationships between cyanobacteria and sandstone weathering in the Canadian High Arctic

提供资金调查蓝藻和藻类参与产生超碱性条件，导致快速岩石风化和溶解的硅水泥和矿物在加拿大高北极地区的程度。初步结果表明，一个潜在的大规模机制，生物化学风化，并提出了新的问题，生化机制和微生物-矿物相互作用。拟议的项目将阐明微生物介导的风化机制在隐石栖息地的光养微生物，以及这些微生物群落控制景观演变的程度。主要研究者将回答五个问题：1。蓝藻占主导地位的栖息地中微生物群落的性质是什么？2.蓝藻能在多大程度上改变隐石生境的孔隙水pH值？3.蓝藻如何改变孔隙水的pH值，在什么样的表面条件下？4.碱性条件会加速砂岩的化学风化吗？5.溶解的二氧化硅的命运是什么？他将使用现场和实验室的工具和技术，通过他在微生物学，分子生物学，地质学和地球化学的研究来表征cryptocentolithic栖息地和相关的微生物群落，确定蓝藻和藻类的生物碱化机制，并记录在这个高北极环境中由光养微生物产生的高pH值对岩石风化的影响。

Funds are provided to investigate the degree to which cyanobacteria and algae are involved in generating hyperalkaline conditions that result in rapid rock weathering and dissolution of silica cements and minerals in the Canadian High Arctic. Preliminary results suggest a potentially large-scale mechanism for biogenic chemical weathering, and raise new questions about biochemical mechanisms and microbe-mineral interactions. The proposed project will elucidate microbially-mediated weathering mechanisms in cryptoendolithic habitats by phototrophic microorganisms, and the degree to which these microbial communities control landscape evolution. The Principal Investigator will address five questions: 1. What is the nature of the microbial community in cyanobacterial-dominated habitats?2. To what extent can cyanobacteria alter the pore water pH of cryptoendolithic habitats?3. How do cyanobacteria alter pore water pH, and under what surface conditions?4. Do alkaline conditions lead to accelerated chemical weathering of sandstone rocks?5. What is the fate of the dissolved silica?He will use both field and laboratory tools and techniques developed through his research in microbiology, molecular biology, geology and geochemistry to characterize the cryptoendolithic habitat and associated microbial communities, identify mechanisms for bioalkalization in cyanobacteria and algae, and document the impact of high pH generated by phototrophic microorganisms on rock weathering in this High Arctic environment.