School of Earth and Environmental Sciences, Queens College, City University of New York, Flushing, New York, United States of America; Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York, United States of America.
School of Earth and Environmental Sciences, Queens College, City University of New York, Flushing, New York, United States of America.
PLoS One. 2015 Jan 30;10(1):e0117812. doi: 10.1371/journal.pone.0117812. eCollection 2015.
In addition to efforts aimed at reducing anthropogenic production of greenhouse gases, geological storage of CO2 is being explored as a strategy to reduce atmospheric greenhouse gas emission and mitigate climate change. Previous studies of the deep subsurface in North America have not fully considered the potential negative effects of CO2 leakage into shallow drinking water aquifers, especially from a microbiological perspective. A test well in the Newark Rift Basin was utilized in two field experiments to investigate patterns of microbial succession following injection of CO2-saturated water into an isolated aquifer interval, simulating a CO2 leakage scenario. A decrease in pH following injection of CO2 saturated aquifer water was accompanied by mobilization of trace elements (e.g. Fe and Mn), and increased bacterial cell concentrations in the recovered water. 16S ribosomal RNA gene sequence libraries from samples collected before and after the test well injection were compared to link variability in geochemistry to changes in aquifer microbiology. Significant changes in microbial composition, compared to background conditions, were found following the test well injections, including a decrease in Proteobacteria, and an increased presence of Firmicutes, Verrucomicrobia and microbial taxa often noted to be associated with iron and sulfate reduction. The concurrence of increased microbial cell concentrations and rapid microbial community succession indicate significant changes in aquifer microbial communities immediately following the experimental CO2 leakage event. Samples collected one year post-injection were similar in cell number to the original background condition and community composition, although not identical, began to revert toward the pre-injection condition, indicating microbial resilience following a leakage disturbance. This study provides a first glimpse into the in situ successional response of microbial communities to CO2 leakage after subsurface injection in the Newark Basin and the potential microbiological impact of CO2 leakage on drinking water resources.
除了努力减少人为温室气体的产生外，地质封存二氧化碳也被探索作为一种减少大气温室气体排放和减缓气候变化的策略。先前对北美的深部地下环境的研究并未充分考虑二氧化碳泄漏到浅层饮用水含水层的潜在负面影响，特别是从微生物学的角度来看。纽瓦克裂谷盆地的一口测试井在两项野外实验中得到了利用，以研究在将二氧化碳饱和水注入隔离含水层段（模拟二氧化碳泄漏情景）后微生物演替的模式。注入二氧化碳饱和含水层水后 pH 值下降，同时痕量元素（如铁和锰）被迁移，回收水中的细菌细胞浓度增加。在测试井注入前后采集的样本中进行 16S 核糖体 RNA 基因序列文库比较，将地球化学变化与含水层微生物学变化联系起来。与背景条件相比，测试井注入后微生物组成发生了显著变化，包括变形菌门数量减少，厚壁菌门、疣微菌门和通常与铁和硫酸盐还原有关的微生物类群增加。与背景条件相比，微生物细胞浓度的增加和微生物群落的快速演替表明，在实验性二氧化碳泄漏事件后，含水层微生物群落发生了显著变化。注入后一年采集的样本在细胞数量上与原始背景条件相似，群落组成虽然不完全相同，但开始向注入前的条件恢复，表明在泄漏干扰后微生物具有恢复能力。本研究首次揭示了在纽瓦克盆地地下注入后微生物群落对二氧化碳泄漏的原位演替响应，以及二氧化碳泄漏对饮用水资源的潜在微生物影响。
