Sources and controls of greenhouse gases and heavy metals in mine water: A continuing climate legacy.
Sources and controls of greenhouse gases and heavy metals in mine water: A continuing climate legacy.
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DOI：
10.1016/j.scitotenv.2023.167371
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发表时间：
2023-09
期刊：
影响因子：
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通讯作者：
Alison M. Brown;A. Bass;Mark H Garnett;U. Skiba;John M. Macdonald;Amy E. Pickard
中科院分区：
文献类型：
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作者：
Alison M. Brown;A. Bass;Mark H Garnett;U. Skiba;John M. Macdonald;Amy E. Pickard
废弃煤矿产生的水污染是仅次于污水的淡水污染源，在煤田集水区，矿井水可能是主要污染物，氧化铁使接收河流的河床窒息。这项研究测量了苏格兰米德兰山谷16个地点的矿井水流出物中的温室气体。利用放射性同位素和稳定碳同位素（Δ 14 C和δ 13 C）测定了矿井水淹环境中甲烷（CH 4）和二氧化碳（CO2）的来源。甲烷4-C的浓度范围为20至215 μg l− 1，二氧化碳2-C的浓度范围为30至120 mg l− 1，二氧化碳占矿井水全球变暖潜力的97%。甲烷的成因包括51%的现代生物成因、41%的热成因和8%的煤的氢营养甲烷化。最显着的生物源甲烷浓度的反向影响是硫酸盐，最有可能是由于硫酸盐还原细菌竞争产甲烷菌。二氧化碳的来源包括64%来自石灰岩的溶解，21%来自陆地有机碳和15%来自煤。石灰石中的CO2与高浓度硫酸盐成正相关，高浓度硫酸盐导致硫酸的生成，并导致碳酸盐从石灰石中溶解。矿井沃茨经历了显著的碳酸盐缓冲，仅变为微酸性（pH 6-7），但无机碳显著损失。矿井沃茨的溶解氧浓度低（6-25%），溶解铁浓度高（2 - 65 mg l-1），锰浓度高（0.5 - 5 mg l-1）。来自废弃矿井的溶解温室气体估计为苏格兰全球变暖潜力的0.27+ 0.31 - 0.18%。这项新的工作提供了有关矿井沃茨中温室气体通量的来源和控制的信息，并确定了量化和报告这一排放量的必要性。
Water pollution arising from abandoned coal mines, is second only to sewage as a source of freshwater pollution and in coalfield catchments mine water can be the dominant pollutant, with oxidised iron smothering the bed of receiving rivers. This study measured greenhouse gases in mine water outflows from sixteen sites across the Midland Valley in Scotland. Radiogenic and stable carbon isotopes measurements (Δ 14 C and δ 13 C) were used to determine the sources of both methane (CH 4) and carbon dioxide (CO 2) produced within the flooded mine environment. Concentrations of CH 4-C ranged from 20 to 215 μg l− 1 and CO 2-C from 30 to 120 mg l− 1, with CO 2 accounting for 97% of the mine water global warming potential. Methane origins included 51% modern biogenic, 41% thermogenic and 8% from hydrogenotrophic methanogenesis of coal. The most significant inverse impact on biogenic CH 4 concentrations was sulphate, most likely due to sulphate reducing bacteria outcompeting methanogens. Carbon dioxide origins included 64% from the dissolution of limestone, 21% from terrestrial organic carbon and 15% from coal. The limestone derived CO 2 was positively correlated with high sulphate concentrations, which resulted in sulphuric acid and caused the dissolution of carbonate from limestone. The mine waters experienced significant carbonate buffering becoming only slightly acidic (pH 6–7), but with significant loss of inorganic carbon. The mine waters had low dissolved oxygen (6–25%) and high dissolved iron (2 to 65 mg l− 1) and manganese (0.5 to 5 mg l− 1) concentrations. Dissolved greenhouse gases from abandoned mines were estimated as 0.27+ 0.31− 0.18% of Scotland's global warming potential. This novel work has contributed information about the sources and controls of greenhouse gas fluxes in mine waters and identified the need to quantify and report this emissions term.