酸性矿山废水对岩溶河水中溶解性有机质光化学和生物降解的影响
Effects of acid mine drainage on photochemical and biological degradation of dissolved organic matter in karst river water
Linwei Li, Xingxing Cao, Chujie Bu, Pan Wu*, Biao Tian, Yongheng Dai, Yeye Ren
https://doi.org/10.1016/j.jes.2022.12.012
摘要
溶解性有机质（Dissovled organic matter, DOM）可通过光化学和生物过程，将有机碳转化为无机碳而得以去除或转化，这在岩溶碳循环中起着至关重要的作用。而酸性矿山废水（Acid mine drainage, AMD）会影响这一过程。因此，研究AMD影响下岩溶河水中DOM的降解有重要意义。为此，本研究将AMD和岩溶河水以不同的比例混合，并分别在仅可见光照射、仅生物降解、仅紫外光照射和紫外光照射+生物降解等条件下进行受控培养实验，以期揭示不同环境条件下AMD影响的岩溶河水DOM含量及其光学特征参数的动态变化。研究表明，AMD中的DOM荧光成分主要由内源性成分衍生的类蛋白质物质组成，而岩溶河水中的DOM荧光成分主要是具有内源性和外源性来源的类腐殖质物质。而在紫外光照射+生物降解条件下AMD和岩溶河水混合后，样品中平均DOC浓度显著降低了23%，这比在其他条件下高出1.2-1.4倍，表明该环境条件下易于将DOM转化成无机碳。因此，AMD强化岩溶河水中DOM的降解，该过程影响岩溶碳汇的稳定性。本研究从碳循环的角度探讨了 AMD 对流域水环境的影响，强调了加强 AMD 治理的迫切性，尤其是在与全球碳循环密切相关的岩溶地区。
亮点
揭示了酸性矿山废水对岩溶河水中溶解性有机质的降解作用。
紫外光照射+生物降解条件下AMD污染的岩溶河水中DOC浓度显著降低。
酸性矿山废水未经处理直接排放影响岩溶碳汇的稳定性。
Abstract
Dissolved organic matter (DOM) can be removed or transformed by photochemical and biological processes, producing the negative effect of transforming organic carbon into inorganic carbon, which plays a vital role in the karst carbon cycle. However, acid mine drainage (AMD) will affect this process, so the degradation of DOM in karst river water (KRW) needs to be studied in this context. In this study, to reveal the evolution processes of DOM under photochemical and biological conditions in AMD-impacted KRW, AMD and KRW were mixed in different ratios under conditions of visible light irradiation (VL), biodegradation (BD), ultraviolet irradiation (UV) and ultraviolet irradiation + biodegradation (UV+BD). The average DOC concentrations in samples after mixing AMD and KRW in different proportions decreased significantly (by 23%) in UV+BD, which was 1.2–1.4 times higher than under the other conditions and would lead to a significant release of inorganic carbon. Further analysis of the fluorescence parameters via parallel factor analysis (PARAFAC) revealed that the DOM fluorescence components in AMD comprised mainly protein-like substances derived from autochthonous components, while the DOM fluorescence components in KRW were mainly humic-like substances with both autochthonous and allochthonous sources. Therefore, AMD could promote both the photochemical and biological degradation of DOM in karst receiving streams, resulting in the conversion of DOC to inorganic carbon. The results showed that the synergistic effects of UV+BD and AMD accelerated the degradation of DOM and the release of inorganic carbon in KRW, thus affecting the stability of the karst carbon cycle.
作者简介
李林蔚，贵州大学资源与环境工程学院环境工程专业硕士研究生，主要研究方向为溶解性有机质的地球化学行为与环境效应。以第一作者在Journal of Environmental Sciences、Science of the Total Environment 等国际期刊发表论文2篇。
吴攀，贵州大学二级教授，博导。国务院政府特殊津贴专家、贵州省管专家、贵州省优秀青年科技人才、贵州省高层次创新型人才（“十”层次）、NSFC-贵州喀斯特科学中心重大项目负责人。长期从事岩溶地质环境演化、矿山环境污染过程与控制、水/土环境重金属污染与治理修复等方面的研发工作。主持了国家重点研发计划课题、国家自然科学基金项目以及贵州省重大科技成果转化项目等30余项。在国内外重要学术刊物上发表论文300余篇（其中第一或通讯作者136篇，SCI论文140篇），出版学术专著3部，参编团体标准2项。获授权发明专利14件（包括美国发明专利2件），软著1件。获环境保护科学技术奖、绿色矿山突出贡献奖、省级科技进步奖和教学成果奖等6项。
原文链接
https://www.sciencedirect.com/science/article/pii/S1001074222006271
引用格式
Linwei Li, Xingxing Cao, Chujie Bu, Pan Wu, Biao Tian, Yongheng Dai, Yeye Ren, 2024. Effects of acid mine drainage on photochemical and biological degradation of dissolved organic matter in karst river water. J. Environ. Sci. 135, 26-38.
