期刊
WATER RESEARCH
卷 223, 期 -, 页码 -出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.watres.2022.118971
关键词
Interfacial photochemistry; Photochemically produced reactive; intermediates (PPRIs); Hydroxyl radical; Soil-water interface; Biogeochemical processes; Wetland
资金
- National Natural Science Foundation of China (NSFC) [22136004, 42107392, 22006129]
The wetland soil-water interface (SWI) is found to be an important hotspot for the production of photochemically produced reactive intermediates (PPRIs), which play a critical role in accelerating biogeochemical cycles on earth surface. The enhanced PPRI productions at the SWI are caused by intensified photon absorption and vibrant Fe-mediated redox processes. Nationwide wetland investigations demonstrate that the SWI is a ubiquitous hotspot for PPRI productions. Simulations suggest that the enhanced PPRI productions greatly affect the kinetics and transformation pathways of nutrients and pollutants.
Photochemically produced reactive intermediates (PPRIs) formed by sunlight-irradiation of natural photosensitizers play critical roles in accelerating biogeochemical cycles on earth surface. Existing PPRI studies mostly focus on bulk phase reactions (e.g., bulk water), with PPRI processes at the environmental interfaces largely unexplored. Here, we report the wetland soil-water interface (SWI) as a widespread but previously unappreciated hotspot for PPRI productions. Massive productions of four important PPRI species (i.e., triplet-state excited organic matter ((OM)-O-3*), singlet oxygen (O-1(2)), hydrogen peroxide (H2O2), and hydroxyl radical ((OH)-O-center dot)) were observed at the SWI. All four PPRI species exhibited higher productions at the SWI than those in bulk water, where (OH)-O-center dot production was largely elevated by up to one order of magnitude. The enhanced PPRI productions at the SWI were caused by intensified photon absorption and vibrant Fe-mediated redox processes, where the light absorption by less-or non-photoactive soil substances partially offset the enhancement on PPRI productions. Nationwide wetland investigations demonstrate that the SWI was a ubiquitous hotspot for PPRI productions. Simulations on PPRIs-mediated reactions suggest that the enhanced PPRI productions could greatly affect the kinetics and transformation pathways of nutrients and pollutants. Given that the SWI also acts a hotspot for nutrient and pollutant accumulation, incorporating the SWI enhanced PPRI productions into biogeochemical process assessments is pivotal for advancing our understandings on the element cycles and pollutant dynamics in wetlands.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据