| 2 | 0 | 10 |
| 下载次数 | 被引频次 | 阅读次数 |
为阐明藻源有机质(Algae-derived organic matter, AOM)在铁/锰氧化物上的吸附分馏行为，本研究以浒苔提取的AOM为代表，探究δ-MnO2、针铁矿、赤铁矿在不同有机质浓度和pH条件下对AOM中不同组分的吸附特征以及吸附前后介质中有机质光谱特征的变化情况。研究表明，pH=8.0时不同的铁/锰氧化物对AOM的吸附特征存在一定差异：δ-MnO2表现出最大的吸附容量且选择性分馏高芳香性、低腐殖化程度的大分子组分；针铁矿表现出最强的结合强度，且吸附容量高于赤铁矿。两种铁氧化物均选择性分馏高芳香性、低腐殖化程度组分，不同在于针铁矿分馏分子量不同的组分不受浓度影响，始终分馏低分子量组分，而赤铁矿随浓度升高由低分子量组分分馏转向大分子量组分。通过对比两种pH条件下分馏特征，发现铁氧化物(针铁矿与赤铁矿)分馏特征受pH影响显著，pH=8.0时优先吸附小分子组分而pH=6.5时则转变为大分子组分吸附为主，其与AOM结合机制主要为pH敏感的静电作用与配体交换作用；而δ-MnO2与AOM作用除部分氧化还原作用外结合机制主要为疏水作用、范德华力等pH不敏感的机制，其整体分馏趋势一致，但pH改变会影响其分馏特征转化的浓度范围。本研究为深入理解铁/锰氧化物与AOM的吸附分馏机制提供了理论依据，对于揭示富营养化水体有机质的迁移转化与生态风险预估具有重要的应用价值。
Abstract：To elucidate the sorption fractionation behavior of algae-derived organic matter(AOM) on iron-manganese oxides, this study used AOM extracted from Ulva prolifera as a representative to investigate the sorption characteristics of different AOM components on δ-MnO2, goethite, and hematite under varying organic matter concentrations and pH conditions, as well as the changes in spectral characteristics of organic matter in the medium before and after sorption. The results indicated significant differences in the sorption characteristics of AOM on different iron-manganese oxides at pH=8.0: δ-MnO2 exhibited the highest sorption capacity and selectively fractionated macromolecular components with high aromaticity and low humification degree. Goethite showed the strongest binding affinity and a higher sorption capacity than hematite. Both iron oxides preferentially fractionated components with high aromaticity and low humification degree; however, they differed in the molecular weight(MW) of the fractionated components. Goethite consistently fractionated low-MW components regardless of concentration, whereas hematite shifted from fractionating low-MW to high-MW components as the concentration increased. By comparing the fractionation characteristics at two pH levels, it was found that the fractionation behavior on iron oxides(goethite and hematite) was significantly influenced by pH, with their primary binding mechanisms being pH-sensitive electrostatic interactions and ligand exchange. In contrast, the fractionation on δ-MnO2 was largely unaffected by pH. Besides partial redox reactions, its interaction with AOM was governed mainly by pH-insensitive mechanisms such as hydrophobic interactions and van der Waals forces. This study provides a theoretical basis for understanding the sorption fractionation mechanisms between iron-manganese oxides and AOM, offering valuable insights for revealing the transport, transformation, and ecological risk assessment of organic matter in eutrophic waters.
[1] 吴元强，金伟，化柯，等.典型藻型湖湾中溶解有机质及其生物可降解性的时空变化[J].环境科学，2025,46(3):1406-1416.Wu Y Q,Jin W,Hua K,et al.Spatial and temporal variation of dissolved organic matter and its biodegradability in typical Algal Bay[J].Environmental Science,2025,46(3):1406-1416.
[2] Xiang R,Tian Z B,Zhang C D,et al.Characterization of dissolved organic matter content,composition,and source during spring algal bloom in tributaries of the Three Gorges Reservoir [J].Science of The Total Environment,2023,879:163139.
[3] Suo C Y,Zhao W S,Liu S S,et al.Molecular-level insight into the origin-dependent adsorption fractionation of dissolved organic matter on ferrihydrite in aquatic environment:Implications for carbon sink in eutrophic lakes [J].Chemical Engineering Journal,2024,494:152960.
[4] Elizabeth K C,Tsutomu O,and Alain F P.Adsorption and molecular fractionation of dissolved organic matter on iron-bearing mineral matrices of varying crystallinity[J].Environmental Science & Technology,2018,52(3):1036-1044.
[5] Ding Z C,Ding Y,Yang J J,et al.Coupled sorption and oxidation of soil dissolved organic matter on manganese oxides:Nano/sub-nanoscale distribution and molecular transformation[J].Environmental Science & Technology,2022,56(4):2783-2793.
[6] Lv J T,Zhang S Z,Wang S S,et al.Molecular-Scale investigation with esi-ft-icr-ms on fractionation of dissolved organic matter induced by adsorption on iron oxyhydroxides[J].Environmental Science & Technology,2016,50(5):2328-2336.
[7] Lv J T,Miao Y X,Huang Z Q,et al.Facet-Mediated adsorption and molecular fractionation of humic substances on hematite surfaces[J].Environmental Science & Technology,2018,52(20):11660-11669.
[8] Ohno T,Sleighter R L,and Hatcher P G.Adsorptive fractionation of corn,wheat,and soybean crop residue derived water-extractable organic matter on iron (oxy)hydroxide[J].Geoderma,2018,326:156-163.
[9] 林德菊，王楠，李浩帅，等.海洋沉积物中铁保护的有机碳埋藏研究进展[J].海洋科学，2023,47(6):108-123.Lin D J,Wang N,Li H S,et al.Preservation of sedimentary organic carbon protected by iron:A review[J].Marine Sciences,2023,47(6):108-123.
[10] Schwertmann U,Cornell R M.Iron Oxides in the Laboratory:Preparation and Characterization[M].Second Edition.New York:Wiley-Vch,2000:5-18.
[11] Yi S Q,Chen X R,Cao X,et al.Influencing factors and environmental effects of interactions between goethite and organic matter:A critical review[J].Frontiers in Environmental Science,2022,10:102377.
[12] Li H,Atkins B,Williams S,et al.Sorption and oxidative degradation of small organic molecules on mn-oxides—effects of pH and mineral structures[J].ACS Earth and Space Chemistry,2024,8(10):2067-2077.
[13] Allard S,Gutierrez L,Fontaine Claude,et al.Organic matter interactions with natural manganese oxide and synthetic birnessite[J].Science of the Total Environment,2017,583:487-495.
[14] Trainer E L,M Ginder-Vogel,C K Remucal.Selective reactivity and oxidation of dissolved organic matter by manganese oxides[J].Environmental Science & Technology,2021,55(17):12084-12094.
[15] 自然资源部东海局.2024年中国海洋生态预警监测公报 [EB/OL].(2025-06-20).http://101.231.140.106/gk/gbytj/202506/t20250620_28896.shtml.
[16] Liu S S,Feng W Y,Song F H,et al.Photodegradation of algae and macrophyte-derived dissolved organic matter:A multi-method assessment of DOM transformation[J].Limnologica,2019,77:125683.
[17] Cwiertny D M,Handler R M,Schaefer M V,et al.Interpreting nanoscale size-effects in aggregated Fe-oxide suspensions:Reaction of Fe(Ⅱ) with Goethite.Geochimica et Cosmochimica Acta[J].2008,72(5):1365-1380.
[18] Kester D R,Duedall I W,Connors D N,et al.Preparation of artificial seawater [J].Limnology and Oceanography,1967,12(1):176-179.
[19] Piscataqua Region Estuaries Partnership.State of our estuaries:monitoring and assessment of pH variability in estuarine environments[EB/OL].(2024) https://www.stateofourestuaries.org/2023-reports/sooe-report.
[20] Al-Shehhi M R,Nelson D,Farzanah R,et al.Characterizing algal blooms in a shallow & a deep channel[J].Ocean & Coastal Management,2021,213(2):105840.
[21] Rahman M S,Whalen M,and Gagnon G A,Adsorption of dissolved organic matter (DOM) onto the synthetic iron pipe corrosion scales (goethite and magnetite):Effect of pH[J].Chemical Engineering Journal,2013,234:149-157.
[22] Qin X P,Liu F,Wang G C,et al.Adsorption of humic acid from aqueous solution by hematite:Effects of pH and ionic strength[J].Environmental Earth Sciences,2015,73(8):4011-4017.
[23] Chen W,Westerhoff P,Leenheer J A,et al.Fluorescence excitation-emission matrix regional integration to quantify spectra for dissolved organic matter[J].Environmental Science & Technology,2003,37(24):5701-5710.
[24] Birdwell J E and Engel A S.Characterization of dissolved organic matter in cave and spring waters using UV-Vis absorbance and fluorescence spectroscopy[J].Organic Geochemistry,2010,41(3):270-280.
[25] 盘赛昆，朱强，王淑军，等.条浒苔蛋白质的超声波辅助提取及其性质[J].食品科学，2013,34(18):12-17.Pan S K,Zhu Q,Wang S J,et al.Ultrasonic-assisted extraction and properties of protein from enteromorpha clathrata[J].Food Science,2013,34(18):12-17.
[26] Fernandes P A R,Coimbra M A.The antioxidant activity of polysaccharides:A structure-function relationship overview [J].Carbohydrate Polymers,2023,314:120965.
[27] Hur J and Schlautman M A.Effects of pH and phosphate on the adsorptive fractionation of purified Aldrich humic acid on kaolinite and hematite[J].Journal of Colloid and Interface Science,2004,277(2):264-270.
[28] 章奇，居琪，李健欣，等.针铁矿对湖泊草、藻来源可溶有机质的非均质吸附[J].湖泊科学，2020,32(4):1041-1052.Zhang Q,Ju Q,Li J X,et al.Heterogeneous adsorption of macrophyte-and algae-derived dissolved organic matter on goethite in freshwater lakes[J].Journal of Lake Sciences,2020,32(4):1041-1052.
[29] Stuckey J W,Goodwin C G,Wang J,et al.Impacts of hydrous manganese oxide on the retention and lability of dissolved organic matter[J].Geochemical Transactions,2018,19(1):6.
[30] Thurman E M and Malcolm R L.Structural Study of Humic Substances:New Approaches and Methods[M].US:Ann Arbor Science,1983.
[31] 孟雨.沉积物矿物质组分及组分相互作用对有机磷吸附行为的影响[D].青岛：中国海洋大学，2025.Meng Y.The Influence of Mineral Components in Sediment and Their Interactions on the Sorption Behavior of Organophosphorus[D].Qingdao:Ocean University of China,2025.
[32] Li H,Santos F,Butler B,et al.A critical review on the multiple roles of manganese in stabilizing and destabilizing soil organic matter[J].Environmental Science & Technology,2021,55(18):12136-12152.
基本信息:
DOI：10.16441/j.cnki.hdxb.20250287
中图分类号:X55;P735
引用信息:
[1]韩路,王渝媛,周立敏,等.铁/锰氧化物对藻源有机质的吸附分馏特征研究[J].中国海洋大学学报(自然科学版),2026,56(09):96-105.DOI:10.16441/j.cnki.hdxb.20250287.
基金信息:
国家自然科学基金重点项目(42330402)资助~~
2026-08-31
2026-08-31