Photodegradation of chromophoric dissolved organic matters in the water of Lake Dianchi, China

Abstract

Water samples were taken from Lake Dianchi, on the Yungui Plateau of southwest China, and experiments were conducted to simulate the photochemical degradation characteristic of chromophoric dissolved organic matter (CDOM) in the lake water. Three groups of experiments under different light conditions: ultraviolet (UV) light, visible light, and dark, were done and variations of fluorescence properties, UV absorbance, and dissolved organic carbon (DOC) concentrations during the experiments were analyzed to study the photodegradation process of CDOM with time. The result showed that light irradiation led to significant photochemical degradation of CDOM, resulting in changes in florescent properties, absorbance losses, decreases in aromaticity and average molecular weight, as well as decline in DOC concentration in the water. It was also observed that UV irradiation had greater effect than visible light did. However, various fluorophores had different sensitivities to the same irradiation condition, that is, protein-like fluorophore at the low excitation wavelengths is more sensitive to UV irradiation than the other fluorophores, and is more readily to undergo photo-degradation. In addition, visible light irradiation did not have significant impact on DOC in the water, with DOC concentration decrease by 5.57% –59.9% during the experiment time. These results may provide new knowledge on the environment behavior of CDOM in the water of Lake Dianchi.

Keywords

chromophoric dissolved organic matter / photodegradation / ultraviolet radiation / dissolved organic carbon

References

[1] Rochelle-Newall E J, Fisher T R. Chromophoric dissolved organic matter and dissolved organic carbon in Chesapeake Bay. Marine Chemistry, 2002, 77(1): 23–41

[2] Zhang Y L, Liu M L, Qin B Q, Feng S. Photochemical degradation of chromophoric-dissolved organic matter exposed to simulated UV-B and natural solar radiation. Hydrobiologia, 2009, 627(1): 159–168

[3] Murphy K R, Stedmon C A, Waite T D, Ruiz G M. Distinguishing between terrestrial and autochthonous organic matter sources in marine environments using fluorescence spectroscopy. Marine Chemistry, 2008, 108(1–2): 40–58

[4] Zhang Y L, Zhang E L, Liu M L, Wang X, Qin B Q. Variation of chromophoric dissolved organic matter and possible attenuation depth of ultraviolet radiation in Yunnan Plateau lakes. Limnology, 2007, 8(3): 311–319

[5] Doxaran D, Froidefond J M, Lavender S J, Castaing P. Spectral signature of highly turbid waters application with SPOT data to quantify suspended particulate matter concentrations. Remote Sensing of Environment, 2002, 81(1): 149–161

[6] Biers E J, Zepp R G, Moran M A. The role of nitrogen in chromophoric and fluorescent dissolved organic matter formation. Marine Chemistry, 2007, 103(1–2): 46–60

[7] Stedmon C A, Markager S, Tranvik L, Kronberg L, Slätis T, Martinsen W. Photochemical production of ammonium and transformation of dissolved organic matter in the Baltic Sea. Marine Chemistry, 2007, 104(3–4): 227–240

[8] Blough N V, Del Vecchio R. Chromophoric DOM in the coastal environment. In: Hansell D A, Carlson C A, eds. Biogeochemistry of Marine Dissolved Organic Matter. Cambridge: Academic Press, 2002, 509–546

[9] Gao H, Zepp R G. Factors influencing photoreactions of dissolved organic matter in a coastal river of the southeastern United States. Environmental Science & Technology, 1998, 32(19): 2940–2946

[10] Kieber D J. Photochemical production of biological substrates. In: de Mora S J, Demers S J S, Vernet M, eds. The Effect of UV Radiation in the Marine Environment. Cambridge: Cambridge University Press, 2000, 130–148

[11] Nelson N B, Carlson C A, Steinberg D K. Production of chromophoric dissolved organic matter by Sargasso Sea microbes. Marine Chemistry, 2004, 89(1–4): 273–287

[12] Del Vecchio R, Blough N V. Photobleaching of chromophoric dissolved organic matter in natural waters: kinetics and modeling. Marine Chemistry, 2002, 78(4): 231–253

[13] Morris D P, Hargreaves B P. The role of photochemical degradation of dissolved organic carbon in regulating the UV transparency of three lakes on the Pocono Plateau. Limnology and Oceanography, 1997, 42(2): 239–249

[14] Laurion I, Ventura M, Catalan J, Psenner R, Sommaruga R. Attenuation of ultraviolet radiation in mountain lakes: Factors controlling the among- and within-lake variability. Limnology and Oceanography, 2000, 45(6): 1274–1288

[15] Huovinen P S, Penttilä H, Soimasuo M R. Spectral attenuation of solar ultraviolet radiation in humic lakes in Central Finland. Chemosphere, 2003, 51(3): 205–214

[16] Wu F C, Tanoue E. Molecular mass distribution and fluorescence characteristics of dissolved organic ligands for copper (II) in Lake Biwa, Japan. Organic Geochemistry, 2001, 32(1): 11–20

[17] Kohl S D, Rice J A. The binding of contaminants to humic: A mass balance. Chemosphere, 1998, 36(2): 251–261

[19] Kieber D J, McDaniel J, Mopper K. Photochemical source of biological substrates in sea water: Implication for carbon cycling. Nature, 1989, 341(6243): 637–639

[20] Mopper K, Zhou X, Kieber R J, Kieber D J, Sikorski R J, Jones R D. Photochemieal degradation of dissolved organic carbon and its impact on the oceanic carbon cycle. Nature, 1991, 353(6339): 60–62

[21] Kitidis V. CDOM dynamics and photoammonification in the marine environment. Dissertation for the Doctor Degree Newcastle upon Tyne: Newcastle University, 2002

[22] Bricaud A, Morel A, Prieur L. Absorption by dissolved organic matter of the sea (yellow substance) in the UV and visible domains. Limnology and Oceanography, 1981, 26(1): 43–53

[23] Keith D J, Yoder J A, Freeman S A. Spatial and temporal distribution of coloured dissolved organic matter (CDOM) in narragansett bay, rhode island: implications for phytoplankton in coastal waters. Estuarine, Coastal and Shelf Science, 2002, 55(5): 705–717

[24] Hur J, Hwang S J, Shin J K. Using synchronous fluorescence technique as a water quality monitoring tool for an urban river. Water, Air, and Soil Pollution, 2008, 191(1–4): 231–243

[25] Marhuenda-Egea F C, Martínez-Sabater E, Jordá J, Moral R, Bustamante M A, Paredes C, Pérez-Murcia M D. Dissolved organic matter fractions formed during composting of winery and distillery residues: evaluation of the process by fluorescence excitation-emission matrix. Chemosphere, 2007, 68(2): 301–309

[26] Moran M A, Sheldon W M, Zepp R G. Carbon loss and optical property changes during long-time photochemical and biological degradation of estuarine dissolved organic matter. Limnology and Oceanography, 2000, 45(6): 1254–1264

[27] Grzybowski W. Effect of short-term sunlight irradiation on absorbance spectra of chromophoric organic matter dissolved in coastal and riverine water. Chemosphere, 2000, 40(12): 1313–1318

[28] Skoog A, Wedbrog H, Fogelqvist E. Photobleaching of fluorescence and the organic carbon concentration In a coastal environment. Marine Chemistry, 1996, 55(3–4): 333–345

[29] Moran M A, Zepp R G. Role of photoreaction in the formation of biologically labile compounds from dissolved organic matter. Limnology and Oceanography, 1997, 42(6): 1307–1316

[30] Bertilsson S, Tranvik L J. Photochemically produced carboxylic acids as substrates for freshwater bacterioplankton. Limnology and Oceanography, 1998, 43(5): 885–895

[32] Zhang Y L, Zhang B, Wang X, Li J S, Feng S, Zhao Q H, Liu M, Qin B. A study of absorption characteristics of chromophoric dissolved organic matter and particles in Lake Taihu, China. Hydrobiologia, 2007, 592(1): 105–120

[33] Coble P G, Schultz C A, Mopper K. Fluorescence contouring analysis of DOC intercalibration experiment samples: a comparison of techniques. Marine Chemistry, 1993, 41(1–3): 173–178

[34] Kieber R J, Whitehead R F, Reid S N, Willey J D, Seaton P J. Chromophoric dissolved organic matter (CDOM) in rainwater, Southeastern North Carolina, USA. Journal of Atmospheric Chemistry, 2006, 54(1): 21–41

[35] Coble P G. Characterization of marine and terrestrial DOM in the seawater using exciting-emission matrix spectroscopy. Marine Chemistry, 1996, 51(4): 325–346

[36] Monsallier J M, Scherbaum F J, Buckau G, Kim J I, Kumke M U, Specht C H, Frimmel F H. Influence of photochemical reactions on the complexation of humic acid with europium (III). Journal of Photochemistry and Photobiology A: Chemistry, 2001, 138(1): 55–63

[37] de Haan H. Solar UV-light penetration and photodegradation of humic substances in peaty lake water. Limnology and Oceanography, 1993, 38(5): 1072–1076

[38] Peuravuori J, Pihlaja K. Molecular size distribution and spectroscopic properties of aquatic humic substances. Analytica Chimica Acta, 1997, 337(2): 133–149

[39] Osburn C L, Morris D P. Photochemistry of chromophoric dissolved organic matter in natural waters. In: Helbling E W, Zagarese H, eds. UV Effects in Aquatic Organisms and Ecosystems. Cambridge: The Royal Society of Chemistry, 2003, 187–209

[40] Amon R M W, Benner R. Photochemical and microbial consumption of dissolved organic carbon and dissolved oxygen in the Amazon River system. Geochimica et Cosmochimica Acta, 1996, 60(10): 1783–1792

[42] Vǎlǎtalo A V, Wetzel R G. Photochemical and microbial decomposition of chromophoric dissolved organic matter during long (months-years) exposures. Marine Chemistry, 2004, 89(1–4): 313–326

[43] Xia X H, Li G C, Yang Z F, Chen Y, Huang G H. Effects of fulvic acid concentration and origin on photodegradation of polycyclic aromatic hydrocarbons in aqueous solution: importance of active oxygen. Environmental Pollution, 2009, 157(4): 1352–1359

Acknowledgements

This work was supported by the National Basic Research Program of China (No. 2008CB418201).

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg