Occurrence of cyanobacterial blooms can induce considerable patchiness in the quantity and quality of dissolved organic matter (DOM). The present study investigated the changes of dissolved organic carbon (DOC), chromophoric DOM (CDOM) and fluorescent DOM (FDOM) in an inoculated 32-day laboratory incubation. The biodegradation of individual FDOM components was further studied using parallel factor analysis (PARAFAC) and two dimension correlation spectroscopy (2D-COS). The results showed that the DOC concentration decreased significantly initially, followed by a slow biodegradation. Fitting by G model successfully separated the DOC into labile (40%), semi-labile (37%) and refractory (23%) pools, suggesting that 77% of the DOC can be metabolized quickly after its production. The values of SUVA254, spectral slope ratio, and HIX indicated that the aromaticity, molecular weight, and humic degree of DOM increased with biodegradation. The bioavailability of 4PARAFAC components followed the order of:tyrosine-> tryptophan-> fulvic acid-> humic acid-like component. Tyrosine-and tryptophan-like component accounted for a large proportion of the labile and semi-labile DOM, while the refractory DOM was mainly composed of fulvic-acid-and humic acid-like component. Synchronous fluorescence spectra combined with 2D-COS revealed that the fluorescent compounds with lower excitation wavelengths were preferentially biodegraded.
许明, 刘伟京, 白永刚, 涂勇. 太湖蓝藻水华期可溶有机物的生物降解[J]. 中国环境科学, 2018, 38(9): 3494-3501.
XU Ming, LIU Wei-jing, BAI Yong-gang, TU Yong. Biodegradation of dissolved organic matter in Lake Taihu during cyanobacterial blooms. CHINA ENVIRONMENTAL SCIENCECE, 2018, 38(9): 3494-3501.
Zhang Y L, Liu X H, Wang M Z, et al. Compositional differences of chromophoric dissolved organic matter derived from phytoplankton and macrophytes[J]. Organic Geochemistry, 2013,55:26-37.
[3]
Philippe A, Schaumann G E. Interactions of dissolved organic matter with natural and engineered inorganic colloids:A review[J]. Environmental Science & Technology, 2014,48(16):8946-8962.
[4]
Cory R M, Kaplan L A. Biological lability of streamwater fluorescent dissolved organic matter[J]. Limnology and Oceanography, 2012, 57(5):1347-1360.
[5]
Wear E K, Carlson C A, James A K, et al. Synchronous shifts in dissolved organic carbon bioavailability and bacterial community responses over the course of an upwelling-driven phytoplankton bloom[J]. Limnology and Oceanography, 2015,60(2):657-677.
Tan D T, Temme H R, Arnold W A, et al. Estrone degradation:Does organic matter (quality), matter?[J]. Environmental Science & Technology, 2015,49(1):498-503.
Hansen A M, Kraus T E C, Pellerin B A, et al. Optical properties of dissolved organic matter (DOM):Effects of biological and photolytic degradation[J]. Limnology and Oceanography, 2016,61(3):1015-1032.
Hur J, Jung K Y, Jung Y M. Characterization of spectral responses of humic substances upon UV irradiation using two-dimensional correlation spectroscopy[J]. Water Research, 2011,45(9):2965-2974.
[15]
Hosen J D, Mcdonough O T, Febria C M, et al. Dissolved organic matter quality and bioavailability changes across an urbanization gradient in headwater streams[J]. Environmental Science & Technology, 2014,48(14):7817-7824.
[16]
Mcdowell W H, Zsolnay A, Aitkenhead-Peterson J A, et al. A comparison of methods to determine the biodegradable dissolved organic carbon from different terrestrial sources[J]. Soil Biology & Biochemistry, 2006,38(7):1933-1942.
[17]
Murphy K R, Stedmon C A, Graeber D, et al. Fluorescence spectroscopy and multi-way techniques. PARAFAC[J]. Analytical Methods, 2013,5(23):6557-6566.
[18]
Weishaar J L, Aiken G R, Bergamaschi B A, et al. Evaluation of specific ultraviolet absorbance as an indicator of the chemical composition and reactivity of dissolved organic carbon[J]. Environmental Science & Technology, 2003,37(20):4702-4708.
[19]
Helms J R, Stubbins A, Ritchie J D, et al. Absorption spectral slopes and slope ratios as indicators of molecular weight, source, and photobleaching of chromophoric dissolved organic matter[J]. Limnology and Oceanography, 2008,53(3):955-969.
[20]
Baker A, Bolton L, Newson M, et al. Spectrophotometric properties of surface water dissolved organic matter in an afforested upland peat catchment[J]. Hydrological Processes, 2008,22(13):2325-2336.
[21]
Cory R M, Mcneill K, Cotner J P, et al. Singlet oxygen in the coupled photochemical and biochemical oxidation of dissolved organic matter[J]. Environmental Science & Technology, 2010,44(10):3683-3689.
[22]
Huguet A, Vacher L, Relexans S, et al. Properties of fluorescent dissolved organic matter in the Gironde Estuary[J]. Organic Geochemistry, 2009,40(6):706-719.
[23]
Sleighter R L, Cory R M, Kaplan L A, et al. A coupled geochemical and biogeochemical approach to characterize the bioreactivity of dissolved organic matter from a headwater stream[J]. Journal of Geophysical Research-Biogeosciences, 2014,119(8):1520-1537.
[24]
Saadi I, Borisover M, Armon R, et al. Monitoring of effluent DOM biodegradation using fluorescence, UV and DOC measurements[J]. Chemosphere, 2006,63(3):530-539.
[25]
Ohno T, Parr T B, Gruselle M C I, et al. Molecular composition and biodegradability of soil organic matter:A case study comparing two new England forest types[J]. Environmental Science & Technology, 2014,48(13):7229-7236.
[26]
Nguyen M L, Westerhoff P, Baker L, et al. Characteristics and reactivity of algae-produced dissolved organic carbon[J]. Journal of Environmental Engineering-Asce, 2005,131(11):1574-1582.
[27]
Maie N, Scully N M, Pisani O, et al. Composition of a protein-like fluorophore of dissolved organic matter in coastal wetland and estuarine ecosystems[J]. Water Research, 2007,41(3):563-570.
[28]
Korak J A, Wert E C, Rosario-Ortiz F L. Evaluating fluorescence spectroscopy as a tool to characterize cyanobacteria intracellular organic matter upon simulated release and oxidation in natural water[J]. Water Research, 2015,68:432-443.
Lee B M, Seo Y S, Hur J. Investigation of adsorptive fractionation of humic acid on graphene oxide using fluorescence EEM-PARAFAC[J]. Water Research, 2015,73:242-251.
[31]
Zang X, Van Heemst J D H, Dria K J, et al. Encapsulation of protein in humic acid from a histosol as an explanation for the occurrence of organic nitrogen in soil and sediment[J]. Organic Geochemistry, 2000,31(7/8):679-695.
[32]
Guillemette F, Del Giorgio P A. Reconstructing the various facets of dissolved organic carbon bioavailability in freshwater ecosystems[J]. Limnology and Oceanography, 2011,56(2):734-748.
[33]
Noda I, Ozaki Y. Two-dimensional correlation spectroscopy:applications in vibrational and optical spectroscopy[M]. London:John Wiley and Sons Inc., 2005.
