Response of Chromophoric Dissolved Organic Matter Composition to Different Hydrological Scenarios in Large Eutrophic Lake Taihu

被引:2
作者
Shi Y. [1 ,2 ]
Zhou Y.-Q. [2 ,3 ]
Zhang Y.-L. [2 ,3 ]
Yao X.-L. [2 ,3 ]
Huang C.-C. [1 ]
机构
[1] College of Geography Science, Nanjing Normal University, Nanjing
[2] State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing
[3] University of Chinese Academy of Sciences, Beijing
来源
Zhang, Yun-Lin (ylzhang@niglas.ac.cn) | 2018年 / Science Press卷 / 39期
关键词
Chromophoric dissolved organic matter(CDOM); Excitation-emission matrices; Lake Taihu; Parallel factor analysis; Spectral absorption;
D O I
10.13227/j.hjkx.201802003
中图分类号
学科分类号
摘要
Chromophoric dissolved organic matter (CDOM) is a fraction of dissolved organic matter that can strongly absorb light in the ultraviolet and blue regions and plays an important role in the biogeochemical cycling of carbon, nitrogen, and phosphorus. Unraveling the sources, optical composition, and corresponding spatial variabilities of CDOM can improve our understanding of carbon, nitrogen, and phosphorus cycling in lakes and lake water quality management. CDOM spectral absorption and fluorescent excitation-emission matrices were measured to investigate the compositional dynamics of CDOM under different hydrological scenarios. Our results showed that the mean value of dissolved organic carbon (DOC) concentration of (8.11±1.26) mg•L -1 in the rainy season was significantly higher than that in the dry season (3.53±1.19) mg•L -1 (t-test, P<0.01), whereas the mean spectral slope S 275-295 of (20.89±1.90) μm -1 in the dry season was significantly greater than that in the rainy season (19.09±1.81) μm -1 (t-test, P<0.001). Three fluorescent components were identified using parallel factor analysis, and we further found that the dynamics of the three CDOM components were strongly influenced by hydrological conditions. Fluorescence intensity (F max ) of the terrestrial humic-rich component C2 increased with increasing water levels and rainfall. Significant negative relationships were found between all three fluorescent components and dissolved oxygen (P<0.01), suggesting that all three components served as important substrates for microbial processing. Significant positive relationships were found between the terrestrial humic-rich C2 and tryptophan-like C1 and chlorophyll-a and chemical oxygen demand, indicating that anthropogenic inputs and algal degradation contributed significantly to the CDOM pool in Lake Taihu. We further found a significant positive relationship between DOC concentration and F max of terrestrial humic-rich C2 (r 2 =0.58, P<0.001), suggesting that DOC in Lake Taihu was primarily derived from allochthonous input. © 2018, Science Press. All right reserved.
引用
收藏
页码:4915 / 4924
页数:9
相关论文
共 48 条
[1]  
Organelli E., Bricaud A., Antoine D., Et al., Seasonal dynamics of light absorption by chromophoric dissolved organic matter (CDOM) in the NW Mediterranean Sea (BOUSSOLE site), Deep Sea Research Part I: Oceanographic Research Papers, 91, pp. 72-85, (2014)
[2]  
Zhang Y.L., Wu S.C., Qin B.Q., Et al., Absorption of light by chromophoric dissolved organic matter (CDOM) in Meiliang Bay of Taihu Lake, China Environmental Science, 24, 4, pp. 405-409, (2004)
[3]  
Le C., Lehrter J.C., Hu C., Et al., Relation between inherent optical properties and land use and land cover across Gulf Coast estuaries, Limnology and Oceanography, 60, 3, pp. 920-933, (2015)
[4]  
Zhang Y.L., Gao G., Shi K., Et al., Absorption and fluorescence characteristics of rainwater CDOM and contribution to Lake Taihu, China, Atmospheric Environment, 98, pp. 483-491, (2014)
[5]  
Wada S., Aoki M.N., Tsuchiya Y., Et al., Quantitative and qualitative analyses of dissolved organic matter released from Ecklonia cava Kjellman, in Oura Bay, Shimoda, Izu Peninsula, Japan, Journal of Experimental Marine Biology and Ecology, 349, 2, pp. 344-358, (2007)
[6]  
Fukushima T., Park J.C., Imai A., Et al., Dissolved organic carbon in a eutrophic lake
[7]  
dynamics, biodegradability and origin, Aquatic Sciences, 58, 2, pp. 139-157, (1996)
[8]  
Zhang Y.L., Zhang E.L., Yin Y., Et al., Characteristics and sources of chromophoric dissolved organic matter in lakes of the Yungui Plateau, China, differing in trophic state and altitude, Limnology and Oceanography, 55, 6, pp. 2645-2659, (2010)
[9]  
Zanardi-Lamardo E., Moore C.A., Zika R.G., Seasonal variation in molecular mass and optical properties of chromophoric dissolved organic material in coastal waters of southwest Florida, Marine Chemistry, 89, 1-4, pp. 37-54, (2004)
[10]  
Osburn C.L., Morris D.P., Photochemistry of chromophoric dissolved organic matter in natural waters, UV Effects in Aquatic Organisms and Ecosystems, pp. 187-209, (2003)