Does reduced sediment load contribute to increased outbreaks of harmful algal blooms off the Changjiang Estuary?
-
摘要: 过去几十年来全球近海有害藻华(又称赤潮)发生频率持续增加。人类活动造成的河口-近海富营养化程度的加剧,被认为是导致全球有害藻华增加的主要原因。但是,富营养化程度的加剧可能不是全球有害藻华增加的惟一原因。河流入海的非营养盐类的其他物质通量变异(如泥沙),也可能显著影响河口-近海的生物活动乃至赤潮的发生。过去40年来随着长江入海营养盐通量的增加,长江入海泥沙通量减少了70%。长期观测资料显示,由于泥沙减少使得长江口羽状流区光照条件显著改善,长江口浮游植物生物量最大值区已扩展至更低盐度的区域。此外,过去40年来长江口赤潮发生频率变化与长江入海泥沙通量变化呈现镜像关系,且二者呈显著的负相关关系。因此认为,长江入海泥沙的剧烈减少降低了羽状流区水体浊度,从而对长江口区赤潮频率的增加有一定贡献。Abstract: Harmful algal blooms (HABs) have been increasingly frequent in coastal waters around the world over the last several decades. Accelerated coastal eutrophication, resulting from the increased anthropogenic loadings of nutrients, is commonly assumed to be the primary cause of this increase. However, although important, accelerated coastal eutrophication may not be the only explanation for the increasing blooms or toxic outbreaks in estuarine waters. Changes in riverine material fluxes other than nutrients, such as sediment load, may significantly affect biological activities and HAB incidence in estuarine and coastal waters. A case study off the Changjiang (Yangtze River) Estuary indicated that with the increasing riverine loadings of nutrients, the sediment load from the Changjiang River has been reduced by 70% over the past four decades. A comparison of long-term data revealed that the phytoplankton biomass maximum has expanded to a region of much lower salinity due to the drastic reduction in riverine sediment load and the subsequent improvement in light penetration in the Changjiang River plume. Furthermore, there was an apparent mirror-image relationship between the sediment load from the Changjiang River and the HAB incidence off the Changjiang Estuary over the past four decades, and the number of HAB incidents was significantly negatively correlated with the sediment load. Therefore, it is argued that the drastic decline in sediment load from the Changjiang River reduced turbidity in the Changjiang Estuary and thus contributed to the increased frequency of HABs in the buoyant discharge plumes.
-
Anderson D M, Glibert P M, Burkholder J M. 2002. Harmful algal blooms and eutrophication:Nutrient sources, composition, and consequences. Estuaries, 25(4):704-726 Bode A, Dortch Q. 1996. Uptake and regeneration of inorganic nitro-gen in coastal waters influenced by the Mississippi River spa- tial and seasonal variations. Journal of Plankton Research, 18:2251-2268 Cao Peikui, Yan Suzhuang. 1996. Suspended sediments front and its impacts on the materials transport of the Changjiang Estuary. Journal of East China Normal University (Natural Science) (in Chinese), (1):85-94 Chai Chao, Yu Zhiming, Shen Zhiliang, et al. 2009. Nutrient charac-teristics in the Yangtze River Estuary and the adjacent East China Sea before and after impoundment of the Three Gorges Dam. Science of the Total Environment, 407:4687-4695 Chai Chao, Yu Zhiming, Song Xiuxian, et al. 2006. The status and characteristics of eutrophication in the Yangtze River (Changji-ang) estuary and the adjacent East China Sea, China. Hydrobio-logia, 563:313-328 Chen Changsheng, Zhu Jianrong, Beardsley R C, et al. 2003. Physical-biological sources for dense algal blooms near the Changjiang River. Geophysical Research Letters, 30(10):1515 Cloern J E. 1987. Turbidity as a control on phytoplankton biomass and productivity in estuaries. Continental Shelf Research, 7:1367-1381 Dagg M, Benner R, Lohrenz S, et al. 2004. Transformation of dis-solved and particulate materials on continental shelves influ-enced by large rivers:plume processes. Continental Shelf Re-search, 24:833-858 DeMaster D J, Kuehl S A, Nittrouer C A. 1986. Effects of suspended sediments on geochemical processes near the mouth of the Amazon River:examination of biological silica uptake and the fate of particle-reactive elements. Continental Shelf Research, 6:107-125 DeMaster D J, Smith W O Jr, Nelson D M, et al. 1996. Biogeochemical processes in Amazon shelf waters:chemical distributions and uptake rates of silicon, carbon and nitrogen. Continental Shelf Research, 16:617-643 Edmond J M, Spivack A, Grant B C, et al. 1985. Chemical dynamics of the Changjiang Estuary. Continental Shelf Research, 4:17-36 Gao Shu, Cheng Peng, Wang Yaping, et al. 2000. Characteristics of suspended sediment concentrations over the areas adjacent to Changjiang River Estuary, the summer of 1998. Marine Science Bulletin, 2(1):14-24 Gao Shu, Wang Yaping. 2008. Changes in material fluxes from the Changjiang River and their implications on the adjoining con-tinental shelf ecosystem. Continental Shelf Research, 28:1490-1500 Gu Guochuan. 1986. Distribution of suspended silt in an area off Changjiang Estuary. Donghai Marine Science (in Chinese), 4(1):12-20 Guo Yujie, Yang Zeyu. 1992. Ecological analysis and biomass vari-ation of the phytoplankton in the Changjiang Estuary. Studia Marina Sinica (in Chinese), 33:167-190 He Chao, Ding Pingxing, Kong Yazhen. 2008. Analysis of temporal and spatial variation characteristics of suspended sediment concentration of the Yangtze estuary and adjacent sea areas in flood seasons. Journal of East China Normal University (Natur-al Science) (in Chinese), (2):15-21 Heisler J, Glibert P M, Burkholder J M, et al. 2008. Eutrophication and harmful algal blooms:A scientific consensus. Harmful Algae, 8(1):3-13 Hu Gang, Liu Jian, Shi Liangqiang. 2011. The characteristics of sus-pended deposits in the offshore area of the Changjiang Estuary during flood season. Marine Geology Frontier (in Chinese), 27(9):6-10 Li Hongmei, Tang Hongjie, Shi Xiaoyong, et al. 2014. Increased nutri-ent loads from the Changjiang (Yangtze) River have led to in-creased Harmful Algal Blooms. Harmful Algae, 39:92-101 Lin Jun, Zhu Jianrong, Zhang Jing, et al. 2011. Distribution of phyto-plankton biomass and its relationships with the environmental factors off the Changjiang (Yangtze River) Estuary. Journal of Fisheries of China (in Chinese), 35(1):74-87 Liu Fang, Huang Haijun, Gao Ang. 2006. Distribution of suspended matter on the Yellow Sea and the East China Sea and effect of ocean current on its distribution. Marine Science (in Chinese), 30(1):68-72 Liu Lusan, Zhou Juan, Zheng Binghui, et al. 2013. Temporal and spa-tial distribution of red tide outbreaks in the Yangtze River Estu-ary and adjacent waters, China. Marine Pollution Bulletin, 72(1):213-221 Lohrenz S E, Dagg M J, Whitledge T E. 1990. Enhanced primary pro-duction at the plume/oceanic interface of the Mississippi River. Continental Shelf Research, 10:639-664 Lohrenz S E, Fahnenstiel G L, Redalje D G, et al. 1999. Nutrients, irra-diance, and mixing as factors regulating primary production in coastal waters impacted by the Mississippi River plume. Con-tinental Shelf Research, 19:1113-1141 MWR (The Ministry of Water Resources of China). 2015. China River Sediment Bulletin (2000-2012). http://www.mwr.gov.cn/zwzc/hygb/zghlnsgb/ Nilsson C, Reidy C A, Dynesius M, et al. 2005. Fragmentation and flow regulation of the world's large river systems. Science, 308:405-408 Ning Xiuren, Kutti C. 1991. Relationships between the chlorophyll, bacteria, ATP, POC and microbial respiration rate in the Changjiang Estuary and its diluted water area. Haiyang Xuebao (in Chinese), 13(6):831-837 Ning Xiuren, Vaulot D, Liu Zhensheng, et al. 1988. Standing stock and production of phytoplankton in the estuary of the Changjiang (Yangtze River) and the adjacent East China Sea. Marine Eco-logy Progress Series, 49:141-150 Pang Chongguang, Wang Fan, Bai Xuezhi, et al. 2003. Distribution features of suspended matter and amount of sediment at the Changjiang Estuary and adjacent area. Marine Science (in Chinese), 27(12):31-35 Parsons T R, Maita Y, Lalli C M. 1984. A Manual of Chemical and Bio-logical Methods for Seawater Analysis. Oxford:Pergamon Press, 173 Sellner K G, Doucette G J, Kirkpatrick G J. 2003. Harmful algal blooms:causes, impacts and detection. Journal of Industrial Microbiology & Biotechnology, 30(7):383-406 Shao Hebin, Fan Dejiang, Mai Xiaolei, et al. 2013. Types and size of suspended particles in a typical cross section at the Changjiang Estuary and influence factors. Marine Geology & Quaternary Geology (in Chinese), 33(3):47-56 Shao Hebin, Fan Dejiang, Zhang Jing, et al. 2012. Distribution and in-fluencing factors of suspended matters and chlorophyll in Au-tumn in Yangtze River Estuary post-Three Gorges Dam. Period-ical of Ocean University of China (in Chinese), 42(5):94-104 Shao Mihua, Li Yan, Wang Zhengfang, et al. 1996. The spatial and temporal variation of suspended substance in the Changjiang Estuary Area. Marine Environmental Science (in Chinese), 15(3):36-40 Shen Fang, Zhou Yunxuan, Li Jiufa, et al. 2013. Remotely sensed vari-ability of the suspended sediment concentration and its re-sponse to decreased river discharge in the Yangtze estuary and adjacent coast. Continental Shelf Research, 69:52-61 Shen Xinqiang, Hu Fangxi. 1995. Basic characteristics of distribution of chlorophyll a in the Changjiang Estuary. Journal of Fishery Sciences of China (in Chinese), 2(1):71-80 Shen Zhiliang. 1993. A study on the relationships of the nutrients near the Changjiang River Estuary with the flow of the Changji-ang River Water. Chinese Journal of Oceanology and Limno-logy, 11(3):260-267 Smith W O Jr, DeMaster D J. 1996. Phytoplankton biomass and pro-ductivity in the Amazon River plume:correlation with seasonal river discharge. Continental Shelf Research, 16:291-319 SOA (State Oceanic Administration of China). 2015. China Marine Disaster Bulletin (1989-2012). http://www.soa.gov.cn/zwgk/hygb/zghyzhgb/ Song Hongjun, Zhang Xuelei, Wang Baodong, et al. 2014. Bottom-up and top-down controls of the phytoplankton standing stock off the Changjiang Estuary. Haiyang Xuebao (in Chinese), 36(8):91-100 Song Xiaohong, Shi Xuefa, Cai Deling, et al. 2007. Distributions of TSM, POC and PN in the Changjiang Estuary area in autumn after the river closure at Three Gorges. Advances in Marine Sci-ence (in Chinese), 25(2):168-177 Sternberg R W, Larsen L H, Miao Y T. 1985. Tidally driven sediment transport on the East China Sea continental shelf. Continental Shelf Research, 4:105-120 Sun Baiye. 2008. Effects of irradiance on growth of phytoplankton in the Changjiang Estuary and adjacent coastal waters (in Chinese)[dissertation]. Qingdao:Ocean University of China, 1-138 Syvitski J P M, V.r.smarty C J, Kettner A J, et al. 2005. Impact of hu-mans on the flux of terrestrial sediment to the global coastal ocean. Science, 308:376-380 Tian R C, Hu F X, Martin J M. 1993. Summer nutrient fronts in the Changjiang (Yantze River) Estuary. Estuarine, Coastal and Shelf Science, 37:27-41 Tian T, Merico A, Su J, et al. 2009. Importance of resuspended sedi-ment dynamics for the phytoplankton spring bloom in a coastal marine ecosystem. Journal of Sea Research, 62:214-228 Turner R E, Rabalais N N, Nan Z Z. 1990. Phytoplankton biomass, production and growth limitations on the Huanghe (Yellow River) continental shelf. Continental Shelf Research, 10:545-571 Wang Baodong. 2006. Cultural eutrophication in the Changjiang (Yangtze River) plume:history and perspective. Estuarine, Coastal and Shelf Science, 69:471-477 Wang Xiulin, Sun Xia, Han Xiurong, et al. 2004. Comparison in mi-cronutrient distributions and composition for the high fre-quency HAB occurrence areas in the East China Sea between summer and spring 2002. Oceanologia et Limnologia Sinica (in Chinese), 35(4):323-331 Wang Xiulin, Wang Baodong, Zhang Chuansong, et al. 2008. Nutrient composition and distributions in coastal waters impacted by the Changjiang plume. Acta Oceanologica Sinica, 27(5):111-125 Wang Changyou, Wang Xiulin, Liang Shengkang, et al. 2010. The methods for calibrating average concentration in the domain and estimating average annual concentration of pollutants in the sea area being partially or totally different from target do-mains. Haiyang Xuebao (in Chinese), 32(2):155-160 Wang Baodong, Wei Qinsheng, Chen Jianfang, et al. 2012. Annual cycle of hypoxia off the Changjiang (Yangtze River) Estuary. Marine Environmental Research, 77:1-5 Wang Jinhui, Wu Jianyong. 2009. Occurrence and potential risks of harmful algal blooms in the East China Sea. Science of the Total Environment, 407(13):4012-4021 Xu Kehui, Milliman J D. 2009. Seasonal variations of sediment dis-charge from the Yangtze River before and after impoundment of the Three Gorges Dam. Geomorphology, 104:276-283 Yang Bo. 2012. Effects of the Three Gorges Dam on the biogeochem-istry of the plume front in the Changjiang Estuary (in Chinese)[dissertation]. Qingdao:The First Institute of Oceanography, SOA, 1-80 Yang Z, Wang H, Saito Y, et al. 2006. Dam impacts on the Changjiang (Yangtze) River sediment discharge to the sea:The past 55 years and after the Three Gorges Dam. Water Resources Re-search, 42(4):501-517 Zhai Shikui, Meng Wei, Yu Zhigang. 2008. Environment of the Changjiang Estuary after the Impoundment of the Three Gorges Dam (in Chinese). Beijing:Science Press, 51-111 Zhou Weihua, Yuan Xiangcheng, Huo Wenyi, et al. 2004. Distribu-tion of chlorophyll a and primary productivity in the adjacent sea area of Changjiang River Estuary. Haiyang Xuebao (in Chinese), 26(3):143-150
点击查看大图
计量
- 文章访问数: 1155
- HTML全文浏览量: 50
- PDF下载量: 747
- 被引次数: 0