引用本文: | 陈文权,孟洋洋,单延功,李香华,王炜,张民.寡—中营养型水体偶发性蓝藻水华的驱动因素分析——以南京方便水库为例.湖泊科学,2022,34(5):1452-1460. DOI:10.18307/2022.0504 |
| Chen Wenquan,Meng Yangyang,Shan Yangong,Li Xianghua,Wang Wei,Zhang Min.The driving forces of sporadic cyanobacterial blooms in oligo-meso trophic waters: A case study of Fangbian Reservoir, Nanjing. J. Lake Sci.2022,34(5):1452-1460. DOI:10.18307/2022.0504 |
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摘要: |
寡—中营养型水体中,虽然营养盐水平偏低,但仍会偶发性出现较为严重的蓝藻水华现象,其具体机制仍有待深入探索研究. 本研究以偶发水华水体方便水库为例,通过历史数据分析和调查研究,探讨了其水华蓝藻的优势类群,并分析了蓝藻水华形成的主要驱动因素. 研究发现:方便水库优势的水华蓝藻为浮丝藻和长孢藻,这两种丝状蓝藻是发生偶发性蓝藻水华的潜在风险物种,其中浮丝藻的发生风险最高,风险时段为7—9月. 方便水库多年来营养盐浓度呈现下降的趋势,其中总氮浓度的下降趋势快于总磷浓度,整体有利于蓝藻水华的防控,但是营养盐的波动,尤其是随着降雨导致的地表径流入库对水体总磷的脉冲式补充,降低了水体氮磷比,增加了水库偶发蓝藻水华的风险; 在营养盐满足的条件下,水温、高锰酸盐指数和氧化还原电位是发生浮丝藻水华的主要驱动因素,氧化还原电位、水温和透明度是发生长孢藻水华的主要驱动因素. 本研究结果有助于提升对偶发性蓝藻水华机制的认识和应急处置工作的精准性. |
关键词: 寡—中营养 偶发性水华 方便水库 蓝藻 |
DOI:10.18307/2022.0504 |
分类号: |
基金项目:南京市水务科研项目(202003)和国家自然科学基金项目(32171546, 31870447)联合资助 |
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The driving forces of sporadic cyanobacterial blooms in oligo-meso trophic waters: A case study of Fangbian Reservoir, Nanjing |
Chen Wenquan1, Meng Yangyang2,3, Shan Yangong4, Li Xianghua4, Wang Wei5, Zhang Min2
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1.Jiangsu Province Hydrology and Water Resources Investigation Bureau, Nanjing 210009, P. R. China;2.State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, P. R. China;3.Nanjing School, University of Chinese Academy of Sciences, Nanjing 211135, P. R. China;4.Nanjing Branch of Jiangsu Province Hydrology and Water Resources Investigation Bureau, Nanjing 210008, P. R. China;5.Nanjing Water Resources Management Center, Nanjing 210008, P. R. China
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Abstract: |
Although sporadic cyanobacterial blooms have been reported in many oligo-meso trophic waters, it is still unclear about the mechanism of cyanobacterial blooms forming in these waters. The study took Fangbian Reservoir in Nanjing as a case to identify the dominant bloom-forming cyanobacteria and analyze the primary driving forces affecting their dominance. The results showed that Planktothrix and Dolichospermum were the dominant cyanobaceteria which contributed to the occasionally occurring cyanobacterial blooms in the reservoir. Planktothrix was the species with greatest potential risks for blooming, which might occurred in July to September. Nutrient concentrations decreased significantly, in which total nitrogen decreased fast than total phosphorus. This situation was favor for cyanobacterial blooms control. However, fluctuation of nutrients, particularly the reduced C/P ratio, induced by the pulse compensation for phosphorus from surface runoffs in south catchment, might be the primary reason for those occasionally occurring cyanobacterial blooms in the reservoir. When nutrient demands for the growth of the two cyanobacteria was met, the dominance of Planktothrix were driven mainly by water temperature, CODMn and oxidation-reduction potential (ORP), and the dominance of Dolichospermum were driven by ORP, water temperature and transparency. These results were helpful to understand the forming mechanism of cyanobacterial blooms in oligo-meso trophic waters. |
Key words: Oligo-meso trophic sporadic blooms Fangbian Reservoir Cyanobacteria |