曝气扰动下弱光照促进蓝藻水华向硅藻优势演替  

Weak light promotes the algal succession from bloomed Microcystis towards diatom dominance under aeration disturbance

作　　者：田亿 王小冬[1] 车轩[1] 潘恒丰 王洪 刘兴国[1] TIAN Yi;WANG Xiaodong;CHE Xuan;PAN Hengfeng;WANG Hong;LIU Xingguo(Fishery Machinery and Instrument Research Institute,Chinese Academy of Fishery Sciences,Shanghai 200092,China;College of Fisheries and Life Science,Shanghai Ocean University,Shanghai 201306,China)

机构地区：[1]中国水产科学研究院渔业机械仪器研究所,上海200092 [2]上海海洋大学水产与生命学院,上海201306

出　　处：《农业环境科学学报》2024年第10期2375-2383,共9页Journal of Agro-Environment Science

基　　金：国家重点研发计划“蓝色粮仓”重点专项(2019YFD0900305)。

摘　　要：为研究持续的曝气扰动下,遮光和蓝藻水华浓度对蓝藻水华尤其藻类群落结构的影响,在玻璃温室中进行蓝藻门微囊藻属(Microcystis)水华的调控实验。实验为2个藻类浓度和2个光照强度的正交实验,共4个处理。按微囊藻水华初始浓度分为低浓度(处理Ⅰ、Ⅲ)和高浓度(处理Ⅱ、Ⅳ),以叶绿素a(Chla)浓度分别表示为384.32μg·L^(-1)和736.21μg·L^(-1);处理Ⅰ、Ⅱ和Ⅲ、Ⅳ分别对应弱光条件(遮光率为99.4%)和强光条件(遮光率为72.8%)。实验过程中,各处理Chla浓度由高到低排序为Ⅳ>Ⅲ>Ⅱ>Ⅰ(P<0.01),均出现了微囊藻向其他藻类的演替。其中弱光条件下的处理Ⅰ、Ⅱ以硅藻门菱形藻属(Nitzchia)为最大优势属,其湿质量占比分别达到90.48%±9.29%和93.64%±2.28%。处理Ⅲ、Ⅳ中,蓝藻门仍占最大优势,处理Ⅲ以席藻(Phormidium)为最大优势属,微囊藻和菱形藻次之,处理Ⅳ以微囊藻为最大优势属,菱形藻和席藻次之。研究表明,持续的曝气扰动下,遮光形成的弱光照是影响蓝藻水华向硅藻优势演替的重要因素,利用水动力扰动进行蓝藻水华调控时需要同时考虑弱光照条件和蓝藻水华生物量的影响。To study the effects of light shading and the biomass of cyanobacterial blooms on the algal community succession under continuous aeration disturbance,an experiment on Microcystis bloom control was conducted in a greenhouse.The experiment was an orthogonal test with four treatments(treatmentsⅠ,Ⅱ,Ⅲ,andⅣ)of both two gradients of algal biomass and light shading.The initial Microcystis bloom biomass was shown in chlorophyll a(Chla).Both treatmentsⅠandⅢwere in a low biomass of 384.32μg·L^(-1) Chla,and treatmentsⅡandⅣwere in a high biomass of 736.21μg·L^(-1) Chla.TreatmentsⅠandⅡwere under weak light with a shading rate of 99.4%,and treatmentsⅢandⅣwere under comparatively strong light with a shading rate of 72.8%.During the experiment,the Chla concentration in each treatment gradually decreased,and the rank order from high to low wasⅣ>Ⅲ>Ⅱ>Ⅰ(P<0.01),and they all succeeded from Microcystis dominance to other algae dominance.The diatom Nitzchia was the most dominant genus in both treatmentsⅠandⅡwith weak light conditions,in which the wet biomass accounted for 90.48%±9.29% and 93.64%±2.28%,respectively.In both treatmentsⅢandⅣ,cyanophyta dominated,in treatmentⅢ,Phormidium was the most dominant genus,followed by Microcystis and Nitzchia,and in treatmentⅣ,Microcystis was the most dominant genus,followed by Nitzchia and Phormidium.The results showed that the weak light caused by shading was an important factor affecting the algal succession from bloomed Microcystis towards diatom dominance.When using hydrodynamic disturbances to regulate cyanobacterial blooms,it is necessary to consider both the effects of light shading conditions and the biomass of the bloomed cyanobacteria.

关 键 词：微囊藻水华 藻类群落结构 曝气扰动 遮光率 硅藻 

分 类 号：X52[环境科学与工程—环境工程] X173