极小曲丝藻生长与光合活性对硅浓度的响应  

Responses of growth and photosynthetic activities of Achnanthidium minutissimum to silicon concentration

作　　者：熊珍珍 毕永红[1] XIONG Zhenzhen;BI Yonghong(Institute of Hydrobiology,Chinese Academy of Sciences,State Key Laboratory of Freshwater Ecology and Biotechnology,Wuhan 430072,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院水生生物研究所,淡水生态与生物技术国家重点实验室,武汉430072 [2]中国科学院大学,北京100049

出　　处：《生态科学》2023年第3期30-36,共7页Ecological Science

基　　金：湖北省技术创新专项重大项目“虾-稻高效养殖与质量安全控制关键技术研发”(2019AB077);“十三五”水专项南水北调中线输水水质预警与业务化管理平台(2017ZX07108-001)。

摘　　要：为探究南水北调中线干渠硅藻快速增殖与硅浓度间的内在关系,选取干渠全年优势种极小曲丝藻(Achnanthidium minutissimum)为研究对象,研究不同初始硅浓度(0、2、4、6和8 mg·L^(−1))对极小曲丝藻生长和光合生理特性的影响。结果显示,不同浓度硅对极小曲丝藻比生长速率具有显著影响(P<0.05)。硅浓度0 mg·L^(−1)时,细胞密度、比生长速率、叶绿素a浓度、类胡萝卜素浓度和光合系统Ⅱ(PSⅡ)最大光化学效率(Fv/Fm)相对于添加硅的试验组,均显著降低(P<0.05),未出现明显的叶绿素荧光诱导曲线(OJIP)特征,检测不到光合放氧。随硅浓度升高(2®8 mg·L^(−1)),藻细胞密度、比生长速率和最大现存生物量均明显上升;硅浓度2 mg·L^(−1)处理组的细胞叶绿素a和类胡萝卜素浓度均显著低于另外3个硅处理组(P<0.05)。硅浓度4 mg·L^(−1)、6 mg·L^(−1)和8 mg·L^(−1)处理组的细胞叶绿素a和类胡萝卜素浓度、F_(v)/F_(m)和光合放氧速率均无显著差异。研究表明硅是硅藻快速增殖的限制因素;中线干渠内硅浓度较高(约5 mg·L^(−1)),满足硅藻大量增殖需要,是导致硅藻快速增殖、占据优势的重要因子。In order to explore the relationship between diatom proliferation and silicon concentration in the main channel of the Middle Route of the South-to-North Water Diversion Project,Achnanthidium minutissimum,a dominant species throughout the year,was selected as the object of this study.The effects of different initial silicon concentrations(0,2,4,6 and 8 mg·L^(−1))on the growth and photosynthetic physiological characteristics of Achnanthidium minutissimum were investigated.The results showed that different silicon concentrations had a significant effect on the specific growth rate of Achnanthidium minutissimum(P<0.05).When the silicon concentration was 0 mg·L^(−1),the concentration of chlorophyll a and carotenoid,and the maximum photochemical efficiency of the photosynthetic systemⅡ(Fv/Fm)were all significantly decreased compared to the groups which added silicon(P<0.05),and the chlorophyll fluorescence induction curve(OJIP)characteristics were not obvious,and no photosynthetic oxygen evolution could be detected.With the increase of silicon concentrations(2®8 mg·L^(−1)),the cell density,the specific growth rate and the maximum standing biomass all increased significantly.In silicon concentration of 2 mg·L^(−1)group,the concentration of chlorophyll a and carotenoid per unit cell were significantly lower than the other three silicon concentration groups(P<0.05).There was no significant difference in the contents of chlorophyll a and carotenoid per unit cell,F_(v)/F_(m)or the photosynthetic oxygen evolution rate among silicon concentration groups of 4 mg·L^(−1),6 mg·L^(−1)and 8 mg·L^(−1).It was concluded that the silicon was the limiting factor for the rapid proliferation of diatom.The concentration of silicon in the middle channel of the South-to-North Water Diversion Project was relatively high(about 5 mg·L^(−1)),meeting the needs of diatom proliferation,which was an important factor leading to the rapid proliferation and dominance of diatom.

关 键 词：南水北调 硅藻 快速增殖 硅浓度 

分 类 号：Q178.11[生物学—水生生物学]