不同营养状态下附生藻类对菹草(Potamogeton crispus)叶片光合机能的影响  

The effect of epiphytic algae on the photosynthetic function of Potamogeton crispus in different nutrition conditions

作　　者：陈灿[1] 张浏[1] 赵兴青[1] 虞斌[1] 尹大强[1] 

机构地区：[1]污染控制与资源化研究国家重点实验室南京大学环境学院,南京210093

出　　处：《湖泊科学》2007年第4期485-491,共7页Journal of Lake Sciences

基　　金：国家"973"项目(2002CB412307);江苏省自然科学基金(BK2005082)联合资助.

摘　　要：以沉水植物——菹草为对象,实验室模拟水下弱光(100±10μmole/(m^2·s)环境,进行附生藻类(生物控制和无生物控制)和营养(中营养、富营养和超富营养)双因子正交实验,探讨富营养水体附生藻类暴发对沉水植物叶片光合机能的影响．结果表明,水体营养水平提高促使菹草叶片附生藻类大量繁殖,富营养条件(TN:1mg/L;TP:0．1mg/L)下附生藻类在菹草叶片的增殖速率(Chl．a)达到0．16μg/(cm^2·d)．日本沼虾+耳萝卜螺的生物控制模式能有效控制菹草叶片上附生藻类的生物量．水下原位叶绿素荧光参数观测表明,42 d附生藻类引起菹草叶片光合机能下降,Chl．a密度下降25．2%,caro密度下降20．8%,PSⅡ电子产率降低9．8%,电子传递速率(ETR)下降,光化学淬灭(qP)平均下降超过60%．研究表明,水体营养水平提高促进沉水植物叶片附生藻类增殖,导致菹草光合机能下降,营养盐的作用是间接的．Direct evidence of epiphytic algal effects on the photosynthetic function of submerged macrophytes is scarce. To obtain more reliable, quantitative data about this phenomenon, a laboratory experiment was carried out over 42 days in controlled conditions with the submerged maerophyte, Potamogeton cripus. It was based on a 2×3 factorial design with two epiphytie conditions （with bioeontrol and without） and three nutrition levels （mesotrophie, eutrophic, hypertrophic）, to study on the epiphytie algae booming and the effect of epiphytie algae on the photosynthetic function of P. cripus in different nutrition levels. The result showed that enhanced availability of major nutritional elements like N and P promoted epiphytie algae booming growing, and with a production velocity of 0. 16 Chl. a μg/cm^2d on leaves surface under eutrophic conditions （TN： lmg/L; TP： 0. lmg/L）. However, the boom- ing growth of epiphytie algae was obstructed by bioeontrol with Macrobrachium nipponense ＋ Radiuauricularia, even in eutrophic conditions. Original position survey of leaves＇ chlorophyll fluorescence parameters showed as follows. Epiphytie algae booming growing on leaves surfaces for 42 days resulted in leaves＇ ehlorophyll-a density declining by 25.2%, carotenoid density declining by 20. 8%, effective quantum yield of PSII declining by 9.8%, electron transport rate （ETR） declining steadily, and photochemical quenching （qP） declining more than 60%. It can be concluded that the booming of epiphytie algae might have affected the growth of P. crispus, by altering the leaf density segments and photosynthetic function of P. crispus

关 键 词：附生藻类 荧光参数 光合机能 菹草 

分 类 号：Q945[生物学—植物学]