绿藻门浮游植物对低浓度营养盐的耐受性  

The tolerance of chlorophyta phytoplankton to low concentrations of nutrients

作　　者：王小冬[1,2] 刘兴国[1] 朱浩[1] 车轩[1] 顾兆俊[1] 田昌凤[1] 李月[1] 

机构地区：[1]中国水产科学研究院渔业机械仪器研究所,农业部渔业装备与工程技术重点实验室,上海200092 [2]中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室,南京210008

出　　处：《渔业现代化》2012年第5期21-26,共6页Fishery Modernization

基　　金：湖泊与环境国家重点实验室开放基金(2010SKL006);公益性行业(农业)科研专项(201203083)

摘　　要：假设蓝藻水华的形成与蓝藻门植物能够耐受低浓度营养盐有关,为了验证是否只有蓝藻门浮游植物才能够耐受低浓度的营养盐,选用绿藻门的纤维藻属(Ankistrodesmus)占绝对优势的天然水体在不添加外源营养盐的温室条件下进行试验。试验持续了18 d。试验期间在8:30、14:00时平均水温分别为31.6℃、34.6℃。试验水体总氮、总磷、溶解性总氮、溶解性总磷、活性磷浓度的变化范围依次为0.7～1.5、0.03～0.09、0.45～0.70、0.02～0.05、0～0.022 mg/L;试验初始的叶绿素a含量约为190μg/L,结束时降低至30μg/L左右。试验期间一直维持绿藻门的纤维藻属优势。结果表明,在没有添加外源营养盐时,绿藻门浮游植物也能够耐受低浓度的营养盐,天然水体中蓝藻水华的发生与蓝藻能够耐受低浓度氮磷营养盐没有必然联系;同时推断:绿藻在初始占优势时,在低营养盐条件及环境条件没有特别变化时,蓝藻不可能逆转成为优势种。The formation of cyanobacteria bloom was considered to be related to their tolerance of low concen- trations of nutrients on the basis of the previous experiment result. In order to verify the hypothesis that cya- nobacteria can tolerate low concentrations of nutrients alone, natural water of Ankistrodesmus （Chlorophyta） dominance was studied in greenhouse without added nutrients for 18 d. The mean water temperature at 08：30 a.m. and 14：00 p.m. of the experiment was 31.6℃ and 34.6℃, respectively. The ranges of concentrations of total nitrogen, total phosphorus, dissolved total nitrogen, dissolved total phosphorus and soluble reactive phosphorus were 0.7-1.5, 0.03-0.09, 0.45-0.70, 0.02-0.05 and 0-0.022 mg/L, respectively. The initial chlorophyll a concentration was about 190 I^g/L, and that at the end of the experiment reduced to about 30 txg/L. Ankistrodesmus（Chlorophyta） maiotained dominance throughout all the experiment. It showed Chloro- phyta could tolerate low concentrations of nutrients when there was no external nutrients addition. Thus, there was not inevitable relationship between the formation of cyanobacteria bloom and their tolerance of low concen- trations of nutrients. Further deduction ： initial Chlorophyta with low concentrations of nutrients and no specific changes dominance can＇t turn to cyanobacteria dominance of the environment.

关 键 词：绿藻门 蓝藻门 营养盐 耐受性 

分 类 号：Q178.1[生物学—水生生物学]