海口市红城湖浮游植物群落结构特征分析

为了解海口红城湖浮游植物的群落结构特征,调查研究了2016年11月、2017年3月和2017年7月浮游植物群落结构和水质因子。结果表明,3次样品采集中共鉴定浮游植物种类141种(含变种和变型),隶属于7门56属,其中绿藻门的种类最丰富为60种,其次为裸藻门、硅藻门和蓝藻门,分别为35种、22种和15种,隐藻门为6种,甲藻门2种,金藻门1种。浮游植物细胞密度呈现先降低后升高的趋势,2016年11月浮游植物细胞密度为(1.12±0.49)×10^8cells/L,2017年3月浮游植物细胞密度为(4.43±2.31)×10^7cells/L,2017年7月浮游植物细胞密度为(8.57±8.83)×10^8cells/L。从浮游植物密度组成来看,2016年11月浮游植物细胞密度以绿藻门和蓝藻门为主,分别占43.68%、27.87%;其次为隐藻门和硅藻门,分别占12.07%、10.38%。2017年3月浮游植物细胞密度以绿藻门为主,占88.78%;2017年7月浮游植物细胞密度以绿藻门为主,占98.22%。浮游植物优势种呈现一定的时间变化,在2016年11月为蓝藻门的细小平裂藻Merismopedia tenuissima,硅藻门的梅尼小环藻Cyclotella meneghiniana,隐藻门的尖尾蓝隐藻Chroomonas acuta、啮蚀隐藻Cryptomons erosa,绿藻门的球衣藻Chlamydomonas globosa;2017年3月为雷氏衣藻Chlamydomonas reinhardtii,硅藻门的梅尼小环藻Cyclotella meneghiniana,隐藻门的尖尾蓝隐藻Chroomonas acuta;2017年7月为蓝藻门的细小平裂藻Merismopedia tenuissima,硅藻门的梅尼小环藻Cyclotella meneghiniana,绿藻门的丛球韦斯藻Westella botryoides。NMDS排序显示,水体中TN、TP和电导率是影响红城湖浮游植物群落结构的主要因子。

Phytoplankton community structure of Hongcheng Lake in Haikou City,Hainan

The paper is inclined to make an investigation of the phytoplankton community structure of Hongcheng Lake in Haikou,including the speices composition,the population size distribution,and their dominant species for the purpose to evaluate the indexical status-in-situ of the aquatic ecosystems. And,for the said purpose,we have made an investigation of the phytoplankton community structure of the lake and collected the sampling formulation of the phytoplankton and water quality factors in the lake in Nov.,2016;March,2017;and,July,2017,so as to identify and clarify the correlation between the phytoplankton and the water quality factors. The results of our investigation indicate that the following 4 points.( 1) We have found and identified 141 species( including varieties and genera) of phytoplankton,which belong to 56 genera under the 7 divisions in the said lake based on the samples in Nov. 2016,March,2017 and July,2017,the most abundant divisions,among which there exist60 species of chlorophyta. They can further be divided into 35 species of euglenophyta. Among the 35 species,22 species are of bacillariophyta and 15 species are of cyanophyta,as well as 6 species are of cryptophyta,with 2 species being dinophyta and 1 being of chrysophyta.( 2) The cell density of phytoplankton has also been found increasing first and then declining in our study period in the Hongcheng Lake. The average cell density of phytoplankton has been accounted for( 1. 12 ± 0. 49) × 10^8 cells/L in Nov.,2016,whose chlorophyta and cyanophyta have been found contributing to 43. 68% and 27. 87% of the total cell density,respectively, which are followed by bacillariophyta and cryptophyta, whose conributions are at about 12. 07% and10. 38% of the total. Moreover,the average size of phytoplankton cell density has to be statistically equal to( 4. 43 ± 2. 31) ×10^7 cells/L at the time of March,2017,of which chlorophyta turns out to be contributed to 88. 78% of the total cell densities.And,meanwhile,the average phytoplankton cell density should occupy( 8. 57 ± 8. 83) × 10^8 cells/L in July,2017,whose chlorophyta should occupy 98. 22% of the total cell densities.( 3)The dominant species of the phytoplankton have been found various with the change of seasons in the said lake. For example,there have been found Merismopedia tenuissima,Cyclotella meneghiniana,Chroomonas acuta,Cryptomons erosa,Chlamydomonas globos in Nov.,2016,whareas the Chlamydomonas reinhardtii,Cyclotella meneghiniana,and Chroomonas acuta have been discovered in March,2017. In addition,Merismopedia tenuissima, Cyclotella meneghiniana, Westella botryoides have been found in July,2017.( 4) Furthermore,NMDS analysis suggests that the total nitrogen( TN),the total phosphorus( TP)and their conductivity have all been found to be the major driving factors that tend to influence the change of phytoplankton community structure in the above said lake.