里下河腹地典型水体秋季浮游植物生态学特征

Phytoplankton ecological characteristics in the typical water bodies of Lixia River hinterland in autumn

采用浮游植物种类相似性指数、Pielou均匀度指数、Mcnaughton优势度指数、香农-威纳多样性指数,研究了2014年秋季里下河腹地典型水体中浮游植物的生态学特征,以期为里下河腹地典型水体的生态环境评价和综合整治提供一定科学依据。结果表明：里下河腹地典型水体共出现浮游植物7门81种;其中绿藻种数最多,共40种,占浮游植物总种数的49.4%;硅藻次之,共14种,占浮游植物总种数的17.3%;其余各门藻类数量由多到少依次为蓝藻、裸藻、黄藻、隐藻、甲藻,种类数量分别为13,6,4,3,1,占浮游植物总种数的百分比分别为16.1%,7.4%,4.9%,3.7%,1.2%。各监测点的浮游植物种类组成均以绿藻、蓝藻、硅藻为主,浮游植物种类数变化在13～37之间,生物量变化在（1.20～14.05）×106ind·L-1之间。各站位间的浮游植物相似性指数变化在0.07～0.50之间,相似性较低,显示出各个监测点的生境差异较大。共发现优势种4门19种,优势度变化在0.10～0.60之间,除了大纵湖和泰东河口的铜绿微囊藻以及兴化二水厂的水华微囊藻具有较高优势度外,其余各站位的优势种优势度都不高。浮游植物多样性指数变化在2.07～4.45之间,平均为3.29;均匀度指数变化在0.51～0.87之间,平均为0.76;浮游植物多样性指数和均匀度指数总体较高。

In order to provide the scientific data for the eco-environment evaluation and comprehensive improvement of water bodies in Lixia River hinterland,the Jaccard species similarity index,Pielou uniformity index,Mcnaughton predominant index,Shannon-Wiener diversity index were used to study the phytoplankton ecological characteristics ofthe typical water bodies in Lixia River hinterland in autumn of 2014. The results showed that 7 classes including81 species of phytoplankton had been found in Lixia River hinterland. Among them,Chlorophyta,40 species,predominated in species,accounting for 49. 4% of the total phytoplankton species,Bacillariophyta,14 species,taken the second place,accounting for 17. 3% of the total phytoplankton species. And the species number of Cyanophyta,Euglenophyta,Xanthophyta,Cryptophyta,Pyrrophyta were 13,6,4,3,1,respectively,accounting for 16. 1%,7. 4%,4. 9%,3. 7%,1. 2% of the total phytoplankton species,respectively. The species number and biomass of phytoplankton in Lixia River hinterland in autumn of 2014 ranged from 13 to 37 and 1. 20 × 106ind·L- 1to 14. 05 ×106ind·L- 1,respectively. Chlorophyta,Cyanophyta,Bacillariophyta predominated both in species number and biomass. The analysis results of similarity showed that the similarity index ranged from 0. 07 to 0. 50,which meant the similarity indexes were very low and the eco-environment differed significantly from station to station. The analysis result of predominance index showed that there were 4 phyla 19 predominant species in Lixia River hinterland in autumn of 2014,and the predominant indexes were not high（ except the high predominant indexes at Dazhong Lake with Microcystis aeruginisa of 0. 46,Taidong estuary with Microcystis aeruginisa of 0. 60 and the second waterworks of Xinghua with Microcystis flos-aquae Kirchn of 0. 51）,ranging from 0. 10 to 0. 60. The analysis results of diversity and uniformity showed that the diversity index and uniformity index ranged from 2. 07 to 4. 45 and 0. 51 to 0. 86,respectively,whose average values were 3. 29 and 0. 76,which meant that both diversity and uniformity of phytoplankton were good.