海洋围隔生态系中赤潮发生前后浮游植物群落结构的初步分析

PRELIMINARY ANALYSIS FOR THE STRUCTURES OF PHYTOPLANKTON COMMUNITY IN A MARINE ENCLOSED ECOSYSTEM BEFORE AND AFTER A RED TIDE PROCESS

1990年5至7月,在国家海洋局第三海洋研究所陆基水池中进行了了围隔生态系内富营养化引起的生态效应实验。实验表明,富营养的围隔袋中,浮游植物群落结构逐渐发生了变化,组成和数量都有很大的变动。形成水华和赤潮。并发生了种群的演替。水华以硅藻开始,形成高潮之后便衰退。随后微鞭毛藻和甲藻开始较大量繁殖。金藻和甲藻在实验中形成赤潮,最高值达到6.7×10^(10)cells/m^3。甲藻和硅藻的生长似乎互相抑制。实验初期,在硅藻繁盛时,甲藻的种、属和数量都很少。而在演替的后期,硅藻衰落时,甲藻占优势。数量最高达2.6×10~8cells/m^3。实验演示了发生在硅藻水华之后的甲藻赤潮发展过程,与1986年厦门西海域发生的裸甲藻赤潮的发展过程相似。实验结果为进一步研究甲藻赤潮的形成规律及其预测预报积累了资料和经验。

A reseach experiment on ecological effects causeed by eutrophication in an enclosure ecosystem was set up in a land-based tank at the Third Insitute of Oceanography, SOA. from May to July in 1990. The results show.In the eutrophic enclosure bag, the phytoplankton community structure gradually changed in its composition and numbers of species, resulting in phytoplankton bloom and population succession.Bloom started with diatom. Microflagell-ate and Dinoflagellates began to grow in great quantity at the end of diatom bloom. Chrysophyta and dinoflagellate dominated in the bloom during the experiment with a maximum of 6.7× 1010cells/m3. It was probably that the growth of diatom and dinoflagellate were restrained from each other. In the beginning of experiment,dinoflagellate species and numbers were depressed during diatom bloom. After diatom declined, dinoflagellate dominated in the last stage of the succession,with a maximum of 2.6 × 108cells/m3. The experiment showed a case of Red Tide development which dinoflagellate Red Tide followed diatom bloom. The process was similar to Gymnodinium Red Tide occuring in Xiamen Bay in 1986. The results of experiment may be taken as the references in Red Tide forecast and research.