Lelong P P, Bianchi M A, Martin Y P
Can J Microbiol. 1980 Mar;26(3):297-307.
During the spring, an experiment was conducted on the production of natural phytoplankton in a continuous flow layout of large capacity, and an analysis was made of the simultaneous evolution of microplanktonic populations (taxonomic composition, diversity, class ranges, and energetic charge) and of bacterial populations (structure, diversity, dominances, and cetabolic potentialities). Oligotrophic initial conditions were charcterized by a poor (0.22 umg of chlorphyll a/L) and diversified (pigment diversity = 4.5) phytoplankton with nanoplanktonic dominance associated with several benthic type diatoms. Bacterial flora, in which pseudomonads were dominant (54.5%), were also diversified (Shannon index H = 3.57). Metabolic potentialities of these bacterial communities were several. Enrichment of the milieu caused the selection and development of a small number of algal species dominated by the diatoms skeletonema costatum (64 x 106/L) and Chaetoceros (3.2 x 106/L) leading to a paucispecific population with a large biomass, a pigment diversity of 1.97, and a chlorophyll a concentration of 25.08 mu/L. The bacterial community then because diversified (H = 4.12) and, although pseudomonads remained dominant (62%), a larger use of organic micromolecules was noted. The establishment of this phytoplanktonic community was followed by a zooplanktonic development in which larger species succeeded smaller ones (ciliates, tintinnides, rotifers, and copepods) corresponding to the global increase of the phytobiomass. Although this system appeared to be in a phase of relative stability, a decease in the energetic charge showed a disturbance in the physiological state of the planktonic populations. These phenomena led to the vanishing of the diatom's dominance (Chaetoceros, and then S. costatum) and its replacement by nanoplankton (123 x 106 cells/L) and dinoflagellates (300000 cells/L). A modification in the organic wealth of the milieu with the addition of particular complex material that was not or little degraded caused deep disturbances in the bacterial populations. Their diversity reached a very low level (H = 1.56 to 2.25) with a proliferation of vibrions (up to 74%) well equipped with exoenzymes, but more restricted in their nutritional versatility (marked preference for organic macromolecules). During the final phase of experimentation, despite a change in qualitative composition and a more important biomass, microplanktonic and bacterial populations returned to a diversified state nearing that of the initial conditions (pigment diversity = 3.2; H = 3.37).
春季期间，在大容量连续流动布局中进行了天然浮游植物生产实验，并对微型浮游生物种群（分类组成、多样性、类群范围和能量电荷）以及细菌种群（结构、多样性、优势度和代谢潜力）的同步演变进行了分析。贫营养初始条件的特征是浮游植物数量少（叶绿素a含量为0.22微克/升）且种类多样（色素多样性=4.5），以微型浮游生物为主，伴有几种底栖型硅藻。细菌菌群中假单胞菌占主导地位（54.5%），种类也多样（香农指数H=3.57）。这些细菌群落具有多种代谢潜力。环境的富集导致少数藻类物种的选择和发展，以中肋骨条藻（64×10⁶/升）和角毛藻（3.2×10⁶/升）为主导，形成了一个生物量较大、色素多样性为1.97且叶绿素a浓度为25.08微克/升的寡种种群。随后细菌群落变得多样化（H=4.12），尽管假单胞菌仍然占主导地位（62%），但对有机小分子的利用增加。这种浮游植物群落形成后，浮游动物开始发展，大型物种取代了小型物种（纤毛虫、铃虫、轮虫和桡足类），这与浮游植物生物量的总体增加相对应。尽管这个系统似乎处于相对稳定阶段，但能量电荷的下降表明浮游生物种群的生理状态受到了干扰。这些现象导致硅藻的优势地位消失（先是角毛藻，然后是中肋骨条藻），被微型浮游生物（123×10⁶个细胞/升）和甲藻（300000个细胞/升）取代。向环境中添加未降解或很少降解的特定复杂物质，改变了环境的有机物质含量，对细菌种群造成了严重干扰。它们的多样性降至极低水平（H=1.56至2.25），弧菌大量繁殖（高达74%），这些弧菌配备了丰富的外切酶，但营养多样性更受限（对有机大分子有明显偏好）。在实验的最后阶段，尽管定性组成发生了变化且生物量更大，但微型浮游生物和细菌种群恢复到了接近初始条件的多样化状态（色素多样性=3.2；H=3.37）。
