Belokda Wafae, Khalil Karima, Loudiki Mohamed, Aziz Faissal, Elkalay Khalid
Laboratory of Applied Sciences for the Environment and Sustainable Development School of Technology Essaouira, Cadi Ayyad University, Essaouira Al Jadida, Route d'Agadir, BP 383, Essaouira, Morocco.
Laboratory of Algology and Hydrophytes. Faculty of Sciences Semlalia of Marrakech, Cadi Ayad University, Bd. Prince Mlly Abdellah, B.P. 511, Marrakech, Morocco.
Saudi J Biol Sci. 2019 Mar;26(3):431-438. doi: 10.1016/j.sjbs.2017.11.047. Epub 2017 Nov 26.
In order to find effective measures to control a Moroccan shallow reservoir (Sidi Abderrahmane), a better understanding of phytoplankton composition, abundance, spatial and temporal distribution it is necessary. Trophic level and the stability status were assessed upon the basis of Shannon diversity index (H'), species richness (S), and evenness (J) index. Statistical tests were used to evaluate the different relationships between phytoplankton and the concentrations of several physico-chemical parameters, and the main soluble nutrients. In surveys, the samples were taken fortnightly from May 2011 to December 2012. 64 taxa belonging to seven groups of phytoplankton were identified, including Bacillariophyceae (25 taxa), Chlorophyceae (22 taxa), and Cyanophyceae (9 taxa). and were the main contributors to the dissimilarity in temporal distribution. Phytoplankton population never reached a monospecificity situation. Shannon and evenness indices were between (0.0001 < H' < 0.15; 0.003 < J < 0.085) and manifested a young phytoplankton community with high multiplying power. There were significant correlations between total phytoplankton (r = 0.015, p < .01) and water temperature. Significant negative correlations were observed between transparency and Cyanophyceae (r = -0.208, p < .05) and between the number of species and transparency (r = -0.206, p < .05), orthophosphorus (r = -0.377, p < .01), and nitrates (r = -0.301, p < .01). A negative correlation was found between Orthophosphorus and Chlorophyceae (r = -0.377, p < .01). Similar correlations were also observed with nitrates and Chlorophyceae (r = -0.297, < .01), Silica and Bacillariophyceae (r = 0, < .01) and total phytoplankton (r = -0.372, < .07). The underwater light condition, as indicated by Secchi depth fluctuations, hydraulic process conditions (short residence time, short outflow/inflow ratio) were shown to be the limiting factors in regulating the density of phytoplankton. With reference to Palmer pollution index, test results indicated an oligotrophic or mesotrophic reservoir. The data presented provide the first contemporary account of the level of algal diversity present, the prominent environmental conditions and trophic status of Sidi Abderrahmane reservoir waters.
为了找到控制摩洛哥一座浅水水库（西迪·阿卜杜勒拉赫曼水库）的有效措施，有必要更好地了解浮游植物的组成、丰度、空间和时间分布。基于香农多样性指数（H'）、物种丰富度（S）和均匀度（J）指数评估了营养水平和稳定性状况。使用统计测试来评估浮游植物与几种理化参数浓度以及主要可溶性养分之间的不同关系。在调查中，于2011年5月至2012年12月每两周采集一次样本。共鉴定出属于七组浮游植物的64个分类单元，包括硅藻门（25个分类单元）、绿藻门（22个分类单元）和蓝藻门（9个分类单元）。 和 是造成时间分布差异的主要因素。浮游植物种群从未达到单种情况。香农指数和均匀度指数介于（0.0001＜H'＜0.15；0.003＜J＜0.085）之间，表明是一个具有高繁殖力的年轻浮游植物群落。总浮游植物与水温之间存在显著相关性（r = 0.015，p＜0.01）。透明度与蓝藻门之间（r = -0.208，p＜0.05）以及物种数量与透明度之间（r = -0.206，p＜0.05）、与正磷酸盐（r = -0.377，p＜0.01）和硝酸盐（r = -0.301，p＜0.01）之间均观察到显著负相关。正磷酸盐与绿藻门之间存在负相关（r = -0.377，p＜0.01）。在硝酸盐与绿藻门（r = -0.297，p＜0.01）、二氧化硅与硅藻门（r = 0，p＜0.01）以及总浮游植物之间（r = -0.372，p＜0.07）也观察到类似的相关性。如塞氏深度波动所示的水下光照条件、水力过程条件（短停留时间、短流出/流入比）被证明是调节浮游植物密度的限制因素。参照帕尔默污染指数，测试结果表明该水库为贫营养或中营养型。所呈现的数据首次提供了西迪·阿卜杜勒拉赫曼水库水域当前藻类多样性水平、突出环境条件和营养状况的说明。
