在尼罗河中研究了原生动物群落与环境变量之间的关系,以评估其作为水质指标的潜力。在一年的周期(2016年2月至2017年1月)中,在尼罗河Damietta分支的六个采样点每月对原生动物进行采样,整个环境条件的空间梯度。原生动物群落由54种组成,属于六个主要的异养原生动物门。丰度(平均,1089±576.18个体L-1)和生物量(平均值,86.60±106.13μgL-1)在位点之间具有可比性。纤毛虫占原生动物物种丰富度的大多数(30种),丰度(79.72%),和生物量(82.90%)。聚类分析导致原生动物物种分为三组,最主要的物种是杂食性纤毛虫类。铝,氟化物,浊度对丰度和生物量产生负面影响,而溶解氧和钾对生物量有积极影响。在研究区记录的优势物种中,变形虫与径流变量相关,而细菌纤毛虫Colpidiumcolpoda,青光眼闪烁,和雷公藤与异养细菌的丰度有关,浮游植物生物量,和总有机碳。总溶解盐,PO4、NH3、NO2、溶解氧、和总有机碳是原生动物分布的最强致病因子。与其他地点相比,VI地点的α-Mesosaprophic环境证实了农业径流的高负荷。这项研究表明,原生动物可以成为该亚热带淡水河流系统水质状况的潜在生物指标。
The relationship between the protozoan communities and environmental variables was studied in the Nile River to evaluate their potential as water quality indicators. Protozoans were sampled monthly at six sampling sites in the Nile\'s Damietta Branch across a spatial gradient of environmental conditions during a 1-year cycle (February 2016-January 2017). The
Protozoa community was comprised of 54 species belonging to six main heterotrophic
Protozoa phyla. The abundance (average, 1089 ± 576.18 individuals L-1) and biomass (average, 86.60 ± 106.13 μg L-1) were comparable between sites. Ciliates comprised the majority of protozoan species richness (30 species), abundance (79.72%), and biomass (82.90%). Cluster analysis resulted in the distribution of protozoan species into three groups, with the most dominant species being the omnivorous ciliate Paradileptus elephantinus. Aluminium, fluoride, and turbidity negatively affected abundance and biomass, while dissolved oxygen and potassium positively impacted biomass. Of the dominant species recorded over the study area, the amoebozoa Centropyxis aculeata was associated with runoff variables, while the bacterivorous ciliates Colpidium colpoda, Glaucoma scintillans, and Vorticella convallaria were related to the abundance of heterotrophic bacteria, phytoplankton biomass, and total organic carbon. Total dissolved salts, PO4, NH3, NO2, dissolved oxygen, and total organic carbon were the strongest causative factors for
protozoa distribution. The α-Mesosaprobic environment at site VI confirmed a high load of agricultural runoffs compared to other sites. This study demonstrates that protozoans can be a potential bioindicator of water quality status in this subtropical freshwater river system.