This study aimed at monitoring and management of the surface water and potentially pathogenic microbes of Lake Tonga (Algeria) with respect to. It characterized the main bacterial diversity patterns of Lake Tonga and predicted from water physicochemical parameters and water quality index (WQI) the distribution of bacterial species and the main indicator groups of faecal water contamination. Water samples were taken monthly at three sampling sites of different water depths. Several physicochemical parameters were measured; of which some were included in computing WQI to characterize the water quality of the lake. Counting, isolation and bacterial identification methods were used to characterize the existing aerobic heterotrophic bacteria. The composition of the microbial community of the waterbody of Lake Tonga included an abundant culturable bacterial flora belonging to several bacterial families and whose specific richness varied between water depths of the sites sampled. Species richness of the bacteria identified phenotypically varied between 7 and 11 per sample. The site with shallow water was the richest in bacterial species, compared to moderate and deep waters. The redundancy analysis showed the main physicochemical drivers of the microbial community composition. Our findings showed that high WQI scores indicated the water quality deterioration which triggered the increase in total load of faecal indicator bacterial groups. This study identified in Lake Tonga an important culturable aerobic bacterial flora whose specific richness and distribution varied spatially following the effects of water physicochemical parameters. Lake Tonga needs an integrated management plan to mitigate human disturbances declining water quality.

本研究旨在监测和管理汤加湖（阿尔及利亚）的地表水和潜在致病微生物。表征了汤加湖主要细菌多样性模式，并从水理化参数和水质指数（WQI）预测了细菌种类分布和粪便水污染的主要指标组。每月在不同水深的三个采样点采集水样。测量了几个物理化学参数；其中一些被包含在计算 WQI 中以表征湖泊的水质。采用计数、分离和细菌鉴定方法对现有好氧异养细菌进行了表征。汤加湖水体微生物群落的组成包括丰富的可培养细菌菌群，属于多个细菌科，其具体丰富度因采样地点的水深而异。每个样本的表型鉴定细菌的物种丰富度在 7 到 11 种之间变化。与中水和深水区相比，浅水区细菌种类最丰富。冗余分析显示了微生物群落组成的主要物理化学驱动因素。我们的研究结果表明，高 WQI 分数表明水质恶化，从而引发了粪便指示菌群总负荷的增加。这项研究在汤加湖中发现了一种重要的可培养需氧细菌菌群，其具体丰富度和分布随着水理化参数的影响而在空间上发生变化。汤加湖需要一个综合管理计划来减轻人为干扰导致的水质下降。