Assessing phytoplankton populations and their relation to water parameters as early alerts and biological indicators of the aquatic pollution

Abstract

Biological water quality is one of the main indicators of water pollution. The main objective of the current study was to assess El-Temsah Lake, Egypt, water quality in 2018 using phytoplankton and physicochemical indices (e.g. species richness, diversity, equitability, and Palmer indices). Spatio-seasonal variability of phytoplanktons, qualitative status and physiochemical parameters assessed in 20 sample sites of El-Temsah Lake during the winter and summer seasons of 2018. Our results indicated that the phytoplankton abundance comprised of 105 species from 69 genera in summer and 101 species from 68 genera in winter. Navicula cryptocephala Kützing was the predominant species in both seasons, especially in the middle sites of the lake. Phytoplankton quantity negatively relates to pH, temperature, and total dissolved solids but is positively related to nitrate and silicate level according to the Pearson correlation coefficient analysis. Summer season recorded higher diversity, richness, and equitability indices than winter. According to the Shannon diversity and Margalef indices, El-Temsah Lake was in moderate pollution levels. In conclusion, Genus Palmer's Index values at the north sites were in the range of 20 during the summer, implying a high probability of organic pollution of these sites. Thus, immediate action is required instantly to retrieve a good quality of El-Temsah Lake's aquatic ecosystem. The findings of this research offered a reference for analyzing the composition and distribution of phytoplankton communities, nutrient status, and pollution levels in El-Temsah Lake, as well as in other comparable lakes.

Keywords

• Phytoplankton abundance
• Diversity index
• Physicochemical parameters
• El-Temsah Lake
• Palmer's Index