Algal community and pollution indicators for the assessment of water quality of Ismailia canal, Egypt

摘要

The phytoplankton community structure is affected by both ecological and spatial factors. Influences of these two factors on phytoplankton are still poorly understood. Here, the relative effects of spatio-temporal variations on the structuring and community of phytoplankton were examined in eight sites along Ismailia canal during wet winter and dry summer seasons, 2018. A total of 58 taxa were identified, belonging to five taxonomical groups, phytoplankton had an abundance ranging from 56,906 ind. L-1 in winter to 122,418 ind. L-1 in summer. Bacillariophyta was the leading and most dominant phyla representing about 45% of the total number of individuals owing to the great flourishing of Synedra ulna, Cyclotella kutzingiana, Cyclotella meneghiniana throughout the year. Spatially, sites 1, 2 and 7 showed the highest phytoplankton abundance, whereas site 6 showed the lowest community. Pearson correlation and Canonical correspondence analysis indicated that nitrate had a positive correlation with the phytoplankton community, however TDS showed a negative correlation with the algal community and silicate showed a positive correlation with Bacillariophyta. High relative Palmer's Index scores were recorded in most of the sampling sites ranged from 13 to 21 particularly during summer, that coincides with Shannon-Weiner index results which indicating Ismailia canal suffers from organic pollution in most of the sampling sites.