Shymaa S. Zaher

Abstracts

2 Phytoplankton Diversity and Abundance in Burullus Lagoon, Southern Mediterranean Coast, Egypt

Authors: Shymaa S. Zaher, Hesham M. Abd El-Fatah, Dina M. Ali

Abstract:

Burullus Lagoon is the second largest lake, along the Mediterranean seashore. It exposed to over nutrient enrichment from fish farming and agricultural drainage wastes. This study assesses the present status phytoplankton response to different flow events, including domestic, agricultural, industrial, and fish farms discharge in the three main sectors of Burullus Lagoon, to focus on the influence of environmental variables on phytoplankton species composition inhabiting the Lagoon. Twelve sites representing the eastern, central, and western basin were selected during winter and summer 2018. Among the most abundant group, Chlorophyceae came in the first rank by 37.9% of the total phytoplankton densities, Bacillariophyceae (29.31%), Cyanophyceae (20.7%), Euglenophyceae (8.63%) and Dinophyceae (3.4%). Cyclotella menenghiana was the most abundant diatoms, while Scenedesmus quadricauda, S. acuminatus, and S. bijuga were highly recorded nearby the drains (in the middle sector). Phytoplankton in Burullus Lagoon attained the lowest values during the winter season and the highest ones during the summer season. The total count of phytoplankton in the middle and western basin of the lake was higher than that of the eastern part. Excessive use of chemical fertilizers, pesticides, and washing out of nutrients loaded to the drainage water, leading to a significant pronounced decrease in community composition and standing crop of phytoplankton in Burullus Lake from year to year, hold the danger of shifting the lagoon ecosystem.

Keywords: Water pollution, phytoplankton, environmental variables, Burullus Lagoon

Procedia PDF Downloads 1
1 Impact of Flood on Phytoplankton Biochemical Composition in Subtropical Reservoir, Lake Nasser

Authors: Shymaa S. Zaher, Howayda Abd El-Hady, Nehad Khalifa

Abstract:

Lake Nasser is vital to Egypt as it is the main Nile water reservoir. One of the major challenges in ecological flood is to establish how environmental enrichment in nutrients availability may affect both the biochemical composition of phytoplankton and the species communities. Samples were collected from twenty sites representing different lake sectors along the main channel of the lake during 2017. Generally, phytoplankton distribution during flood season in Lake Nasser indicates the predominance of Cyanophyceae at all lake sectors. Increases in NO₂ (9.31 µg/l) and PO₄ (7.11µg/l) at the Abu-Simble sector are associated with changes in community structure and biochemical composition of phytoplankton, where Cyanophyceae blooming occur associated with retardation in biopolymeric particulate organic carbon. The maximum total biochemical contents (91.29 mg/l) and biopolymeric particulate organic carbon (37.15 mg/l) was found at El-Madiq sector where there was optimum nutrients (NO₂ 0.479 µg/l and PO₄ 5.149µg/l), a highly positive correlation was found between Cyanophyceae and NO₂ in the lake (r = 0.956). A highly positive correlation was detected between carbohydrates and both transparency and pH in the lake (r = 0.974 and 0.787). Also carbohydrates had a positive relation with Bacillariophyceae (r = 0.610). Flood positively alter the water quality of the lake by increasing dissolved oxygen and nutrients enrichment to the aquatic ecosystem, affecting other aquatic organisms of higher trophic levels as economic fishes inhabiting the lake.

Keywords: biochemical composition, fresh water, aquatic microalgae, Aswan high dam lake

Procedia PDF Downloads 1