Lake Idku suffers from pollution from different sources; either agricultural or municipal wastes. It faces tremendous ecological stresses due to the environmental changes and threats originated from discharges of drains. So, the aim of the present study is to assess its pollution status according to the phytoplankton species distribution and water quality index. Eight water samples were collected from the lake, preserved and analyzed. The highest total count of phytoplankton was 1,865,000 unit L-1 is at station 4 (at the southern part of the lake), while the lowest was in front of El-Boughaz. Phytoplankton species were belonging to four divisions namely; Euglenophyceae, Chlorophyceae, Bacillariophyceae and Cyanophyceae. The most abundant genera located at the highly polluted zones were Euglena spp. and Phacus spp.; at stations 4 and 7 (in front of El-Khairy drain); this is mainly due to drain wastes. Scenedesmus spp. (Chlorophytes), Cyctotella spp. and Nitzchia spp. (Bacillariophyceae), Microcystis spp. and Chroococcus spp. were the most dominant at these stations, which are characterized by high levels of pollution. Members of euglenoids (Phacus spp. and Euglena spp.) were the most indicators to the pollution especially at stations 4 and 7 nearby drains, where they represented the main components of the total count of phytoplankton and characterized by high levels of ammonia and organic carbon. This was confirmed from the correlation matrix between phytoplankton with phosphate and ammonia. The national sanitation foundation water quality index (NSF-WQI) gives an indication to medium water quality status in lake Idku and refers to low value nearby El-Khairy drain that needs more treatment before discharging into the lake.

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Lake Burullus, as one of the northern deltaic lakes in Egypt, is an important economic, recreational and Fish breeding reservoir. The study used nine georeferenced stations to assess hydrogen sulphide (H2S) levels, its relationship with some selected hydrochemical parameters, and the implication on this lake’s biota. The study reveals that areas mostly affected by drainage water with high load of organic matter, aid to the production of H2S into sediments and dispersion to water. The results indicate that H2S levels in lake sediments increase with increasing water temperature, biological oxygen demand (BOD) and load of organic matter (OM) in water. On the other hand, clear water areas with high oxygen levels aid in reducing levels of H2S in sediments as proved from correlation analysis. The positive correlation between variables as OM and BOD with H2S was observed using the distribution maps. The amount of different wastes, particularly in large quantities, increase the level of H2S, and therefore affected biota so it is highly recommended to treat wastewater to conserve the biodiversity of this lake.

Nowadays, the importance of using macrophytes in accumulation of heavy metals has gained great concerns. So, this study aimed at extracting the land use/cover types of three indices and surface temperatures in the habitats inside 100 m buffers from recent satellite images around three highly economic macrophytes namely; Phragmites australis, Typha domingensis and Potamogeton pectinatus species. In addition to land surface temperature (LST), three important indices expressing the land cover of habitats namely; normalized different vegetation index (NDVI), normalized different water index (NDWI), and normalized different moisture index (NDMI) were extracted to find out there influence on the efficiency of macrophytes in the accumulation of these metal ions; Fe, Cu, Zn, Cd and Pb. The Polynomial regression models were calculated to predict the accumulation factors of plants within the remotely sensed indices and LST. Results showed different accumulation values for individual or more metals in the below-ground and above-ground parts of macrophytes within different habitats. This study considers as an innovative approach using remote sensing technique and satellite images for the selecting of species that can accumulate more metals within different habitats. The obtained results will be useful for the optimal management of these macrophytes in Lake Burullus, a Ramsar site.