Variation in Plant Community Composition and Biomass to Macro and Micronutrients and Salinity across Egypt’s Five Major Coastal Lakes

Abstract

To better assess the relationship between excess nutrient runoff and plant species diversity in the Egyptian northern coastal lakes, the relationships between aboveground biomass, species diversity, and both micro and macronutrient concentrations in sediment, water, and plant materials were investigated. A total of 38 sampling sites were established for the five Egyptian northern lakes (8 for Bardawil, 10 for Manzala, 8 for Burullus, and 6 for each of Edku and Mariut). Sediment, water, and plant materials were collected and analyzed for both micro and macronutrients including nitrogen (N), phosphorus (P), sulfur (S), magnesium (Mg), calcium (Ca), potassium (K), iron (Fe), boron (B), sodium (Na), and aluminum (Al). Based on the Sørensen similarity index, Burullus and Mariut lakes were very similar (0.70) in their vegetation composition, while Bardawil Lake had no similarity with the rest of the lakes. In sediment, Mariut Lake had the highest total P concentrations (1.3 g kg−1), while Bardawil Lake had the lowest (0.3 g kg−1). Bardawil, a hypersaline lake, had the highest concentrations for both Na and B (9.6 and 0.1 g kg−1, respectively). Among the deltaic lakes, Mariut Lake water bodies had the lowest plant species richness. The current study indicated that the excessive agricultural and industrial nutrient runoff had a greater impact on the nutrient distribution pattern and negatively impacted plant species diversity at the Egyptian coastal lakes. An integrated management plan, including establishing more pretreatment facilities for runoff and wastewater, should be implemented to reduce the nutrient loads from the main industrial and agricultural runoff sources. Moreover, periodic monitoring and assessment for nutrient runoff reaching the lakes are necessary to help reduce eutrophication levels.

Soils with more clay and dense vegetation were rich in soil carbon along Wadi Al-Sharaea, Makkah, Saudi Arabia

“…Soil is a complex system and factors affecting spatial variability of SOC content are, to a great extent, unknown [ 14 ]. Land use, soil texture, bedrock material, electrical conductivity, plant species diversity, shoot/root biomass allocation, hydrology, and various microbial activities govern the SOC content spatial variability [ [13] , [14] , [15] , [16] , [17] , 60 , 61 ]. Moreover, soil aggregation and C storage capacity would impact the SOC content buildup and SOM persistence [ 18 , 19 ].…”

Modeling Soil Organic Carbon at Coastal Sabkhas with Different Vegetation Covers at the Red Sea Coast of Saudi Arabia

“…A decreasing trend of proportional (%) SOC density (from top to bottom) was observed among all different vegetation covers (Figure 6). The variation of the SOC density over the soil profile could be impacted by biomass allocation, root/shoot ratio, root depth [86], plant species diversity [87][88][89], and variation of microbial activities [90,91] at different soil intervals.…”

Phytogeographical regions of Egypt: first open-source geospatial data and its applications

“…For the last few decades, phytogeographical regions of Egypt, especially Nile Delta, were severely impacted by human activities [ 15 ] including cultivation for Wadi deltaic regions, medicinal plant harvesting due to their economic and medical values, new cities creation, and road establishment [ 15 – 18 ]. Such anthropogenic activities impacted the natural flora and changed geographical distribution of plant species [ 16 – 22 ].…”