Distribution of Nutrients and Chlorophyll-a in Mangrove Environment of Red Sea Coast of Yemen

The present study is aimed at screening for the concentration of nutrients and chlorophyll-a in mangrove environment of Red Sea coast of Yemen. N-NO₂ concentration ranged from 0.50 μg/L at Kamaran Island to 2.20 μg/L at Al-Zubayr with mean of 1.483 μg/L. N-NO₃ concentration ranged from 0.70 μg/L at Kamran Island to 3.10 μg/L at Dhubab with mean of 1.917 μg/L. N-NH₄ concentration ranged from 0.30 μg/L at Al-Zubayr to 1.00 μg/L at Dhubab with mean of 0.608 μg/L. P-PO₄ concentration ranged from 2.50 μg/L at Al-Zubayr to 6.10 μg/L at Al-Hodiedah with mean of 4.333 μg/L. Si-SiO₂ concentration ranged from 15.30 μg/L at Al-Zubayr to 23.40 μg/L at Al-Hodiedah with mean of 18.833 μg/L. Chlorophyll-a concentration ranged from 0.200 μg/L at Al-Zubayr to 0.320 μg/L at Al-Hodiedah with mean of 0.263 μg/L. The maximum concentration of nutrients, found at the levels of minimum oxygen and relatively high ammonia concentration, is usually attributed to recycling of nutrients by phytoplanktonic and bacterial activities. The high concentration of phosphate may be attributed to the freshwater inflows as a result of heavy rains in the highlands. The high concentration of silicate may be attributed to severe sandstorms affecting the coastal areas. The concentration of chlorophyll-a may be attributed to the water mass that contains nutrients as well as phytoplankton.