Spatial Analysis of Chlorophyll-a and Its Correlation with Temperature, Phosphate, and Nitrate in Marine Waters of Abu Dhabi, UAE

Chlorophyll-a is a primary indicator of phytoplankton biomass and is an essential parameter for evaluating Marine Water Quality (MWQ). This study explored the relation between sea surface temperature (SST), Chlorophyll-a (Chl-a), Phosphate (PO4), and Nitrate (NO3) concentrations to support in the monitoring and evaluation of the marine environment. Monthly sampling was conducted at 22 ecologically important sites in the Abu Dhabi marine environment, encompassing eight categories, including confined areas, near desalination plants, natural habitats, port and marinas, near nuclear power plant, near public beaches, newly developed area and reference (offshore water). Results revealed Chl-a concentrations ranging from 0.2 to 62.8 µg/L (mean 2.05 µg/L), SST from 18.99 to 34.93 °C (mean 28.64 °C), PO4 from 5.46 to 2967 µg/L (mean 182.67 µg/L), and NO3 from 14.17 to 15 599.3 µg/L (mean 369.13 µg/L). Site 2 showed the highest mean Chl-a (24.26 µg/L), PO4 (1329.36 µg/L), and NO3 (4316.17 µg/L), while Site 13 had the highest mean SST (29.37 °C). Confined areas recorded the highest mean concentrations of Chl-a (7.47 µg/L), PO4 (462.28 µg/L), and NO3 (1332.02 µg/L), while reference areas showed the highest SST (29.06 °C). Statistical analysis correlation indicated that Chl-a positively correlates with PO4 (0.603) and NO3 (0.433) but negatively correlates with SST (-0.076). SST showed negative correlations with PO4 (-0.188) and NO3 (-0.167), while PO4 and NO3 had a strong positive correlation (0.714). These results provide valuable information into the physical and chemical parameters and their correlations in Abu Dhabi waters