MARINE BIOGEOCHEMISTRY OF PARTICULATE TRACE ELEMENTS IN THE EXCLUSIVE ECONOMIC ZONE (EEZ) OF THE STATE OF QATAR
MARINE BIOGEOCHEMISTRY OF PARTICULATE TRACE ELEMENTS IN THE EXCLUSIVE ECONOMIC ZONE (EEZ) OF THE STATE OF QATAR
Abstract:
We focus on the trace element geochemistry of particulate matter in the Exclusive Economic Zone (EEZ) of Qatar. A main goal of this research was to analyze a complete suite of trace elements on particulate matter samples from the water column from different oceanographic biogeochemical zones of the EEZ around Qatar. The sample set also includes plankton samples which are the main source of biogenic particles, dust samples which are a source of abiological particles to surface seawater and surface sediments which can be a source of resuspended particles and a sink for settling particles. The 15 metals and 2 non-metals analyzed in this study will be Al, Ti, V, Cd, Co, Cu, Fe, Mn, Ni, Pb, Zn, Mo, Ag, Ba, U and P, N. Many factors control the composition of trace elements in marine particles. Most of these are important in the EEZ of Qatar, including:
1. Natural sources: These are rivers, atmospheric dust, sediment resuspension and leaks from oil beds. However, due to very limited rainfall rivers play no major role in Qatar but resuspension of shallow carbonate rich sediments and input of atmospheric dust are important due to strong currents and surrounding deserts.
2. Adsorption/desorption: These chemical processes occur everywhere in the ocean and transfer metals between particles and the solution phase.
3. Biological uptake: This process is likewise a universal ocean process and results in transport of metals from the solution phase to biological particles.
4. Redox conditions: These are important chemical reactions in the oxic, suboxic and anoxic zones. This can be the dominant controlling mechanism in the northeastern hypoxic deeper waters of the Qatar EEZ.
5. Anthropogenic sources: The eastern part of the Qatar contains numerous industrial sites, petroleum/gas platforms and refineries. There are numerous industrial sources but the main hot spots are the port of Doha and the industrial cities of Mesaieed, Khor Al-Odaid, and Ras Laffan. We aimed to determine the influence of the different current systems, water masses, and terrestrial inputs on the distribution, fractionation, and fate of trace metal contaminants and elemental pollutants. We have also observed the level of anthropogenic enrichments for some of the elements which have not been previously documented. This research should be viewed as the first stage of a complete study.
1. Natural sources: These are rivers, atmospheric dust, sediment resuspension and leaks from oil beds. However, due to very limited rainfall rivers play no major role in Qatar but resuspension of shallow carbonate rich sediments and input of atmospheric dust are important due to strong currents and surrounding deserts.
2. Adsorption/desorption: These chemical processes occur everywhere in the ocean and transfer metals between particles and the solution phase.
3. Biological uptake: This process is likewise a universal ocean process and results in transport of metals from the solution phase to biological particles.
4. Redox conditions: These are important chemical reactions in the oxic, suboxic and anoxic zones. This can be the dominant controlling mechanism in the northeastern hypoxic deeper waters of the Qatar EEZ.
5. Anthropogenic sources: The eastern part of the Qatar contains numerous industrial sites, petroleum/gas platforms and refineries. There are numerous industrial sources but the main hot spots are the port of Doha and the industrial cities of Mesaieed, Khor Al-Odaid, and Ras Laffan. We aimed to determine the influence of the different current systems, water masses, and terrestrial inputs on the distribution, fractionation, and fate of trace metal contaminants and elemental pollutants. We have also observed the level of anthropogenic enrichments for some of the elements which have not been previously documented. This research should be viewed as the first stage of a complete study.