Investigation on the dust effects on sea primary production in the Persian Gulf using remote sensing data

Document Type : Research Paper

Abstract

Atmospheric dusts have nutrients elements such as iron and aluminum, which they have an impacts on primary production in the sea. In this study, ten years of AOT and chlorophyll_a data was used to investigate relationship between them in the Persian Gulf. Investigation of monthly aerosol optical thickness and chlorophyll concentration from 2004 to 2013 showed that there is high correlation between them. So that, with increasing of optical thickness, chlorophyll concentration increase and with decreasing of optical thickness, chlorophyll concentration decrease. Results showed that in spring and summer with high level of dust concentration, dust has significant effect on primary production but in winter with low level of dust concentration, dust has not significant effect on primary production. High frequency of dust events may reduce sea surface radiation intensity, chlorophyll concentration and primary production which they are directly related to the light and radiation intensity. But if the increasing of dust concentration is associated with increasing of nutrient elements and no significant reduction of radiation intensity, the concentration of Chla and primary production will increase. There is a time delay of a few days between AOT and Chl_a peaks, which is due to the time required for iron deposition, dissolution and assimilation. This study shows significant relationship between aerosol optical thickness and chlorophyll concentration in the Persian Gulf using satellite remote sensing data.

Keywords