As a result of a collaboration with the Oceanography and Coastal Pollution Group of the University of Cadiz, an article has been published in the journal Science of the Total Environment. This work studies the levels and composition of Dissolved Organic Matter (DOM) in the Mar Menor lagoon, both in the water column and in the water contained in the sediment. A study was carried out in different areas and in different seasons of the year. The conclusions of the work were that the composition of MOD is mainly related to and enhanced by anthropogenic activities and microbial metabolism. MOD enters the lagoon through urban and agricultural runoff, drainage systems and sewage treatment plants. In addition, strong microbial metabolism in sediments leads to differences in MOD composition between water and sediments. In the water column, humic-type components accounted for 71% of the total MOD, whereas protein-type compounds were the most abundant in the sediment interstitial water. A strong seasonal variability associated with rainfall and the collapse of the system in 2016 that resulted in the death of 80% of the macrophytes was observed. Sediments act as a source of MOD to the lagoon water, probably due to relatively high organic matter content and intense microbial activity. Benthic MOD fluxes were higher in winter than in summer 2018 and decreased from north to south, probably related to shorter residence time in the northern basin, groundwater discharge and accumulation of organic matter from dead meadows.
Reference: Amaral, V., Santos-Echeandía, J., Ortega, T., Álvarez-Salgado, X.A., Forja, J., 2023. Dissolved organicmatter distribution in thewater column and sediment pore water in a highly anthropized coastal lagoon (Mar Menor, Spain):
Characteristics, sources, and benthic fluxes. Science of the Total Environment 896: 165264.
More information available at: https://www.sciencedirect.com/science/article/pii/S0048969723038871