Temporal variability of nutrient concentration in marine biofilm developed on acrylic panels

The quantification of chemical and biochemical composition is one of the common approaches to measure the biomass in biofilms. In the present study, temporal changes in the concentration of chemical and biochemical components like carbohydrate, protein, nitrate, nitrite, phosphate, calcium and magnesium were analysed for a period of one year by suspending acrylic panels at the Kudankulam waters in the Southeast Coast of India. Considerable variation in the concentration was observed in relation to exposure duration and also between sampling months. Carbohydrates showed the highest concentration of 2.32 mg cm− 2 on 10-day-old panels submerged during December 2005. Protein concentration reached a maximum of 0.676 mg cm− 2 during August 2005. Nitrate and nitrite showed their maximum concentration during April 2005. Except carbohydrate, all other compounds showed significant monthly variation, which indicates strong temporal variability in the organic and inorganic composition of biofilms. Carbohydrate concentration showed a significant decrease over exposure time in October and June. Results suggest that the observed temporal variability may be partly influenced by the concentration of these nutrients in the surrounding medium. A significant conclusion of this study is that biofilm development should be assessed over a range of temporal scales for advancing our understanding of biofilms.