Temporal variability of nutrients and chlorophyll a in the Boka Kotorska bay, eastern Adriatic Sea

The Boka Kotorska bay, located in the SE part of Adriatic See, is influenced by great influx of fresh waters from numerous water streams and submarine springs. Seawater samples were taken from five depths (0, 2, 5, 10 and 15 m) weekly, at one station in Kotor bay, from March 2008 to February 2009. Nutrient salts varied widely, with maximum values 23.91 μmol dm−3 for nitrates, 1.52 μmol dm−3 nitrites and 0.77 μmol dm−3 for phosphates. Chlorophyll a concentration ranged from 0.12 to 11.13 mg m−3 and the highest value was measured in winter period of the year (February). It seems that the reason for this is the land-based nutrient input into the coastal area. According to the different criteria for nutrients and chlorophyll a concentration the area could be mesotrophic, and we could conclude that the natural eutrophication still prevails over the anthropogenic eutrophication in this part of the Adriatic Sea. This study should help in determining future data needs for monitoring of water quality and human and climate influence on the health of the bay.