Branka Pestorić

Distribution of phytoplankton community in Kotor Bay (south-eastern Adriatic Sea)

The goal of this paper was to explain variability of phytoplankton in a shallow coastal area in relation to physico-chemical parameters. Temporal variability and composition of phytoplankton were investigated in the Kotor Bay, a small bay located in the south-eastern part of the Adriatic Sea. Samplings were performed weekly from February 2008 to January 2009 at one station in the inner part of the Kotor Bay, at five depths (0 m, 2 m, 5 m, 10 m, 15 m). Phosphates, nitrites and nitrates ranged from values under the level of detection to the maximum values of 1.54, 1.53 and 23.91 µmol l−1, respectively. The phytoplankton biomass — represented by chlorophyll a concentration — ranged from 0.12 to 6.78 mg m−3, reaching a maximum in summer. Diatoms were present throughout the whole sampling period, reaching the highest abundance in March (3.42×105 cells l−1at surface). The peak of dinoflagellates in July (2.2×106 cells l−1 at surface) was due to a single species, Prorocentrum micans. The toxic dinoflagellate Dinophysis fortii occurred at a concentration of 2140 cells l−1 in May. The present results of phytoplankton assemblages and distribution provide valuable information for this part of the south-eastern Adriatic Sea where data is currently absent.

Phytoplankton Community and Trophic State in Boka Kotorska Bay

Compiling the available data collected over many years of research of Boka Kotorska Bay showed variability in terms of dynamics and abundance of phytoplankton organisms. The Boka Kotorska Bay is a relatively large (87 km2), semi-enclosed bay, located in the south-eastern part of the Adriatic Sea. In addition to human impact, significant inflow of freshwater from numerous karstic streams and submarine springs contributes to the unique ecological characteristics of the Bay, particularly in its inner part (the Kotor Bay). Based on the data presented for the Boka Kotorska Bay (the Kotor Bay) phytoplankton abundance reaches up to 107 cells/l. Diatoms are the phytoplankton group present throughout the year. In some researches conducted in the Boka Kotorska Bay diatoms abundance reaching up to 107 cells/l was recorded. Dominant species are typical of areas with higher eutrophication that prefer nutrient rich areas and are very good indicators of ecosystem conditions. Dinoflagellates are the second important group of microplankton, frequently found in the aquatorium of the Boka Kotorska Bay. Dinoflagellates are generally less represented than diatoms, both quantitatively and qualitatively.

Zooplankton Community in the Boka Kotorska Bay

This study includes a review of recently published results regarding zooplankton in the Boka Kotorska Bay (since 2009), and comparison of these results with earlier investigations. Non-loricate ciliates were the most numerous microzooplankton in spring 2013 (37%). Loricate ciliates (tintinnids) values were low and similar to those recorded in the open Adriatic Sea. However, their diversity was quite high: 20 estuarine–neritic and 26 species typical of the open sea were identified. Copepod nauplii were dominant metazoan microzooplankton component (32%). Seven phylums and 81 mesozooplankton taxa were determined. Copepods were the most dominant group. Among them, Oncaea–cyclopoids and Oithona nana were the dominant copepod taxa at all stations. Heterotrophic dinoflagellate Noctiluca scintillans and cladocera Penilia avirostris were often extremely numerous during warm seasons. Changes in the zooplankton community noted during recent investigations can be linked with the observed climate changes identified in the Adriatic and Mediterranean Sea since the 1990s, which are reflected in: (1) zooplankton high densities in the winter period with a lack of spring peak; (2) domination of small-size cyclopoid copepods and decreasing of contribution of neritic calanoid species; (3) prolongation of high Penilia avirostris abundance in the autumn period; (4) spreading of invasive siphonophorae Muggiaea atlantica in the inner part of the Bay; (5) frequent outbreaks of gelatinous zooplankton; and (6) The first registered bloom of the ctenophore Bolinopsis vitrea in the Mediterranean in spring 2014, having a major impact on the regular planktonic food web system.

Satellite Remote Sensing of the Boka Kotorska Bay

In the chapter we show capabilities of satellite remote sensing for environmental monitoring of the Boka Kotorska Bay. A small size of the Bay requires usage of high-resolution satellite data from the Landsat, SPOT, Radarsat-2, QuickBird, FORMOSAT-2, Sentinel-1A, Sentinel-2A, and other space platforms with spatial resolution of 1–30 m. Most of high-resolution satellite data are very expensive; this is why we focus on those data, which are available free of charge. Examples of processed satellite imagery in true color, sea surface temperature, water turbidity, chlorophyll-a concentration, and sea surface roughness are presented. Forest fires, which constitute a yearly problem in Montenegro, are also well detected on satellite imagery.