Effect of upwelling on the pelagic environment and bloom-forming cyanobacteria in the western Gulf of Finland, Baltic Sea

Vahtera, Emil; Laanemets, Jaan; Pavelson, J.; Huttunen, Maija; Kononen, Kaisa

doi:10.1016/j.jmarsys.2005.07.001

Cited by 96 publications

(73 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The fluctuations in cyanobacterial structure and abundance are regulated by the concentration of nutrients, thermal stratification of water masses, weather-induced water mixing or upwelling events (Laamanen & Kuosa, 2005;Vahtera et al, 2005;Laanemets et al, 2006;Vahtera et al, 2007;Nausch et al, 2008;Mohlin et al, 2011). In our studies, the heterogenic character of cyanobacterial occurrence in the Southern Baltic Proper was documented.…”

Section: Occurrence Of Diazotrophic Cyanobacteria and Picocyanobactersupporting

confidence: 51%

“…Although in the last 30 years, a reduction in nutrients loading to the sea has been achieved, the internal sources of the nutrients are still sufficient to sustain the blooms of phytoplankton organisms (Vahtera et al, 2005). Among these sources, N 2 fixation by cyanobacteria and the release of phosphorous from anoxic sediments are most significant (Emeis et al, 2000;Conley et al, 2002;Tamminen & Andersen, 2007;Vahtera et al, 2007).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Occurrence of cyanobacteria and cyanotoxin in the Southern Baltic Proper. Filamentous cyanobacteria versus single-celled picocyanobacteria

et al. 2012

View full text Add to dashboard Cite

In the Baltic Sea, cyanobacterial community is mainly composed of filamentous nitrogen-fixing forms, including the toxic Nodularia spumigena, and single-celled picocyanobacteria (Pcy), represented by Synechococcus spp. The main aim of the work was to test the hypothesis that the picocyanobacteria dependend on the presence of the nitrogen-fixing cyanobacteria. In addition, the contamination of blue mussels and fish with nodularin (NOD), the N. spumigena toxin, was examined. In years 2008-2011, the samples for the study were collected in the Southern Baltic Proper using FerryBox system and, occasionally, during research cruises. The analyses showed no correlation between the growth of the nitrogen-fixing cyanobacteria and Synechococcus. Compared with the previously published data, a shift in the composition of Pcy phenotypes was observed. This shift might be an indication of the proceeding changes induced by the reduced nutrient loading and/or climate change. Analyses of NOD revealed differences in the cyanotoxin concentrations between mussels of different shell size. The highest concentration of NOD was detected in the liver of round goby. However, temporarily, also the fish muscles were significantly contaminated with the toxin.

show abstract

Section: Occurrence Of Diazotrophic Cyanobacteria and Picocyanobactersupporting

confidence: 51%

Section: Introductionmentioning

confidence: 99%

Occurrence of cyanobacteria and cyanotoxin in the Southern Baltic Proper. Filamentous cyanobacteria versus single-celled picocyanobacteria

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Upwelling is a typical, well-documented phenomenon in the Baltic Sea (Alenius et al, 1998;Vahtera et al, 2005;Lehmann and Myrberg, 2008;Lips et al, 2009). The process is characterized by winds blowing predominantly parallel to the coast from a favorable direction.…”

Section: Upwellingmentioning

confidence: 99%

One year of continuous measurements constraining methane emissions from the Baltic Sea to the atmosphere using a ship of opportunity

et al. 2013

View full text Add to dashboard Cite

Abstract. Methane and carbon dioxide were measured with an autonomous and continuous running system on a ferry line crossing the Baltic Sea on a 2-3 day interval from the Mecklenburg Bight to the Gulf of Finland in 2010. Surface methane saturations show great seasonal differences in shallow regions like the Mecklenburg Bight (103-507 %) compared to deeper regions like the Gotland Basin (96-161 %). The influence of controlling parameters like temperature, wind, mixing depth and processes like upwelling, mixing of the water column and sedimentary methane emissions on methane oversaturation and emission to the atmosphere are investigated. Upwelling was found to influence methane surface concentrations in the area of Gotland significantly during the summer period. In February 2010, an event of elevated methane concentrations in the surface water and water column of the Arkona Basin was observed, which could be linked to a wind-derived water level change as a potential triggering mechanism. The Baltic Sea is a source of methane to the atmosphere throughout the year, with highest fluxes occurring during the winter season. Stratification was found to promote the formation of a methane reservoir in deeper regions like Gulf of Finland or Bornholm Basin, which leads to long lasting elevated methane concentrations and enhanced methane fluxes, when mixed to the surface during mixed layer deepening in autumn and winter. Methane concentrations and fluxes from shallow regions like the Mecklenburg Bight are predominantly controlled by sedimentary production and consumption of methane, wind events and the change in temperature-dependent solubility of methane in the surface water. Methane fluxes vary significantly in shallow regions (e.g. Mecklenburg Bight) and regions with a temporal stratification (e.g. Bornholm Basin, Gulf of Finland). On the contrary, areas with a permanent stratification like the Gotland Basin show only small seasonal fluctuations in methane fluxes.

show abstract

“…nificantly affect the biological production, retention, and transport, have been observed in the Gulf of Finland (e.g., Talpsepp et al, 1994;Kononen et al, 1996;Pavelson et al, 1997;Vahtera et al, 2005;Lips et al, 2009).…”

Section: Introductionmentioning

confidence: 99%

“…Most prominent upwelling events that were captured by measurements are an event along the northern coast in July 1999 (Vahtera et al, 2005) and an event along the southern coast in August 2006 ). The following characteristic features of upwelling events in the Gulf of Finland are suggested:…”

Section: Introductionmentioning

confidence: 99%

Upwelling characteristics in the Gulf of Finland (Baltic Sea) as revealed by Ferrybox measurements in 2007–2013

Kikas

Lips

2016

Ocean Sci.

View full text Add to dashboard Cite

Abstract. Ferrybox measurements have been carried out between Tallinn and Helsinki in the Gulf of Finland (Baltic Sea) on a regular basis since 1997. The system measures autonomously water temperature, salinity, chlorophyll a fluorescence and turbidity and takes water samples for further analyses at a predefined time interval. We aimed to show how the Ferrybox technology could be used to study the coastal upwelling events in the Gulf of Finland. Based on the introduced upwelling index and related criteria, 33 coastal upwelling events were identified in May-September 2007-2013. The number of events, as well as the frequency of their occurrence and intensity expressed as a sum of daily average temperature deviations in the 20 km wide coastal area, were almost equal near the northern and southern coasts. Nevertheless, the wind impulse, which was needed to generate upwelling events of similar intensity, differed between the northern and southern coastal areas. It is suggested that the general thermohaline structure adapted to the prevailing forcing and the estuarine character of the basin weaken the upwelling created by the westerly to southwesterly (up-estuary) winds and strengthen the upwelling created by the easterly to northeasterly (down-estuary) winds. Two types of upwelling events were identified -one characterized by a strong temperature front and the other revealing gradual decrease in temperature from the open sea to the coastal area, with maximum temperature deviation close to the shore.

show abstract

Effect of upwelling on the pelagic environment and bloom-forming cyanobacteria in the western Gulf of Finland, Baltic Sea

Cited by 96 publications

References 29 publications

Occurrence of cyanobacteria and cyanotoxin in the Southern Baltic Proper. Filamentous cyanobacteria versus single-celled picocyanobacteria

Occurrence of cyanobacteria and cyanotoxin in the Southern Baltic Proper. Filamentous cyanobacteria versus single-celled picocyanobacteria

One year of continuous measurements constraining methane emissions from the Baltic Sea to the atmosphere using a ship of opportunity

Upwelling characteristics in the Gulf of Finland (Baltic Sea) as revealed by Ferrybox measurements in 2007–2013

Contact Info

Product

Resources

About