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EN
Benthic total oxygen uptake (TOU) was measured in two Arctic fjords (NW Spitsbergen shelf) with different hydrological regimes: Hornsund with “cold” coastal Arctic waters and Kongsfjorden with “warm” Atlantic shelf waters. TOU rates in Kongsfjorden were more than 50% higher than in Hornsund. This is presumably related to the relatively higher biomass of bacterial and faunal (meiobenthos and macrofauna) communities in Kongsfjorden as compared to Hornsund caused by the source of organic matter: Kongsfjorden is dominated by marine, Hornsund by terrigenous organic matter. We conclude that the quality of organic matter supplied to marine sediments influences the biomass of benthic organisms and the rate of oxygen consumption. Therefore the Kongsfjorden sea bed has much higher oxygen uptake and hence a greater carbon demand than Hornsund.
2
Content available remote Can seabirds modify carbon burial in fjords?
EN
Two high latitude fjords of Spitsbergen (Hornsund 77°N and Kongsfjorden 79°N) are regarded as being highly productive (70 g and 50 gC m−2 year−1) and having organic-rich sediments. Hornsund has more organic matter in its sediments (8%), nearly half of it of terrestrial origin, while most of that in Kongsfjorden (5%) comes from fresh, marine sources (microplankton). Analysis of the carbon sources in both fjords shows that a major difference is the much larger seabird population in Hornsund-dominated with over 100 thousands pairs of plankton feeding little auks in Hornsund versus 2 thousand pairs in Kongsfjorden, and marine food consumption estimated as 5573 tonnes of carbon in Hornsund, versus 3047 tonnes in Kongsfjorden during one month of chick feeding period. Seabird colonies supply rich ornithogenic tundra (595 tonnes of C, as against only 266 tonnes of C in the Kongsfjorden tundra). No much of the terrestrial carbon, flushed out or wind-blown to the fjord, is consumed on the seabed – a state of affairs that is reflected by the low metabolic activity of bacteria and benthos and the lower benthic biomass in Hornsund than in Kongsfjorden.
3
Content available remote Colonies of Gyrosigma eximium: a new phenomenon in Arctic tidal flats
EN
For the first time at Svalbard, a colonial form of the tube-dwelling diatom Gyrosigma eximium was found in summer 2010 in the tidal flats on Spitsbergen at 78°N. The colonies take the form of conical, green structures that are 1–2 cm high and are associated with other diatom taxa and cyanobacteria (Oscillatoriaceae). The diatom colonies were associated with rich meiofauna and apparently act as cohesive factors for the fine sediment. In the Arctic tidal flats, this represents the first observation of long-term sediment stabilization and biological enrichment. Since this first observation, this species has apparently colonized broader areas in Advenentelva's tidal flat.
EN
Extensive sampling (450 grabs) was performed all over the inner part of Puck Bay (105 km2 area) in summers of 2007–2009. The GIS-based analysis of samples was performed to assess in detail the distribution of 32 benthic species. The minimum area of occurrence was less than 1 km2 for Lekanosphaera rugicauda and the maximum was 83 km2 for Cerastoderma glaucum. The material reveals that species with the pelagic larval stage were most widespread, with the least distance between individuals and the highest average density (e.g. Cerastoderma glaucum, Hydrobia ventrosa). The most isolated and the least dense species within the studied area were discretely mobile, non-larval crustaceans (e.g. Gammarus oceanicus and Lekanosphaera rugicauda), present at single sites with the largest distance from each other. We conclude that analysis of species distribution helps in understanding the threats to populations of marine invertebrates and marine spatial planning, through locating the isolated species and populations.
5
Content available remote Habitat modelling limitations - Puck Bay, Baltic Sea - a case study
EN
The Natura 2000 sites and the Coastal Landscape Park in a shallow marine bay in the southern Baltic have been studied in detail for the distribution of benthic macroorganisms, species assemblages and seabed habitats. The relatively small Inner Puck Bay (104.8 km2) is one of the most thoroughly investigated marine areas in the Baltic: research has been carried out there continuously for over 50 years. Six physical parameters regarded as critically important for the marine benthos (depth, minimal temperature, maximum salinity, light, wave intensity and sediment type) were summarized on a GIS map showing unified patches of seabed and the near-bottom water conditions. The occurrence of uniform seabed forms is weakly correlated with the distributions of individual species or multi-species assemblages. This is partly explained by the characteristics of the local macrofauna, which is dominated by highly tolerant, eurytopic species with opportunistic strategies. The history and timing of the assemblage formation also explains this weak correlation. The distribution of assemblages formed by long-living, structural species (Zostera marina and other higher plants) shows the history of recovery following earlier disturbances. In the study area, these communities are still in the stage of recovery and recolonization, and their present distribution does not as yet match the distribution of the physical environmental conditions favourable to them. Our results show up the limitations of distribution modelling in coastal waters, where the history of anthropogenic disturbances can distort the picture of the present-day environmental control of biota distributions.
6
Content available remote A huge biocatalytic filter in the centre of Barents Sea shelf ?
EN
A primary production model for the Barents Sea shows a hot spot of organic carbon settlement to the sea bed over 100 km long, a shallow pile of highly permeable sediments (mainly large Balanus, Mya and Pecten shell fragments over 1 cm in size) of glacial origin. Hydrodynamic flow models suggest an intensive, deep flow of near-bottom waters into the sediment. Depending on wave height, water in shallow (30 m depth) places may percolate more than 5 m into the sediment. During 10 days of stormy weather as much as 4 to 8 kg wet weight pelagic biomass can be processed per square metre through this extremely permeable sediment. Analogous processes known in coastal waters lead to intense biocatalytic phenomena and metabolism of organic carbon within the seabed, estimated here as more intense than surface consumption. Spitsbergenbanken may be acting as a huge sink for organic carbon and an important source of nutrients in one of the most productive areas of the North Atlantic.
7
EN
Submarine groundwater discharge (SGD) is one of the water pathways connecting land and ocean in the global water cycle. Moreover it has been recently recognized as important factor influencing coastal zone [5]. In comparison with easily seen and typically large point sources surface of water inputs (e.g. rivers and streams), which are gauged and well analysed, estimations of groundwater inputs are much more difficult due to lack of simple mean to gauge these fluxes [28]. Groundwater in many areas has become contaminated and therefore is a source of nutrients, trace metals, organic compounds and radionuclides.
PL
Dopływ wód podziemnych do środowiska morskiego jest obecnie postrzegany jako istotny szlak wymiany masy pomiędzy lądem i oceanem. Cechuje go znacząca przestrzenna i czasowa zmienność, w porównaniu do spływu rzecznego, co utrudnia jakościową i ilościową charakterystykę dopływających substancji. Dopływająca woda podziemna i zawarte w niej substancje (związki organiczne, substancje biogeniczne czy metale) wpływają w szczególności na przemiany geochemiczne w wodach przybrzeżnych. Badania dotyczące dopływu wód podziemnych do środowiska morskiego są prowadzone na świecie, w tym na Morzu Bałtyckim od wielu lat. Podjęto też badania dotyczące dopływu wody podziemnej - wody wysiękowej do Zatoki Gdańskiej. Próbki wody są pobierane za pomocą batometrów, kolektorów wody wysiękowej i piezometrów, a następnie analizowane. Ustalono że, wody wysiękowe zawierają substancje biogeniczne, rozpuszczony węgiel nieorganiczny oraz metale śladowe w szerokich zakresach stężeń. Otrzymane wyniki stężeń badanych komponentów wody korelują z zasoleniem i pH. Dalsze badanie zjawiska dopływu wód wysiękowych i ich charakterystyki jest niezbędne dla lepszego zrozumienia zasad funkcjonowania ekosystemów morskich oraz określenia niebezpieczeństw zagrażającym im, związanych z dopływem dużych ilości substancji toksycznych.
8
EN
A biological valuation system to assess the value associated with ecosystem stability and richness (and not that from the point of view of users) is proposed to provide scientific decision support for marine protected areas and marine spatial planning. The system is based on the assessment of individual species and habitat/species assemblages. An extensive set of recently collected (2007-08) and archival (1970-2000) data on the occurrence of marine benthos was analysed for the Polish Marine Areas. Based on matching data sets of sediments, the euphotic zone, temperature and salinity, as well as fetch and sea current values, a GIS model was used to visualise the results; a map indicates the two areas which are considered to be biologically the most valuable (Puck Bay and the stony shallows of the central coast).
EN
This paper summarises current knowledge of goods and services in the Polish Exclusive Economic Zone of the Baltic Sea ecosystem. It reviews specific properties of the Baltic that could be used for economic valuation. Goods and services range from the familiar resources of fish and minerals, which were valued with the Productivity Method, to less obvious services provided by the ecosystem such as biofiltration in coastal sands, valued with either the Replacement Cost or Damage Cost Avoided methods. Disservices to the marine ecosystem are also considered, e.g. erosion and coastal flooding, including the costs of planned mitigating measures. This paper emphasises the importance of using valuation methods to help make better-educated decisions for the sustainability of the Baltic Sea.
11
Content available remote Fine organic particles in a sandy beach system (Puck Bay, Baltic Sea)
EN
A total of over 550 samples of particulate organic matter (POM) were obtained from swash and groundwater samples taken on a monthly basis from seven localities on the sandy shores of Puck Bay in 2002 and 2003. Sandy sediment cores from the swash zone were collected to assess the amount of POM in the pore waters. The mean annual concentrations of POM varied between localities from 20 to 500 mg in groundwater and from 6 to 200 mg dm-3 in swash water. The carbon/nitrogen (C/N) ratio in suspended matter was always higher in groundwater (annual mean 12) than in swash water (annual mean 7). The C/N ratio indicates a local, algal origin of POM in the shallow coastal zone.
EN
The aim of this study was to evaluate the amount of organic macrodetritus deposited on the sandy shores of the southern Baltic, and to determine the type of washout material and their chemical composition (carbon and nitrogen). Over 900 samples of macrodetritus (particles retained on a 0.5 mm sieve) were collected from seven sampling locations along a 120 km stretch of coastline in Poland at monthly intervals in 2002. Analysis of the C and N content of several categories of detritus supplied information about seasonal changes in and the ageing of algal debris, and indicated that the amount of carrion is constant; the latter is apparently always metabolised very rapidly. The annual deposition of macroalgal detritus on this coast was estimated at 15 000 tonnes fresh weight, that is around 75% of the primary production of filamentous macroalgae in Puck Bay. In comparison with the amounts of kelp deposited on sandy beaches in South Africa (Griffiths & Stenton-Dozey 1981), the massive seaweed washouts on Mediterranean beaches (Morand & Briand 1996), or the deposition of algal mats in the northern Baltic (Norkko & Bonsdorff 1996a), the quantities of macrodetritus on the shore in the study area are average, even allowing for the fact that the Baltic Sea is highly eutrophic (HELCOM 2005).
EN
Sopot's intensively used sandy beach was studied to assess organic matter deposition and swash water filtration through the sediment on the water line. The swash water contained from 4 to 80 mg Total Suspended Matter (TSM) per dm3, 3 to 12% of it was organic. Phytoplankton ranged from 1 to 15 million cells per dm3, depending on the water turbidity and contained a mixture of pelagic and micro-phytobentic taxa. Plankton larvae and Rotatoria dominated the animal biomass. In the process of wave filtration through the sand all planktonic animals were retained in the sediment, while a number of meiofaunal Nematoda and Ciliata were actively transported ("washed out") from the upper sediment layers. Macroscopic particle (filamentous algae) deposition in May ranged from 20 to 1000 g POC m-2 per day. Nutrient concentrations were higher in the interstitial water than in the swash water, for most of the year. Hence, we suppose that the Sopot municipal beach serves as a nutrient source for coastal waters.
EN
Unlike dunes, sandy beaches and the littoral zone are usually regarded as non-vulnerable. The biodiversity and biomass of interstitial organisms are low. How-ever, recent findings have shown that marine sands transfer energy very ef-fectively, and that chemical and biological reactions take place faster there than in fine-grained sediments. The importance of the microphytobenthos and bacteria to this system is little known. The effects of recreational pressure (trampling, beach cleaning and nourishment) are not well understood. A pilot study from the Baltic Sea shows the importance of trampling as a form of bioturbation, a very effective way of fragmenting and mixing organic matter with the sand. The high diversity of diatoms and meiofauna in undisturbed beaches may act as an effective biological filter for some types of pollutants, while less diverse, but more abundant biota in disturbed areas are more effective in processing organic matter (self-cleaning of the beach).
EN
The aim of the study was to determine the distribution, composition and seasonal variability of macrozoobenthos in the sandy littoral zone of the military area between Hel and Jurata. The results of qualitative and quantitative investigations of the benthic fauna are presented. The material was collected monthly from November 1991 till November 1992 at 10 stations situated in the sandy littoral zone (0.5-1 m depth) on the Puck Bay shore of the Hel Peninsula. A total of 17 macrofaunal taxa were identified. At each station 2 or 3 subsamples were collected with a 225 cm2 Petersen grab. The average abundance and wet weight of particular taxa were calculated. Bathyporeia pilosa, Hediste diversicolor and Oligochaeta were most frequent taxa in the study area. Polychaeta and Bivalvia constituted up to 93% of the bottom fauna biomass, Hediste diversicolor was the dominant species.
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