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Modelled photic zone (BALANCE)

Summary


Model results for the distribution of where at least 1% available light touches the seabed (the photic zone) and non-photic zone in the Baltic Sea based on 1% mean annual irradiance


Description


This dataset shows model results forthe distribution of where at least 1% available light touches the seabed (the photic zone) and non-photic zone in the Baltic Sea based on 1% mean annual irradiance. From an ecological point of view, available light is one of the primary physical parameters influencing and structuring the biological communities in the marine environment, as it is the driving force behind the primary production by providing the energy for the photosynthesis - energy that ultimately is transferred to other organisms not capable of photosynthesis. The depth of the photic zone is traditionally defined, for benthic plants, as the depth where 1% of the surface irradiance (as measured just below the water surface) is available for photosynthesis. Only two intervals based on light regime were used in the dataset, because they reflect the significant ecological difference between the shallow water depth with the presence of submerged aquatic vegetation, and the deeper waters where fauna (and bacteria) dominate diversity of species, abundance, and biomass. The intervals are: I. The photic zone (where at least 1% of the available light touches the seabed). II. The non-photic zone.The measurements of Secchi Depth used for producing this dataset are not evenly distributed and some areas in the Baltic Proper, Gulf of Riga and southern Baltic are not well covered.

Simple

Date (Publication)
2008
Unique resource identifier
https://metadata.helcom.fi/geonetwork/srv/eng/catalog.search#/metadata/3c56d9a9-7efb-4c16-a66d-433b62f3e326
pointOfContact
  HELCOM Secretariat

GEMET - INSPIRE themes, version 1.0

  • Oceanographic geographical features

GEMET

  • oceanography

  • ocean

Keywords
  • MADS

  • photic depth

  • MADS

  • secchi depth

Continents, countries, sea regions of the world.

  • Europe

  • Baltic Sea

Use constraints
Other restrictions
Other constraints

Use constraints: Free for non-commercial purposes. Reference must be made to data source (BALANCE).

Access constraints
Other restrictions
Other constraints
Access constraints: No limitations on public access.
Spatial representation type
Grid
Metadata language
English
Topic category
  • Environment
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Begin date
2007-01-01
Unique resource identifier
EPSG:3035
Distribution format
  • TIFF ( )

OnLine resource
Download dataset ( WWW:LINK-1.0-http--link )
OnLine resource
Open in Map Viewer ( WWW:LINK-1.0-http--link )
Hierarchy level
Dataset

Conformance result

Date (Publication)
2010-12-08
Statement

This dataset shows model results forthe distribution of where at least 1% available light touches the seabed (the photic zone) and non-photic zone in the Baltic Sea based on 1% mean annual irradiance. (Data source: DHI Water - Environment - Health and ICES, produced by BSR INTERREG IIIB project BALANCE)


For the purpose of mapping the photic zone in the Kattegat and Baltic Sea water transparency has been calculated utilizing Secchi disc depth. The data have been collected at the ICES homepage, http://www.ices.dk/Ocean/project/secchi/ (Aarup 2002). The data

covers measurements of Secchi disc depth (SD) from the period 1903 to 1998. However, for this study only data from 1980-1998 was used. Also, only data between March to October have been included to account for the productive period providing approximately 20.000 records. In situations where frequent data are available at the same station, the data have been averaged per station resulting in approximately 2800 records covering most of the Baltic Sea area and Kattegat. These 2800 records have been spatially interpolated and extrapolated to cover the Baltic Sea. With this approach the station locations is weighted equally with the number of measurements. Despite the rich amount of data, the measurements of SD are not evenly distributed and areas in the Baltic Proper, Gulf of Riga and southern Baltic are not well covered.


For more information about this dataset see BALANCE Interim Report no. 10 "Towards marine landscapes in the Baltic Sea": http://balance-eu.org/xpdf/balance-interim-report-no-10.pdf.

File identifier
3c56d9a9-7efb-4c16-a66d-433b62f3e326 XML
Metadata language
English
Character set
UTF8
Hierarchy level
Dataset
Date stamp
2023-11-10T14:22:17
pointOfContact
  HELCOM Secretariat
 
 

Overviews

Spatial extent

N
S
E
W
thumbnail


Keywords

GEMET
ocean oceanography
GEMET - INSPIRE themes, version 1.0
Oceanographic geographical features

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Associated resources

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