Modelled distribution of marine biotopes in Astafjord, Sør-Troms.

This WMS map layer shows selected areas from the dataset "Seabed sediments (grain size), detailed" and indicates where fine sediments are likely to accumulate due to weak bottom currents. Such areas are typically dominated by silty and/or clayey and may include areas with fine-grained sediment deposited on top of coarser material. The map layer is intended for use at map scales 1:10 000 – 1:50 000.

Biotopes are areas with distinctive benthic communities and a similar physical environment. Each biotope usually has a unique composition of species. The species are determined by the environmental conditions in the area. Four areas have so far been mapped and modeled separately: the Barents Sea (MAREANO-mapped areas), TromsIII / NordlandVII, NordlandVI and the Central Norwegian shelf. The goal is to harmonize these datasets and create a comprehensive biotope map for Norwegian sea areas.

Datasettet viser utbredelsen av marine biotoper i Astafjordene i Sør-Troms. En biotop er et område med en bestemt sammensetning av plante- og dyrearter som lever under ensartede miljøforhold. Hvilke arter dette er, bestemmes av miljøforholdene i området. Ved hjelp av multivariate statistiske metoder og på grunnlag av detaljerte dybdedata, kornstørrelsesdata og info om bunnfauna fra video er det modellert 12 biotopklasser på havbunnen i Astafjorden, Vågsfjorden og Tranøyfjorden med sidefjordene. Biotopdata er et av mange kartproduktene av prosjektet «Marine grunnkart i Sør-Troms» (2002-2012).

The map is based on grain size distribution and indicates how easy it would be to dig into the sea floor, and how stable the dugout depression would be.

The map service presents a number of thematic layers derived from detailed basis information about the seabed: depth and sediment composition. The following themes are visualized: Bathymetry (terrain), Slope, Anchoring, Diggability, Accumulation basins and Habitats.

Slope is one of the terrain parameters derived from depth data. Slope shows where there are steep slopes or flat fjord bottom. Slope is presented in five steepness classes measured in degrees.