https://karttapalvelu.lounaistieto.fi/

From the dataset abstract

Pilot scheme for setting values for underwater habitats.This dataset shows a valuation of underwater communities. The dataset is based on three research areas: Archipealgo Sea, Raseborg area and Kotka. The Archipelago dataset is based on dive transects conducted by the NANNUT project in August and September 2010 and 2011 in the Archipelago Sea. The Kotka dataset ataset shows locations where underwater data was collected by the projects NANNUT and VELMU during August 2011 in Kotka near the Mussalo harbor.

Archipelago dataset: Each investigated square along the diveline is given a value (1-5) according to a valuation where locations with a high value have high species richness or vegetation cover, red listed species, are potential fish spawning sites, or otherwise representative important habitats. OBS! The valuation is based on vegetation and mussel coverage data. Low value locations can have other nature values that have not been studied here (e.g. rich benthic fauna or be important fish spawning sites).

Kotka dataset: The dataset contains information on the occurrence of ecological communities based on the percent coverage of plants and mussels. The communities analysed are vascular plant, stoneworth and seagrass meadows, bladderwrack and redalgae belts, as well as blue mussel/zebra mussel beds and mixtures of the above. The pies show the disribution of communities on each dive transect.

Source: Community valuation - divelines 2012