In contrast to the high urbanization level at the centre, unique biotopes of wetlands, meadows and dunes are found on the coastal areas and outskirts. The biotopes and species listed in Biotopes Directive ( EU Directive on the conservation of natural habitats and of wild fauna and flora 92/43/EEC, 1992,) and Birds Directive ( EU Directive on the conservation of wild birds 79/409/EEC, 1979) can be found there. Most typical biotopes are estuaries, boreal coastal meadows, embryonic shifting dunes, shifting dunes, wooded dunes of Boreal region , and others.

The biodiversity of the City is not investigated in whole. There is more detailed knowledge about diversity of nature-protected areas, forests and parks and gardens.