A Peat-Producing Empetrum Heath in Coastal North Norway

Abstract

A conspicuous type of heath dominated by Empetrum hermaphroditum has been investigated in the western coastal region of Troms, northern Norway (70°N, 20°E). The soil of the Empetrum heath lacks mineral soil horizons and podsol development. Instead, a peat profile up to 1 m has accumulated, which resembles the pedology of ombrotrophic bogs rather than the other Empetrum-aominaiea communities in northern Norway. The high peat accumulation rate in this heath is probably a response to the cold and wet climate, the retarded metabolism of the carbon supply in the soil, and, possibly, allelopatic properties of Empetrum.

The heath type is classified as Pleurozio-Empetretum hermaphroditi Øvst. nov. ass. within the alliance Phyllodoco-Vaccinion myrtilli Nordh. 43. Several species with a coastal distribution pattern are associated with this community.

Palynological investigation indicates that one stand of this association has been stable, lacking Betula, for about 1400 yr. For this reason we believe that exposure to strong winds and sea spray, rather than grazing, is the primary factor preventing the establishment of Betula. This hypothesis is supported by the relatively high content of magnesium in the soil. The Empetrum heath is regarded as the climax community of convex siliceous habitats near the sea in the investigation area.