Scandinavian coastal conifer forests

Location and description

The Scandinavian coastal conifer forest PA0520 is a terrestrial ecoregion as defined by WWF. and National Geographic. The broad definition is based on climatic parameters and includes a long area along the western Norwegian coast from Lindesnes and north to approximately Senja (further north summers are too cool for pine to grow in coastal areas); in essence areas along the Norwegian coast where precipitation is high and winters are fairly mild. It might include areas lacking naturally occurring conifer forests (as in Lofoten, where the pine forest was cleared by man many centuries ago) and even islands and rocky headlands with little or no woodland and forest.

At somewhat higher elevations near the treeline in the Scandinavian mountains is the Scandinavian montane birch forest and grasslands ecoregion. In some areas along valleys, this ecoregion meet the taiga of the inland belonging to the Scandinavian and russian taiga ecoregion without mountain barriers. Examples of such valleys include the Rauma valley connecting Åndalsnes to Lesja and Dombås and the Namdalen valley connecting the Nord-Trøndelag coast to the cold interior with connection into Sweden. The ecoregion is naturally fragmented by fjords and mountains. The pine forests in the northern part have some of the oldest trees in Scandinavia, some more than 700 years old in Forfjord valley at Hinnøya.

Humid oceanic climate

This area has a long growing season for the latitude (140–215 days, longest in the south) with plentiful and reliable precipitation all year, from 1,200–3,000 mm. July 24-hr average temperatures typically range from 12–15 °C, with daytime highs of 14–20°C (warmest days in sheltered fjord areas). Winters are fairly mild and rainy, January average range from −3° to 2°C with daytime high at or above freezing. The mean annual temperature is approximately 7°C on the southwestern coast (Bergen 7.6°C, Stryn 6.4), 5.5°C on the Trøndelag/central Norway coast (Åfjord 5.7°C) and 4°C in the northernmost area of this ecoregion (Bodø 4.5°C, Gryllefjord/Senja 3.6°C). This type of climate corresponds to the Köppen type Cfb and Cfc, and is comparable to the climate along the coast of northern British Columbia and the Alaska Panhandle.

For the smaller area classified as rainforest, there is at least 200 days/year with measurable precipitation. The minimum mean annual precipitation given in the sources varies somewhat but are generally around 1.400 mm, while the typical value on these locations are 1,500–2,200 mm annually. Summers are mild; warm weather usually does not last long, and really hot weather is virtually unknown or very short lasting. Winters are generally mild and rainy, sometimes with substantial snowfall, but the snow usually melts regularly throughout winter.

Subregions and species

The lack of spruce north of the Arctic circle (Saltfjell) and along the southwestern coast is mainly due to barriers such as fjords and mountain ranges, and planted spruce grows well north of the arctic circle as in Tromsø.

The southern limit of the Norway Spruce habitat in Norway is limited by mountains and fjords blocking the way, and also because of winters being too mild for Norway spruce near the outer seaboard along the southwestern coast. Along the southwestern coast and fjords (Vestlandet or Western Norway) is a temperate mixed forest with pine, some yew and deciduous trees (betula pendula, wych elm, linden, oak, aspen, hazel, holly) in the lowlands and more typical boreal forest at higher altitudes.

The botanically richest areas here (following the coast north to Ålesund, often the northern, south-facing shores of fjords, and patches further north along Trondheimsfjord), even if less diverse than the Oslofjord area due to migration barriers, is considered hemiboreal and might be considered as part of the Sarmatic mixed forests PA0436 or North Atlantic moist mixed forests PA0429 ecoregion. Some of the wettest areas in this region, where annual rainfall might exceed 1,500 mm and even 2,500 mm, are sometimes considered hemiboreal rainforest.

Introduced species

Introduced species include the Norway spruce, which has been planted for economic reasons in areas outside the natural range both on the southwestern coast and in the northernmost part of the ecoregion. Sitka spruce has also been planted extensively, especially near the outer seaboard, even north to Vesterålen and Harstad.

Sycamore maple was introduced to private gardens and church yards more than 150 years ago, and has spread profusely along the southwestern coast, along the central coast (Trøndelag) and, to a considerably lesser degree, north to Vesterålen. It is still most common near cities and villages, but seems certain to continue expansion along the coast and fjords.

There are many smaller introduced plants spreading, such as rosa rugosa. However, due to the often steep terrain, forestry has been somewhat limited in the coastal area, and many areas with original vegetation remain, but are often fragmented, especially so in the southern part of the ecoregion. American mink, originally escaped from fur farms, has colonized the whole country, and threaten sea bird colonies in some areas, but have not reached the outermost islands such as Røst, which have the largest sea bird colonies. The native otter seem to be dominant in areas with competition.

Boreal rainforest

Within this long area is a smaller area classified as boreal rainforest based on botanical criteria. Much of the original forests have been destroyed, but a total of 250 forested areas, most of them not very large, have been classified as boreal rainforest. They are located from 63°20'N in Snillfjord in Sør-Trøndelag county and north along the coast to 66°N in Rana in Nordland county, but restricted to areas with high humidity; often shielded from the sun most of the day. Some inland locations are included; these are located in moist locations, often near waterfalls. This is the main area in Europe for boreal rainforest and Norway thus has a special responsibility for preservation. This coastal forest is mostly found at the lower elevations (below 200 m).

Botanical criteria for boreal rainforest

Due to the long history of human settlement (millennia) with agriculture and more recently forestry management, only fragments remain of the original forest. The boreal rainforests are made up mostly of Norway Spruce (Picea abies) but also included deciduous trees. Common Juniper (Juniperus communis) is also common. There is a rich understory of mosses and ferns. However, the most distinguishing feature is the diversity of lichens, some of which are endemic for this forest, or have their only location in Europe here (they are often found on the northwest coast of North America). Approximately 15 of the most rare or typical species of lichens have been named Trøndelagselementet (named after the Trøndelag region). Pseudocyphella crocata, Pannaria ahlneri and Erioderma padicellatum and Lobaria halli are examples of lichens. More than 60 unique species of lichen and moss can be found in the area.

There are two subtypes of this rainforest; the Namdalen type and the Brønnøy/Fosen type. There are also broadleaf trees scattered in this forest, especially in the Brønnøy/Fosen type. Broadleaf trees include birch (Silver Birch Betula pendula and Downy Birch Betula pubescens), European Rowan (Sorbus aucuparia), Aspen (Populus tremula), Goat Willow (Salix caprea), and Grey Alder (Alnus incana). Rarer species are Wych Elm (Ulmus glabra), Common Hazel (Corylus avellana) and Black Alder (Alnus glutinosa) (the latter only in the southern part of the area).

Fauna

There are a large number of species of migrating birds in this ecoregion, as well as some that stay all year. Larger herbivore animals are moose and red deer (the latter only south of the Arctic circle), as well as the smaller roe deer. Reindeer might occasionally come down to the coast north of Trondheimsfjord, but they usually stay at the highlands outside this ecoregion. Predators are few, as they have been hunted by man for centuries, exterminating brown bear and grey wolf in the coastal area. In some areas, they roam further inland in the taiga ecoregion, and might on rare occasions get closer to the coast. Red fox and the sea eagle are common predators in the area, the latter now being very common after decades of protection. There are also some lynx, mostly in the northern part. Hares, otters are common and one can even see european beavers although more rarely. There are also some amphibians including the common frog and the smooth newt; the european viper can be seen south of the Arctic circle.