Sand dune - Country Report, Finland

Status: Original text revised 2008 with redrawn map; Authors: Pirjo Hellemaa & J Patrick Doody,

This article on the sand dunes of Finland, is a revised country report from the 'Sand Dune Inventory of Europe' (Doody ed. 1991) . The 1991 inventory was prepared under the umbrella of the European Union for Dune Conservation [EUDC]. The original inventory was presented to the European Coastal Conservation Conference, held in the Netherlands in November 1991. It attempted to provide a description of the sand dune vegetation, sites and conservation issues throughout Europe including Scandinavia, the Atlantic coast and in the Mediterranean.

An overview article on the distribution of European sand dunes provides links to the other European country reports. These represent chapters from updated individual country reports included in the revised, 2nd Edition of the 'Sand Dune Inventory of Europe' prepared for the International Sand Dune Conference “Changing Perspectives in Coastal Dune Management”, held from the 31st March - 3rd April 2008, in Liverpool, UK (Doody ed. 2008).

Introduction

There are large areas of dune landscapes in Finland, mainly formed from eskers. A high proportion of these are not directly associated with the coast. These occur in three basic situations: peri-glacial dunes; postglacial beaches, developed on a rapidly rising coastline and modern coastal dunes. All three may show Aeolian activity producing typical dune forms. However, for the purpose of this inventory only those dunes of recent coastal origin have been included. There are in excess of 1,300ha of coastal dune in Finland.

Distribution and type of dune

The modern sand dunes of Finland have formed on a coastline, which is rising at a maximum rate of 8mm per year relative to sea level. Typically, modern coastal dunes have formed only over the last 1,000 years. Prior to this, though sandy beaches developed the climate was too wet for Aeolian dunes to become established. The main dune areas occur in the Gulf of Bothnia, where strong wave action affects the shores. The surface deposits are largely composed of sand and have flat sandy beaches in places with dunes behind them (Hellemaa 1998) . A few scattered and smaller sites occur in southern and south western Finland where land uplift has led to the creation of successive beach ridges on sand and gravel shores, but dunes are poorly developed.

Because of their development on a rising coastline, the dunes are generally prograding. The ridges establish as a sequence lying ‘parallel’ to the coast and are sometimes interspersed with damp hollows. They are never high, usually up to 8m, though in the south, where the rate of uplift is slower, dunes may reach 20m, especially at the forest edge where wind speeds are slower. The dominant type of vegetation includes acid loving species; the calcium carbonate content of the sand is low because of the acidic nature of the bedrock.

File:Finland.jpg

Figure: Map of sand dune distribution and important sites in Finland. Copyright: J Pat Doody

Vegetation

Historically, though the natural vegetation is forest, grazing helped create open dune grassland and heath. Today the absence of grazing at all sites has allowed a reversion to reed bed and woodland, with pine, birch and alder. In some areas human trampling, tourism and military activity keep beaches open, though intensive use can impoverish the flora. Where a full sequence of vegetation is present, the most usual succession begins with sand banks as outlined below.

Strandline

Honckenya peploides, which often occurs as a carpet, dominates the upper shoreline together with binding embryonic dunes. Cakile maritima and Lathyrus japonicus are also frequently present;

Foredune

The main dune building species is Leymus arenarius, although Ammophila arenaria does occur in the south at one small site (Lappvik);

Dune grassland

Dunes bound by herbaceous vegetation are usually acid dune grasslands dominated by Deschampsia flexuosa. Festuca rubra and F. ovina are also frequent, though in the south, at Tulliniemi, F. polesica and Carex arenaria replace them. Hieracium umbellatum, Rumex acetosella. Mosses and lichens are always present in a sparse grass cover;

Dune slack

A continuous carpet of mosses covers the sand when the ground-water table is near the surface. Carex spp., Juncus spp. and Salix spp. together with Phragmites marsh occur in the wetter areas. There are also coastal lagoons and transitional mires;

Dune heath

Empetrum nigrum is the most important species and binds small dunes, although Salix repens can also form small dunes. Juniperus communis, Salix phylicifolia, Arctostaphylos uva-ursi, Juncus balticus and sometimes Myrica gale may also be present;

Scrub

Salix, Betula and Alnus bushes are usual in dune valleys.

Woodland

Invasion by pine forest (Pinus sylvestris) is usual in Finland today. Prior to this, open vegetation was maintained by the grazing domestic animals. Other species include Prunus padus, Betula spp. Sorbus aucuparia and Alnus spp., as well as Salix caprea and Picea abies at Yyteri.

Important sites

The map opposite (Figure 07) shows the location of sand dune sites in Finland. The site numbers in italics and brackets are those included in the report by Hellemaa (1998).

The more important sites listed in the table below include coastal dunes near or above 50ha. On a European scale all, the coastal sand dune areas, except Vattaja are small. For several of the sites the sand dunes form part of the European Union, Natura 2000 network.

Figure 07 Sand dune distribution in Finland

File:Finland Table.jpg

Figure: List of important sand dunes sites in Finland.

(N) north coast, (W) west coast, Pt. partly, Natura 2000, belongs to the EU Natura 2000 network, see http://ec.europa.eu/environment/nature/natura2000/index_en.htm. NR, Nature Reserve; MA, Military Area; (*) Esker protection area, building is regulated.

The actual area of sand dune given here only includes the open beach. Each of the systems is much larger, for example, Kalajoki is 10,000ha and the protected Natura 2000 area at Vattaja is 1,200ha. Forest covers most of this area and has no connection with the present coast, because of the rapid rate of isostatic uplift.

Since the first inventory, new sandy areas have risen above sea level and dunes grown higher in many sites. Marine erosion has worn scarps in the dunes during winter storms, especially at Vattaja.

A detailed report of the sand dunes of Finland has been published (Hellemaa 1998). In the first phase of the research, all sandy seashores marked on the Basic Map of Finland, scale of 1:20,000, excluding islands and inland waters, were identified. All these shores were visited in summer 1987, together with all the sites described by Lemberg (1933-35) located in present-day Finland. Twenty-eight sites were then chosen for closer research on the grounds of their evidence of Aeolian activity. The history of these coasts was studied by comparing their present state with historical records, especially the above-mentioned data collected by Lemberg, and by examining maps and aerial photographs of different ages.

The island of Hailuoto consists largely of glaciofluvial sand, reworked and built into numerous parallel beach and dune ridges on the western and north western coasts, some with intervening lagoons and marshy swales. The south western coast of this island has parabolic dunes that have advanced toward the northeast, and the prograding sandy northern coast has numerous emerged beach ridges formed by wave and wind action, surveys of their levels in relation to land uplift showing that they formed at intervals of about 23 years (Alestalo 1979). Pine forest has separated the parabolic dunes from the beach and the area of open beach at the western and south western coast of Hailuoto is now only about 60ha.

Conservation

There are two major influences on the sand dunes of Finland, firstly the direct destruction by tourist development and secondly the reduction in grazing pressure. The building of summer cottages, which is one of the major manifestations of recreational activity, has adversely affected many sites. The Yyteri dune system, formed on an emerging esker, is the only site where there are no separate Empetrum nigrum dunes. It is also the only site, which with no grazing by domestic animals. As a result grazing pressure, which has prevented forest invasion, is important for the development of this habitat type and is vital for insects that need moving sand and live on E. nigrum, such as the small butterfly Scythris empetrella.

The open coast between Siikajoki and Kokkola is composed of sandy beaches and dunes, which have formed beside the esker chains at Siikajoki, Kalajoki, and Lohtaja. The long sandy beach at Lohtaja is backed by partially vegetated dunes. The dunes arise from emerging beach deposits. The mobile dunes at Kalajoki and Lohtaja advanced by 0.5-1 m/yr during the 18th and 19th centuries, but were arrested once grazing and clear felling were discontinued and the deflation surface began to be colonised by forest.

It is not clear how the re-invasion of pine is viewed, as it could be argued that it is simply taking the dunes back to a natural stage in their development, before humans introduced grazing animals. However, if the experience of other countries is any guide, pine invasion is often detrimental to nature conservation as the open and richer dune vegetation is lost. More recently, pine invasion has been most obvious in Monäs. The foredunes (14ha), are more or less the only open dune. At the same time the dunes have grown higher and some new saltmarsh has formed. Rosa rugosa, which can become dominant in the absence of grazing and has done so in other countries, is not widely regarded as a weed, except at one site.

Additional information on the spider fauna see, Perttula (1984).

Contact: Pirjo Hellemaa, Department of Geography, P.O. Box 4, FIN-00014 University of Helsinki, Finland.

Additional information

Cramer, W., 1993. Dry coastal ecosystems of the Northern Baltic. In: Ecosystems of the World 2A Dry Coastal Ecosystems, Polar regions and Europe, ed., van der Maarel, Elsivier, 98-100.

For information on spiders see, Almquist (1973)

See also

• Sand Dunes in Europe
• Articles on sand dunes on Wikpedia
• European Sand Dune Distribution
• Sand dune types - Europe

The main author of this article is Doody, Pat Please note that others may also have edited the contents of this article. Citation: Doody, Pat (2009): Sand dune - Country Report, Finland. Available from http://www.coastalwiki.org/wiki/Sand_dune_-_Country_Report,_Finland [accessed on 25-11-2024] For other articles by this author see Category:Articles by Doody, Pat For an overview of contributions by this author see Special:Contributions/Pat Doody