Ecoregions

Atlantic mixed forests

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Atlantic coastal forest along the Normandy coast. @ C.Michael Hogan

The Atlantic mixed forests ecoregion includes coastal vegetation formations of dunes and heathlands with vegetation that thrives in salty soil. Sand dune systems occur along the southwestern coast of France, the region known as Les Landes, covered by both natural and planted forests of maritime pine (Pinus pinaster). They are rich in plant life, and home to a number of endemics. Bird diversity is particularly high--over 440 species have been recorded in the Netherlands alone. Most of the ecoregion’s mammals are widespread in other parts of Europe. Several are listed on the International Union for Conservation of Nature and Natural Resources Red List, including otter, European mink, and several species of bat. Only fragments of natural vegetation remain in this ecoregion, as most of the area was converted long ago into intensive agriculture or pasture.

Location and General Description

This ecoregion is located at the western coast of the Eurasian continent. The eastern limits are determined by the progressive disappearance of oceanic species and the appearance of continental species. Long-term human activities have wiped out most evident signs of natural forests, so it is difficult to establish a definitive biogeographic boundary. The topography consists of flat and undulating lowlands except for the hills of Brittany. Sand dune systems occur along the southwestern coast of France, the region known as Les Landes. These dunes are covered by both natural and planted forests of maritime pine (Pinus pinaster). Rich in plant life, they are home to a number of endemics

caption Refuge Naturel de la Marache à Lasne, Brabant Wallon. Source: Pol Califice / RNOB Brabant Wallon

Temperature variation and precipitation levels are not limiting factors to biodiversity. Mean annual temperatures are between 9° and 12°C from north to south, and annual precipitation ranges from 700 to 1000 millimeters (mm). Soils are generally acidic in sedimentary basins, and on hercynian crystalline bedrock in Brittany. The Loire River, the only remaining European lowland river without major riverbed regulations is found here, as are the Gironde, Seine, Rhine, Ems, Weser, and Elbe rivers at lower elevations.

Several mixed oak forests are also found in the ecoregion, dominated by Quercus robur and Betula pendula, or Q. robur and Fagus sylvatica. On the coastline, heathlands with Ulex gallii occur, adapted to local ecological conditions of wind and sea spray. In general, heathlands with Ericaceae (Calluna, Erica, and Ulex spp.) have replaced natural forests. Further south, different oaks appear, including Q. petraea and Q. pubescens, but many forests are planted with Pinus sylvestris (Pinus maritimus further south) mainly on poor sandy soils.

Biodiversity Features

caption Natterjack toad (Bufo calamita), France. (Photograph by Pascal Dubois)

The Netherlands alone has recorded over four hundred and forty species of avifauna, including the threatened Ortolan bunting (Emberiza hortulana), Garganey (Anas querquedula), Snipe (Gallinago gallinago), Kentish plover (Charadrius alexandrinus), Corn bunting (Miliaria calandra), and Spotted crake (Porzana porzana). Other notable species of birds in this ecoregion include Wryneck (Jynx torquilla), Red backed shrike (Lanius collurio), Black grouse (Lyrurus tetrix), Savi's warbler (Locustella luscinioides), and Great reed warbler (Acrocephalus arundinaceus)

The mammal fauna of the ecoregion is mostly composed of species widespread throughout Europe: red deer (Cervus elaphus), fallow deer (Dama dama), Roe deer (Capreolus capreolus), badger (Meles meles), stone marten (Martes foina), and pine marten (Martes martes). Several of the mammals found in the ecoregion are listed on the International Union for Conservation of Nature and Natural Resources Red List, including otter (Lutra lutra), European mink (Mustela lutreola), and several species of bat (Rhinolophus euryale, R. hipposideros, Barbastella barbastellus, Myotis bechsteini, M. dasycneme, and M. emarginatus).

Holocene Evolution of the Ecoregion

The ecoregion has undergone considerable transformation over the prior eight to ten thousand years. The prior 8850 years have reflected vegetative changes in the ecoregion which have generally tracked orbital and sub-orbital climate variability. There was a pronounced temperature decline from 6650 BC until the Time of Christ. In particular, the climate variation from 6740 BC until 6370 BC led to an expansion of Corylus woodlands at the expense of deciduous oak woodlands. This forest transition was accentuated by the 8.2 kyr sudden cooling event and concomitant North Atlantic winter ice expansion.

Reduction in overall forest cover due to human deforestation began by the end of the mesolithic period in this ecoregion. Between 6000 and 2000 BC the Holocene Thermal Maximum is deduced to have occurred in this ecoregion, based upon pollen core records and maximum expansion of Quercus dominated woodland. These climatic correlations are clearer in northwestern France and northerly sections of the ecoregion and less clear in the more southern mid-latitudes on the coastal European continent. Since the Time of Christ the evolution of the Atlantic mixed forests ecoregion was more affected by deforestation and land cover changes due to humans than to climate variability. The inexorable human population expansion of the region has led to massive destruction of most elements of the ecosystems within the Atlantic mixed forests over the most recent two millennia.

Current Status

Only fragments of natural vegetationremain in this ecoregion, as most of the area was converted long ago into intensive agriculture (barley, wheat, sugar beets, and corn) or pasture. These agricultural lands include some of the most productive soils of Western Europe. There are several Important Bird Areas (IBAs) in the ecoregion: the Wadden Sea and Voordelta of the Netherlands, Baie de Quiberon and Archipel de Molène of France, Nissum Fjord and Ringkobing Fjord of Denmark, and the Lower Rhine area in Germany. Basses Vallées du Cotentin et Baie des Veys in France serves as an important Biogenetic Reserve as does the Waddenzee Biogenetic Reserve in The Netherlands.

Types and Severity of Threats

caption Loire River, near Saumur, Maine-et-Loire, France. (Photograph by WWF-Canon/Mauri Rautkari)

Agricultural expansion and intensification are the most serious threat affecting IBAs across Europe. Additionally, urbanization accompanied by the pollution of air, water, and soil brings increased problems. Recreation and tourism, unsustainable exploitation, development and habitat fragmentation, agricultural abandonment, and disturbance of wildlife are other major threats.

Justification of Ecoregion Delineation

This ecoregion comprises two DMEER units: the Southern Temperate Atlantic and Northern Temperate Atlantic. These units include several vegetation units from Bohn et al. These include areas of lowland to submontane beech and mixed beech forests, lowland to submontane acidophilous oak and mixed oak forests, sub-Mediterranean and meso-supra-Mediterranean downy oak forests, fen and swamp forests, as well as floodplain, estuarine, and freshwater polder vegetation in the Aquitanian Plain, Armorican Massif, Paris Basin and Netherlands.

Further Reading

  • For a terser summary of this article, see the WWF WildWorld profile of this ecoregion.
  • Bohn, Udo, Gisela Gollub, and Christoph Hettwer. 2000. Reduced general map of the natural vegetation of Europe. 1:10 million. Bonn-Bad Godesberg
  • Davis, S.D., V.H. Heywood, and A.C. Hamilton. 1994. Centres of plant diversity. Vol. 1: Europe, Africa, Southwest Asia and Middle East. WWF and IUCN, Washington DC. ISBN: 283170197X
  • Heath, M.F., and M.I. Evans, editors. 2000. Important bird areas in Europe: Priority sites for conservation. 2 vols. BirdLife International, Cambridge, UK. ISBN: 0946888361
  • IUCN 2000: The Global Redlist of Species, of the International Union for the Conservation of Nature.
  • Filipa Naughton, Jean-francois bourillet, Maria Gernanda Sanchez Goni, Jean-Louis Turon and Jean-Marie Jouanneau. 2007. Long term and nillennial scale climate variability in northwestern France during the last 8850 years. Sage Publications
  • Ozenda, P. 1994. Végétation du Continent Européen. Delachaux et Niestlé, Lausanne, Switzerland. ISBN: 2603009540
  • Wheatley, N. 2000. Where to watch birds in Europe and Russia. Princeton University Press, Princeton, New Jersey. ISBN: 069105729X

Disclaimer: This article contains some information that was originally published by the World Wildlife Fund. Topic editors and authors for the Encyclopedia of Earth have edited that content and added new information. The use of information from the World Wildlife Fund should not be construed as support for or endorsement by that organization for new information added by EoE personnel, or for any editing of the original content.

 

Glossary

Citation

Fund, W. (2014). Atlantic mixed forests. Retrieved from http://www.eoearth.org/view/article/150291

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