Environmental Archaeology

Celtic broadleaf forests

September 14, 2012, 12:52 pm
Content Cover Image

Crow Wood, Kincardineshire, Scotland. @ C.Michael Hogan

The Celtic broadleaf forests occupy the majority of the land area of Ireland, and are chiefly situated on the eastern portion of this island; this ecoregion type also occupies the greater part of England, extending over the northern and central portions of England, southwest of England, and even the south and east of Scotland.

There is no vertebrate endemism of this ecoregion, owing to the recent migration of all such taxa to the British Isles following the most recent glacial maximum.

Forests of this ecoregion have been significantly degraded beginning with agriculture in the mid-Holocene and continuing to present time with poor forestry management that has encouraged widespread use of alien species conifer plantations. 

Location and general description

The Celtic broadleaf forests occupy the eastern part of Ireland; the vast majority of Wales; extreme southwest of England, including Cornwall and Devonshire; central and northern England; and the south of Scotland extending along the North Sea coast through most of Aberdeenshire and Morayshire. In phytogeographic parlance, this ecoregion, as well as all of Ireland, lies within the Atlantic European province of the circumboreal region, and considered in the Boreal Kingdom.

The climate of this ecoregion is generally mild, but associated with a large percentage of precipitation days and persistently high dampness. Climate in this palearctic region is tempered by the presence of the Gulf Stream lapping at the west of the British Isles.

Biodiversity

In terms of native vertebrates there are a total of 257 recorded species in the Celtic broadleaf forests ecoregion. It is not surprising that there are no endemic vertebrates in the ecoregion, since all vertebrate taxa here populated the region by migration from the European continent only since glacial melting following the close of the most recent ice age, roughly 10,000 years before present.

caption The Near Threatened Bechstein's bat. Source: Dietmar Nill Threatened non-endemic mammalian taxa in the ecoregion are: the Near Threatened Bechstein's bat (Myotis bechsteinii), the Near Threatened European otter (Lutra lutra) and the Near Threatened western barbastelle (Barbastella barbastella)

There is a single Special status non-endemic native reptiles of the Celtic broadleaf forests: the Lower Risk grass snake (Natrix natrix)/

Special status native non-endemic avian species here are: the Near Threatened black-tailed godwit (Limosa limosa), the Near Threatened Dartford warbler (Sylvia undata), the Near Threatened Eurasian curlew (Numenius arquata), the Vulnerable greater spotted eagle (Aquila clanga) and the Near Threatened red kite (Milvus milvus).

Status

caption Broadleaf forest at Red Moss, Aberdeenshire. @ C.Michael Hogan Approximately ninety percent of the ecoregion habitat has been destroyed, generally over the last five thousand years, due to agricultural land conversion and deforestation. The net outcome is an ecoregion which has not only lost most of its pristine cover, but which has been heavily degraded by fragmentation. While the United Kingdom has been a leading nation in habitat protection plans beginning about a century ago, extensive damage has already been inflicted on these forest areas.

Many of the best preserved relict forest stands of the ecoregion are in riparian zones and swamp forests such as associated with the mosses (bogs) of eastern Scotland.

Threats

The greatest ongoing threat is a short-sighted predilection for cultivation of alien species conifer plantations, rather than widespread re-establishment of native mixed woodlands. This high density planting of non-native conifers responds to short term desires for maximum biomass of logging at the expense of habitat preservation. Correspondingly considerable ongoing topsoil loss is incurred by clearfelling of these alien stands, an outcome that also increases rural non-point sediment runoff and aggravates water pollution of the ecoregion's rivers. This chain of events not only reduces terrestrial wildlife habitat, but also degrades freshwater aquatic habitats in much of the ecoregion.

While there are certain national tax incentives for re-establishing native broadleaf woodlands, particularly in the United Kingdom, many of the poor forestry practises are generated at the local level; for example, Aberdeenshire contains suitable broadleaf habitat in large fraction of its landscape, but decisions at the council level has promoted widespread mismanagement and encouragement of alien conifer stands.

Prehistory

caption Tomnaverie Stone Circle, northeast Scotland, circa 2000 BC. @ C.Michael Hogan This region is relatively young with regard to human settlement, due to glaciation during the most recent ice age. Mesolithic peoples were certainly in evidence circa 9000 to 8000 years ago throughout the present day English portion of the ecoregion, as well as the Welsh, Irish and eastern Scotland areas of the Celtic broadleaf forests. Neolithic farmers derived, as grain farming technologies developed, along with advancing forms of livestock tending, with appearance of some of the early timberhouses such as Balbridie along the River Dee in Scotland, which dates to circa 3800 BC.

The Romans arrived to begin recorded history within the ecoregion, with major roman urban settlements commencing in the first century AD, although evidence shows indigenous Anglo-Saxon towns such as York had existed for a millennium prior. Viking settlement in coastal areas of eastern Scotland, Wales and eastern Ireland are widespread beginning at least by the ninth century AD.

Justification of ecoregion delineation

caption Celtic broadleaf forests in the British Isles. WWF The Celtic broadleaf forests is an equivalent to the DMEER (2000) unit of the identical name. This ecoregion is chiefly comprised of lowland to submontane acidophilous oak and mixed oak forests, mixed oak-ash forests in both the Republic of Ireland and the United Kingdom. The Celtic broadleaf forests also include limited extents of western boreal and nemoral-montane birch forests, fen and swamp forests, in addition to floodplain, estuarine, and freshwater polder vegetation, and the ombrotrophic mires of northern England and southern Scotland (Bohn et al. 2000). This ecoregion carries the label PA0409, as designated by the World Wildlife Fund.

References

  • Udo Bohn, Gisela Gollub and Christoph Hettwer. 2000. Reduced general map of the natural vegetation of Europe. 1:10 million. Bonn-Bad Godesberg 2000.
  • 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.
  • DMEER. 2005. Digital Map of European Ecological Regions (DMEER), Version 2000/05
  • J.P.Gasc, A.Cabela, J.Crnobrnja-Isailovic, D.Dolmen, K.Grossenbacher, P.Haffner, J.Lescure, H.Martens, J.P.Martinez Rica, H.Maurin, M.E.Oliveira, T.S.Sofianidou, M.Veith and A.Zuiderwijk, editors. 1997. Atlas of amphibians and reptiles in Europe. Societas Europaea Herpetologica & Muséum National d'Histoire Naturelle (IEGB/SPN), Paris.
  • M.J.Costello and K.S.Kelly. 1993. Biogeography of Ireland: past, present and future. Irish Biogeographic Society Occasional Publications Number 2
  • M.F.Heath and M.Evans, editors. 2000. Important Bird Areas in Europe: Priority sites for conservation. 2 vols. BirdLife International, Cambridge, UK.
  • H.Heinzel, R.Fitter and J.Parslow. 1977. Pareys Vogelbuch - Alle Vögel Europas, Nordafrikas und des mittleren Ostens. Aufl. Verl. P. Parey, Hamburg, Berlin.
  • C. Michael Hogan. 2007. Elsick Mounth, Megalithic Portal, ed A. Burnham
  • P.Ozenda. 1994. Végétation du Continent Européen. Delachaux et Niestlé, Lausanne, Switzerland.
  • World Wildlife Fund. 2010. Celtic broadleaf forests.
Glossary

Citation

Hogan, C. (2012). Celtic broadleaf forests. Retrieved from http://www.eoearth.org/view/article/51cbf4987896bb431f6aff07