Location and General Description
The Central European mixed forest ecoregion consists of lowland to submontane acidophilous oak and mixed oak forests, mixed oak-hornbeam forests, as well as lowland to submontane hemiboreal and nemoral pine forests on the North European glaciated plain. It is bordered by the lowland-colline subcontinental meadow steppes and dry grassland vegetation on the eastern side, hemiboreal spruce and pine-spruce forests to the north, beech and mixed beech forests of the Carpathians to the south, and the beech and mixed beech forests of the Baltic and Western Europe to the west.
The ecoregion consists of vast plains in the middle, hilly moraines with lakes in the north, and upland areas in the south. The highest elevation within the region does not exceed 600 m, and most of the area lies between 100 and 300 m above sea level. Mean annual temperatures are quite uniform throughout the region and range between 7 and 9°C; the climate is more mild in the west and more continental in the east. The mean January temperatures range from -1°C in Germany to -6°C in Belarus. Annual precipitation is between 500 and 700 mm; most of which falls during the growing season, with maximum rainfall in July. Snow cover in the NE part of the region lasts over 3 months, but the accumulation of snow is not very high; in the south and in the west of the region snow cover in winter is ephemeral.
The percentage of forested area as well as the forest composition varies among countries of the region.
Country % of forested area % of broadleaf stands
Czech Republic 33.3 21.8
Germany 28.9 33.1
Poland 28.0 22.5
Belarus 30.2 30.0
Ukraine 15.9 43.0
The mean forest cover in the entire region is now below 30%, and most of that is either secondary forest or forest plantations. Scots pine (Pinus sylvestris) is now the most common forest tree species of the eco-region. Formerly it used to be confined to less productive habitats, primarily sandy soils in areas of low precipitation. Due to extensive planting in 19th and 20th centuries it is now widespread throughout the region, even in more fertile habitats. At the regional scale it covers now about half of the total forest area, and locally – like in western Poland - it can constitute up to 90% of forest stands. The deciduous and mixed deciduous forests have been decimated, primarily due to the fact that that they used to occur on habitats suitable for agriculture. That refers especially to the lowland mixed deciduous forests (Quercus robur-Carpinus betulus-Tilia cordata), which now cover less than 10% of their original range. Mixed deciduous forests in the western part of the region (Germany, Czech Republic, W Poland) contain an admixture of European beech (Fagus sylvatica), or even small pure beech stands. In the north-eastern part of the region (Lithuania, Belarus, NE Poland) Norway spruce (Picea abies) occurs as an admixture in mixed deciduous stands on fertile habitats, often as a canopy emergent. This is especially pronounced in the Bialowieza Forest, where the old-growth spruces in good habitats can exceed the height of 50 m, they are the tallest trees in North European lowlands. Waterlogged sites are dominated by black alder (Alnus glutinosa), and to a lesser extent by downy birch (Betula pubescens) and various species of willows (Salix spp.). The former poplar (Populus sp.) and elm (Ulmus laevis) forests on river terraces has been largely replaced by willow (especially Salix purpuraea) thickets
The whole ecoregion belongs to the most densely populated and altered parts of Europe. Much of the original vegetation – which used to be mostly forests – was long ago transformed into arable fields, meadows, and pastures. That transformation created a range of semi-natural habitats (like extensively used meadows and traditional pastures) which now harbour a vast part of plant and animal species diversity. That diversity is now largely threatened by the changes in land use pattern, namely by more intense management in some areas, and abandonment of traditional management (associated with secondary succession) in others. The forest cover in the entire region is now slowly increasing at the expense of arable land. However, some of the forest habitats have been dramatically reduced and altered. This refers especially to the riparian forests on river terraces, which have been mostly wiped out and replaced by meadows, pastures or willow plantations. The remaining riparian forests are prone to biological invasions, and their ground vegetation layer is now dominated by a few very expansive alien plants. Also mixed deciduous oak-hornbeam forests have been reduced to a tiny fraction of their original distribution range.
The famous Bia?owieza Forest, located just in the middle of the eco-region on the border between Poland and Belarus, is one of the largest and definitely the best preserved forest tract in the lowlands of Europe. It still contains a wide array of old-growth forest stands representing all the major habitat types, a rich variety of wildlife and a still not sufficiently studied numerous lower plants, fungi and slime moulds.
One of the most distinct features of the ecoregion is the presence of extensive wetland habitats. Common in early mediaeval times, they have since largely disappeared because of intensive draining of marshes and river valleys. Two complexes of marshes, peat-bogs and fens – the Polesie region on the border between Belarus and Ukraine, and the Biebrza valley in the NE Poland – are now among the largest remaining tracts of semi-natural wetlands in Europe. They provide habitat for numerous rare and endangered species, especially birds. The Biebrza valley is now protected within a national park (the largest one in Poland), while the wetlands of the Polesie region are, for the most part, not protected in any way.
Due to the past glaciation, relatively uniform topography and lack of distributional barriers, the flora of the region does not have any endemic plant species. An interesting phenomenon, however, is the occurrence of numerous boreal plants, relicts of the early post-glacial vegetation. These species include, among others, cloudberry (Rubus chamaemorus), and dwarf birch (Betula nana). This group of species is restricted to the northern and north-eastern part of the region. Another distinct feature of the flora of the Central European mixed forests is the presence of thermophilous plant species typical of warmer and drier habitats, particularly in the south-eastern part of the ecoregion, which borders the forest-steppe zone of Ukraine, Moldova and Romania. In the rest of the region thermophilous plant species occur mostly in open and semi-open habitats created by traditional ways of land-use (grazing and burning), and are now largely threatened either by secondary forest succession or by ongoing afforestation works.
Rare and endangered species of the region enjoy legal protection, however often the protection of their critical habitats is not sufficient. This is especially true for most of the species – plants and animals alike – associated with wetland habitats like wet forests, peat bogs and fens. Many species (such European hare, partridge, and several ancient weed species), which used to be very common in times of traditional land management, are now declining due to more intensive forms of management being implemented in agriculture.
Depending on the country, between 20-50% of mammals and 15-40% of forest dwelling birds are categorised as threatened. European bison (Bison bonasus)was rescued from a severe bottleneck of only 12 individuals. It is now the only large grazer left in the region, but it’s numbers are still too small to fill this lost ecological niche. Due to its habitat and spatial requirements may serve as an umbrella species for other endangered animals. At the moment its numbers and spatial distribution do not guarantee the survival of self-sustainable population. Within the eco-region, free ranging herds are present only in few localities of Poland, Byelorussia and northern Ukraine.
The spatial structure and population status of lynx (Lynx lynx) are not very well recognised. Generally present in few scattered, isolated sub-populations. Population numbers are on decline, threatened by habitat loss and fragmentation, very sensitive to human-related disturbance, with different legal status in countries of the region. Its high requirements regarding the size of home range and remoteness of core habitat make the species a very good indicator of the quality of an environment.
Two eagles in these forests deserve mention. The white-tailed eagle (Haliaeetus albicilla)is the most spectacular raptor of lowland forests in Central Europe. Its core range in the region covers north-eastern Germany, northern Poland, western Byelorussia and Baltic countries. Optimal nesting habitat requires combination of vast forest complexes and vicinity of lakes or rivers. Its numbers within the eco-region probably do not exceed 2000. The nesting area of the greater spotted eagle (Aquila clanga) is limited to eastern Poland, part of Byelorussia and Ukraine. Strongly associated with old growth forest bordering with wetlands. Threatened by the loss of habitat, mortality connected with power lines, and poaching along migration routes in south eastern part of Europe.
Black grouse (Tetrao urogallus), the largest European woodland grouse, is quickly disappearing due to the loss of habitat and over-hunting. In Central Europe it presently occurs only in few scattered, completely isolated populations, leaving it extremely vulnerable to inbreeding. Nesting and breeding require vast timber stands not disturbed by man. Its successful rehabilitation requires an active breeding and conservation program.
Other threatened mammals include pond bat (Myotis dasycneme), barbastelle (Barbastella barbastellus), wolf (Canis lupus), steppe polecat (Mustela eversmannii), and spotted souslik (Spermophilus suslicus). Other threatened birds include lesser kestral (Falco naumanni), corncrake (Crex crex), and aquatic warbler (Acrocephalus paludicola).
About 75% of the original Central European mixed forest cover is estimated to be lost. Pristine and relic stands of this forest type are believed to have been eliminated completely except in the Bialowieza Forest in Poland and Belarus. At the European level, only about 6.3% of forests have protected status, and among mixed broad-leaved forests only 1.3%. On average, 95% of European protected forests are fragments smaller than 10 sq. km. None of the 20 largest forest protected areas in Europe are situated within the Central European mixed forest ecoregion.
The native mixed forests that once dominated the region have been gradually replaced during last two centuries, mostly by Scots pine monocultures. There is a general tendency towards an increase of forested area in the region, and the formerly widespread extensive forest management has been gradually replaced by intensive measures. According to a crown condition survey, high defoliation scores were reported for Scots pine in the Czech Republic, southern Poland and Belarus, for spruce in Czech Republic, and for beech in Germany.
Types and Severity of Threats
In many cases, legal protection does not preclude threats. Logging is a common practice in the majority of European national parks and regular hunting takes place within many protected areas. Other threats include: air, soil and water pollution, increasing urbanisation, and intensive forest management, particularly large size clear cuts reforested with coniferous monocultures. Forest habitats are often fragmented by divided highways and multi-track railroads, creating barriers to wildlife movement.
Justification of Ecoregion Delineation
This ecoregion is equivalent to the DMEER unit of the same name. It consists of the lowland to submontane acidophilous oak and mixed oak forests, mixed oak-hornbeam forests, and lowland to submontane hemiboreal and nemoral pine forests on the North European glaciated plain. It is bordered by the lowland-colline subcontinental meadow steppes and dry grassland vegetation on the eastern side, hemiboreal spruce and fir-spruce forests to the north, beech and mixed beech forests of the Carpathians to the south, and the beech and mixed beech forests of the Baltic and Western Europe to the west (Bohn et al. 2000).
Bohn, Udo, Gisela Gollub, and Christoph Hettwer. 2000. Reduced general map of the natural vegetation of Europe. 1:10 million. Bonn-Bad Godesberg
Dr Kajetan Perzanowski – International Centre for Ecology, Polish Academy of Sciences
Dr Jerzy Szwagrzyk – Department of Forest Botany and Nature Conservation, Agricultural University of Kraków
Prepared by: Dr Kajetan Perzanowski – International Centre for Ecology, Polish Academy of Sciences
Dr Jerzy Szwagrzyk – Department of Forest Botany and Nature Conservation, Agricultural University of Kraków