Korytarz ekologiczny doliny Odry pdf

Korytarz ekologiczny doliny Odry
dams on parts of the Racibórz Basin and the Wroc³aw Proglacial Stream Valley has an
influence on the existence of the wetlands, as ground inundation has been observed
upstream of those facilities. The largest complex of open peat and swampy terrains is situated
in Miêdzyodrze, in the Lower Oder Valley.
Numerous ox-bows have been preserved in many parts, both between and outside the
levees. They are highly diversified, ranging from small waterholes with an area of several
hundreds sq metres (which often periodically dry up) to reservoirs with an area of many
hectares and up to 8 km long. Most of them are eutrophic waterbodies with many plant
communities and act as important waterfowl areas.
The forests of the Oder valley create a complex of forest associations, conditioned by
hydrological factors typical of large river valleys. The are connected with reservoirs and
stagnating and flowing waters. This complex is composed of deciduous forests covering the
lower terraces of the river, which have significant habitat diversity and a huge variety of
plant and animal life forms. Because natural vegetation has been preserved in many fragments
and the richness of avifauna is observed, these forests can be classified among the
most naturally valuable areas in Europe.
The complex of the Oder’s humid forests covers, on the Polish side, about 18 500 ha of
the Oder valley surface. The area is vast. Inaccessibility of the terrain (periodical floods)
and classification of most forests situated between levees as water- protective forests, have
led to their extensive only management (mostly using the thinning method). For this reason
a great amount of hollowed, fallen and monumental trees have been preserved here, as well
as large areas of old-growth forests.
An especially valuable area is the zone between levees (100 m to over 3 km wide), where
forests are periodically flooded. It is overgrown by the most precious patches of forests (e.g.
lowland willow-poplar floodplain forest Salici-populetum, lowland ashelm floodplain forest
Ficario-Ulmetum campestris oak hornbeam forest), whose value is enhanced by numerous
ox-bows scattered throughout the whole area. In close proximity to the river, the riverine
forests are separated by a network of wet meadows and pastures with groups of trees and
shrubs.
Thanks to the existence of great number of versatile habitats and niches, the deciduous
forests of the Oder valley are inhabited by valuable wildlife populations. It is here, where
the highest densities of breeding birds in Polish forests were found. It is also here, where we
can find one of the largest European populations of Middle-spotted woodpecker (Dendrocopos
medius) with several hundreds of pairs, as well as nesting White-tailed eagle (Haliaetus
albicilla), Red kite (Milvus milvus) – birds included in the European Red List Of
Globally Threatened Species of Plants and Animals. Endemic population of one of the subspecies
of Carabus sp., and numerous populations of Cerambyx Longicorn (Cerambyx
cerdo) – also included in the European Red List....
From among 18 500 ha of deciduous forest in the Oder valley two areas deserve special
attention and protection (possibly in the form of national parks):
• The forests between Malczyce and Œcinawa – the largest complex (about 4000 ha) of
the best preserved humid forests in the Oder valley. Oak and hornbeam forest domi-
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