EXECUTIVE SUMMARY - UNESCO World Heritage

Geology and geomorphology
Th e area’s characteristic landscapes evolved
about 20,000 years ago during the second
major glacial advance period of the Vistula
Glaciation. In terms of geomorphology, the
nominated property is part of the garlandshaped
terminal moraine bend of the Pomeranian
Stage (HOHL 1985, BAUER 1972).
Th ere are height diff erentials of up to 40 m,
with a multitude of smaller and larger
hollows and summits the slopes of which
being inclined up to 25 degrees.
Climate
Mean annual precipitation is just below
600 mm. More than 50% of the precipitation
occurs within the growth season, with peak
values in June or July. Th e annual mean air
temperature is 8.0°C. Th e predominant
wind direction is west to southwest with
maximum storm activity in February.
Soils
Serrahn is part of the Chorin moraine complex
of the Wismar type. Th e diversifi ed
mosaic of ground forms of the terminal
moraine is determined by ground water-free
mesotrophic sandy soils which predominantly
occur as weakly podzolised brown soils
and are found associated with strong soil
forms of carbonate-containing boulder
clays (Albelusivols with clay). Fault blocks
of boulder clay and boulder marl are found
surfacing in places or are concealed below a
sandy layer. Local agglomerations of coarse
terminal moraine material represent remains
of alluvial deposits which were intensely
exploited by quarrymen in earlier times.
Having developed with the thawing of
buried dead ice relics, the mostly drainless
hollow forms are characterised by Holocene
peat formations on siliceous and organogenic
peat clays. Consequently, the nominated
property contains kettle-hole mires of poor
trophic conditions. Soils under hydromor-
phic infl uence are found on the banks of the
Schweingartensee (buff er area) in the shape
of gley podzoles and gley brown soils with
spring-time groundwater levels above 1 m
underground.
Water balance
Th e water bodies in the nominated property
were devoid of any above-ground effl uents
in their former natural condition. Over
the past decades, the artifi cial drainage was
eliminated within the scope of renaturation
measures. Th erefore, hydrologic conditions
have largely normalised. Atmospheric
humidity in proximity to the sea and nearby
the kettle-hole mires is increased at a small
scale, resulting in elevated numbers of
humidity indicators among the vegetation.
Th e capacity to retain water in the nearsurface
sand layers is mostly low. 20–25%
of the water volume will rapidly drain away
deeper into the ground and ducted through
an underground drain to the eastern border
of the property right up to the Schweingartensee
in the buff er zone. Water supply
is better only such areas that contain layers
of boulder marl and clayey sand covers.
2. DESCRIPTION
Kettle-hole mire (Serrahn)
with Sphagnum (spec.) and
Calla (Calla palustris)
Geology:
Pleistocene formations
Climate:
Atlantic-Subcontinental
Soil:
podzolic brown soil, gleyic
brown soil, gleyic podzol,
bog soil
Predominant beech
forest types:
Luzulo-Fagetum
Galium odorati-Fagetum
Nationale
Naturlandschaften
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