RESTORATION OF WETLANDS At - wise-rtd.info

600
1700
2004 2008
Fen Orchid
(Liparis loeselii)
number of flowering individuals
RESTORATION OF WETLANDS
At eight Sites of Community Importance within the project area we
have restored the wetlands to a total area more than 600 hectares
and on a further 1200 hectares the water conditions of the forest soils
have been substantially improved. Thus the favourable conservation status
of the habitats and species targeted has been reached at a total area
over 1800 ha. Altogether more than 3 kilometres of drainage ditches of
various sizes were filled with sand and soil. Following the completion of restoration
measures, the gradual increase of abundance of typical wetland
species, including those of Community importance, was observed. Especially
in spring and summer time these sites are now virtually overflowing
with a huge diversity of life forms. Hundreds of dragonflies are flying above
the restored wetlands, often reaching far from their edges into the surroundings,
and the voices of frogs and birds can be heard from a distance.
The black storks, herons, wild geese, ducks and other waterfowl have also
re-appeared, searching for food and quiet nesting places.
120
1300
400
2800
1600
4000
2004 2008
Round-leaved Sundew
(Drosera rotundifolia)
number of flowering individuals
2004 2008
Large White-faced Darter Dragonfly
(Leucorrhinia pectoralis)
number of adults
2004 2008
Moor Frog
(Rana arvalis)
number of adults
Increase in abundance of threatened fauna and flora species within
the project area due to implementation of restoration measures
2004 - status before the project 2008 - status at the end of the project
HOW TO RESTORE THE WETLAND
When restoring wetlands, we usually do it in exactly the opposite way to when
they were drained. The unnaturally fast water outflow through the drainage ditches
has to be slowed down or, preferably, completely stopped and the water table in
the ditches should be impounded (increased). For this purpose various types of
constructions, e.g. small earth, wooden or rock-fill dams, sluice-gates, etc. can be
used. However, in the case of smaller ditches, the best solution is their complete
backfilling. Before starting with the restoration works, one has to get the approval
of the landowners and/or land users concerned, as well as all other necessary
permissions. Backfilling of smaller ditches can be done just with simple hand tools
(shovels, spades, picks, wheel-barrows), while for the larger ones usually some
construction machines have to be used, such as excavators or earth-movers.
Following the backfilling of drainage ditches the hydrological regime and the entire
ecosystem gradually return to their natural state prior to drainage. In the case of
smaller wetlands the raising of the water table can be observed within few days, in
larger ones it can take several months or even years. After many years of absence
the water suddenly appears even in the near-by springs and streams that have been
dried-up for decades. Sometimes it even springs from places where nobody would
expect it. Suddenly the air is cooler, the land (vegetation) greener. It is almost unbelievable,
how fast life returns back to the recently restored wetlands. Some species,
such as dragonflies or amphibians, can find a restored wetland within a few hours
or days, while others take much longer. Yet, sooner or later, most of the original
inhabitants reappear and wetland life returns back to its own peaceful way.
9
14
2004 2008
Black Stork
(Ciconia nigra)
number of nesting pairs
60
120
2004 2008
European Beaver
(Castor fiber)
number of individuals