Videoreport – Mire restoration in Baltic states
22. 2. 2020
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20. 3. 2020
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Restoration of the project site Malý Bor will slow down the water runoff from the spring areas

Mapped drainage ditches

The restoration works in the region of Hartmanice will start soon with an „affair of the heart“ – literally speaking – if you check the site Malý Bor on a map. There used to be a small settlement with dozens of people, a glass grindery and a sawmill. In the Iron Curtain period, the original residents were replaced by soldiers and tanks. When the military area of Dobrá Voda had been abandoned, nothing happened for quite a long time…
The only remnants from the old good times were two raceways on the Křemelná river, which are either dry or covered by vegetation, and completely non-functional.
The soldiers built 5 concrete bridges over the streams and channels (most probably for enabling tanks to pass) and more than 3 kilometers of drainage ditches that spike the spring areas and let the water run off by a straight deep way. And as a result?
Streams vanished without a trace, deviated to deep drainage ditches, heavily damaged spring areas and original minerotrophic peatlands (bogs) dried out, covered by birch and poplar.
The area of valley peaty meadows was minimalized and the meadows have dried out, (too). They are mainly covered by carex brizoides which does not allow any other vegetal species to coincide in the same biotope. Fortunately, the adjacent mire – pinus rotundata dominated valley raised bog – was not affected by the abovementioned degradation process. Thanks to its biological quality and well-preserved state, it was classified natural (or formerly known as first) zone of the National Park.

For detailed information about Malý Bor click HERE.

 

                                    What will happen this summer on the Malý Bor LIFE site? Keep on reading … ↓

 

 

Drained spring at Malý Bor site

What do we plan to do?

This year, we would like to restore the entire spring slope of the site above Křemelná river, the original alpine creeks included. Moreover, we count on rewetting the minerotrophic mire (peaty meadows and birch bog forests). The restoration principle is relatively simple. It is necessary to block all functioning artificial drainage ditches (there are more than 3 km of them) and to return streams to their natural form, with shallow and wide beds. One of the methods to block the ditches is to install transverse wooden dams and then refill the channels with soil and natural materials, including the stream banks. Particular attention will be paid to the crossings of restored streams with drainage ditches. Such places are very vulnerable and technically complicated, therefore double wooden dams will be used (instead of simple ones) and the channels will be completely filled, not only to 2/3 of their volume (which is the regular measure), to prevent water from coming back and continue the erosion.

 

 

What do we expect?

Rare raised bog with pinus rotundata

The continuous runoff, unnaturaly fast and smooth, from the spring areas will cease. It will inevitably result in rewetting of the spring areas, with natural and therefore very slow runoff. The blocked ditches will be very soon colonized by mire vegetation – sphagnum mosses, sedges and rushes – and suddenly, a new biotope will emerge. Due to gentle runoff, the groundwater level will also rise, which will automatically lead to natural loosening of dense self-seeded tree stands. On those newly created spaces, open to sunbeams, the wet mire fens with spring areas can regenerate. To sum up: A small piece of land will keep a great amount of water and will provide a new biotope for mire community of rare species.

 

What will you see?

The shrubs and self-seeded trees are already being cut along the channels to facilitate the actual commencement of restoration works. The implementation of restoration measures as such should begin in July and should be finished before the winter starts. The restoration works will be partly provided by light machinery because the site was drained to such extent that the excavators can work there without sinking. In this particular case, the use of light machinery is very helpful in blocking the deep drainage ditches. The most of restoration measures will be concentrated around the channels which are in some places 2 metres deep. On the other hand, the restoration of the mountain streams is a very delicate work. The principal aim is to return the streams to their former meandring beds, recovering their natural form and especially dynamics. This means they return to the form of shallow streams (approximately 30–40 centimetres deep), with unconsolidated banks and natural geomorphology of the bed, including various pools and still water areas in the meanders as well as shallow, fast-flowing sections between them. It is quite simple to recreate the natural bed; if it already exists, no invasive measures will be done, it will just be left to Nature. In other cases, the turfs with vegetation, covering the stream banks, will be ripped away either by excavators, or manually, and again, the rest will be left to its own succession.

 

See the gallery of photos from Malý Bor ↓
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