Document Actions
Forest hydro-technical amelioration
Up one level
3.7. Forest hydro-technical amelioration
Main forms of forest hydro-technical amelioration used in the basin are bog reclamation with the aim of further afforestation and drainage of swampy forests to increase the forest stand productivity.
The drainage (reclamation) is accompanied with the lowering of the ground water table, accelerated evacuation of thaw and rain water, change in water and air regimes of peat deposits, and leads to the transformation of the forest plant communities in which adverse impact on biological and landscape diversity predominates. Very often, although not always, an economic effect is also achieved in the form of additional timber harvest.
Large-scale draining of the basin forest lands and marshes was launched in the Belorussian and Ukrainian Polessye in the second half of the 19th century by the Western expedition led by I.I.Zhylinsky. The major scope of work related to draining was performed in the 1960-1970s. By now, 438.6 thousand hectares of the basin forest reserve have been reclaimed by draining (including 155.3 thousand hectares in the Belorussian part of the basin, 201.1 thousand hectares in the Ukrainian and 82.2 thousand hectares in the Russian ones).
Draining causes a change in the whole set of factors determining the habitat conditions for forest phytocoenoses (plant communities): the existing wetland and forest communities are rearranged, the natural succession of forest and wetland phytocoenoses is interrupted, anthropogenic post-amelioration successions are initiated, the composition and reserves of phytomass are transformed. Some other changes linked with the construction and operation of forest hydro-technical amelioration systems take place as well.
The above changes bring about consequences unfavorable for the fauna, flora and landscape diversity of the basin, such as:
- death, displacement and suppression of populations of the majority of hygrophilous species existing prior to amelioration (including rare and endangered ones);
- destruction of the native wetland community in general, its disappearance from the existing landscape mosaic and replacement with the forest one;
- extinction of feeding reserves for birds and animals that need wetlands and marshes at different periods of their life;
- degradation of berry-fields (cranberries, bog whortleberries, cloudberries, red bilberries);
- higher probability of unpredictable collapse of new communities under the extreme conditions of anthropogenic and natural origin;
- interruption of the natural dynamics of wetland and forest-marshland communities;
- higher probability of developing degressive successions when forest and wetland species are supplanted by weed and invasive species;
- cessation of peat formation;
- release of greenhouse gases into the atmosphere caused by progressing peat decomposition;
- higher fire risk in the areas of reclaimed (dried) peat mines ;
- deteriorating condition of forests on the adjacent lands resulting from the passive drainage of areas adjacent to the sites under forest hydro-technical amelioration, which in some cases causes the outbursts of forest pests populations and the development of forest diseases.
Among the positive outcomes are:
- increasing amount of forests and expanding forest areas;
- creation of favorable conditions for the integrated development of forest species;
- increased ecosystem productivity due to the growth in reserves of all components of tree mass;
- emerging of specific biotopes of open peat areas;
- appearing of numerous water biotopes (channels, drains, water bodies, etc) conducive for the diversification of aquatic and littoral species.
Previous:
Fires