Wetlands are vitally important natural areas and the most biologically diverse of all ecosystems.
Some Belarusian wetlands are more than 10,000 years old and began to form when the last glaciers disappeared from the territory of modern Belarus.
Wetlands have a number of unique features that are important to the global biosphere. They maintain an optimal level of groundwater and store large quantities of carbon. They also provide a habitat for numerous plant and animal species, many of which are unable to live in other ecosystems. Most wetlands are classified as natural protected areas (NPAs).
There are three main types of wetlands: marshes, swamps and mires (peat bogs and fens).
Peat bogs, or peatlands, are fed by water that derives mainly from rain or snow, which is low in the nutrients that are necessary for the growth of many types of plants. However, sphagnum mosses thrive in such conditions. They grow in dense, compact clusters that form large carpets. The mosses grow faster in the middle of the bog than at the perimeter and can reach lengths of 5 to 7 m. Sphagnum leaves feature large numbers of dead cells containing pores that absorb huge amounts of water. According to scientists, sphagnum stores so much water that its mass is 30 to 37 times greater than its weight. The presence of these mosses contributes to the rapid development of peat bogs. Sphagnum stems are unique in that the upper part is growing while the bottom part is decaying, and it is the accumulation of this dead plant material that forms peat.
In addition to moss, bogs also provide a habitat for low pine and birch trees. The grass-shrub layer in bogs typically comprises different types of cottongrass, dwarf birch, carnivorous plants (sundews) and berry bushes (cranberries, blueberries and even cloudberries).
A raised bog is formed where the peat builds up to a level where groundwater and surface water can no longer reach the centre of the wetland, resulting in the creation of a rain-fed bog. As the peat continues to form, a shallow dome develops over time. The microclimate of raised bogs in Belarus is very similar to that of the tundra and forest tundra, due in part to their specific vegetation and proximity to several small and medium-sized lakes. Species of bird originating in the tundra, such as the willow grouse, golden plover, whimbrel, black-throated divers and greenshank, come to nest in the bogs of Belarus. Large bogs are important for birds not only during the nesting season, but also during migration. Every autumn up to 5,000 common cranes and nearly 10,000 geese arrive to rest and recuperate at the Yelnya peat bog in Belarus.
The Yelnya peat bog
Yelnya is the biggest and most famous peat bog in Belarus and is recognised under the
Ramsar Convention on Wetlands of International Importance. Yelnya is situated in the Vitebsk region and occupies a
total area of nearly 20,000 hectares. The total area of the Yelnya Reserve, including the surrounding swamp forest, is 25,300 hectares.
The digging of numerous ditches has significantly lowered the groundwater level and is one of the main reasons for regular fires in the bog. The last fire, in 2002, destroyed about 70 percent of the bog’s surface. It was only in 1999 that work was undertaken to dam the ditches in order to raise groundwater levels and reduce the risk of fire. This work is carried out every year, as the dams require regular maintenance.
Animal species in the Yelnya Reserve include seven
species of amphibians, five species of reptiles and 31 species of
mammals (most of these live in remote areas but seek food in the
reserve). There are also many vipers living in the
bog. Of the nearly 100 species of birds recorded here, 23 are listed in
Data Book of the Republic of Belarus.
As fens receive moisture mainly from groundwater, they are richer in minerals, thus the vegetation is richer and the species composition more diverse in this type of mire than in peat bogs. Different types of sedges, willows, bluegrass and other plants that are adapted to wet conditions flourish here. The largest fen mire in Europe is Zvanets, a Ramsar site situated in the Brest region of Belarus. It covers nearly 16,000 hectares and is home to 644 plant species. There were once larger fens but these were drained during the Soviet era for peat excavation.
Fen mires are also home to unique fauna. The most famous example is the aquatic warbler, a small passerine bird that has adapted to breeding exclusively in fens. According to scientists, fen drainage has reduced the aquatic warbler population by about 90 percent over the past 100 years. Once widespread across the continent, the bird now breeds in just 50 areas in Belarus, Ukraine, Poland, Lithuania and Germany where sedge mires still exist that correspond in terms of size and the composition of vegetation. The small population of aquatic warblers — fewer than 50 birds — in Pomerania (northeastern Germany and northwestern Poland) is gradually disappearing, and the bird has not been seen in Hungary since 2007. Of the approximately 20,000 remaining birds of this species, almost half live in Belarusian mires. Numerous and expensive measures to maintain water levels and restore the damage done by draining the Belarusian mires, financed by the international community, have at least succeeded in halting the declining trend in the numbers of aquatic warblers. Since 1998, the bird has been used in the logo of the largest NGO in Belarus, APB-BirdLife Belarus.
The aquatic warbler is of interest not only because it is the rarest species of continental European passerine, but also because of its unique habits. The female warbler builds the nest alone, then incubates the eggs and raises the chicks herself. This is possible only where the birds are able to find large quantities of food such as insects, arachnids and small molluscs — conditions found only in fen or sedge mires.
Transitional bogs occupy an intermediate position between raised bogs, with their short, mossy vegetation, and fen mires, with their taller vegetation. They are typically located at the perimeters of raised bogs or on separate sites with poor, sandy soils in the middle of fens. They provide sufficient groundwater for plants that require few nutrients, but not enough to sustain the structure of vegetation characteristic of fens. For this reason, these types of bogs are also known as poor fens or sedge mires.
Any human activity that involves the use or alteration of wetlands poses a direct threat to them.
Belarus has no legislation that fully protects wetlands from drainage. Although it is illegal to drain wetlands for agricultural purposes, this ban does not apply to peat extraction.
Some initiatives currently being implemented, such as the Peat Programme, are actually aimed at the destruction of wetlands:
Other programmes focus on wetland restoration:
Unfortunately, it is far more time-consuming and difficult to restore wetlands than to drain them.
Further information on the protection of Belarusian wetlands can be found on the website of the local initiative group Bezbolot: bezbolot.net.