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Mires
Bogs and mires and fens are ecosystems where certain part of organic matter produced by living organisms by using solar energy is not decomposed and sediments as peat and vegetation has no connection with mineral soil. The areas, where peat layer has already occurred in waterlogged slopes, but is so thin that plant roots reach mineral soil through the peat layer, are called paludified. But discontinuation of peat-formation destroys the mire as an ecosystem.
Peat formation speed depends on the speed of plant decomposition. Ferns and horsetails (Equisetum) are decomposed quickly, followed by species of sedge (Carex spp.) and cottongrass (Eriophorum); decomposition is the slowest in case of Sphagnum and small shrubs such as heather (Calluna vulgaris), kinnikinnick (Arctostaphylos uva-ursi) and marsh rosemary (Ledum palustre).
Mires are generally formed as a result of paludification process. Paludification is caused by water regime anomalies: the quantity of rainwater exceeds the quantity of water vaporised or drained, and therefore the soil is waterlogged and lays foundation to proliferation of mire vegetation, which in turn holds water even better.
Due to excess humidity in mires it is suitable for those plants that like moist soil. The growth of mire vegetation is hindered by low mobility of water and lack of air.
Due to favourable conditions for development of mires in Estonia, we have great diversity of mires. Mires cover ca 1/5 of continental territory of Estonia, and 40% of that fifth is under bogs. According to their stage of development mires can be divided into fens and transition mires and bogs.
Ramsar Convention
The three stages of mires evolution
Website of Estonian mires
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