Turvevarojen teollinen käyttö ja suopohjien hyödyntäminen Suomessa

Abstract

In Finland, one third of the land surface is covered by peatlands. Peatlands have been used as arable fields and forestry land. Less than 1 % is utilized for industrial peat production. About 75 % of the industrial used areas have been earlier ditched for some other purposes. Today 10 000 hectares of cut-away areas have been released from peat production and by 2010 around 40 000 - 45 000 hectares will be ready for re-use. The thickness of the peat layer has an effect on the development of the flora and the fauna on the cut-away fields. The chosen re-use options depends on the quality of the ground soil as well as the opinion of the landowners. Afforestation is still by far the most popular alternative. Other possibilities are agricultural use, lakes or bird sanctuaries, different cultivation options and paludification. If forestry is chosen, the peat layer left on the bottom of the bogland should be thin so to make the root penetration into the mineral soil possible. If it is done wisely afforestration gives yields comparable to those of mineral soil forests. If a lake is to be established on a cut-away area, the thick peat layers on the bottom of the lakes increase the load of suspended solids and nutrients to the waters below. The present annual new growth of the peat resources in Finland has been estimated to be at least 15.4 million tonnes CO₂. This growth can be considered to be on the level for sustainable use. The corresponding use of energy peat in Finland could be around 40 TWh per year. Because peat is extracted also for horticultural and other non-energy purposes, the consumption of energy peat should not exceed 37 TWh. Presently, the annual use of energy peat amounts to some 21-23 TWh. Today the level of the use of peat in Finland can be considered as the sustainable use. The cut-away peatlands can work as new carbon sinks when compared to The Kyoto Agreement. It is estimated that until the year 2010 the fixation of carbon in these newly created sinks on cut-away areas will be around 0.2 million tonnes CO₂, by 2050 0.8-1 million tonnes CO₂ and by 2090 around 1.4-1.8 million tonnes CO₂. Also the peatlands drained for farming are decomposing slowly and carbon dioxide is released into the atmosphere. The about 67 000 hectares of land that were earlier used as arable land can be utilized for peat production purposes. Thus the total greenhouse gas emissions in Finland would be decreased considerably. Totally 943 persons were interviewed. According to the opinions forestry, restoration and bird lakes were considered as the best re-use options for the cut-away areas. The landowners regarded forestry as the most suitable method for re-use of the cut-away areas.