Kasvukohatingimuste m ju raiej tmete kuivmassile

To limit the emissions of greenhouse gases the wider utilization of renewable energy is mandatory for all EU countries. The aim of the present study was to estimate the potential quantities of harvesting residues as a source of renewable fuel. The sample plots were selected to cover the majority of site types. Together with the earlier studies data was collected from 30 felling areas from 23 different site types. The data missed from bearberry alvar, blue moor grass and carr site types, which 1.1% of the forest area of Estonia. During the study randomly 3 sample plots were created in 30 felling areas, where all harvesting residues were scaled. To determine the moisture content the the samples were taken from sample plots for laboratory analysis. Based on the characteristics of the stand and the weight of the harvesting residues from different types of stand 2 formulas of linear regression were composed. As input data the characteristics of growing conditions were used and the output was oven dry weight of harvesting residues per m3 of the stem. Average volume of the stand M (m3/ha) and the site index H100 (m) did not give statistically reliable relation with the oven dry weight of harvesting residues per m3 of the stem. Reliable relation was got with the thickness of organogenic layer of soil OHOR (cm) and co-ordinates of the centre from the ordination scheme of forest site types (L hmus, 1974, 2004). As a result it was determined that depending on the forest site type the oven dry weight of harvesting residues per m3 of the stem varies from 22 m3/ha (bog whortleberry site type) to 144 m3/ha (alder fen site type). If to consider the average bulk density to be 500 kg/m3, the share of harvesting residues from the volume of the stand varies from 4.4 to 28.8%.