Determination of the foliage biomass and vertical distribution in pure pine stands
1997
Anniste, J. (Estonian Agricultural Univ., Tartu (Estonia). Faculty of Forestry)
The aim of the investigation was to get direct estimation of needle mass in some pure pine stands and also derive regression functions to estimate that by indirect method. Research was carried out in seven middle age Scotch pine stands. The sample plot was established in each stand where twelve sample trees were destructively sampled. The needle masses of sample trees, number of trees and their distribution into diameter classes were used to calculate the sample plot foliage biomass in direct way. The needle mass of sample plot (or of one hectare) was calculated also by indirect ways with nine different methods which all provided quite poor results. The best estimate (plus minus 13 per cent) was provided by function with stand stocking density and age, but it needs future investigations, because the scope of this work was limited (7 plots). The vertical distribution of needle mass in pine crown was characterised by a twoparameter cumulative Weilbull distribution function. There were found some differences in distribution between the sample plots which were explained with differences in stand stocking density and age
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