Puistu produktiivsuse rnodelleerimisest.
1993
Jogiste K.
The productivity of tree stand is a phenomenon that has been treated within the frameworks of serveral disciplines. The aim of the present paper is to provide an ecological interpretation of the productivity concepts used in forestry. The production concept is applied to several quantities to measure and characterize the productivity. The trees produce more than we can see as accumulated biomass in tissues. Arising from that the distinction between net primary production and gross primary production is made. Additional losses of accumulated biomass from the tree stand occur due to the shedding and mortality. The change in the stand biomass is expressed in equation (2) where K is growth and S is the loss of biomass. The methods of forest mensuration do not yield strict, functional relationships in production process studies. The functional relationships can be found and used on the level of plant physiology. These relationships could be used as basis of productivity models.
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