Biomass equations for birch in Finland

Abstract

Biomass equations were compiled for the above-and below-ground tree components of birch (Betula pendula Roth and Betula pubescens Ehrh.). The equations were based on 127 sample trees in 24 birch stands located on mineral soil sites. The study material consisted of 20 temporary plots and ten plots from four thinning experiments with different thinning intensities (unthinned, moderately and heavily thinned plots).The equations were estimated for the following individual tree components: stem wood, stem bark, living and dead branches, foliage, stump, and roots. In the data analysis, a multivariate procedure was applied in order to take into account the statistical dependency among the equations. Three multivariate variance component models were constructed for the above-ground biomass components, and one for the below-ground biomass components. The multivariate model (1) was mainly based on tree diameter and height, and in the multivariate models (2) and (3) additional commonly measured tree variables were used.The equations provided logical biomass predictions for a number of tree components, and were comparable with other functions used in Finland and Sweden. The applied statistical method generated equations that gave more reliable biomass estimates than the equations presented earlier. Furthermore, the structure of the multivariate models enables more flexible application of the equations, especially for research purposes.

Greenhouse gas flux measurements in a forestry-drained peatland indicate a large carbon sink

“…2). Biomasses were estimated with the functions of Repola (2008Repola ( , 2009) and Laiho and Finér (1996) for aboveground and belowground components, respectively. The tree stand consisted of a dominant Scots pine (Pinus sylvestris) stand of 835 stems ha −1 , and an understorey of pubescent birch (Betula pubescens) trees (<500 stems ha −1 ) that were mainly found on the ditch banks.…”

“…Tree stand biomass for the years 2005 and 2000 was estimated using single tree biomass models of Laiho and Finér (1996;see Tobin et al, 2007) for the pine belowground biomass and the models of Repola (2008Repola ( , 2009) for other biomass components. Repola (2008Repola ( , 2009 …”

“…Variances of the stand biomass components are then summed taking into consideration the between-component correlations reported by Repola (2008Repola ( , 2009. Considering that the variances of the stand biomasses of the same stand for the years 2000 and 2005 must be highly correlated, random variance for the biomass increment in the five years is estimated by subtracting the random variance of the biomass in 2000 from that in 2005.…”

Modeling the Productivity of Forest Plantations with the Different Spacing the Trees

“…[1,2]. Также, в литературе представлены математические модели оценки фракций и суммарной фитомассы на основе физиологических особенностей роста видов и условий мест их произрастания [3][4][5]. Однако для анализа эффективности плантационного лесоразведения и искусственного восстановления лесов после сплошных рубок, лесных пожаров и других интенсивных воздействий необходимо дополнительно учитывать комплекс лесохозяйственных мероприятий, которые способны в значительной степени регулировать интенсивность продукционного процесса [6,7].…”

Below-canopy and topsoil temperatures in young Norway spruce and Carpathian birch stands compared to gaps in the mountains

“…Many studies dealing with the birches in European conditions (e.g. El Kateb et al 2004;Portsmuth, Niinemets 2006;Repola 2008;Balcar et al 2010;Hynynen et al 2010;Špulák et al 2011;Ešnerová et al 2012Ešnerová et al , 2013Reid et al 2014) were published. Carpathian and white birch are supposed to meet the mountain-site requirements; thus these two species can help us diversify the tree species composition of new forests.…”