Biomass distribution and crown characteristics in two Alaskan Piceamariana ecosystems

Abstract

Allometric relations for tree phytomass distribution on two black spruce (Piceamariana Mill. B.S.P.) sites in interior Alaska were developed and compared with entire unit area samples. Tree component mass equations provided R2 values ranging from a low of 0.24 to a high of 0.97, with the majority of values above 0.75. Equations were developed for foliage; live and dead cones; dead branch total, dead branch bark, dead branchwood; live branch total, live branch bark, live branchwood; bole total, bole bark, bole wood; and tree total. Regression equations were developed to predict tree height, distance from crown bottom to ground, crown width, and crown length using basal diameters. R2 values for these equations ranged from 0.89 to 0.20. Foliage comprised from 37% to 17% of the total mass for the lowland stand and 50% to 17% of the total tree mass in the upland stand for trees with a diameter class ranging from 0.32 to 7.94 cm. For these same diameter classes, the total bole mass ranged from 11% to 58% and 21% to 61% of the total mass in the lowland and upland stands, respectively. Comparisons of predicted total aboveground tree biomass, measured biomass, and an average-tree-per-diameter-class procedure showed the lowland site predictions were about 6% low and the upland site predictions were approximately 3% high. Using a second, all-tree component method of prediction, results were about 3% low for lowland sites and 4% low for upland sites. A method of prediction using an average stand diameter yielded differences ranging from 31% low for the lowland site to 45% low for the upland site.

Nutrient Cycling and Productivity

“…The data presented for this area in Quebec are generally consistent with those presented for the biomass distribution in two Alaskan forests by Barney et al (1978). In comparison with these latter forest communities, the lichen woodland has higher root/shoot ratios and a higher shrub and ground-layer biomass than the other forests.…”

Quantifying fire‐wide carbon emissions in interior Alaska using field measurements and Landsat imagery

“…As in Boby et al [2010], we assumed that emissions from boles and roots were zero because of their typically low levels of consumption [Campbell et al, 2007]. Equations from interior Alaska and Canada were used for black spruce [Barney et al, 1978;Mack et al, 2008;Ung et al, 2008;Boby et al, 2010], white spruce [Yarie and Vancleve, 1983;Ung et al, 2008], and aspen [Mack et al, 2008;Ung et al, 2008]. In each case the mean value from the collection of allometric equations was used.…”

Observed versus predicted fire behavior in an Alaskan black spruce forest ecosystem: an experimental fire case study

“…Mean values for preburn stem density (trees per hectare), dbh, total height, ladder fuel height, height to live crown, and biomass were calculated for all standing trees. Foliage biomass (kg m −2 ) for an individual tree was estimated using linear regression equations developed by Barney et al (1978) and summed by plot to obtain canopy fuel loading (CFL). Mean CFL was averaged at the plot level.…”