Uncertainty in timber assortment estimates predicted from forest inventory data

Uncertainty factors related to inventory methodologies and forest-planning simulation computings in the estimation of logging outturn assortment volumes and values were examined. The uncertainty factors investigated were (1) forest inventory errors, (2) errors in generated stem distribution, (3) effects of generated stem distribution errors on the simulation of thinnings and (iv) errors related to the prediction of stem form and simulation of bucking. Regarding inventory errors, standwise field inventory (SWFI) was compared with area-based airborne laser scanning (ALS) and aerial photography inventorying. Our research area, Evo, is located in southern Finland. In all, 31 logging sites (12 clear-cutting and 19 thinning sites) measured by logging machine in winter 2008 were used as field reference data. The results showed that the most significant source of error in the prediction of clear-cutting assortment outturns was inventory error. Errors related to stem-form prediction and simulated bucking as well as generation of stem distributions also cause uncertainty. The bias and root-mean-squared error (RMSE) of inventory errors varied between −11.4 and 21.6 m³/ha and 6.8 and 40.5 m³/ha, respectively, depending on the assortment and inventory methodology. The effect of forest inventory errors on the value of logging outturn in clear-cuttings was 29.1% (SWFI) and 24.7% (ALS). The respective RMSE values related to thinnings were 41.1 and 42%. The generation of stem distribution series using mean characteristics led to an RMSE of 1.3 to 2.7 m³/ha and a bias of −1.2 to 0.6 m³/ha in the volume of all assortments. Prediction of stem form and simulation of bucking led to a relative bias of −0.28 to 0.00 m³ in predicted sawtimber volume. Errors related to pulpwood volumes were −0.4 m³ to 0.21 m³.     

The challenge of information service development for private forest owners: The Estonia and Finland cases

This paper investigates forest ownership objectives and the need for information among Estonian and Finnish private forest owners based on two surveys. The motivation for the analysis is the fragmenting private forest ownership in Europe. The broad lines of ownership objectives are found to be similar in both countries, and can be described under the dimensions of economic objectives, intangible values, and products and activities provided by forests. In both countries, economic and intangible objectives are considered important at the same time. Thus forest owners can be described as multi-objective. The economic objectives are ranked as somewhat more important than non-economic objectives in Estonia, but not in Finland. Estonian forest owners most strongly emphasise information about legal and economic matters, including forest taxation and forest health issues, while Finnish forest owners emphasise information about wood markets and forest taxation. Differences between the two countries may be related to private ownership being relatively new in Estonia. Some generalisations may be drawn for European forest policy. Overall, private forest owners need both information about economic issues and personal advice on how to manage forests with regard to their individual and multiple objectives. Generally, personal advice may be concentrated on the complicated and most important themes, while information can mostly be provided via written or electronic channels. Particularly in countries where private forestry is new, there is a need for personal advice on legislative and economic matters. As a conclusion, it is suggested that efficient allocation of resources and development of information services require regular analysis of private forest ownership, and segmenting private forest owners according to their objectives and information needs.     

Evaluation of reforestation potential of 83 tree species planted on Imperata cylindrica dominated grassland – A case study from South Kalimantan,Indonesia

Survival and growth of 83 tree species were tested in three separate species elimination trials on Imperata cylindrica dominated grassland in South Kalimantan, Indonesia. The trial layout was randomized complete blocks design with 6–8 replications of 5-tree line plots. At the age of two years exotics, like several Acacia species (A. mangium, A. crassicarpa, A. auriculiformis, A. cincinnata, A. leptocarpa), as well as Gmelina arborea, Paraserianthes falcataria and Cassia siamea had survival rates of 90–100%, crown width of 3–6 m and mean height of 5–8 m. Among the most promising local species were Anthocephalus chinensis, Peronema canescens and Parkia roxburghii but their growth was inferior compared to exotics. Eucalypts and pines were not among the highest ranking trees and cannot be recommended for initial grassland reforestation. At the age of 7–8 years the same species were still dominating, but increasing mortality of several species was observed. Especially Acacia crassicarpa and A. cincinnata of the exotics were affected, and indigenous Anthocephalus chinensis almost perished. Since fast early growth is necessary in first rotation reforestation of grasslands, fast growing exotic species provide a reliable basis for further activities. Final performance of reforestation species has to be confirmed in stand-level experiments and pilot plantations. Intensive work on integrating local tree species in reforestation of grasslands in the long run is recommended.     

Expression of CD34 mRNA and protein in cattle

CD34 is a transmembrane glycoprotein expressed by hematopoietic progenitors and endothelial cells. It is used widely in the clinic for purification of human hematopoietic stem cells transplants, and as an endothelial marker for several species. The aim of this study was to produce an anti-bovine CD34 antibody and to characterize the expression of CD34 mRNA and protein in cattle tissues. The bovine CD34 cDNA was cloned by RT-PCR, and the expression of bovine CD34 mRNA investigated by RT-PCR and in situ hybridization. Polyclonal antibodies were raised against CD34 polypeptide fragments expressed in Escherichia coli, and affinity purified. Alternative splicing of bovine CD34 mRNA was observed. Both splice variants were readily observed in endothelium, while the variant encoding a truncated cytoplasmic domain was mostly undetectable in bone marrow mononuclear cells. A polyclonal antibody against an extracellular fragment of the CD34 polypeptide was characterized using Western blots, cytocentrifuge preparates, and paraffin sections. CD34 immunoreactivity was enriched in lineage-depleted bone marrow cells. The antibody labelled most blood vessel endothelia in fetal and adult cattle, with highest intensity in capillaries. Newly forming capillaries in granulation tissue were also stained. Lymphatic vessels and the endothelium of liver sinusoids were negative.     

Mapping of snow-damaged trees based on bitemporal airborne LiDAR data

The use of multitemporal LiDAR data in forest-monitoring applications has been so far largely unexplored. In this work, we aimed to develop and test a simple method for the detection of snow-induced canopy changes by employing bitemporal LiDAR data acquired in 2006–2010. Our study area was located in southern Finland (62°N, 24°E), where snow-induced damage occurred in 10 permanent Scots pine (Pinus sylvestris)-dominated plots in winter 2009–2010. For the detection of snow-damaged crowns, we developed a ?CHM method by contrasting bitemporal LiDAR canopy height models (CHMs) and analyzing the resulting difference image, using binary image operations to extract the damaged crowns. Furthermore, we examined the structural and spatial factors that could explain snow damage at the individual tree level. The ?CHM method developed is based on two threshold parameters, i.e., the required height difference in the contrasted CHMs and the minimum plausible area of damage. When testing the performance of ?CHM method, we found that the plot-level omission error rates were 19–75%, while the commission error rates were 0–21%. Furthermore, the relative estimation accuracy of the damaged crown projection area (DCPA) ranged from ?16.4 to 5.4%. The observed damage could be explained at tree level by stem tapering, relative tree size, and local stand density. To conclude, ?CHM method developed constitutes a potential tool for the monitoring of structural canopy changes in the dominant tree layer if dense multitemporal LiDAR data are available.     

Snowpack quality as an indicator of air pollution in Finnish Lapland and the Kola Peninsula,NW Russia

Bulk snow samples were collected from the snowpack in open areas along two sampling lines running to the west from the Cu-Ni smelters at Nikel and Monchegorsk, NW Russia, during 1991–1993. The aim of the study was to estimate the area affected by sulphur and heavy metal deposition from the smelters. Snowpack quality was used as an indicator of deposition during winter time. The total sulphur, copper and nickel concentrations in the snowpack decreased significantly (p<0.001) with=" increasing=" distance=" from=" the=" smelters=" along=" the=" sampling=" line=" running=" directly=" to=" the=" west=" from=" monchegorsk.=" the=" deposition=" pattern=" was=" similar=" each=" winter=" during=" 1991–1993.=" the=" ph=" values=" did=" not=" correlate=" with=" the=" corresponding=" sulphur=" concentrations,=" and=" there=" was=" no=" decreasing=" ph=" gradient=" in=" the=" snowpack=" on=" moving=" towards=" monchegorsk.=" the=" effects=" of=" sulphur=" emissions=" from=" monchegorsk=" on=" snowpack=" chemistry=" were=" not=" detectable=" on=" the=" finnish=" side=" of=" the=" border.=" the=" 3-year=" mean=" of=" the=" total=" sulphur=" concentration=" was=" 0.27=" mg/kg,=" and=" of=" the=" ph=" values=" 4.92,=" along=" the=" sampling=" line=" running=" to=" the=" west=" of=" monchegorsk.=" the=" total=" sulphur=" concentrations=" near=" the=" smelters=">< 20=" km)=" varied=" between=" 0.37=" and=" 0.95=" mg/kg.=" the=" effect=" of=" the=" cu-ni=" smelters=" at=" nikel=" on=" snowpack=" quality=" was=" not=" detectable=" in=" northern=" finnish=" lapland.=" the=" 3-year=" mean=" for=" total=" sulphur=" was=" 0.20=" mg/kg=" and=" for=" ph=" 4.96=" along=" the=" sampling=" line=" running=" to=" the=" west=" of=">     

Early effects of four fast-growing tree species and their planting density on ground vegetation in Imperata grasslands

Ground vegetation development was studied under young plantations of Acacia mangium, A. crassicarpa, Gmelina arborea and Paraserianthes falcataria on an Imperata grassland site in South Kalimantan, Indonesia. The study was based on two separate trials: 1) a species trial with a spacing of 3×3 m, and 2) a spacing trial with progressively decreasing planting density. Both trials were established by use of intensive site preparation, NPK-fertilization, and weeding during the first year. Two years after planting and one year after the last weeding, ground vegetation in the first trial was dominated by Imperata cylindrica grass and shrubs Chromolaena odorata and Clibadium surinamense. In the open area (control) only Imperata grass appeared. Significant differences in total ground vegetation biomass (t ha^–1) between the tree species were as follows: G. arborea (0.2) A. mangium (1.4) A. crassicarpa (4.2) < P. falcataria(9.6) open area (11.4). The early results from the spacing trial showed similar trends in the hardwood species' abilities in Imperata suppression. Highly significant linear relationships existed in regression analysis between the distance between planted trees and the ground vegetation biomass as follows: G. arborea (r²=0.75), A. mangium (r²=0.95), A. crassicarpa (r²=0.97), P. falcataria (r²=0.96). Tree species and their planting density should thus be critically considered in forest plantation establishment on Imperata grasslands, since ground vegetation development plays a decisive role in fire susceptibility, maintenance requirements and the promotion of native species in plantations.     

Finite element modeling (FEM) simulation of interactions between wood and microwaves

The aim of this study was to use finite element modeling (FEM) as a tool to analyze microwave scattering in wood and to verify the model by measurements with a microwave scanner. A medical computed tomography scanner was used to measure distribution of density and moisture content in a piece of Scots pine (Pinus sylvestris). Dielectric properties were calculated from measured values for cross sections from the piece and used in the model. Images describing the distribution of the electric field and phase shift were obtained from the FEM simulation. The model was verified by measurements with a scanner based on a microwave sensor. The results show that simulated values correspond well to measured values. Furthermore, discontinuities in the material caused scattering in both the measured and the simulated values. The greater the discontinuity in the material, the greater was the need for computational power in the simulation.