Articles containing the keyword 'analysis'

In the last decades, architectural analysis has been used to understand and to model plant development. These studies have led us to reconsider the problem of measuring plants while taking into account their topological structure at several scales of detail. A computational platform, called AMAPmod, was created to work on such plant representations. This paper outlines the general methodology used in AMAPmod to represent plant topological structures and to explore these special types of databases. Plant structures are first encoded in order to build corresponding formal representations. Then, a dedicated language, AML, enables the user to extract various types of information from the plant databases and provides appropriate analysing tools.

• Godin, E-mail: cg@mm.unknown
• Caraglio, E-mail: yc@mm.unknown
• Costes, E-mail: ec@mm.unknown

The existence and direction of causal relationships between the time series for the Finnish roundwood market for the period 1960–1994 is tested. Using simple bivariate analysis, we found evidence that for both logs and pulpwood, the lagged prices are helpful in forecasting quantity for the next year, but not vice versa. Saw log stumpage prices have significantly Granger-caused pulpwood prices over the business cycles, but the effect has diminished towards the present time. For quantities traded, the direction of causality was rather from pulpwood to saw logs. The consistency of bivariate test results was checked by the Granger-causality tests within trivariate VAR-models for both markets, and the results were found to be fairly similar to bivariate tests. The price fluctuations in the international markets for forest products have been found to be carried to domestic wood markets dominantly via the pulpwood part of the market.

• Toppinen, E-mail: at@mm.unknown

The horizontal and vertical stand structure of living trees was examined in a managed and in a primeval Norway spruce-dominated forest in Southern Finland. Tree size distributions (DBHs, tree height) were compared using frequency histograms. The vertical distribution of tree heights was illustrated as tree height plots and quantified as the tree height diversity (THD) using the Shannon-Weaver formula. The horizontal spatial pattern of trees was described with stem maps and quantified with Ripley's K-function. The spatial autocorrelation of tree sizes was examined with semivariogram analysis. In the managed forest the DBH and height distributions of trees were bimodal, indicating a two-layered vertical structure with a single dominant tree layer and abundant regeneration in the understory. The primeval forest had a much higher total number of trees which were rather evenly distributed in different diameter and tree height classes. The K-function summaries for trees taller than 15 m indicated that the primeval stand was close to complete random pattern. The managed stand was regular at small distances (up to 4 m). The semivariograms of tree sizes (DBH tree height) showed that the managed forest had a clear spatial dependence in tree sizes up to inter-tree distances of about 12 meters. In contrast, the primeval spruce forest had a variance peak at very short inter-tree distances (< 1 m) and only weak spatial autocorrelation at short inter-tree distances (1–5 m). Excluding the understory trees (h < 15 m) from the analysis drastically changed the spatial structure of the forest as revealed by semivariograms. ln general, the structure of the primeval forest was both horizontally and vertically more variable and heterogeneous compared to the managed forest. The applicability of the used methods in describing fine-scale forest structure i discussed.

• Kuuluvainen, E-mail: tk@mm.unknown
• Leinonen, E-mail: kl@mm.unknown
• Nygren, E-mail: mn@mm.unknown
• Penttinen, E-mail: ap@mm.unknown

A calculation procedure is presented for calculating and analysing remeasured permanent sample plots. Data for eight different fixed and variable size plot types were simulated on the basis of two stands whose trees were mapped and measured in 1982 and 1986. The accuracy and efficiency of the plot types were assessed and compared.

The calculation procedure is based on tree-wise expansion factors and the division of tree sampled into state/measurement classes. Nine classes were required for variable size plots and six for fixed size plots. A relascope plot with basal-area factor 1 (m²/ha) proved to be most efficient for estimating basal-area at a given time and a fixed size circular plot with radius 10 m for estimating basal-area increment over a given time period.

The main problems were related to the estimation of non-measurable variables, e.g., the initial diameters of ingrowth trees, i.e., trees having passed the threshold size during the measurement period. Most problematic were cut trees belonging to the ingrowth or sample enlargement classes. It is nevertheless thought that the system is appropriate for monitoring forest changes and making sensitivity analyses with permanent sample plots.

• Poso, E-mail: sp@mm.unknown
• Waite, E-mail: mw@mm.unknown

The first aim of this study was to develop a simulation model describing the flow of different timber qualities to different firms. The second aim was to study preliminary the factors which affect timber distributions. In addition, we tested the hypothesis that in a small sawmill firm the traditional way of organizing timber procurement does not direct effectively good quality logs to the special production. The game theoretic approaching and the principles of Monte-Carlo simulation were applied in development of the simulation model. The most important factors of the model were tried to find for further studies with sensitive analysis. Empirical validation brought forth promising results in the area of one municipality. The buyer’s awareness of a marked stand, the seller’s willingness to sell a marked stand, the buyer’s ability to pay for wood and the proportion of first quality pine logs in a marked stand affected the distribution of pine logs. The results also supported the hypothesis that the traditional system, in which sawmills or their own forest departments procure themselves all timber needed, is not the most effective way to direct enough good quality timber to the special production.

• Tolvanen-Sikanen, E-mail: tt@mm.unknown
• Harstela, E-mail: ph@mm.unknown
• Sikanen, E-mail: ls@mm.unknown

Tree height data from 33 progeny trials of Scots pine (Pinus sylvestris L.) were used to determine the effect of within-plot subsampling on the magnitude of statistically detectable differences between families, family heritability and correlation of family means based on different sample sizes. The results indicated that in trials established with a standard plot configuration of 25 trees per plot, measuring only 10–15 trees gives nearly the same precision as with assessment of all the plot trees. Even as few as 4–6 trees assessed per plot may constitute a sufficient sample if families or parental trees of extreme performance are being selected. Trials established with non-contiguous plots were found to be more efficient than those established using multiple-tree contiguous plots.

• Haapanen, E-mail: mh@mm.unknown

Relationships between bulk density and organic matter (OM) content, textural properties and depth are described for forested mineral soils from Central and Northern Finland. Core samples were taken of 0–5, 30–35 and 60–65 cm layers at 75 plots. Three measures of bulk density were calculated: the bulk density of the < 20 mm fraction (BD₂₀), the bulk density of the < 2 mm fraction (BD₂), and laboratory bulk density (BD_l). BD_l was determined from the mass of a fixed volume of < 2 mm soil taken in the laboratory. All three measures of bulk densities were strongly correlated with organic matter content (r ≥ -0.63). Depth and gravel (2–20 mm) content (in the case of BD₂) were also important variables. BD_l was sensitive to clay contents > 7% but did significantly improve the prediction of both BD₂ and BD₂₀ in coarse soils (clay contents ≤ 7%). Predictive models were derived for coarse soils.

• Tamminen, E-mail: pt@mm.unknown
• Starr, E-mail: ms@mm.unknown

Variation in needle nutrient concentrations with age and vertical location in the crown was studied in three Scots pine (Pinus sylvestris L.) stands growing on peat soils in Eastern Finland. The concentrations of N, P, Fe and Zn decreased down the crown and those of Ca and Mn increased. Potassium and magnesium concentration patterns differed between sites.

Potassium and Mg concentrations were highest in the current needles at all heights in the crown, iron and manganese concentrations were highest in the oldest needles. The concentrations of N, P and Zn did not vary with needle age.

• Finér, E-mail: lf@mm.unknown

An alternative approach to formulating a forestry goal programming problem is presented. First, single objective optima levels are solved. The Analytical Hierarchy Process is applied in the estimation of a priori weights of deviations from the goal target levels. The ratios of the weights can be interpreted as relative importance of the goals, respectively. The sum of the weighted deviations from all single optima levels associated with the management goals is minimized. Instead of absolute deviations, relative ones are used. A case study problem of forest management planning with several objectives, measured in different units, is analysed.

The PDF includes an abstract in Finnish.

• Kangas, E-mail: jk@mm.unknown
• Pukkala, E-mail: tp@mm.unknown

Correlation functions of the mean volume, land use class and soil class were estimated using the data of the Finnish National Forest Inventory. Estimated functions were used for approximating the standard error of e.g. the mean volume of a cluster of plots. Standard error estimates can be used for comparing different inventory designs.

The PDF includes an abstract in Finnish.

• Korhonen, E-mail: kk@mm.unknown
• Maltamo, E-mail: mm@mm.unknown

The light reflected from the crowns of Scots pine (Pinus sylvestris L.) clones was measured spectroradiometrically during and after growing season. Standard deviations of the spectra of pine clones showing differences in moose browsing intensity were compared. A new algorithm was developed for predicting the browsing intensity of moose (Alces alces).

The PDF includes an abstract in Finnish.

• Silvennoinen, E-mail: rs@mm.unknown
• Hämäläinen, E-mail: rh@mm.unknown
• Nygrén, E-mail: kn@mm.unknown
• Weissenberg, E-mail: kw@mm.unknown

The economic analysis is based on computer simulations which covered a seedling rotation and three successive coppice rotations. Calculations were carried out for the four site productivity classes in Eucalyptus globulus plantations. The rotation length that maximized the land expectation value is 12–20 years for seedling rotation and 8–16 years for coppice rotations with discounting rates 2–8%. The mean wood production is over 40 m³/ha/a in the best site class and about 10 m³/ha/a in the poorest class with rotation lengths ranging from 10 to over 20 years. Thinnings increase the wood production and land expectation value by a few percentage points. In areas suitable to Eucalyptus globulus growth, the land expectation value is considerably higher in forestry than in agriculture, except in very poor areas or with very high rate of interest.

The PDF includes an abstract in Finnish.

• Pohjonen, E-mail: vp@mm.unknown
• Pukkala, E-mail: tp@mm.unknown

The purpose was to analyse the importance of forestry and forest industry in the Finnish economic development since the 1950’s, and to find out how the sector has contributed to the growth of the national economy through other sectors. Data were derived from the input-output tables of 1959, 1970 and 1980. Information provided by Hirschmanian linkages was expanded by taking into account e.g. induced, consumption, final demand and absorption linkages. The linkages of forestry and forest industry had multiplied during the study period. Both final demand linkages and intermediate product linkages were significant. The sector’s contribution to the development of metal and machinery and equipment industries as well as that of energy/water supply was significant. Integration with most other sectors has increased. Indirect production coefficients of forestry and forest industry were larger than on average in manufacturing. Because of labour productivity growth, production and employment coefficients were different.

The PDF includes an abstract in Finnish.

• Haltia, E-mail: oh@mm.unknown
• Simula, E-mail: ms@mm.unknown

This study deals with significance of the number of needle year classes in estimating the nitrogen, phosphorus, potassium and magnesium status of Scots pine (Pinus sylvestris L.) plants on the basis of needle analysis. Due to the nutrient retranslocation deficiencies in these nutrients are best determined by analysing separately the needles of the topmost branch whorls possessing one, two or three needle year classes. The concentrations of those nutrients which are not scarce will then increase as needle year classes decrease. In cases of deficiency, on the other hand, the content of the nutrient concerned will remain the same or decrease. Only severe deficiencies are revealed by the examination of the nutrient concentrations of only the youngest or the oldest needles.

The PDF includes an abstract in English.

• Raitio, E-mail: hr@mm.unknown

The usefulness of forest sector models in forest policy analysis is discussed, mainly based on experiences from Norway. Forest sector modelling is contrasted to two alternative approaches: (i) Intuitive, verbal analysis, and (ii) econometric models. It is concluded that forest sector models, properly developed in contact with the policy makers, should be of considerable value in forest policy analysis.

• Solberg, E-mail: bs@mm.unknown

Land use problems are very often a serious obstacle to forestry development in several countries of both developed and developing world. To overcome these problems an integrated land use policy is needed for designing and implementing innovative programs aimed at the integrated development of forestry with other land uses and the social, cultural, political, ecological and economic environment involved. Policy analysis can assist in the success of such programs by identifying the people’s needs and concerns, by gathering information about land capacity, land tenure and the traditional production systems, by testing alternative polices and by evaluating the programs after their implementation so that the necessary readjustments are made.

• Papanastasis, E-mail: vp@mm.unknown

This paper considers the problems of world’s forestry and emphasizes the policy nature of the most threatening issues. A policy science approach is needed in order to be able to provide effective tools to solve the problems. Incremental forest policies followed are evaluated to be too tardy to respond to the many forestry issues of today. Managing the global forestry issues presupposes the design of new and more effective and efficient public policy programs. More profound policy analysis is therefore needed to improve the intellectual basis for planning and decision making. The advancement of the research on the effectiveness presupposes further development of the theories of timber supply and forestry investments as well as the improvement of national forestry statistics. The whole forest policy process should be a subject to intensified systematic research.

• Tikkanen, E-mail: it@mm.unknown

Gravimetrically expressed nutrient concentrations of soil analysis were converted to volumetric values using dry bulk densities measured in the natural state and in the laboratory after air-drying and sieving the samples. The aim was to examine, using volumetric samples representing different soil classes, exactly how the converted nutrient values calculated by this laboratory method describe volumetric nutrient contents in undisturbed soil. In the fine soil classes undisturbed bulk density was higher than laboratory bulk density and converted nutrient concentrations were too small. In coarser soil classes the reverse was true, and the values were too high.

The PDF includes an abstract in English.

• Niska, E-mail: kn@mm.unknown

Different sampling methods (the percentage cover scale, the graphical method, two-point quadrat methods, the five-, nine- and twelve-class cover scales, and the biomass harvesting) were used in estimating abundance of ground vegetation in clear-cut areas and on an abandoned field in Southern and Central Finland. The results are examined with the help of DCA ordinations. In addition, the species numbers and diversity indices obtained by different sampling methods are compared.

There were no large differences in DCA configurations between the sampling methods. According to all the sampling methods, a complex soil fertility-moisture gradient (a forest site type) was interpreted as the main ordination gradient in the vegetation data for clear-cut areas. However, different sampling methods did not give similar estimates of species numbers and diversity indices.

The PDF includes a summary in Finnish.

• Jukola-Sulonen, E-mail: ej@mm.unknown
• Salemaa, E-mail: ms@mm.unknown

The Lauhavuori area is barren, consisting of sandstone and granite bedrock covered by coarse moraine and sand. The woodlands are dominated by Scots pine (Pinus sylvestris L.) and Calluna. The top of the hill, rising 230 metres above the sea level, is more fertile, as it was never covered by the ancient Baltic Sea. Numerous springs and spring brooks are bordered by herb-rich Norway spruce (Picea abies (L.) H. Karst.) woodlands and swamps. Although most of the peatlands are oligotrophic, several mesotrophic peatland plants occur, some southern, giving the peatlands a rather northerly character.

The study area is 8 by 12 km. According to the vegetation analysis, 310 species were identified, 208 of which were native to the area and 102 immigrants. The native species can be separated from the immigrants because the area is largely undisturbed.

The PDF includes a summary in English.

• Suominen, E-mail: js@mm.unknown
• Varkki, E-mail: av@mm.unknown

Our preliminary findings indicate that the content of total sulphur and soluble fluorides in needles of the Scots pine (Pinus sylvestris L.) reflects the degree of air pollution with sulphur and fluorine compounds. A project for a map of air pollution in Poland, based on chemical analysis of Scots pine needles, is presented. Results of the total sulphur and soluble fluoride content in 2-year old needles from 15- to 25-year-old trees should yield a picture of air pollution with sulphur and fluorine compounds. The first stage will involve the preparation of a map of the area between the Warsaw and Plock agglomerations. This area will be divided into 10 squares with side dimension of 25 km each. Samples will be taken at 5 different sites in each square and also approximately every 5 km along a straight line between these towns.

• Molski, E-mail: bm@mm.unknown
• Bytnerowicz, E-mail: ab@mm.unknown
• Dmuchowski, E-mail: wd@mm.unknown

The need for the planning and analysing of public policy has increased in economic and social policy, along with the expansion of the public sector, i.e. as the number of aims of the policy has increased and the objects of it have become more versatile, the objects of allocation have likewise been multiplied. In addition, the significance of planning a public forest policy has been emphasized by many economic and social changes in forestry and the timber economy.

The purpose of the present paper is to outline a general frame of reference for empirical policy analysis, upon which the effectiveness analysis of forest policy is also based. The approach serves as a methodological frame for the empirical analysis, presented in the following paper of this issue of Silva Fennica, in which econometric methods are applied to the examination of the effect of public forest policy.

• Tikkanen, E-mail: it@mm.unknown

Ashed tree samples from sound and decayed Norway spruce (Picea abies (L.) H. Karst.) were studied by means of fast neutron activation analysis, and for comparison, also by X-ray fluorescence analysis. In fast neutron activation analysis, the following elements were detected: (Na), Mg, Al, Si, K, Ca, Mn, Rb, Sr and Ba, and according to the results of the X-ray fluorescence method the elements present in the wood samples were: K, Ca, Mn, Rb, Sr and Ba. A general diminishing was revealed by both methods in most elemental concentrations studied, with exception of K and Rb, when going from a sound tree to a decayed one. The use of the ratio of the amounts of potassium to calcium as an indication of the degree of decay is therefore proposed.

The PDF includes a summary in Finnish.

• Raunemaa, E-mail: tr@mm.unknown
• Hautojärvi, E-mail: ah@mm.unknown
• Jartti, E-mail: pj@mm.unknown
• Laurén, E-mail: jl@mm.unknown
• Lindfors, E-mail: vl@mm.unknown
• Räisänen, E-mail: jr@mm.unknown

An electron probe X-ray microanalyser was used to study the occurrence of phosphorus, sulphur and calcium in the bud apices of dormant Scots pine (Pinus sylvestris L.). The material was collected during the winter months (November–February), fixed in Carnoy’s fluid, dehydrated, and mounted in paraffin wax. Of the 10 μm longitudinal section, the ones containing the middle portion of the apices were glued to the specimen supports and vacuum coated with aluminium. Three parallel line analysis were run over the corpus and the uppermost portion of the pith. Results obtained so far suggest that no marked changes occur in the position and level of the three elements during the study period.

The PDF includes a summary in English.

• Kupila-Ahvenniemi, E-mail: sk@mm.unknown
• Hankonen, E-mail: sh@mm.unknown
• Sivonen, E-mail: ss@mm.unknown

Among the users of factor analysis there seems to be a tendency to extend the use of this method to tasks where it suits poorly. It is therefore important to emphasise at least the following aspects: 1) More critical attention should be paid to problems of interpretation especially at situations where method is aimed at analysing the causal relationships among the variables; 2) The study problem should be stated so clearly as to make it plausible to evaluate the suitability of factor model to the problem.

The PDF includes a summary in English.

• Järveläinen, E-mail: vj@mm.unknown

A hypothetic problem is outlined as an example of the type of problem to which factor analysis should not be applied. Apart from this, attention is paid to industrialisation, a concept characterised by several variables, none of which can be held constant while analysing its influence on attitudes by multi-variable cross-tabulation techniques.

The PDF includes a summary in English.

• Riihinen, E-mail: pr@mm.unknown

Some alternative ways of using factor analysis in the field of forest owners’ behaviour are explored in the article, in the light of two new Finnish publications. The philosophical and mathematical propertied of factor analysis are often considered too restrictive, and thus its applicability to different fields too limited. A good knowledge of the method and the subject matter theories seems to be an important prerequisite for a successful application of factor analysis. Otherwise the researcher is too dependent on the general recommendations concerning the use of factor analysis and cannot fit its use in his special situation and the whole methodological setting of the study.

The PDF includes a summary in English.

• Hahtola, E-mail: kh@mm.unknown

The Sinivuori Nature Park, located in the northeast part of the county of Häme in Southern Finland represents the rare fertile forest lands in the country, and belong partly to the so-called centre of herb‐rich forests of Häme. Sinivuori is one of the smallest nature reserves in Finland (64 ha). The detailed vegetation analysis was performed in 1969, supplemented by earlier and later observations. The area was divided into 69 one-hectare squares for the study of the flora and vegetation.

The most common rock in the park is mica schist. The pH of the soil is relatively high, in average 6.6. Thermal-time sum is 1,100–1,200. The vegetation differs to a large extent from the surrounding areas. 169 vascular plants were found in the area, some of which very rare in the area. The paper lists the plants and their abundance in the area, and the vegetation is described by the forest types. Distribution maps are presented for the species.

The PDF includes a summary in German.

• Rutanen, E-mail: kr@mm.unknown

A vegetation analysis was performed in Muhkuri experimental area of the Forest Research Institute. The area is located in southwest Finland near city of Turku. The dominant tree species of the area is oak (Quercus robur L.) which can be found in all the area. Common woody species are also aspen (Populus tremula L.), mountain ash (Sorbus aucuparia L.), hazel (Corylus avellana L.), juniper (Juniperus communis L.) and mountain currant (Ribes alpinum L.). A total of 198 vascular plants were found in the area, 34 of which were common in most parts of the area. Typical vegetation of different parts of the area is described. Finally, a list of all plant species is presented in the article.

The PDF includes a summary in German.

• Auer, E-mail: aa@mm.unknown

Vegetation inventory was made to study plant species growing in herb-rich forest in northern Pirkkala-Tyrvää area in Southern Finland. The area belongs to a district that is rich in grass-herb forests, where the bedrock is calciferous. Six herb-rich forest site types were identified in the area. The species composition in the herb-rich forests was compared to those in Turku in southwest Finland, and in Ladogda Karelia in Eastern Finland.  The main characteristics of the plant associations were similar, but there were a few species that are common in Pirkkala-Tyrvää area that are rare in the other areas, and vice versa. The district rich in grass-herb forests of Pirkkala may extend more westwards than it has been assessed earlier. Finally, the article lists the plant species found in the herb-rich forests in the area and defines their distribution and abundance.

The PDF includes a summary in German.

• Mäkelä, E-mail: tm@mm.unknown

Typical for the area of Längälmävesi, in Satakunta in Southern Finland, are densely populated fertile lowland areas near the waterways and poorer sparcely populated upland areas. The changes in fertility of the land influence the vegetation, and has directed where the population has settled. A vegetation survey was made using specific plant species as indication to fertility. A detailed description of the species composition and distribution of the plant species indicative for fertile land is presented in the article.

Analyzing the fertility only based on the plant species indicative for rich soils underestimates the proportion of fertile lands. Farmlands, on the other hand, have been cleared also on less fertile soils, which would give an overestimate of the fertile lands. A map of fertile lands was drawn based on both vegetation and location of the fields. The changes in fertility influenced also bird species observed in the area.

The PDF includes a summary in German.

• Cajander, E-mail: oc@mm.unknown

The purpose of this study is to clarify the forest types in pure coniferous stands in Åland in Finland, to study them in a biological light and account for the production of the stands on respective sites. The flora of the forest types in Åland has been described in an earlier study, but as the plant associations have not been described it has often been difficult to determine the correct types in field work. Sample plots were chosen in coniferous forests with maximum 20% of other species. The vegetation analysis was limited to determine composition of species, projected coverage and the frequency of species. In addition, cubic volume and growth of the growing stock was calculated for the stands.

The results of the study showed that site type and fertility correspond to each other nearly without exception only on normal moraines, if only the ground vegetation is used as a criterion for the type. The general occurense of soils of different qualities makes it necessary to determine, besides forest type, other characteristics in the stands, preferably the dominant height. The total production of coniferous forests with great probability is smaller in Åland than in mainland Finland. The results can be applied also to Åboland’s archipelago, where the milieu of the coniferous forests is similar.

The PDF includes a summary in English.

• Högnäs, E-mail: bh@mm.unknown

Quantitative investigation of bacteria in the humus is needed when the intensity of their function in decomposition in the soil is studied. In this study bacterial density of humus was measured using dilution plate method, which was subjected to thorough investigation. The method was chosen, despite its complexity, because it is quite consistent, each stage can be studied separately and the reliability can be tested. The aim of the study was to determine the best way to take samples so that the sample will represent the bacterial population as closely as possible, and to optimize homogenization and dilution of the sample and the assays.

On the basis of the results of the investigation, a procedure was developed for quantitative determination of aerobic bacteria in the humus by the dilution plate method. The paper recommends that subsamples are collected systematically from at least 25 different points. The moisture and temperature of the samples should remain similar to the natural environment until preparation of the dilution. The sample was homogenized with the Bühler homogenizer, which is constructed so that a certain degree of asepsis can be maintained and the speed of the apparatus can be regulated. The content of the mineral nutrients of the sample must be determined when choosing the way of homogenization to obtain the highest number of colonies per plate. The sample was diluted with either 0.1–0.01% peptone solution or 0.5% soil extract. The most advantageous degree of dilution was obtained by testing with the aid of Fisher’s dispersion index the probability of the Poisson distribution in the results.

• Schalin, E-mail: is@mm.unknown

The objective of this study has been to discover some of the basic principles on which an increment for a large forest area might be forecast. Because the stands in a large forest area vary considerably in density and are subject to different kinds of treatment, the main interest falls on the stand characteristics which determine the increment percentage in such forest conditions as these. The material used in the study has been published earlier, it consisted of sample plots of Scots pine (Pinus sylvestris L.) stands (Nyyssönen 1954).

Increment functions are of great importance in the increment forecast for cutting budget. Because 60-80% of the variation in the increment percentage can be explained by stand characteristics in circumstances where the age of the stand is 40-130 years and the volume vary with a coefficient of variation 0.6-0.7, regression equations for increment percentage may be based on a number of sample plots smaller than in a growing stock inventory in the same conditions. It is possible to get accurate results with relatively small number of sample plots. Furthermore, the smaller amount of increment sample plots makes it possible to develop measurement techniques.

The increment functions enable study of increment as a biological process. However, conclusions about biological process on the basis of regression equations should be made with caution. Still, regression analysis is a powerful tool in yield studies.

The PDF includes a summary in Finnish.

• Kuusela, E-mail: kk@mm.unknown
• Kilkki, E-mail: pk@mm.unknown

Especially in experimantal ecological research it is used small sample plots that are inventoried consequently. The paper describes a method for establishing small sample plots, developed by the writer in 1956. In the method, the central point of the sample plot is marked with an iron skewer, and the marking of the area to be inventoried was accomplished with a circular frame that is movable. The frame was fitted to the skewer with an aperture that indicated the central point. The area of the frame was relatively small, 0,25 m². The sample plots were arbitarily placed at intervals from one another.

The PDF includes a summary in Finnish.

• Yli-Vakkuri, E-mail: py@mm.unknown

The analysis of costs is the foundation for the efficient management of logging activities. However, there is little research on cost accounting of logging. This article is an overview on harvesting of timber and its cost accounting, concentrating on joint costs. Costs have to be divided on their structural elements and then regrouped according to different accounting needs to be investigated. This investigation bases the structural cost analysis on running booking of costs. Due to the variability of logging, the costs are divided in detail into categories. The costs of logging are classified by their origin into personnel cost, material costs, costs of services, compensation for use, unrequited costs, risks, depreciation and interest. Further, the costs are classified according to the subject and quality of performance, and by location.

The PDF includes a summary in English.

• Einola, E-mail: je@mm.unknown

The paper is a dissertation paper that describes analysis of pH in diluted bicarbonate solutions using different partial pressures of CO₂. In the work, an equation was obtained from the balance equations of a base-bicarbonate-water system. Similarly, an equation was obtained to describe the relationship of partial pressure of CO₂ and hydrogen ion concentration of a bicarbonate solution. This equation can be used to determine the bicarbonate concentration of a gas mixture.

The PDF includes a Finnish and German summary.

• Carlberg, E-mail: jc@mm.unknown

The paper presents preliminary results of paleobotanical studies on vegetation in Åland, south-west Finland. The investigations concentrated on studying arrival of tree species and stratigraphy of peatlands. According to the studies, some plant fossils found in the peat (Ceratophyllum submersum, Sparagnium neglectum, Najas flexilis) indicate that climate of the region has earlier been warmer than at the present. The present forests in Åland are dominated by coniferous species, but the pollen analysis of the peat indicate that Norway spruce (Picea abies (L.) H. Karst.) became a common species in the region about by the time of Christ’s birth. The species has reached its present distribution in Åland relatively late. The pollen analyses give relatively little information about the arrival of birch (Betula sp.) and Scots pine (Pinus sylvestris L.), but it seems obvious that occurrence of birch reached its culmination just before spruce. During the warm period common alder (Alnus glutinosa (L.) Gaertn.) was the most important species, and also pollen of oak (Quercus robur L.), kinden (Tilia cordata L.) and elm (Ulmus sp.) was relatively common in the peat of some of the studied peatlands. An interesting finding was the pollen of Carpinus betulus in many sites in Åland.

The PDF includes a Finnish and German summary.

• Backman, E-mail: ab@mm.unknown

Pollen analysis has given information on development of the tree species composition after the ice age, but this kind of studies have not been published in Finland. In this study, pollen analysis was performed in five peatlands in the southwest Finland. According to the analysis, the forests of the area have had similar tree species composition for many thousands of years. Scots pine (Pinus sylvestris L.) has been the dominant species as long as there has been Norway spruce (Picea abies (L.) H. Karst.) in the area. Norway spruce seems to have arrived about 4,500 years ago. It increased slowly in the beginning, and after reaching a maximum has been slowly decreasing. Before spruce arrived, Betula sp. was more abundant, and seemed to be the dominant tree species in some places. Traces of fire in the peat layers indicate that forest fires have been common before people arrived in the area, and may have beneficial to birch. Like Betula sp., also Alnus sp. were more common before spruce arrived. Also pollen of other broadleaved species, for example, Tilia sp., Ulmus sp. and Corylus could be found. However, Quercus pollen was not found. The paludification of the peatlands had begun at different times which indicates that there has not been a common cause for the development of the peatlands in the area.

The PDF includes a summary in German.

• Lukkala, E-mail: ol@mm.unknown

The article analyses the efficiency of forest work, and the use of time and motion study methods in forest work. Forest work can be characterized by little use of machinery. It cannot be repeated as orderly as industrial work. This affects also how the efficiency of the work can be measured. Only parts of the work can be timed. The study takes making of piled wood as an example. First are determined the standard times for the work moments. They include the time used to prepare the piled wood, and the waste time. It is concluded that forest work can be standardized with the methods of work analysis.

The PDF includes a summary in English.

• Lassila, E-mail: il@mm.unknown

The article summarizes the observations about forest types from different parts of Estonia. The chosen examples represent the normal forest where age class division is natural and the species composition has not been altered through felling or grazing. These are mainly found in the areas of earlier manors of the nobility. The samples are only from mineral soils. Vegetation analysis and middle-European height-over-age-survey were made.

Because of the great share of herb-rich-forest the forest type classification for Estonia is complex. There are many types that have not been described earlier.

The study describes the characteristics and the vegetation types of the heath forests, fresh forests, half-herb-rich-forests and herb-rich-forests.        

The volume 34 of Acta Forestalia Fennica is a jubileum publication of professor Aimo Kaarlo Cajander.

• Linkola, E-mail: kl@mm.unknown

The article tries to develop the method for defining the requirements of fertilizers for soil. The chemical soil analysis is also seen as the requirement for exact site classification based on height over age. The study is based on 1500 soil samples, one half of them from forest soils, the other half from arable land soils.    

The productivity of different forest types and the results of soil analyses are in line with each other. The most important growth factors are discerned.  Some shortcomings of the method are discussed.  Combining the soil analysis and the plant analyses of the sample plots seems to give the most accurate about the amount of nutrients that are available for the plants.

• Valmari, E-mail: jv@mm.unknown

The forest site classification system used in Finland is based on ground vegetation rather than the wood production capacity. A. K. Cajander has presented a detailed classification of different forest site classes in different parts of the country. This study focuses on the forest site types of Northern Finland, which are less well defined. The article presents detailed vegetation analysis and lists of plant species in different forest site types in Northern Finland. In contrast to southern parts of Finland, both the natural Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst) stands are uneven-aged in the north. The forests are also relatively thin. There is a marked difference in height of trees between the richest and poorest sites, but the dominant trees of the same site type were of similar height both in the north and south part of the study area. The differences in the height of dominant trees seem to be smaller than in Southern Finland. Also, in windy areas prone to snow damage, climate conditions can affect tree growth more than the forest site type. In more sheltered areas forest site type determines forest growth.

The PDF includes a summary in German.

• Lakari, E-mail: ol@mm.unknown

The paper examines the needs, premises and criteria for effective public participation in tactical forest planning. A method for participatory forest planning utilizing the techniques of preference analysis, professional expertise and heuristic optimization is introduced. The techniques do not cover the whole process of participatory planning, but are applied as a tool constituting the numerical core for decision support. The complexity of multi-resource management is addressed by hierarchical decision analysis which assesses the public values, preferences and decision criteria toward the planning situation. An optimal management plan is sought using heuristic optimization. The plan can further be improved through mutual negotiations, if necessary. The use of the approach is demonstrated with an illustrative example. Its merits and challenges for participatory forest planning and decision making are discussed and a model for applying it in general forest planning context is depicted. By using the approach, valuable information can be obtained about public preferences and the effects of taking them into consideration on the choice of the combination of standwise treatment proposals for a forest area. Participatory forest planning calculations, carried out by the approach presented in the paper, can be utilized in conflict management and in developing compromises between competing interests.

• Kangas, E-mail: jk@mm.unknown
• Loikkanen, E-mail: tl@mm.unknown
• Pukkala, E-mail: tp@mm.unknown
• Pykäläinen, E-mail: jp@mm.unknown

The profitability of fast-growing trees (Eucalyptus camaldulensis Dehnh., Acacia mangium Willd. and Melia azedarach L.) was investigated in the north-eastern and eastern provinces of Thailand. The financial, economic, and tentative environmental-economic profitability was determined separately for three fast-growing plantation tree species and for three categories of plantation managers: the private industry, the state (the Royal Forest Department) and the farmers. Fast-growing tree crops were also compared with teak (Tectona grandis L. f.), a traditional medium or long rotation species, and Para rubber (Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg.) which presently is the most common cultivated tree in Thailand.

The optimal rotation for Eucalyptus camaldulensis pulpwood production was eight years. This was the most profitable species in pulpwood production. In sawlog production Acacia mangium and Melia azedarach showed a better financial profitability. Para rubber was more profitable and teak less profitable than the three fast-growing species. The economic profitability was higher than the financial one, and the tentative environmental-economic profitability was slightly higher than the economic profitability.

The profitability of tree growing is sensitive to plantation yields and labour cost changes and especially to wood prices. Management options which aim at pulpwood production are more sensitive to input or output changes than those options which include sawlog production. There is an urgent need to improve the growth and yield data and to study the environmental impacts of tree plantations for all species and plantation types.

The PDF includes a summary in Finnish.

• Niskanen, E-mail: an@mm.unknown
• Luukkanen, E-mail: ol@mm.unknown
• Saastamoinen, E-mail: os@mm.unknown
• Bhumibhamon, E-mail: sb@mm.unknown

The effects and relative efficiency of alternative forest taxes are analysed theoretically. The Fisherian two-period model of consumption, savings and timber harvesting is extended by incorporating the management intensity decision and deriving the concept of long-run timber supply. The effects of lump-sum (site productivity), realized income (yield) and ad valorem property taxes on short-run timber supply, management intensity, and long-run timber supply are established. As the core of the study, the alternative taxes are compared in order to determine the appropriate forest tax regime in terms of production efficiency. The efficiency criterion generally requires that the excess burden of taxation at any given tax revenue should be kept to a minimum. The study distinguishes between an initially undistorted economy and an economy with pre-existing distortions due to capital income taxation (interest charge deductions). When the effects on forest management decisions of forest and capital income taxes are considered as a whole, a neutral forest taxation is no longer efficient. The non-timber benefits of a forest are incorporated to examine the robustness of the tax results with respect to the objective function. Finally, forest tax issues specific to Finland are considered, and administrational and equity aspects are discussed.

The PDF includes a summary in Finnish.

• Ovaskainen, E-mail: vo@mm.unknown

Two operative forest site class estimation methods utilizing satellite images have been developed for forest income taxation purposes. For this, two pixelwise classification methods and two post-processing methods for estimating forest site fertility are compared using different input data. The pixelwise methods are discriminant analysis, based on generalized squared distances, and logistic regression analysis. The results of pixelwise classifications are improved either with mode filtering within forest stands or assuming a Markov random field type dependence between pixels. The stand delineation is obtained by using ordinary segmentation techniques. Optionally, known stand boundaries given by the interpreter can be applied. The spectral values of images are corrected using a digital elevation model of the terrain. Some textural features are preliminary tested in classification. All methods are justified by using independent test data.

A test of the practical methods was carried out and a cost-benefit analysis computed. The estimated cost saving in site quality classification varies from 14% to 35% depending on the distribution of the site classes of the area. This means a saving of about 2.0–4.5 million FMK per year in site fertility classification for income taxation purposes. The cost savings would rise even to 60% if that version of the method were chosen where field checking is totally omitted. The classification accuracy at the forest holding level would still be similar to that of traditional method.

The PDF includes a summary in Finnish.

• Tomppo, E-mail: et@mm.unknown

The basic objective in planning a forest road network is to minimize the total cost of terrain transportation, road transportation, road construction and maintenance by controlling the road location, road network density and road quality, besides environmental and ecological considerations. Studies on the optimization of forest road network have encountered difficulties in taking into account the spatial diversity of forest terrain and stands. The spatial data handling-network routing system developed in this study proves to be useful in assisting forest managers to carry out the planning of forest road networks by covering the spatial and economic analysis.

The PDF includes a summary in Finnish.

• Tan, E-mail: jt@mm.unknown

The influence of log properties (diameter, length, taper, volume, density and quality), sawing pattern, yield, sawing efficacy, stoppages, consumption of electric power and thereby on the financial result of sawing was examined. In addition, the significance of various revenues and costs were studied from the point of view of the financial result of sawing. The revenues from sawing are composed of revenues obtained from sawn goods, chips, sawdust and bark. The costs in sawing are made of raw material, capital, labour, energy and other costs. The results were calculated per diameter class and applying the basic principle of targeting all returns and costs on the different diameter classes.

The results are based on test sawings of a total of 1,606 Scots pine logs representing eight diameter classes,  using conventional frame saw sawing patterns. In addition, a sawing simulator was used. Log top diameter had a significant influence on the financial result obtained when calculations were made per log volume. The financial result obtained for the biggest diameter class exceeded that of the smallest diameter class by FIM 99.1/m³. Sawing revenues accounted for FIM 66.0/m³ and sawing costs for FIM 33.1/m³ of this difference. In addition to being influenced by the top diameter, the yield and sawing efficacy were observed to have a clear influence on the financial result. The influence of stoppages was smaller.

The only means of gaining significant improvement in the annual result obtained from sawing were improvements in the revenues from sawn goods or reductions in the cost of raw material. Increase of the minimum diameter led to a significant improvement in the annual result obtainable from sawing only if the production time remained unchanged; i.e., when correspondingly more logs from the other diameter classes were sawn. If the production time was reduced by an amount corresponding to the increase in minimum diameter, then the annual result fell dramatically except in the case of minimum diameter.

The PDF includes a summary in English.

• Hakala, E-mail: hh@mm.unknown

Genetic variation in the physiological characteristics and biomass accumulation of Acacia mangium Willd. was studied in both field and laboratory conditions. Variation in the growth characteristics, foliar nutrient concentration, phyllode anatomy and stomatal frequency was analysed in 16 different origins under field conditions in Central Thailand. Family variation and heritability of growth and flowering frequency were calculated using 20 open-pollinated families at the age of 28 months. The effect of environmental factors on diameter growth in different provenances is also discussed.

Under laboratory conditions, such physiological characteristics as transpiration rate, leaf conductance and leaf water potential were measured at varying soil moisture conditions. The responses of photosynthesis, photorespiration and dark respiration as well as the CO₂ compensation point to temperature and irradiance were also investigated. All physiological characteristics indicated differences among provenances. An attempt was made to relate the results obtained in the laboratory to the growth performance in the field. Recommendations on provenance selection for the planting of A. mangium in Thailand are also given.

The PDF includes a summary in Finnish.

• Atipanumpai, E-mail: la@mm.unknown

Multivariate methods are used to classify pine mires on the basis of edaphic properties into fertility groups in order to estimate the effect of fertilization in relation to site fertility. The data is based on two field inventories of NPK fertilization experiment in which 2,624 sample trees on 164 sample plots from 19 experimental fields were measured on Scots pine (Pinus sylvestris L.) dominated stands. The edaphic properties (total contents of nutrients and related properties) are based on 1,350 volumetric sub-samples of fertilized and non-fertilized control plots.

In a DECORANA ordination, based on standardised volumetric soil variables N-P and acid-base gradients jointly describing trophic status were distinguished. Mainly on the basis of these two gradients a TWINSPAN analysis divided the material into five edaphic groups. To independently allocate sample plots into fertility groups, discriminating multiple regressions were formed using the TS edaphic groups as class variable.

The effect of N, P, K, NP, NK, PK, and NPK treatments on tree growth was estimated on the basis of change in relative basal area increment during two growth periods. During five-year period immediately after fertilization N and P treatments evoked the strongest increase in growth. On the nutrient poor sites, the effect was almost double that on the fertile sites. The effect of N was short lasting while the P treatment still affected growth after 5–11 years. Although K treatment had little influence on tree growth needle samples collected 11 years after fertilization indicated increased K uptake on fertilized plots.

Generally, the effect of fertilization on absolute stand volume growth was small. During the 11-year study period the total increase in growth gained with NPK was some 3–4 m³/ha. Despite strong relative response of individual sample trees, due to low stand volume fertilization (and drainage) had practically no effect on volume growth on the sites of lowest fertility.

The PDF includes a summary in Finnish.

• Westman, E-mail: cw@mm.unknown

The data used to control the developed methods are presented in chapter two. The third chapter presents the statistical analysis conducted. The factor analysis shows that tree stand characteristics must be divided into three factors to able the information needed for site indexing to distinguish different site classes. The phases of model development are presented and the results of calculations with control data are shown.   

The results indicate that for calculations of nature-normal forests the suitable amount of tree stand characters for creating the site indexing function, is three.  These are: number of trees (N), basal area of the stand (G) and mean height (H).

The PDF contains a summary in Finnish. 

• Kangas, E-mail: yk@mm.unknown

With developing possibilities to analyse data automatically there is a need to develop the mathematical and statistical practices for calculations. The article presents the basis about the growth of trees and the existing models of growth, the basics on growth functions,   and the construction of a regression model to analysis the growth. The theoretical model development has been tested with three existing data sets.

The analysis of growth should be considered with dynamic models. The model need to take into account various aspects and growth factors. The model should have practical implications.

The PDF contains a summary in German. 

• Kangas, E-mail: yk@mm.unknown

• Wutzler, Max Planck Institute for Biogeochemistry, Jena, Germany E-mail: tm@nn.de
• Mund, Max Planck Institute for Biogeochemistry, Jena, Germany E-mail: mm@nn.de

The EU’s influence on national forest policies is growing, and the implementation of forest-related policies proposed by the Commission will affect the practice of forestry in Europe. For instance, the Nature Restoration Law sets concrete areal goals for restoring forest ecosystems and for conservation, the Deforestation Regulation requires meticulous tracking of wood’s origin, and the renewed Renewable Energy Directive (RED III) sets new criteria to sustainable forest biomass procurement. So far there have been no studies that have looked into the impacts from the economic and operational point of view. In this study, structural systems analysis was first performed to discover the relevant variables (and their functioning) associated with the roundwood harvesting operations and the operating environment. A scenario approach was then applied to capture the potential levels of implementation of the EU’s forest-related policies. Finally, using different scenarios (low-, moderate- and high-impact) and a systems analysis framework, the impact of alternative levels of implementation was quantified in terms of harvesting costs, measured in € m^–3. The results indicate that with the low- and moderate-impact scenarios the harvesting costs would increase by less than 10% from the current levels in three different regions in Finland. Such an increase (less than 10%) could be tolerated over a period of a few years, but a sudden increase is likely to lead to challenges to the running of businesses. With the high-impact scenario the harvesting costs would increase by between 15% and 18%, depending on the region. This magnitude of increase (of approximately a sixth) corresponds to a severe change in the roundwood harvesting operations and operating environment.

• Ahtikoski, Natural Resources Institute Finland (Luke), Tekniikankatu 1, FI-33720 Tampere, Finland https://orcid.org/0000-0003-1658-3813 E-mail: anssi.ahtikoski@luke.fi
• Väätäinen, Natural Resources Institute Finland (Luke), Yliopistonkatu 6, FI-80100 Joensuu, Finland https://orcid.org/0000-0002-6886-0432 E-mail: kari.vaatainen@luke.fi
• Anttila, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland https://orcid.org/0000-0002-6131-392X E-mail: perttu.anttila@luke.fi
• Laitila, Natural Resources Institute Finland (Luke), Yliopistonkatu 6, FI-80100 Joensuu, Finland E-mail: juha.laitila@luke.fi
• Mutanen, Natural Resources Institute Finland (Luke), Yliopistonkatu 6, FI-80100 Joensuu, Finland https://orcid.org/0000-0003-0533-9356 E-mail: antti.mutanen@luke.fi
• Lindblad, Natural Resources Institute Finland (Luke), Yliopistonkatu 6, FI-80100 Joensuu, Finland https://orcid.org/0009-0003-6766-6587 E-mail: jari.lindblad@luke.fi
• Sikanen, Natural Resources Institute Finland (Luke), Yliopistonkatu 6, FI-80100 Joensuu, Finland E-mail: lauri.sikanen@luke.fi
• Routa, Natural Resources Institute Finland (Luke), Yliopistonkatu 6, FI-80100 Joensuu, Finland https://orcid.org/0000-0001-7225-1798 E-mail: johanna.routa@luke.fi

• Semberg, Skogforsk (The Forestry Research Institute of Sweden), Uppsala Science Park, 751 83 Uppsala, Sweden E-mail: tobias.semberg@skogforsk.se
• Nilsson, Skogforsk (The Forestry Research Institute of Sweden), Uppsala Science Park, 751 83 Uppsala, Sweden E-mail: anders.nilsson@skogforsk.se
• Björheden, Skogforsk (The Forestry Research Institute of Sweden), Uppsala Science Park, 751 83 Uppsala, Sweden https://orcid.org/0000-0002-4158-102X E-mail: rolf.bjorheden@skogforsk.se
• Hansson, Skogforsk (The Forestry Research Institute of Sweden), Uppsala Science Park, 751 83 Uppsala, Sweden https://orcid.org/0000-0002-9788-1734 E-mail: linnea.hansson@skogforsk.se

• Vauhkonen, University of Eastern Finland, School of Forest Sciences, Yliopistokatu 7, FI-80101 Joensuu, Finland; University of Helsinki, Department of Forest Sciences, Latokartanonkaari 7, FI-00014 Helsingin yliopisto, Finland E-mail: jari.vauhkonen@uef.fi
• Matala, Natural Resources Institute Finland (Luke), Natural resources, Yliopistokatu 6 B, FI-80100 Joensuu, Finland E-mail: juho.matala@luke.fi
• Nikula, Natural Resources Institute Finland (Luke), Natural resources, Ounasjoentie 6, FI-96200 Rovaniemi, Finland https://orcid.org/0000-0001-8372-8440 E-mail: ari.nikula@luke.fi

Technological development gives forest companies opportunities to maintain competitiveness in the highly cost-sensitive market for forest products. However, no previous studies have examined the technological development decisions made by forest companies or the support tools used when making them. We therefore aimed to describe and analyze 1) the processes used when making such decisions, 2) the associated decision situations, and 3) the use of and need for decision support tools in these processes, with a harwarder concept as case. Semi-structured interviews were conducted with respondents from six forestry organizations. Two theoretical frameworks were used to analyze the interviews, one for unstructured decision processes and one for decision situations. The respondents’ descriptions of their decision processes were consistent with those observed in other industries, and it was shown that decision-making could potentially be improved by investing more resources into diagnosing the problem at hand. The main objective in decision-making was to maximize economic criteria while satisfying threshold requirements relating to criteria such as operator well-being, soil rutting, and wood value. When facing large uncertainties, interviewees preferred to gather data through operational trials and/or scientific studies. If confronted with large uncertainties that could not be reduced, they proceeded with development only if the potential gains exceeded the estimated uncertainties, and implemented innovations in a stepwise manner. These results indicate a need for greater use of existing decision-support tools such as problem-structuring methods to enable more precise diagnoses, simulations to better understand new innovations, and optimization to better evaluate their theoretical large-scale potential.

• Jonsson, The Forestry Research Institute of Sweden (Skogforsk), Uppsala Science Park, SE-751 83 Uppsala, Sweden E-mail: rikard.jonsson@skogforsk.se
• Woxblom, The Forestry Research Institute of Sweden (Skogforsk), Uppsala Science Park, SE-751 83 Uppsala, Sweden E-mail: lotta.woxblom@skogforsk.se
• Björheden, The Forestry Research Institute of Sweden (Skogforsk), Uppsala Science Park, SE-751 83 Uppsala, Sweden E-mail: rolf.bjorheden@skogforsk.se
• Nordström, Swedish University of Agricultural Sciences, Department of Forest Resource Management, SE-901 83 Umeå, Sweden E-mail: eva-maria.nordstrom@slu.se
• Blagojevic, University of Novi Sad, Department of Water Management, Trg D. Obradovica 8, 21000 Novi Sad, Serbia E-mail: bosko.blagojevic@polj.edu.rs
• Lindroos, Swedish University of Agricultural Sciences, Department of Forest Biomaterials and Technology, SE-901 83 Umeå, Sweden E-mail: ola.lindroos@slu.se

Because today’s tree planting machines do a good job silviculturally, the Nordic forest sector is interested in finding ways to increase the planting machines’ productivity. Faster seedling reloading increases machine productivity, but that solution might require investments in specially designed seedling packaging. The objective of our study was to compare the cost-efficiency of cardboard box concepts that increase the productivity of tree planting machines with that of today’s two most common seedling packaging systems in southern Sweden. We modelled the total cost of these five different seedling packaging systems using data from numerous sources including manufacturers, nurseries, contractors, and forest companies. Under these southern Swedish conditions, the total cost of cardboard box concepts that increase the productivity of intermittently advancing tree planting machines was higher than the cost of the cultivation tray system (5–49% in the basic scenario). However, the conceptual packaging system named ManBox_fast did show promise, especially with increasing primary transport distances and increased planting machine productivities and hourly costs. Thus, our results show that high seedling packing density is of fundamental importance for cost-efficiency of cardboard box systems designed for mechanized tree planting. Our results also illustrate how different factors in the seedling supply chain affect the cost-efficiency of tree planting machines. Consequently, our results underscore that the key development factor for mechanized tree planting in the Nordic countries is the development of cost-efficient seedling handling systems between nurseries and planting machines.

• Ersson, SLU, School of Forest Management, SE-739 21 Skinnskatteberg, Sweden https://orcid.org/0000-0003-2442-7482 E-mail: back.tomas.ersson@slu.se
• Sundblad, Skogforsk, Uppsala Science Park, SE-751 83 Uppsala, Sweden E-mail: lars-goran.sundblad@skogforsk.se
• Manner, Skogforsk, Uppsala Science Park, SE-751 83 Uppsala, Sweden https://orcid.org/0000-0002-4982-3855 E-mail: jussi.manner@skogforsk.se

The natural northern distribution limit for pedunculate oak (Quercus robur L.) is in southern Finland. We hypothesized that the maximum frost hardiness (FH_max) in the winter limited the cultivation of oaks in northern latitudes. We tested the hypothesis with controlled freezing tests in midwinter. The acorns for the experiment were collected from the four main oak populations in southernmost Finland. The seedlings were raised in the nursery, frost hardened in field conditions, and then moved to a growth chamber at –2 °C on two occasions in winter and tested for FH_max in controlled freezing tests. Frost hardiness was assessed by differential thermal analysis (DTA) based on the low temperature exotherm (LTE) and relative electrolyte leakage (REL) of the stem, and visual damage scoring (VD) of the buds and stem. The initiation and peak of the LTE took place at an average of –41 °C and –43 °C respectively, without differences among the populations. The variation in the initiation and peak of the LTE was high, ranging from –34.6 °C to –45.5 °C and from –37.1 °C to –46.9 °C respectively. According to the REL method, the frost hardiness of the populations ranged from –44.0 °C to –46.4 °C in February and from –40.6 °C to –41.6 °C in March, without significant differences among the populations. According to VD, the bud was the least frost hardy organ, with FH between –19 °C and –33 °C, depending on population and assessment time. We conclude that the maximum hardiness may set the limit for the distribution of pedunculate oak northwards, but the high within-population variation offers potential to breed more frost hardy genotypes.

• Repo, Natural Resources Institute Finland (Luke), Natural Resources, Yliopistokatu 6b, FI-80100 Joensuu, Finland https://orcid.org/0000-0002-7443-6275 E-mail: tapani.repo@luke.fi
• Volanen, Kalevankatu 4b B21, FI-80110 Joensuu, Finland E-mail: virva.volanen@siunsote.fi
• Pulkkinen, Natural Resources Institute Finland (Luke), Production systems, Latokartanonkaari 9, FI-00790 Helsinki, Finland https://orcid.org/0000-0002-1643-7691 E-mail: pertti.pulkkinen@luke.fi

For constructing growth and yield models the concept of site index as measure of productivity is crucial. Here, we use nonlinear mixed-effects models (NLME) with random individual effects and nonlinear models with dummy variables as fixed individual effects (NLFE) to fit mechanistic growth functions to stem analysis data of the economically most important tree species in Zhongtiaoshan forest region, China. The Richards and Lundqvist function are formulated into five dynamic equations (R1, R2, L1, L2 and L3) applying the generalized algebraic difference approach (GADA), which inherit polymorphism, varying asymptotes and base-age invariance. According to Akaike information criterion the R1 model as NLFE fits height growth data of Pinus tabuliformis Carrière, Pinus armandii Franch., Quercus liaotungensis Koidz., Quercus aliena Blume and Betula platyphylla Sukaczev best, while for Quercus variabilis Blume R2 as NLFE fits height growth data best. For Larix principis-rupprechtii Mayr L1 as NLME has been selected as best model, as R1 and R2 both as NLFE and NLME are not extrapolating the comparably short length of height growth data well enough. However, according to the root mean square error and bias differences between model fits of both the selected equation and the chosen model fitting approach are not so clear. Presented families of height growth curves serve as planning tools to identify site index and therefore assess productivity of forest stands in the studied region. A direct comparison of the productivity of forest stands of the same tree species is possible due to base-age invariance of the selected models.

• Sprengel, Chair of Forest Growth and Dendroecology, Albert-Ludwigs-University Freiburg, Tennenbacher Str. 4, 79106 Freiburg, Germany https://orcid.org/0000-0002-6332-7911 E-mail: lars.sprengel@iww.uni-freiburg.de
• Spiecker, Chair of Forest Growth and Dendroecology, Albert-Ludwigs-University Freiburg, Tennenbacher Str. 4, 79106 Freiburg, Germany E-mail: instww@uni-freiburg.de
• Wu, Research Institute of Forest Policy and Information, Chinese Academy of Forestry, No. 1 Dongxiaofu, Haidian District, Beijing 100091, China E-mail: shuirongwu@126.com

Forestry and forest industries are important for regional income and employment in Norway as well as in most North European countries, but few studies exist about factors affecting the timber supply at regional level. The main objective of this study is to estimate aggregated regional timber supply elasticities for six regions in Norway. Thereby we also test for regional differences, focusing on wood prices, standing stock volume and interest rate as explanatory variables. We have used three different statistical models (fixed and random effects panel models and first difference models) on regional data from the Norwegian forest inventory on standing volume and official statistics on harvested volumes, interest rate and prices of sawlogs and pulpwood for the period 1996–2016. Statistically significant different price elasticities are found in 12 out of total 15 pairs of regions. The price elasticity was lower and the volume elasticity higher in the western region compared to the other regions. The first difference models are best with respect to specification tests. The use of region specific price elasticities gives slightly better fit for the panel data models than using a uniform price parameter. The results show that the econometric specification influence the parameter values, and it is thus complicated to directly compare results in different timber supply studies. Regional differences in timber supply are important to consider.

• Rørstad, Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway E-mail: per.kristian.rorstad@nmbu.no
• Solberg, Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway E-mail: birger.solberg@nmbu.no
• Trømborg, Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway E-mail: erik.tromborg@nmbu.no

Since the 1990’s, forest resource maps and small area estimates have been produced by combining national forest inventory (NFI) field plot data, optical satellite images and numerical map data using a non-parametric k-nearest neighbour method. In Finland, thematic maps of forest variables have been produced by the means of multi-source NFI (MS-NFI) for eight to ten times depending on the geographical area, but the resulting time series have not been systematically utilized. The objective of this study was to explore the possibilities of the time series for monitoring the key ecosystem condition indicators for forests. To this end, a contextual Mann-Kendall (CMK) test was applied to detect trends in time-series of two decades of thematic maps. The usefulness of the observed trends may depend both on the scale of the phenomena themselves and the uncertainties involved in the maps. Thus, several spatial scales were tested: the MS-NFI maps at 16 × 16 m² pixel size and units of 240 × 240 m², 1200 × 1200 m² and 12  000 × 12  000 m² aggregated from the MS-NFI map data. The CMK test detected areas of significant increasing trends of mean volume on both study sites and at various unit sizes except for the original thematic map pixel size. For other variables such as the mean volume of tree species groups, the proportion of broadleaved tree species and the stand age, significant trends were mostly found only for the largest unit size, 12  000 × 12  000 m². The multiple testing corrections decreased the amount of significant p-values from the CMK test strongly. The study showed that significant trends can be detected enabling indicators of ecosystem services to be monitored from a time-series of satellite image-based thematic forest maps.

• Katila, Natural Resources Institute Finland (Luke), Bioeconomy and environment, Latokartanonkaari 9, FI-00790 Helsinki, Finland; https://orcid.org/0000-0001-6946-5736 E-mail: matti.katila@luke.fi
• Rajala, Natural Resources Institute Finland (Luke), Natural resources, Latokartanonkaari 9, FI-00790 Helsinki, Finland E-mail: tuomas.rajala@luke.fi
• Kangas, Natural Resources Institute Finland (Luke), Bioeconomy and environment, Yliopistokatu 6, FI-80100 Joensuu, Finland https://orcid.org/0000-0002-8637-5668 E-mail: annika.kangas@luke.fi

Simulation and modeling have become more common in forest biomass studies. Dynamic simulation has been used to study the supply chain of forest biomass with numerous different models. A robust predictive multi-year model requires biomass availability data, where annual variation is included spatially and temporally. This can be done by using data from enterprises, but in some cases relevant data is not accessible. Another option is to use forest inventory data to estimate biomass availability, but this data must be processed in the correct form to be utilized in the model. This study developed a method for preparing forest inventory data for a multi-year simulation supply model using the theoretical availability of feedstock. Methods for estimating quality changes during roadside storage are also presented, including a possible parameter estimation to decrease the amount of data needed. The methods were tested case by case using the inventory database “Biomass Atlas” and weather data from a weather station in Mikkeli, Finland. The data processing method for biomass allocation produced a reasonable quantity of stands and feedstock, having a realistic annual supply with variation for the demand point. The results of the study indicate that it is possible to estimate moisture content changes using weather data. The estimations decreased the accuracy of the model and, therefore, estimations should be kept minimal. The presented data preparation method can generate a supply of forest biomass for the simulation model, but the validity of the data must be ensured for correct model behavior.

• Aalto, Lappeenranta-Lahti University of Technology LUT, School of Energy Systems, Laboratory of Bioenergy, Lönnrotinkatu 7, FI-50100 Mikkeli, Finland https://orcid.org/0000-0002-7768-1145 E-mail: mika.aalto@lut.fi
• Korpinen, Lappeenranta-Lahti University of Technology LUT, School of Energy Systems, Laboratory of Bioenergy, Lönnrotinkatu 7, FI-50100 Mikkeli, Finland E-mail: olli-jussi.korpinen@lut.fi
• Ranta, Lappeenranta-Lahti University of Technology LUT, School of Energy Systems, Laboratory of Bioenergy, Lönnrotinkatu 7, FI-50100 Mikkeli, Finland https://orcid.org/0000-0001-5464-5136 E-mail: tapio.ranta@lut.fi

The effect of harvester operator tree selection or prior tree marking in thinning operations on satisfactory results and performance has been widely discussed. In harvester operator tree selection, the machine operator decides on the fly which trees are selected to remain or cut. The objective of the study was to analyze the effect of prior tree marking, thinning method and topping diameter on harvester performance in low-diameter thinning operations. The entire thinning operation was captured using video technology. Overall, 2.36 ha divided into 48 plots with 5202 trees were thinned with an average diameter at breast height (dbh) over bark for all plots of between 12.5 and 14.7 cm. In total, 3122 trees were harvested, resulting in 60% removal of stem number over all plots. The harvester achieved a mean productivity of 7.38 m³ PMH₀^–1 with 1.48 m³ PMH₀^–1 SEM, with stem volume having the major influence on harvesting productivity. Prior tree marking, topping and thinning method did not significantly affect productivity. Without prior tree marking by the foresters, harvesting removal was shifted toward lower diameters. Within the unmarked plots, 7.0% of the residual trees were damaged compared with 3.2% in marked plots.

• Holzleitner, University of Natural Resources and Life Sciences Vienna, Department of Forest and Soil Sciences, Institute of Forest Engineering, Peter-Jordan-Straße 82/3, A-1190 Vienna, Austria https://orcid.org/0000-0001-8489-3050 E-mail: franz.holzleitner@boku.ac.at
• Langmaier, University of Natural Resources and Life Sciences Vienna, Department of Forest and Soil Sciences, Institute of Silviculture, Peter-Jordan-Straße 82/3, A-1190 Vienna, Austria; Austrian Research Centre for Forests, Department of Forest Growth and Silviculture, Seckendorff Gudent Weg 8, A-1130 Vienna, Austria E-mail: magdalena.langmaier@bfw.gv.at
• Hochbichler, University of Natural Resources and Life Sciences Vienna, Department of Forest and Soil Sciences, Institute of Silviculture, Peter-Jordan-Straße 82/3, A-1190 Vienna, Austria E-mail: eduard.hochbichler@boku.ac.at
• Obermayer, University of Natural Resources and Life Sciences Vienna, Department of Forest and Soil Sciences, Institute of Forest Engineering, Peter-Jordan-Straße 82/3, A-1190 Vienna, Austria; Agricultural Technical School of Pyhra, Kyrnbergstraße 4, A-3143 Pyhra, Austria E-mail: bernhardt.obermayer@lfs-pyhra.ac.at
• Stampfer, University of Natural Resources and Life Sciences Vienna, Department of Forest and Soil Sciences, Institute of Forest Engineering, Peter-Jordan-Straße 82/3, A-1190 Vienna, Austria http://orcid.org/0000-0001-9350-2859 E-mail: karl.stampfer@boku.ac.at
• Kanzian, University of Natural Resources and Life Sciences Vienna, Department of Forest and Soil Sciences, Institute of Forest Engineering, Peter-Jordan-Straße 82/3, A-1190 Vienna, Austria http://orcid.org/0000-0002-1198-9788 E-mail: christian.kanzian@boku.ac.at

Fire as disturbance of forests has an important ecological and economical role in boreal and hemiboreal forests. The occurrence of forest fires is both climatically and anthropogenically determined and shifts in fire regimes are expected due to climate change. Although fire histories have been well documented in boreal regions, there is still insufficient information about fire occurrence in the Baltic States. In this study, spatio-temporal patterns and climatic drivers of forest fires were assessed by means of spatial and time-series analysis. The efficiency of Canadian Fire Weather (FWI) indices as indicators for fire activity was tested. The study was based on data from the literature, archives, and the Latvian State Forest service database. During the period 1922–2014, the occurrence and area affected by forest fires has decreased although the total area of forest land has nearly doubled, suggesting improvement of the fire suppression system as well as changes in socioeconomic situation. The geographical distribution of forest fires revealed two pronounced clusters near the largest cities of Riga and Daugavpils, suggesting dominance of human causes of ignitions. The occurrence of fires was mainly influenced by drought. FWI appeared to be efficient in predicting the fire occurrence: 23–34% of fires occurred on days with a high or extremely high fire danger class, which overall had a relative occurrence of only 4.3–4.6%. During the 20th century, the peak of fire activity shifted from May to April, probably due to global warming and socioeconomic reasons. The results of this study are relevant for forest hazard mitigation and development of fire activity prediction system in Latvia.

• Donis, LSFRI “Silava”, Rigas str. 111, Salaspils, Latvia, LV2169 E-mail: janis.donis@silava.lv
• Kitenberga, LSFRI “Silava”, Rigas str. 111, Salaspils, Latvia, LV2169 E-mail: mara.kitenberga@gmail.com
• Šņepsts, LSFRI “Silava”, Rigas str. 111, Salaspils, Latvia, LV2169 E-mail: guntars.snepsts@silava.lv
• Matisons, LSFRI “Silava”, Rigas str. 111, Salaspils, Latvia, LV2169 E-mail: robism@inbox.lv
• Zariņš, LSFRI “Silava”, Rigas str. 111, Salaspils, Latvia, LV2169 E-mail: juris.zarins@silava.lv
• Jansons, LSFRI “Silava”, Rigas str. 111, Salaspils, Latvia, LV2169 E-mail: aris.jansons@silava.lv

Being a logging contractor involves several uncertainties, amongst others, information quality in the work order received from customers. The information quality of work orders is of the utmost importance for logging contactors, in order to be able to plan and conduct work properly. The purpose of this paper is three-fold: 1) identifying work order information components in harvesting, 2) identifying work order information quality dimensions in harvesting and 3) assessing work order information quality in harvesting. The paper is based on interviews and a survey. Various interviews took place in Sweden with professionals within the harvesting industry as well as logging contractors, and thereafter a survey was developed. Random selection was conducted and 100 Swedish logging contractors were contacted by telephone in order to answer the survey, with a response rate of 82% from the sample. The paper concludes that the information quality dimension of accuracy concerns the individual work order information components, whereas timeliness is related to receiving the complete work orders. A factor analysis has been conducted with five factors emerging. The assessment of work order information quality in harvesting implies that the potential for improvement exists with regard to increasing the accuracy of the order information for the components of “Cleaning under story trees – not conducted” and “Cleaning under story trees – of low standard” as well as “Landing – size”, and “Landing – placement”. However, their effect on capacity is utilization needs to be explored.

• Gustafsson, Linnaeus University, School of Business and Economics, Department of Management Accounting and Logistics, 391 82 Kalmar, Sweden E-mail: asa.gustafsson@lnu.se

The aim of this study was to examine how well stem volume, above-ground biomass and dominant height can be predicted using nationwide airborne laser scanning (ALS) based regression models. The study material consisted of nine practical ALS inventory projects taken from different parts of Finland. We used field sample plots and airborne laser scanning data to create nationwide and regional models for each response variable. The final models had one or two ALS predictors, which were chosen based on the root mean square error (RMSE), and cross-validated. Finally, we tested how much predictions would improve if the nationwide models were calibrated with a small number of regional sample plots. Although forest structures differ among different parts of Finland, the nationwide volume and biomass models performed quite well (leave-inventory-area-out RMSE 22.3% to 33.8%, mean difference [MD] –13.8% to 18.7%) compared with regional models (leave-plot-out RMSE 20.2% to 26.8%). However, the nationwide dominant height model (RMSE 5.4% to 7.7%, MD –2.0% to 2.8%, with the exception of the Tornio region – RMSE 11.4%, MD –9.1%) performed nearly as well as the regional models (RMSE 5.2% to 6.7%). The results show that the nationwide volume and biomass models provided different means than real means at regional level, because forest structure and ALS device have a considerable effect on the predictions. Large MDs appeared especially in northern Finland. Local calibration decreased the MD and RMSE of volume and biomass models. However, the nationwide dominant height model did not benefit much from calibration.

• Kotivuori, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: eetu.kotivuori@uef.fi
• Korhonen, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: lauri.korhonen@uef.fi
• Packalen, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: petteri.packalen@uef.fi

Finnish wood harvesting contractors have been working in Russia since the 1990s and new entrepreneurs are still interested in starting operations there, even though Russia is not an easy business environment. This study identifies the most significant risks in contracting in Russia. Risks were identified through expert evaluation and a risk analysis was conducted by using a risk matrix. Possible preventative measures were assessed for the identified risks. Some risks were found to be common in Russia and Finland, for example a limited number of clients, dependency on a few clients, and weak negotiating positions. A stable amount of work, i.e. the availability of stands for harvesting, was also a challenge on the both sides of border. Typical problems in Russia were breaches of contract, especially disagreements on wood measurement and payment delays, potentially causing serious economic losses. Specific to Russia were problems related to machine service and spare parts, as well as security issues. The professional skills of machine operators, as well as changing work motivation were risks in Russia. Cultural differences lead to more challenging supervision and management of staff. Among the external factors, the most challenging in Russia were unhealthy competition in the marketplace and non-transparent and the unpredictable procedures of the authorities. In Russia problems caused by seasonality are amplified by the sparse road network and longer downtime. The revealed specific features of the Russian business environment can help Finnish wood harvesting companies to plan a risk management process for operations in Russia.

• Karvinen, Natural Resources Institute Finland (Luke), Economics and society, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: sari.karvinen@luke.fi
• Nummelin, Natural Resources Institute Finland (Luke), Green technology, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: tuomas.nummelin@luke.fi

• Kreutz, Department of Forest Sciences, University of Helsinki, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: andreas.kreutz@wald-rpl.de
• Aakala, Department of Forest Sciences, University of Helsinki, P.O. Box 27, FI-00014 University of Helsinki, Finland http://orcid.org/0000-0003-0160-6410 E-mail: tuomas.aakala@helsinki.fi
• Grenfell, Department of Forest Sciences, University of Helsinki, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: russell.grenfell@gmail.com
• Kuuluvainen, Department of Forest Sciences, University of Helsinki, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: timo.kuuluvainen@helsinki.fi

• Miranda, Centro de Estudos Florestais, Instituto Superior de Agronomia, Universidade Lisboa, 1349-017 Lisboa, Portugal E-mail: Imiranda@isa.ulisboa.pt
• Gominho, Centro de Estudos Florestais, Instituto Superior de Agronomia, Universidade Lisboa, 1349-017 Lisboa, Portugal E-mail: Jgominho@isa.utl.pt
• Pereira, Centro de Estudos Florestais, Instituto Superior de Agronomia, Universidade Lisboa, 1349-017 Lisboa, Portugal E-mail: Hpereira@isa.utl.pt

• Ersson, Department of Forest Biomaterials and Technology, SLU, SE-90183 Umeå, Sweden E-mail: back.tomas.ersson@slu.se
• Bergsten, Department of Forest Biomaterials and Technology, SLU, SE-90183 Umeå, Sweden E-mail: urban.bergsten@slu.se
• Lindroos, Department of Forest Biomaterials and Technology, SLU, SE-90183 Umeå, Sweden E-mail: ola.lindroos@slu.se

• Zamora-Cristales, Department of Forest Engineering, Resources, and Management, College of Forestry, Oregon State University, 280 Peavy Hall, Corvallis, OR 97331, USA E-mail: rene.zamora@oregonstate.edu
• Boston, Department of Forest Engineering, Resources, and Management, College of Forestry, Oregon State University, 280 Peavy Hall, Corvallis, OR 97331, USA E-mail: kevin.boston@oregonstate.edu
• Sessions, Department of Forest Engineering, Resources, and Management, College of Forestry, Oregon State University, 280 Peavy Hall, Corvallis, OR 97331, USA E-mail: john.sessions@oregonstate.edu
• Murphy, Waiariki Institute of Technology, Rotorua, New Zealand E-mail: glen.murphy@waiariki.ac.nz

• Järvinen, Department of Industrial Engineering and Management, Aalto University, P.O.Box 15500, FI-00076 Aalto, Finland E-mail: joonas.jarvinen@aalto.fi
• Linnakangas, Department of Industrial Engineering and Management, Aalto University, P.O.Box 15500, FI-00076 Aalto, Finland E-mail: jl@nn.fi

• Ersson, Swedish University of Agricultural Sciences, Department of Forest Resource Management, SE-90183 Umeå, Sweden E-mail: back.tomas.ersson@slu.se
• Bergsten, Swedish University of Agricultural Sciences, Department of Forest Resource Management, SE-90183 Umeå, Sweden E-mail: ub@nn.se
• Lindroos, Swedish University of Agricultural Sciences, Department of Forest Resource Management, SE-90183 Umeå, Sweden E-mail: ol@nn.se

• Macias, Oregon State University, Department of Wood Science and Engineering, 119 Richardson Hall, Corvallis, OR 97331, USA E-mail: natalie.macias@gmail.com
• Knowles, Oregon State University, Department of Wood Science and Engineering, 119 Richardson Hall, Corvallis, OR 97331, USA E-mail: chris.knowles@oregonstate.edu

• Roos, Swedish University of Agricultural Sciences, Department of Forest Products, P.O. Box 7008, SE-750 07 Uppsala, Sweden E-mail: anders.roos@sprod.slu.se
• Woxblom, Swedish University of Agricultural Sciences, Department of Forest Products, P.O. Box 7008, SE-750 07 Uppsala, Sweden E-mail: lw@nn.se
• McCluskey, Swedish University of Agricultural Sciences, Department of Forest Products, P.O. Box 7008, SE-750 07 Uppsala, Sweden E-mail: dm@nn.se

• Windisch, Finnish Forest Research Institute, Joensuu Research Unit, Yliopistokatu 6, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: johannes.windisch@metla.fi
• Sikanen, University of Eastern Finland, School of Forest Science, Yliopistokatu 7, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: ls@nn.fi
• Röser, Finnish Forest Research Institute, Joensuu Research Unit, Yliopistokatu 6, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: dr@nn.fi
• Gritten, University of Eastern Finland, School of Forest Science, Yliopistokatu 7, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: dg@nn.fi

• Jacobson, Skogforsk, Uppsala Science Park, SE-75183 Uppsala, Sweden E-mail: staffan.jacobson@skogforsk.se
• Pettersson, Skogforsk, Uppsala Science Park, SE-75183 Uppsala, Sweden E-mail: fp@nn.se

• Moilanen, Finnish Forest Research Institute, Muhos and Parkano Research Units, Finland E-mail: mikko.moilanen@metla.fi
• Saarinen, Finnish Forest Research Institute, Muhos and Parkano Research Units, Finland E-mail: ms@nn.fi
• Silfverberg, Finnish Forest Research Institute, Muhos and Parkano Research Units, Finland E-mail: ks@nn.fi

• Uotila, Finnish Forest Research Institute, Suonenjoki, Finland E-mail: karri.uotila@metla.fi
• Rantala, Finnish Forest Research Institute, Suonenjoki, Finland E-mail: jr@nn.fi
• Saksa, Finnish Forest Research Institute, Suonenjoki, Finland E-mail: ts@nn.fi
• Harstela, Finnish Forest Research Institute, Suonenjoki, Finland E-mail: ph@nn.fi

• Gan, Department of Ecosystem Science and Management, Texas A&M University, Texas, USA E-mail: j-gan@tamu.edu
• Smith, Faculty of Forestry, University of Toronto, Ontario, Canada E-mail: cts@nn.ca

• Oikari, Karelwood, Kontiolahti, Finland E-mail: markku.oikari@karelwood.com
• Kärhä, Metsäteho Oy, Helsinki, Finland E-mail: kk@nn.fi
• Palander, University of Eastern Finland, Faculty of Science and Forestry, Joensuu, Finland E-mail: tp@nn.fi
• Pajuoja, Metsäteho Oy, Helsinki, Finland E-mail: hp@nn.fi
• Ovaskainen, University of Eastern Finland, Faculty of Science and Forestry, Joensuu, Finland E-mail: ho@nn.fi

• Korpela, University of Helsinki, Department of Forest Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: ilkka.korpela@helsinki.fi
• Ørka, Norwegian University of Life Sciences, Department of Ecology and Natural Resource Management, P.O.Box 5003, NO-1432 Ås, Norway E-mail: hoo@nn.no
• Maltamo, University of Eastern Finland, School of Forest Science, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: mm@nn.fi
• Tokola, University of Eastern Finland, School of Forest Science, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: tt@nn.fi
• Hyyppä, Finnish Geodetic Institute, Department of Photogrammetry and Remote Sensing, P.O.Box 15, FI-02431 Masala, Finland E-mail: jh@nn.fi

• Persson, Forestry Research Institute of Sweden, Sävar, Sweden E-mail: torgny.persson@skogforsk.se
• Andersson, Forestry Research Institute of Sweden, Sävar, Sweden E-mail: ba@nn.se
• Ericsson, Forestry Research Institute of Sweden, Sävar, Sweden E-mail: te@nn.se

• Doi, AFE Building, School of Environment, Resources and Development, Asian Institute of Technology, Pathumthani 12120, Thailand E-mail: roird@aeiou.pt
• Ranamukhaarachchi, AFE Building, School of Environment, Resources and Development, Asian Institute of Technology, Pathumthani 12120, Thailand E-mail: slr@nn.th

• Eskelson, Oregon State University, Department of Forest Engineering, Resources and Management, 204 Peavy Hall, Corvallis, Oregon 97331, USA E-mail: bianca.eskelson@oregonstate.edu
• Barrett, Oregon State University, Department of Forest Engineering, Resources and Management, 204 Peavy Hall, Corvallis, Oregon 97331, USA E-mail: tmb@nn.us
• Temesgen, Oregon State University, Department of Forest Engineering, Resources and Management, 204 Peavy Hall, Corvallis, Oregon 97331, USA E-mail: ht@nn.us

• Nuutinen, European Forest Institute, Torikatu 34, FI-80100 Joensuu, Finland E-mail: tuula.nuutinen@efi.int
• Kilpeläinen, University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: ak@nn.fi
• Hirvelä, Finnish Forest Research Institute, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: hh@nn.fi
• Härkönen, Finnish Forest Research Institute, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: kh@nn.fi
• Ikonen, University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: vpi@nn.fi
• Lempinen, Finnish Forest Research Institute, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: rl@nn.fi
• Peltola, University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: hp@nn.fi
• Wilhelmsson, Skogforsk, Uppsala Science Park, SE-751 83 Uppsala, Sweden E-mail: lw@nn.fi
• Kellomäki, University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: sk@nn.fi

• Kindermann, International Institute for Applied Systems Analysis, Laxenburg, Austria E-mail: kinder@iiasa.ac.at
• McCallum, International Institute for Applied Systems Analysis, Laxenburg, Austria E-mail: im@nn.at
• Fritz, International Institute for Applied Systems Analysis, Laxenburg, Austria E-mail: sf@nn.at
• Obersteiner, International Institute for Applied Systems Analysis, Laxenburg, Austria E-mail: mo@nn.at

• Vohland, University of Trier, Faculty of Geography and Geosciences, Remote Sensing Department, Trier, Germany E-mail: mv@nn.de
• Stoffels, University of Trier, Faculty of Geography and Geosciences, Remote Sensing Department, Trier, Germany E-mail: js@nn.de
• Hau, University of Trier, Faculty of Geography and Geosciences, Remote Sensing Department, Trier, Germany E-mail: ch@nn.de
• Schüler, Research Institution for Forest Ecology and Forestry (FAWF), Department of Forest Growth and Silviculture, Trippstadt, Germany E-mail: gs@nn.de

• Renou-Wilson, University College Dublin, Dublin, Ireland E-mail: frw@nn.ie
• Farrell, University College Dublin, Dublin, Ireland E-mail: epf@nn.ie

• Roturier, SLU, Vindeln Experimental Forests, Svartberget Fältstation, SE-922 91 Vindeln, Sweden E-mail: samuel.roturier@esf.slu.se
• Bäcklund, E-mail: sb@nn.se
• Sundén, E-mail: ms@nn.se
• Bergsten, SLU, Dept of Forest Ecology, SE-901 83 Umeå, Sweden E-mail: ub@nn.se

• Kyllönen, Department of Social and Moral Philosophy, P.O. Box 9, FI-00014 University of Helsinki, Finland E-mail: simo.kyllonen@helsinki.fi
• Colpaert, University of Joensuu, Department of Geography, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: ac@nn.fi
• Heikkinen, Taida, P.O. Box 1000, FI-90014 University of Oulu, Finland E-mail: hh@nn.fi
• Jokinen, Finnish Forest Research Institute, Kolari Research Unit, Muoniontie 21 A, FI-95900 Kolari, Finland E-mail: mj@nn.fi
• Kumpula, Finnish Game and Fisheries Research Institute, Reindeer Research Station, Toivoniementie 246, FI-99910 Kaamanen, Finland E-mail: jk@nn.fi
• Marttunen, Finnish Environment Institute, P.O. Box 140, FI-00251 Helsinki, Finland E-mail: mk@nn.fi
• Muje, Department of Biological and Environmental Science, P.O. Box 35, FI-40014 University of Jyväskylä, Finland E-mail: km@nn.fi
• Raitio, Department of Social and Policy, University of Joensuu, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: kr@nn.fi

• Lapointe, Université de Sherbrooke, Département de biologie, 2500 boulevard de l’Université, Sherbrooke, QC, Canada J1K 2R1 E-mail: bl@nn.ca
• Bradley, Université de Sherbrooke, Département de biologie, 2500 boulevard de l’Université, Sherbrooke, QC, Canada J1K 2R1 E-mail: robert.bradley@usherbrooke.ca
• Parsons, Université de Sherbrooke, Département de biologie, 2500 boulevard de l’Université, Sherbrooke, QC, Canada J1K 2R1 E-mail: wp@nn.ca
• Brais, UQAT, 445 boulevard Université, Rouyn-Noranda, QC, Canada J9X 5E4 E-mail: sb@nn.ca

• Hyvönen, Finnish Forest Research Institute, Joensuu Research Unit, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: pekka.hyvonen@metla.fi
• Anttila, University of Joensuu, Faculty of Forestry, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: pa@nn.fi

• Akbulut, Istanbul University, Faculty of Forestry, Bahcekoy, TR-34473 Istanbul, Turkey E-mail: ta@nn.tr
• Ayrilmis, Istanbul University, Faculty of Forestry, Bahcekoy, TR-34473 Istanbul, Turkey E-mail: nadiray@istanbul.edu.tr

• Repo, The Finnish Forest Research Institute, Joensuu Research Centre, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: tapani.repo@metla.fi
• Laukkanen, University of Joensuu, Department of Physics, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: jl@nn.fi
• Silvennoinen, University of Joensuu, Department of Physics, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: rs@nn.fi

• Mehtätalo, Finnish Forest Research Institute, Joensuu Research Centre, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: lauri.mehtatalo@metla.fi

• Rouvinen, University of Joensuu, Faculty of Forestry, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: seppo.rouvinen@joensuu.fi
• Rautiainen, University of Joensuu, Faculty of Forestry, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: ar@nn.fi
• Kouki, University of Joensuu, Faculty of Forestry, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: jk@nn.fi

• Jacobson, The Forestry Research Institute of Sweden, Uppsala Science Park, SE-75183 Uppsala, Sweden E-mail: staffan.jacobson@skogforsk.se

• Kaunisto, Finnish Forest Research Institute, Parkano Research Station, Kaironiementie 54, FIN-39700 Parkano, Finland E-mail: seppo.kaunisto@metla.fi
• Sarjala, Finnish Forest Research Institute, Parkano Research Station, Kaironiementie 54, FIN-39700 Parkano, Finland E-mail: ts@nn.fi

• Pérez Cordero, Centro Agronómico Tropical de Investigación y Enseñanza (CATIE), Turrialba, Costa Rica E-mail: diegoperez@costarricense.cr
• Kanninen, Center for International Forestry Research (CIFOR), Bogor, Indonesia E-mail: mk@nn.id

• Dzierzon, Institut für Forstliche Biometrie und Informatik, Universität Göttingen, Büsgenweg 4, D-37077 Göttingen, Germany E-mail: hdzierz@gwdg.de
• Sievänen, The Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: rs@nn.fi
• Kurth, Institut für Informatik, Brandenburgische Technische Universität Cottbus, P.O. Box 101344, D-03013 Cottbus, Germany E-mail: wk@nn.de
• Perttunen, The Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: jp@nn.fi
• Sloboda, Institut für Forstliche Biometrie und Informatik, Universität Göttingen, Büsgenweg 4, D-37077 Göttingen, Germany E-mail: bs@nn.de

• Lindström, University of Canterbury, School of Forestry, Private Bag 4800, Christchurch, New Zealand E-mail: lindstromhakan@netscape.net

• Rouvinen, University of Joensuu, Faculty of Forestry, P.O. Box 111, FIN-80101 Joensuu, Finland E-mail: seppo.rouvinen@forest.joensuu.fi
• Kuuluvainen, University of Helsinki, Department of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland E-mail: tk@nn.fi
• Siitonen, Finnish Forest Research Institute, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: juha.siitonen@metla.fi

• Lindström, University of Canterbury, School of Forestry, Private Bag 4800, Christchurch, New Zealand E-mail: lindstromhakan@netscape.net

• Lindholm, Saima Centre for Environmental Sciences, University of Joensuu, Linnankatu 11, FIN-57130 Savonlinna, Finland E-mail: ml@nn.fi
• Lehtonen, Finnish Forest Research Institute, Joensuu Research Station, Box 68, FIN-80101 Joensuu, Finland E-mail: hl@nn.fi
• Kolström, Finnish Forest Research Institute, Joensuu Research Station, Box 68, FIN-80101 Joensuu, Finland E-mail: tk@nn.fi
• Meriläinen, Saima Centre for Environmental Sciences, University of Joensuu, Linnankatu 11, FIN-57130 Savonlinna, Finland E-mail: jm@nn.fi
• Eronen, Department of Geology, Division of Geology and Palaeontology, Box 11, FIN-00014 University of Helsinki, Finland E-mail: me@nn.fi
• Timonen, Finnish Forest Research Institute, Rovaniemi Research Station, Box 16, FIN-96301 Rovaniemi, Finland E-mail: mt@nn.fi

• Eskelinen, Lappeenranta University of Technology, Department of Electrical Engineering, P.O. Box 20, FIN-53851 Lappeenranta, Finland E-mail: ari.eskelinen@pp.inet.fi
• Eskelinen, Lappeenranta University of Technology, Department of Electrical Engineering, P.O. Box 20, FIN-53851 Lappeenranta, Finland E-mail: he@nn.fi

• Kangas, Finnish Forest Research Institute, Kannus Research Station, P.O. Box 44, FIN-69101 Kannus, Finland E-mail: annika.kangas@metla.fi
• Kangas, Finnish Forest Research Institute, Kannus Research Station, P.O. Box 44, FIN-69101 Kannus, Finland E-mail: jk@nn.fi

• Niskanen, European Forest Institute, Torikatu 34, FIN-80101 Joensuu, Finland E-mail: anssi.niskanen@efi.fi

• Leskinen, Finnish Forest Research Institute, Kannus Research Station, P.O. Box 44, FIN-69101 Kannus, Finland E-mail: pekka.leskinen@metla.fi
• Kangas, Finnish Forest Research Institute, Kannus Research Station, P.O. Box 44, FIN-69101 Kannus, Finland E-mail: jk@nn.fi

Spectral mixture analysis was used to estimate the contribution of woody elements to tree level reflectance from airborne hyperspectral data in boreal forest stands in Finland. Knowledge of the contribution of woody elements to tree or forest reflectance is important in the context of lea area index (LAI) estimation and, e.g., in the estimation of defoliation due to insect outbreaks, from remote sensing data. Field measurements from four Scots pine (Pinus sylvestris L.), five Norway spruce (Picea abies (L.) Karst.) and four birch (Betula pendula Roth and Betula pubescens Ehrh.) dominated plots, spectral measurements of needles, leaves, bark, and forest floor, airborne hyperspectral as well as airborne laser scanning data were used together with a physically-based forest reflectance model. We compared the results based on simple linear combinations of measured bark and needle/leaf spectra to those obtained by accounting for multiple scattering of radiation within the canopy using a physically-based forest reflectance model. The contribution of forest floor to reflectance was additionally considered. The resulted mean woody element contribution estimates varied from 0.140 to 0.186 for Scots pine, from 0.116 to 0.196 for birches and from 0.090 to 0.095 for Norway spruce, depending on the model used. The contribution of woody elements to tree reflectance had a weak connection to plot level forest variables.

• Kuusinen, Department of Built Environment, School of Engineering, Aalto University, P.O. Box 14100, FI-00076 Aalto, Finland E-mail: nea.kuusinen@aalto.fi
• Hovi, Department of Built Environment, School of Engineering, Aalto University, P.O. Box 14100, FI-00076 Aalto, Finland E-mail: aarne.hovi@aalto.fi
• Rautiainen, Department of Built Environment, School of Engineering, Aalto University, P.O. Box 14100, FI-00076 Aalto, Finland; Department of Electronics and Nanoengineering, School of Electrical Engineering, Aalto University, P.O. Box 15500, FI-00076 Aalto, Finland https://orcid.org/0000-0002-6568-3258 E-mail: miina.a.rautiainen@aalto.fi

• Kangas, Finnish Forest Research Institute, Joensuu Research Centre, P.O. Box 44, FIN-69101 Kannus, Finland E-mail: jyrki.kangas@metla.fi
• Store, Finnish Forest Research Institute, Kannus Research Station, P.O. Box 44, FIN-69101 Kannus, Finland E-mail: rs@nn.fi