Articles containing the keyword 'classification'

Fresh and herb-rich upland forest sites in the north-western part of the central boreal vegetation zone in Finland were studied with respect to vegetation structure and vegetation-environment relationships (soil, stand characteristics). Two fresh heath vegetation data sets, one from the northern boreal zone and the other from the central boreal zone, were compared with the data of this study using multivariate methods.

The variation in heath forest vegetation within the climatically uniform area was mainly determined by the fertility of the soil (primarily Ca and Mg) and the stage of stand development. N, P and K content of the humus layer varied little between the vegetation classes. Fertile site types occurred, in general, on coarse-textured soils than infertile site types, may be due to the fact that the sample plots were located in various bedrock and glacial till areas, i.e. to sampling effects.

The place of the vegetational units of the study area in the Finnish forest site type system is discussed. The vegetation of the area has features in common with the northern boreal zone as well as the southern part of the central boreal vegetation zone. The results lend some support to the occurrence of a northern Myrtillus type or at least that intermediate form of fresh and herb-rich mineral soil sites commonly occur in the studied area. It is argued that the older name Dryopteris-Myrtillus type is more suitable than Geranium-Oxalis-Myrtillus type for herb-rich heath sites in the study area.

• Lehtelä, E-mail: ml@mm.unknown
• Hotanen, E-mail: jh@mm.unknown
• Sepponen, E-mail: ps@mm.unknown

It was examined whether the present site classification method, and especially its applicability to site productivity estimation, could be improved in upland Scots pine (Pinus sylvestris L.) forests in Southern Finland by developing a classification key based on Two-way Indicator Species Analysis (TWINSPAN), and/or by inclusion of soil texture, stoniness and the humus layer depth more closely in the classification method. TWINSPAN clusters (TW) explained 71%, and forest site types (FST) 64% of the variation in site index (SI) (H₁₀₀). When soil texture (TEXT) was added to the regression model, the explanatory power increased to 82% (SI = TW + TW * TEXT) and to 80% (SI = FST + FST * TEXT), respectively. Soil texture alone explained 69% of the variation in site index. The influence of stoniness on site index was significant (P <0.05) on sorted medium sand soils and on medium and fine sand moraine soils. The thickness of the humus layer (2–6 cm) was not significantly (P=0.1) related to site index.

It is suggested that the proposed TWINSPAN classification cannot replace the present forest site type system in Scots pine stands in Southern Finland. However, the TWINSPAN key may be used to aid the identification of forest types. The observation of dominant soil texture within each forest type is recommended.

The PDF includes an abstract in Finnish.

• Nieppola, E-mail: jn@mm.unknown

A test sawing was made of 807 Scots pine (Pinus sylvestris L.) saw logs of varying size and quality. The most important knot characteristic affecting the value of sawn goods was the diameter of the thickest dry knot. The new minimum requirements for pine logs were proposed on the basis of top diameter of the log and the diameter of the thickest dry and living knot.

The PDF includes a summary in English

• Kärkkäinen, E-mail: mk@mm.unknown
• Halinen, E-mail: mh@mm.unknown

Vegetation data collected from a random sample of mature forest stands representing mesic upland forest sites in Southern Finland were analysed and classified using two-way indicator species analysis (TWINSPAN). The variation of some characteristics of the tree stand and soil fertility between the produced vegetation units were analysed statistically.

Both the species list and the sample list arranged by TWINSPAN reflects the overall site fertility considerably well. The results are in agreement with the main division of mesic forest sites in the Finnish forest site type classification: vegetation units which can be assigned to the Oxalis-Myrtillus site type are clearly separated from the remaining units, and the overall site fertility indicates a statistically significant difference. The within-type variation in the vegetation composition in the Oxalis-Myrtillus site type reflects the variation in site fertility, whereas the within-type variation in the Myrtillus site type is mainly caused by the tree stand factor.

The PDF includes a summary in Finnish.

• Kuusipalo, E-mail: jk@mm.unknown

As a subproblem in the joint Nordic Terrain-Machine Project the requirements set by forest road construction on the terrain classifications were studied during the summer 1973 in ten operations, in which either a bulldozer or an excavator method was used.

The most important terrain factors of the ground factors affecting the construction time of the road base were the so-called depth index and the moisture content of the soil, and in addition to these the amount of stumps as a ground roughness factor. These variables explained, however, only a rather minor part of the wide variation in the construction output of the practical operations.

The PDF includes a summary in English.

• Haarlaa, E-mail: rh@mm.unknown

The mobility of logging tractors was tested in the winter 1969 on difficult snow conditions to gather information for planning of logging operations and for logging machinery design. The tractors tested were Clark Ranger 666, Timberjack C, Valmet Terra, Ford Brunett 5000, Fiskars 510, BM-Volvo SM 660, BM Volvo SM 661, Ford Country 6, MF-Robur I and BM-Boxer T-350.

According to the results, there is a preference of tracked vehicles in difficult snow conditions compared to wheeled tractors. Ford Country with long and bearing full-tracks proved to have the best mobility. On downhill grades it was found significant differences between three-quarter-track-tractors and skidders, although the performance on level ground and uphill grades was relatively similar. The tracked vehicles can easier move on the packed snow layer and reach a higher speed.

The driving speed does not increase significantly until the density of snow has entirely changed through getting wet. Wet top layer of snow affects positively on driving, because it increases packing of the snow. Increasing density of the snow improves especially the mobility of broad-tired wheeled tractors. To be able to predict the driving speed of a tractor in winter working conditions one must know the depth of the snow layer and the density of the snow and the grade of the slope. In addition, the passages on the same route and the packing of the snow must be regarded.

The PDF includes a summary in English.

• Silvennoinen, E-mail: us@mm.unknown
• Haarlaa, E-mail: rh@mm.unknown

The article is a report from the meeting of the Section 32 of the IUFRO in Canada on September 15.–25. 1964, which three Finnish forestry experts participated. The theme of the meeting was classification of forest terrain.

The PDF includes a summary in English.

• Makkonen, E-mail: om@mm.unknown

The paper is a review on the topics of Symposium on forest types and forest ecosystems, held in connection to the IX internal botanical congress in Montreal in August 1959, the chairman of which was Ilmari Hustich. The article includes 18 preparatory papers that were distributed among the participants of the symposium. The common theme of the papers was the question of finding common platform for the different schools of forest types and forest ecosystems. In addition to the papers, the article includes a summary of the proceedings and discussions of the symposium.

The following papers were presented in the symposium:

Aichinger, E. Können wir eine gemeinsame Platform für die verscheidenen Schulen in der Waldtypenklassifikationen finden?

Arnborg, T. Can we find a common platform for the different schools of forest type classifications?

Dansereau, P. A combined structural and floristic approach to the definition of forest ecosystems.

Daubenmire, R. Some major problems in vegetation classification

Ellenberg, H. Können wir eine gemeinsame Platform für die verscheidenen Schulen in der Waldtypenklassifikationen finden?

Hills, G.A. Comparison of forest ecosystems (vegetation and soil) in different climatic zones

Kalela, A. Classification of the vegetation, especially of the forest, with particular reference to regional problems

Krajina, V.J. Can we find a common platform for the different schools of forest type classifications?

Kühler, A.W. Mapping tropical forest vegetation

Linteau, A. Y. a-t-il. Un terrain d’entente possible entre les différentes écoles au sujet de la classification de types forestiers?

Medvecka-Kornaś, A. Some problems of forest climaxes in Poland

Ovington, J.D. The ecosystem concept as aid to forest classification

Puri, G.S. The concept of climax in forest botany as applied in India

Rowe, J.S. Can we find a common platform for the different schools of forest type classifications?

Scamoni, A. Können wir eine gemeinsame Grundlage für die verscheidenen Schulen in der Waldtypenklassifikationen finden?

Sukachev, V.N. The correlation between the concept ’forest ecosystem’ and ’forest biogeocoenise’ and their importance for the classification of forests

Webb, L.J. A new attempt to classify Australian rain forest

• Heikurainen, E-mail: –
• Finnish Society of Forest Science, E-mail: –

Silva Fennica Issue 69 includes presentations held in 1948-1950 in the fourth professional development courses, arranged for foresters working in the Forest Service. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.

This presentation describes the uses and principles of different kinds of grading of saw logs.

• Heiskanen, E-mail: vh@mm.unknown

The Forest Research Institute of Finland has established permanent sample plots to survey the effect of thinnings on the stands. This study compares the development of tended and natural Scots pine (Pinus sylvestris L.) stands growing on three different forest types: Oxalis-Myrtillus, Vaccinium and Calluna site type. The effect of heavy thinning from below (Oxalis-Myrtillus and Vaccinium site types) and increment felling (Calluna site type) was assessed by dividing the trees of the stands in tree classification classes according to their crown storey and defects.

The results show that thinning from below and increment thinning increase the proportion of trees in the 1st crown storey, which is already large in the natural stands. Also the diameter distribution is more even and the mean diameter higher after the thinnings.

In Scots pine stands in natural state, volume increment per stem is highest in the 1st crown storey and diminishes strongly towards the lower crown storeys. Thinnings increased the increment. The study indicates that many of the objectives of the intermediate cuttings, including promoting the growth of the best trees and improving the quality of the stand, have in general been achieved. Consequently, the thinnings give means to achieve the most valuable yield in the stand.

The article includes a summary in English.

• Nyyssönen, E-mail: an@mm.unknown

The article contains three presentations given about forest type classification at the University of Tarto in Estonia. The article has an introduction, a part about the meaning of the natural classification of forest sites and up to now conducted studies on site classification. The second part presents the characteristics of plant communities and the forest types, and practical and theoretical meaning of forest types.

Classifying the forest sites is important in practical forestry, because the forest growth and forest valuation are dependent on the productivity of the soil. The classification of the sites for forest management purposes needs to result in classes that are easily distinguished in the forest. This then leads to forest management that best fits to a certain forest site. 

• Cajander, E-mail: ac@mm.unknown

The aim of the study is to find out 1) whether and how the original moor type can be found out based on vegetation regardless the phase of drainage; 2) whether the different phases of draining can be distinguished based on the vegetation; and 3) is it possible to classify the well drained moors into vegetation types that would reflect the productive capacity of the land.

The data consists of samples collected from ditched areas. There are 11 moor types from two climatic ditching zones. The results show that the original moor type can be determined based on vegetation, the phase of drainage can be determined under some limitations, and the classification for productivity can be done for practical purposes.    

The PDF contains a summary in Finnish. 

• Sarasto, E-mail: js@mm.unknown

One of the factors that influence if a peatland is suitable for draining is the time required until fellings bring income, even if it the discounting calculations has uncertainties. This article discusses the factors that affect the economic profitability of draining peatlands.

The profitability of draining increases the more the yield or increase of the yield exceeds the costs of draining. Estimation of the yield is in Finland based on the peatland type, which reflects production capacity of the site. In addition, the growing stock of the site can vary in peatlands within same peatland type. The density and size of ditches affects the draining costs. Thus, productivity based on a peatland type alone does not describe well enough the drainability of a peatland area.

In Finnish classification of site quality of the peatlands, the treeless bogs and rich fens have been given too high a class compared to well stocked spruce swamps and pine swamps. Also, the drainability of two spruce and pine swamps can differ markedly in economic point of view if the tree’s quality, volume and ability to recover differ. The article discusses different methods to assess profitability of draining that have been descibed in the previous studies. It is suggested that the classification of peatlands by their drainability should be more selective.

The PDF includes a summary in German.

• Keltikangas, E-mail: vk@mm.unknown

The plant populations of Finnish open bogs are typically formed of two layers. The layers normally consist of one or rarely two species. The structure of plant populations in open bogs is a consequence of the development where determining factors are different site requirements of the species, and the differences in the biotic vitality and capacity for reproduction.

Phytogenesis should be taken as a basic unit for describing the plant societies or vegetation of treeless bogs. However, acknowledging the sub-populations may be of advantage for describing the ecological, genetic and regional characters of open bogs.

The basic classification of open bogs must be done based on the ground layer. The more detailed classification follows mostly based on field layer, partly also based on the ground layer.

The PDF contains a summary in Finnish. 

• Paasio, E-mail: ip@mm.unknown

The article presents the characteristics of different vegetation areas (meadows and peatlands) by their distinctive vegetation. The study area is by the Barents Sea and is the northernmost part of continental European Russia. Different sites are classified by plant communities and/or vegetation units.

The article continues on the second PDF-file. 

• Kalela, E-mail: ak@mm.unknown

Earlier studies show that different kind of biological processes occur in the soil of different forest types. These differences may be due differences in microbiology of those soils. This article studies these differences.

Soil samples from five different forest types were collected from the Ruotsinkylä research forest in three different seasons: in January, March and September.

The amount of bacteria in the samples is at the lowest in March and highest in September.   During the winter more anaerobic bacteria were found. The amount of denitrifying bacteria is higher in the soil than amount of nitrifying bacteria.

The results indicate that the species composition of soil varies between the forest types in the same manner than the vegetation composition above the soil. However, this study is only a preliminary and more knowledge is needed about the discipline before practical implications can be drawn.

The PDF contains a summary in Finnish.  

• Svinhufvud, E-mail: vs@mm.unknown

The study is based on the measurements and observations made during summers 1927-1929 and 1932 on South- and West-Finnish high moors. The article aims to give an overview on the vegetation if the Finnish high moors. The study seeks to answer following questions: to what extent and what kind of characters of other moor types are present in high moors, to what extent occur the characteristics of high moors outside the high moor area, and what are the typical characteristics of high moors?

The article describes the different types of raised bogs and the plant topographic characters. The high moors in different parts of Finland differ from each other with their characteristics and vegetation that they are classified in three groups: high moors in south-west Finland, high moors of northern part of Satakunta-province, and high moors south-east Finland.    

The PDF contains a summary in Finnish.

• Paasio, E-mail: ip@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 discusses the different methods to classify forest sites and applies the methods to classify forests in Latvia. The three methods are: height-over-age classification, from standpoint of floristic (botanical- plant geographical standpoint), and forest types. A good classification method must: describe the main characters of a site illustratively, the classification units need to relate to each other, and the classification method is easy to use in practice. In contrast to other methods, by forest type classification the stand and the site are considered as whole and hence it is considered as the best of the three.

There is one classification system for the whole Latvia. The forests can be divided into permanent and transition types. In the permanent types the site factors stay rather unchanged and the site characters tally with the requirements of the dominant species. sites where the current tree species produces less than optimum growth are classified as transition types.

The forest types have changed over the time because of leaching of the nutrients from the soil.   

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

• Kirstein, E-mail: kk@mm.unknown

After critically reviewing earlier studies on soil properties and their influence on forest growth and yield, it seems that defining the forest yield could be possible by means of soil properties. To be able to do so, the site needs to be defined and delineated in some other way. It is also necessary to decide the right soil properties to study for the purpose.

For the classification of forest sites the results of soil analyses need to be compared with growth and yield data from the site. To further the practice of classification of forest sites by means of soil studies, four aspects need to be taken into account:

1)  the site needs to be delineated beforehand according its vegetation, preferable with Cajander’s forest type classification

2) the experiments about soil needs to be done for as many properties as possible

3) the studied sites need to be as representative as possible in their class

4) there are as many samples for one site as possible studied

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

• Aaltonen, E-mail: va@mm.unknown

The aim of the study is to define to which extent the productivity of seas in south Finland, and especially the production of animals in sea bottom, can be determined according the forest site classification given to the land areas around the sea, meaning that the productivity class is the same for the forest and the sea. The data for the study has been collected in state owned forests in Evo in middle Finland, in Karelia around the Finnish and Russian border and in southern parts of Karelia.

Where the forests are more barren, VT or Ct types, also the seas have lower productivity, they are oligotrophic or mesotrophic. However, the less barren surrounding forests are not a clear sign of the productivity of the sea. As a result the productivity level of a sea can be estimated relatively good by the fertility of the surrounding areas, though not in all cases. 

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

The PDF contains a summary in German.

• Valle, E-mail: kv@mm.unknown

To be able to exactly describe the similarities and differences of vegetation in certain areas, classifying the vegetation only in communities or formations is not enough. Therefore more classes are needed. The classification according the horizontal layers is based on the heights of plants and their relations to each other. Every population in one community has own area of height which extends to horizontal direction.

In comparison with populations the vegetation horizons create a biologically validated comparison of different vegetation groups and their parts. Defining the populations and vegetation horizons creates a division and systematization of plant communities on an ecological basis.       

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

• Kujala, E-mail: vk@mm.unknown

The article is a congratulatory letter to professor Cajander. The author describes the work of Cajander about forest site classification and its importance to the development of forest sciences not only in Finland but worldwide.

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

• Wappes, E-mail: lw@mm.unknown

The article contains tree lectures given in the meeting of the Geographical Society in Finland on February 25^th 1921.  The titles of the lectures are I Forest types in general, II Forest types as a basis for new growth and yield tables in Finland, and III Other research on forest types.  

The first lecture is a follow-up of the Cajander’s 1909 published article on forest types. It deepens the theory on forest types. The classification into forest types represents primarily different plant communities of ground cover. The types are named after the characteristic plant species, indicator plants, however, many other species appear in different abundance.

The second lecture represents the research proceedings of mensuration of forest stands of different types to compile yield tables for pine.  The forest types differ from each other distinctly on their growing preconditions, but inside one class the variation of the growing conditions is so small, that the classification can be used for yield tables, determining the basis of taxation and for classification of forest based on height over age.

The third lecture is a summary of other studies about forest type classification.  They confirm the results presented in earlier lectures. 

• Cajander, E-mail: ac@mm.unknown
• Ilvessalo, E-mail: yi@mm.unknown

The first part of the article presents an overview of peatlands and their classification on the basis of e.g. their nutrient content in Finland. The second part (a separate pdf file) represents the different types of peatland with their indicator plants in Finland. 

Peatlands can be classified in several ways, depending on the purpose of the classification. There are also differences whether an area is considered biologically or geographically as a peatland. For agricultural or forestry purposes the peatlands can be classified on the basis of their nutrient content.

Article also discusses the three ways of emergence of peatlands and the variations of water relations of peatlands.    

• Cajander, E-mail: ac@mm.unknown

The relationship between site characteristics and understorey vegetation composition was analysed with quantitative methods, especially from the viewpoint of site quality estimation. Theoretical models were applied to an empirical data set collected from the upland forests of Southern Finland comprising 104 sites dominated by Scots pine (Pinus sylvestris. L.) and 165 sites dominated by Norway spruce (Picea abies (L.) H. Karst.). Site index H₁₀₀ was used as an independent measure of site quality.

A new model for the estimation of site quality at sites with a known understorey vegetation composition was introduced. It is based on the application of Bayes’ theorem to the density function of site quality within the study area combined with the species-specific presence-absence response curves. The resulting probability density function may be used for calculating an estimate for the site variable

Using this method, a jackknife estimate of site index H₁₀₀ was calculated separately for pine- and spruce-dominated sites. The results indicated that the cross-validation root mean squared error (RMSE_cv) of the estimates improved from 2.98 m down to 2.34 m relative to the ”null” model (standard deviation of the sample distribution) in pine-dominated forests. In spruce-dominated forests RMSE_cv decreased from 3.94 m down to 3.19 m.

In order to assess these results, four other estimation methods based on understorey vegetation composition were applied to the same data set. The results showed that none of the methods was clearly superior to the others. In pine-dominated forests RMSE_cv varied between 2.34 and 2.47 m, and the corresponding range for spruce-dominated forest was from 3.13 to 3.57 m.

• Lahti, E-mail: tl@mm.unknown

Mineral soil sites where Scots pine (Pinus sylvestris L.) were suffering from Gremmeniella abietina die-back (Lagerb.) M. Morelet. were characterized and classified in Central Finland. The tree stand, ground vegetation, soil type and site topography were described in 163 sample plots in 16 stands. The sites were classified according to system developed by Cajander and numerically using TWINSPAN analysis based on the ground vegetation. The site topography of severely damaged stands was checked from colour infrared aerial photographs. The disease was most severe in depressions and frost pockets. Apart from topography no significant correlations were found between disease severity and site factors. No typical vegetational pattern of forest type of the severely affected stands could be detected. Most of the stands were growing on medium-coarse, unfertile soil with a rather thick humus layer.

The PDF includes a summary in Finnish.

• Sairanen, E-mail: as@mm.unknown

The vegetation and number of physical and chemical soil properties were studied on a random sample of closed upland forest stands in Southern Finland. The material consists of a total of 410 sample plots. Two-way indicator species analysis (TWINSPAN) was carried out in order to produce a hierarchical clustering of samples on the basis of the vegetation data. Discriminant analysis and analysis of variance were applied in order to find environmental correlations of the vegetation clustering.

The vegetation was found to indicate the nutrient regime of the humus layer well, but to a less extent the properties of the sub-soil. The understorey vegetation was found to be jointly dependent on the site fertility and on the properties of the tree stand, especially on the tree species composition. Although the forest vegetation appears to be distributed rather continuously along an axis of increasing site fertility, relatively unambiguous classification can be based on the appearance of indicator species and species groups.

The results of the study were interpreted as indication that operational site classification done using the vegetation is rather good method for classification in closed forest stands. Different methods produce relatively consistent, natural and ecologically interpretable classifications. The results also imply that the vegetation cover and the humus layer develop concurrently during the development of the ecosystem, but the differentiation of the site type is regulated simultaneously by a number of interacting factors ranging from mineralogical properties of the parent material to the topographical exposition of the site. As the plant cover depicts all these primary factors simultaneously, only a relatively rough ecological site classification can be based on the vegetation.

The PDF includes a summary in Finnish.

• Kuusipalo, E-mail: jk@mm.unknown

Fertility of surface peat from sedge pine mires was studied by measuring several edaphic growth factors: bulk density, volume weight of organic matter, ash content, acidity, electric conductivity, effective cation exchange capacity, degree of base saturation, and total contents of N, P, K, Ca and Mg. The 168 temporal sample plots were situated on virgin sedge mires in different parts of Finland, and the 30 permanent sample plots on two uniform sedge mires.

The results showed that peat bulk density and volume weight of organic matter tend to increase with increasing site quality. Ash content increased gradually in the site series from small sedge mire to the herb-rich sedge mire. The relationship between the total content of macronutrients in peat and the site quality is clear. The importance of bulk density in evaluating the site quality is further emphasized when taking into account its significant correlation to contents of N and P. The soil variables follow the accepted quality gradient of the site series. Consequently, the plant sociologically based site classification seems to reflect satisfactorily the average soil properties. However, the within site variation was significant.

• Westman, E-mail: cw@mm.unknown

The paper is the final report of the Inter-Nordic Terrain-machine Project (1972–1975). It deals with the requirements for a terrain classification for forestry, its factors and classes, and presents a terrain classification.

The mechanization of hauling, which took place in the field of forestry in the 1950's, added to the need for a terrain classification. Different terrain classifications based on different terrain factors have been developed in many countries. In the meeting of IUFRO Section 32 held in Montreal in 1964, it was found that a general system was needed for measuring and describing those terrain conditions having a significant influence on forest operations. The requirements for such a classification system are given in the paper. Because some of the requirements are contradictory, the classification must be a compromise. The most important factors from the forestry point of view are presented in the article.

The terrain classification presented in this report consists of two stages. The first stage is a primary terrain classification, in which terrain factors are measured or described objectively. The second is a secondary descriptive classification. Only factors essential to the activity in question are taken into account. After this, in a secondary functional stage, the requirements of the employer of the system, e.g., working method, machines etc., are also taken into account.

The PDF includes a summary in Finnish.

• Eriksson, E-mail: te@mm.unknown
• Nilsson, E-mail: gn@mm.unknown
• Skråmo, E-mail: gs@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

The article is the first part of a wider project aiming to study the measurement practices of stand’s height-over-age based classifications and to develop new methods for actually measuring the side index.  

The first part of the article presents the concepts of site indexing and discusses it with a mathematical model. The second part of the article examines the structure of site indexing system regarding the reliability of the method. Third part presents the factors affecting the method development and the fourth part discusses the possible site index classes and their characteristics.   

The PDF contains a summary in Finnish. 

• Kangas, E-mail: yk@mm.unknown

Current remote sensing methods can provide detailed tree species classification in boreal forests. However, classification studies have so far focused on the dominant tree species, with few studies on less frequent but ecologically important species. We aimed to separate European aspen (Populus tremula L.), a biodiversity-supporting tree species, from the more common species in European boreal forests (Pinus sylvestris L., Picea abies [L.] Karst., Betula spp.). Using multispectral drone images collected on five dates throughout one thermal growing season (May–September), we tested the optimal season for the acquisition of mono-temporal data. These images were collected from a mature, unmanaged forest. After conversion into photogrammetric point clouds, we segmented crowns manually and automatically and classified the species by linear discriminant analysis. The highest overall classification accuracy (95%) for the four species as well as the highest classification accuracy for aspen specifically (user’s accuracy of 97% and a producer’s accuracy of 96%) were obtained at the beginning of the thermal growing season (13 May) by manual segmentation. On 13 May, aspen had no leaves yet, unlike birches. In contrast, the lowest classification accuracy was achieved on 27 September during the autumn senescence period. This is potentially caused by high intraspecific variation in aspen autumn coloration but may also be related to our date of acquisition. Our findings indicate that multispectral drone images collected in spring can be used to locate and classify less frequent tree species highly accurately. The temporal variation in leaf and canopy appearance can alter the detection accuracy considerably.

• Hardenbol, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland https://orcid.org/0000-0002-0615-505X E-mail: alwin.hardenbol@uef.fi
• Kuzmin, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland; University of Eastern Finland, Department of Geographical and Historical Studies, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: anton.kuzmin@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
• Korpelainen, University of Eastern Finland, Department of Geographical and Historical Studies, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: pasi.korpelainen@uef.fi
• Kumpula, University of Eastern Finland, Department of Geographical and Historical Studies, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: timo.kumpula@uef.fi
• Maltamo, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: matti.maltamo@uef.fi
• Kouki, University of Eastern Finland, School of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: jari.kouki@uef.fi

Despite the importance of spectral properties of woody tree structures, they are seldom represented in research related to forests, remote sensing, and reflectance modeling. This study presents a novel imaging multiangular measurement set-up that utilizes a mobile handheld hyperspectral camera (Specim IQ, 400–1000 nm), and can measure stem bark spectra in a controlled laboratory setting. We measured multiangular reflectance spectra of silver birch (Betula pendula Roth), Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) stem bark, and demonstrated the potential of using bark spectra in identifying tree species using a Support Vector Machine (SVM) based approach. Intraspecific reflectance variability was the lowest in visible (400–700 nm), and the highest in near-infrared (700–1000 nm) wavelength regions. Interspecific variation was the largest in the red, red-edge and near-infrared spectral bands. Spatial variation of reflectance along the tree height and different sides of the stem (north and south) were found. Both birch and pine had increased reflectance in the forward-scattering directions for visible to near-infrared wavelength regions, whilst spruce displayed the same only for the visible wavelength region. In addition, spruce had increased reflectance in the backward-scattering directions. In spite of the intraspecific variations, SVM could identify tree species with 88.8% overall accuracy when using pixel-specific spectra, and with 97.2% overall accuracy when using mean spectra per image. Based on our results it is possible to identify common boreal tree species based on their stem bark spectra using images from mobile hyperspectral cameras.

• Juola, Aalto University, School of Engineering, Department of Built Environment, P.O. Box 14100, FI-00760 Aalto, Finland https://orcid.org/0000-0002-6050-7247 E-mail: jussi.juola@aalto.fi
• Hovi, Aalto University, School of Engineering, Department of Built Environment, P.O. Box 14100, FI-00760 Aalto, Finland https://orcid.org/0000-0002-4384-5279 E-mail: aarne.hovi@aalto.fi
• Rautiainen, Aalto University, School of Engineering, Department of Built Environment, P.O. Box 14100, FI-00760 Aalto, Finland; Aalto University, School of Electrical Engineering, Department of Electronics and Nanoengineering, P.O. Box 15500, FI-00760 Aalto, Finland https://orcid.org/0000-0002-6568-3258 E-mail: miina.a.rautiainen@aalto.fi

The stoniness index of forest soil describes the stone content in the upper soil layer at depths of 20–30 centimeters. This index is not available in any existing map databases, and traditional measurements for the stoniness of the soil have always necessitated laborious soil-penetration methods. Knowledge of the stone content of a forest site could be of use in a variety of forestry operations. This paper presents a novel approach to obtaining automatic measurements of soil stoniness during an excavator-based mounding operation. The excavator was equipped with only a low-cost inertial measurement unit and a satellite navigation receiver. Using the data from these sensors and manually conducted soil stoniness measurements, supervised machine learning methods were utilized to build a model that is capable of predicting the stoniness class of a given mounding location. This study compares different classifiers and feature selection methods to find the most promising solution for this learning problem. The discussion includes a proposition for a meaningful measurement resolution of the soil’s stoniness, and a practical method for evaluating the variability of the stone content of the soil. The results indicate that it is possible to predict the soil stoniness class with 70% accuracy using only the inertial and location measurements.

• Melander, Automation Technology and Mechanical Engineering, Tampere University, FI-33014 Tampere University, Finland http://orcid.org/0000-0003-3662-5187 E-mail: lari.melander@tuni.fi
• Ritala, Automation Technology and Mechanical Engineering, Tampere University, FI-33014 Tampere University, Finland http://orcid.org/0000-0003-0721-9948 E-mail: risto.ritala@tuni.fi
• Strandström, Metsäteho Oy, Vernissakatu 1, FI-01300 Vantaa, Finland E-mail: markus.strandstrom@metsateho.fi

Recent developments in on-board technology have enabled automatic collection of follow-up data on forwarder work. The objective of this study was to exploit this possibility to obtain highly representative information on time consumption of specific work elements (including overlapping crane work and driving), with one load as unit of observation, for large forwarders in final felling operations. The data used were collected by the John Deere TimberLink system as nine operators forwarded 8868 loads, in total, at sites in mid-Sweden. Load-sizes were not available. For the average and median extraction distances (219 and 174 m, respectively), Loading, Unloading, Driving empty, Driving loaded and Other time effective work (PM) accounted for ca. 45, 19, 8.5, 7.5 and 14% of total forwarding time consumption, respectively. The average and median total time consumptions were 45.8 and 42.1 minutes/load, respectively. The developed models explained large proportions of the variation of time consumption for the work elements Driving empty and Driving loaded, but minor proportions for the work elements Loading and Unloading. Based on the means, the crane was used during 74.8% of Loading PM time, the driving speed was nonzero during 31.9% of the Loading PM time, and Simultaneous crane work and driving occurred during 6.7% of the Loading PM time. Time consumption per load was more strongly associated with Loading drive distance than with extraction distance, indicating that the relevance of extraction distance as a main indicator of forwarding productivity should be re-considered.

• Manner, The Forestry Research Institute of Sweden (Skogforsk), Uppsala Science Park, SE-751 83 Uppsala, Sweden E-mail: jussi.manner@skogforsk.se
• Palmroth, John Deere Forestry, P.O. Box 472, FI-33101 Tampere, Finland E-mail: PalmrothLauri@JohnDeere.com
• Nordfjell, Swedish University of Agricultural Sciences, Department of Forest Biomaterials and Technology, SE-901 83 Umeå, Sweden E-mail: tomas.nordfjell@slu.se
• Lindroos, Swedish University of Agricultural Sciences, Department of Forest Biomaterials and Technology, SE-901 83 Umeå, Sweden E-mail: ola.lindroos@slu.se

• Abella, Department of Environmental and Occupational Health, University of Nevada Las Vegas, Las Vegas, Nevada 89154-3064 USA E-mail: scott.abella@unlv.edu

• Coggins, Department of Forest Resources Management, University of British Columbia, 2424 Main Mall, Vancouver, B.C., Canada V6T 1Z4 E-mail: scoggins@interchange.ubc.ca
• Coops, Department of Forest Resources Management, University of British Columbia, 2424 Main Mall, Vancouver, B.C., Canada V6T 1Z4 E-mail: ncc@nn.ca
• Wulder, Canadian Forest Service (Pacific Forestry Centre), Natural Resources Canada, 506 West Burnside Rd., Victoria, B.C., Canada V8Z 1M5 E-mail: maw@nn.ca

• Korpela, University of Helsinki, Dept of Forest Management, P.O. Box 27, FI-00014 University of Finland E-mail: ilkka.korpela@helsinki.fi
• Tuomola, University of Helsinki, Dept of Forest Management, P.O. Box 27, FI-00014 University of Finland E-mail: tt@nn.fi
• Tokola, University of Helsinki, Dept of Forest Management, P.O. Box 27, FI-00014 University of Finland E-mail: tt@nn.fi
• Dahlin, University of Helsinki, Dept of Forest Management, P.O. Box 27, FI-00014 University of Finland E-mail: bd@nn.fi

• 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

• Nieminen, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: mika.nieminen@metla.fi
• Penttilä, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: tp@nn.fi

• Hotanen, Finnish Forest Research Institute, Joensuu Research Centre, P.O.Box 68, FIN-80101 Joensuu, Finland E-mail: juha-pekka.hotanen@metla.fi

• Magnussen, Canadian Forest Service, 506 West Burnside Road, Victoria B.C., Canada V8Z 1M5 E-mail: smagnussen@pfc.forestry.ca
• Boudewyn, Canadian Forest Service, 506 West Burnside Road, Victoria B.C., Canada V8Z 1M5 E-mail: pb@nn.ca
• Wulder, Canadian Forest Service, 506 West Burnside Road, Victoria B.C., Canada V8Z 1M5 E-mail: mw@nn.ca
• Seemann, Canadian Forest Service, 506 West Burnside Road, Victoria B.C., Canada V8Z 1M5 E-mail: ds@nn.ca

• Wang, Department of Natural Resources and Environmental Sciences, University of Illinois, Urbana, IL, USA E-mail: wang12@staff2.cso.uiuc.edu
• Poso, Department of Forest Resource Management, P.O. Box 24, FIN-00014 University of Helsinki, Finland E-mail: sp@nn.fi
• Waite, Department of Forest Resource Management, P.O. Box 24, FIN-00014 University of Helsinki, Finland E-mail: mlw@nn.fi
• Holopainen, Department of Forest Resource Management, P.O. Box 24, FIN-00014 University of Helsinki, Finland E-mail: mh@nn.fi

• Zawadzki, Environmental Engineering Department, Warsaw Technical University, Ul. Nowowiejska 20, 00-653 Warsaw, Poland E-mail: jaroslaw.zawadzki@is.pw.edu.pl
• Cieszewski, D. B. Warnell School of Forest Resources, University of Georgia, Athens, GA 30602, USA E-mail: cjc@nn.us
• Zasada, Department of Forest Productivity, Faculty of Forestry, Warsaw Agricultural University, Poland E-mail: mz@nn.pl
• Lowe, D. B. Warnell School of Forest Resources, University of Georgia, Athens, GA 30602, USA E-mail: rcl@nn.us