Current issue: 54(2)
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.
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.
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.
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.
The article contains tree lectures given in the meeting of the Geographical Society in Finland on February 25th 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.
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.
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.
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.
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.
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
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.