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  • Leinonen, Kari; Leikola, Matti; Peltonen, Antti; Räsä­nen, Pentti K. (The Society of Forestry in Finland - The Finnish Forest Research Institute, 1989)
  • Selby, J. Ashley (The Society of Forestry in Finland - The Finnish Forest Research Institute, 1989)
    A theoretical and philosophical examination of the ways in which behaviour of entrepreneurs relates to the business environment, with an empirical case study of the business attitudes, perceived business environments and ability to use business-related information of small sawmill entrepreneurs.
  • Atipanumpai, Ladawan (The Society of Forestry in Finland - The Finnish Forest Research Institute, 1989)
    Results are reported from studies on variation in growth characteristics, foliar nutrient concentration, phyllode anatomy and stomatal frequency of 16 different sources in a provenance trial in Thailand. Family variation and heritability of growth and flowering frequency were calculated for 20 open-pollinated families at the age of 28 months. In laboratory studies, transpiration rate, leaf conductance and leaf water potential were measured for different soil moisture regimes. Responses of photosynthesis, photorespiration and dark respiration, and CO2 compensation point were assessed in relation to temperature and irradiance. Recommendations are made for the selection of A. mangium provenances for planting in Thailand.
  • Hakkila, Pentti (The Society of Forestry in Finland - The Finnish Forest Research Institute, 1989)
    A review of logging in Finland in relation to new logging technology developed in Nordic countries to meet their own specific requirements and constraints (high salaries, costs of social security, strict ergonomic standards, specific logging conditions, predominance of private ownership, and strong environmental and conservation concerns). Logging technology is based typically on the log-length method and load-carrying forwarders.
  • Finér, Leena (The Society of Forestry in Finland - The Finnish Forest Research Institute, 1989)
    Biomass, biomass increment and nutrient cycling were studied in (1) a Scots pine (Pinus sylvestris) stand, (2) a Norway spruce (Picea abies) stand and (3) a mixed birch (Betula pubescens)/pine stand on a drained mire at Ilomantsi, eastern Finland in 1979-85. In addition, the effect of NPK and micronutrient fertilizer treatment was studied. Above-ground and root measurements were taken. These data formed the basis of stand biomass and nutrient cycle simulations of fertilized and unfertilized stands. The increases in biomass were greater in (1) and (2) in the fertilized simulation than in the unfertilized one. For (3), the effect of fertilization on biomass increment was small. In six years only part of the applied fertilizer had been fixed in the biomass of the model stands and proportionally less micronutrients than macronutrients. The potassium stores were small compared to the nutrient amounts fixed by the stands. This supports the notion that there is a shortage of potassium on deep-peat soils.
  • Lahtinen, Aatos (Suomen metsätieteellinen seura, 1988)
    A standard tree tapers off monotonically upwards. An algorithm is presented for constructing a monotony preserving taper curve using a quadratic spline. It is suggested that the resultant taper curve is better than the usual cubic spline.
  • Korpilahti, Eeva (Suomen metsätieteellinen seura, 1988)
    Data were collected over 3 yr during the growing season in a 20-yr-old stand at the Forestry Field Station of the University of Helsinki, Finland, to study the relations of photosynthesis and transpiration to environmental factors (irradiance, temperature, water content of soil and air) and metabolic processes.
  • Omwami, Raymond K. (Suomen metsätieteellinen seura, 1988)
    A study aimed at applying concepts of economic theory relevant to the formulation of a long-term timber production model as a basis of forest policy. A vertically integrated forest sector production model is described, together with its application in a developing economy and the derivation of a dynamic silvicultural investment criterion (in a labour surplus economy).
  • Nygren, Markku (Suomen metsätieteellinen seura, 1987)
    Tests on seeds from a natural stand and from a clone archive, with various photoperiods and temperature regimes, showed that germination was delayed at low temperature (10 degrees C) and in darkness. This effect diminished the later in autumn seeds were collected.
  • Peng, Shikui (Suomen metsätieteellinen seura, 1987)
    A study of a 194.3 ha area of forest land dominated by Norway spruce and Scots pine in central S. Finland. A general procedure is presented and discussed for integrating data from permanent sample plots and from satellite images for continuous forest inventory of large areas and for compartment estimations. Methods for estimation, updating and statistical analysis are examined.
  • Westman, Carl Johan (Suomen metsätieteellinen seura, 1987)
    Results are presented from a study of growth increases resulting from a factorial NPK fertilizer experiment in NE Finland. Data were collected for 2624 sample trees (mainly Scots pine, with some Norway spruce and Betula pubescens) on 164 sample plots at 19 sites. Five edaphic groups were distinguished for the sample plots based on N-P and acid-base gradients. In general, stand volume of the sites was low (5-70 msuperscript 3/ha) and overall stand response to drainage and fertilizers was small, especially on the less fertile sites, although individual trees showed strong responses.
  • Leikola, Matti (Suomen metsätieteellinen seura, 1987)
    For 1912-84, some 131 theses were published in forestry sciences, mainly in Finnish (75%), and averaged 151 pages in length. Of graduating foresters, 2-6% (av. of recent years 5.5%) presented doctoral dissertations at an av. age of 36.6 yr, mostly (37%) as part of their employment.
  • Keltikangas, Matti; Laine, Jukka; Puttonen, Pasi; Seppälä, Kustaa (Suomen metsätieteellinen seura, 1986)
    Data are presented from 1312 km of inventory transect, 6030 relascope sample plots and 21 700 ditches. Of the Finnish peatlands studied, more than 60% were pine mires, almost 20% were spruce mires and less than 10% each were treeless mires and paludified upland forest sites. The survey included the condition of the drainage networks, and the post-drainage development of the tree stands, their structure and silvicultural condition.
  • Luomajoki, Alpo (Suomen metsätieteellinen seura, 1986)
    A study of 16 tree species showed that, including yearly and latitudinal variation, the tetrad phase was reached from late March to early June in conifers and Populus tremula (correlated with heat sums) and in late July to mid-Aug. in Betulaceae (correlated with daylength). These differences were thought to be associated with seasonal adaptive strategies rather than taxonomic relationships.
  • Huhta, Veikko; Hyvönen, Riitta; Koskenniemi, Antti; Vilkamaa, Pekka; Kaasalainen, Paula; Sulander, Minna (Suomen metsätieteellinen seura, 1986)
  • Oker-Blom, Pauline (Suomen metsätieteellinen seura, 1986)
    In modeling canopy structure, a statistical approach is applied to assign the location and orientation of plant parts; the radiation field is described in terms of random variables and their distributions. A comparison of horizontally homogeneous stands and grouped forest stands showed that grouping reduced interception of radiation and increased spatial variation. In conifers, the grouping of needles into shoots and the effect of penumbra had an important influence on the distribution of radiation on the needle area.
  • Vehkamäki, Seppo (Suomen metsätieteellinen seura, 1986)
    Using a macromodel of a closed economy in which gross national product is assumed to be linearly dependent on the supply of raw wood, marginal conditions are derived for optimum equilibrium forestry with respect to growing stock and silviculture. The effects on Finnish forest owners' behaviour of various forms of taxation and subsidies, and investment are examined. Empirical studies are included concerning the raw wood market for softwood logs and silvicultural investments for tending young stands.
  • Silvola, Jouko; Välijoki, Jukka; Aaltonen, Heikki (Suomen metsätieteellinen seura, 1985)
    At sites in SE Finland, hourly respiration varied mainly in the range 100-500 mg CO2/msuperscript 2 with changes following those in soil surface temp. with a time lag of 3 h. After groundwater table was reduced by about 0.5 m, respiration increased 2.5-fold (resulting in a rate of peat decomposition considerably in excess of the rate of production of new organic matter in the peat). Application of fast-dissolving PK or urea rapidly increased soil respiration at the site poorest in nutrients. Ash gave the greatest steady increase. At sites rich in nutrients, fertilizer treatment reduced soil respiration for 1-2 yr. Treatment with micronutrients caused an intial reduction in respiration followed by a pronounced increase.
  • Kuusipalo, Jussi (Suomen metsätieteellinen seura, 1985)
    The vegetation and some physical and chemical soil properties were studied in 410 sample plots in a random sample of stands by two-way indicator species analysis, discriminant analysis and analysis of variance. Understorey vegetation was dependent on site fertility and on the tree stand (especially species composition). Although the forest vegetation was distributed in a rather continuous way along a soil fertility gradient, relatively unambiguous site classification was possible based on the appearance of indicator species and species groups.
  • Smolander, Heikki (Suomen metsätieteellinen seura, 1984)
    Measurements were made of temporal and spatial microvariations in irradiance in a small part of the canopy of a 20-yr-old Scots pine stand. Linear integration of the variations gave biased estimates; second order Taylor series approximations were satisfactory only for a low curvature response; two-point distribution approximations were applicable to high and low curvature response but presupposed that the mean and variance were known. It is suggested that a light measuring method in which first power (mean) and second power (variance) of irradiance are integrated resolves these problems; the method takes into account the geometry of the shoot and can also be used in transpiration studies.