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Now showing items 316-335 of 668
  • Ilvessalo, Yrjö (Suomen metsätieteellinen seura, 1954)
  • Laitakari, Erkki (Suomen metsätieteellinen seura, 1934)
  • Yli-Vakkuri, Paavo (Suomen metsätieteellinen seura, 1954)
  • Hertz, Martti (Suomen metsätieteellinen seura, 1925)
  • Pesonen, Mauno; Kettunen, Arto; Räsänen, Petri (The Society of Forestry in Finland - The Finnish Forest Research Institute, 1995)
    The factors affecting the non-industrial, private forest landowners' (hereafter referred to using the acronym NIPF) strategic decisions in management planning are studied. A genetic algorithm is used to induce a set of rules predicting potential cut of the landowners' choices of preferred timber management strategies. The rules are based on variables describing the characteristics of the landowners and their forest holdings. The predictive ability of a genetic algorithm is compared to linear regression analysis using identical data sets. The data are cross-validated seven times applying both genetic algorithm and regression analyses in order to examine the data-sensitivity and robustness of the generated models. The optimal rule set derived from genetic algorithm analyses included the following variables: mean initial volume, landowner's positive price expectations for the next eight years, landowner being classified as farmer, and preference for the recreational use of forest property. When tested with previously unseen test data, the optimal rule set resulted in a relative root mean square error of 0.40. In the regression analyses, the optimal regression equation consisted of the following variables: mean initial volume, proportion of forestry income, intention to cut extensively in future, and positive price expectations for the next two years. The R2 of the optimal regression equation was 0.34 and the relative root mean square error obtained from the test data was 0.38. In both models, mean initial volume and positive stumpage price expectations were entered as significant predictors of potential cut of preferred timber management strategy. When tested with the complete data set of 201 observations, both the optimal rule set and the optimal regression model achieved the same level of accuracy.
  • Pesonen, Mauno (The Society of Forestry in Finland - The Finnish Forest Research Institute, 1995)
    In the study, the potential allowable cut in the district of Pohjois-Savo - based on the non-industrial private forest landowners' (NIPF) choices of timber management strategies - was clarified. Alternative timber management strategies were generated, and the choices and factors affecting the choices of timber management strategies by NIPF landowners were studied. The choices of timber management strategies were solved by maximizing the utility functions of the NIPF landowners. The parameters of the utility functions were estimated using the Analytic Hierarchy Process (AHP). The level of the potential allowable cut was compared to the cutting budgets based on the 7th and 8th National Forest Inventories (NFI7 and NFI8), to the combining of private forestry plans, and to the realized drain from non-industrial private forests. The potential allowable cut was calculated using the same MELA system as has been used in the calculation of the national cutting budget. The data consisted of the NIPF holdings (from the TASO planning system) that had been inventoried compartmentwise and had forestry plans made during the years 1984-1992. The NIPF landowners' choices of timber management strategies were clarified by a two-phase mail inquiry. The most preferred strategy obtained was "sustainability" (chosen by 62 % of landowners). The second in order of preference was "finance" (17 %) and the third was "saving" (11 %). "No cuttings", and "maximum cuttings" were the least preferred (9 % and 1 %, resp.). The factors promoting the choices of strategies with intensive cuttings were a) "farmer as forest owner" and "owning fields", b) "increase in the size of the forest holding", c) agriculture and forestry orientation in production, d) "decreasing short term stumpage earning expectations", e) "increasing intensity of future cuttings", and f) "choice of forest taxation system based on site productivity". The potential allowable cut defined in the study was 20 % higher than the average of the realized drain during the years 1988-1993, which in turn, was at the same level as the cutting budget based on the combining of forestry plans in eastern Finland. Respectively, the potential allowable cut defined in the study was 12 % lower than the NFI8-based greatest sustained allowable cut for the 1990s. Using the method presented in this study, timber management strategies can be clarified for non-industrial private forest landowners in different parts of Finland. Based on the choices of timber managemet strategies, regular cutting budgets can be calculated more realistically than before.
  • Schager, Nils (Suomen metsätieteellinen seura, 1929)
  • Turakka, Antti; Luukkanen, Olavi; Bhumibhamon, Suree (Suomen metsätieteellinen seura, 1982)
  • Ilvessalo, Yrjö (Suomen metsätieteellinen seura, 1929)
  • Laitakari, Erkki (Suomen metsätieteellinen seura, 1954)
  • Ristimäki, Toini (Suomen metsätieteellinen seura, 1955)
  • Päivänen, Juhani (Suomen metsätieteellinen seura, 1974)
  • Keltikangas, Valter (Suomen metsätieteellinen seura, 1945)
  • Heikurainen, Leo; Seppälä, Kustaa (Suomen metsätieteellinen seura, 1973)
  • Appelroth, Eric (Suomen metsätieteellinen seura, 1942)
  • Backman, A. L. (Suomen metsätieteellinen seura, 1934)
  • 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.
  • 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.
  • Osmaston, A. E. (Suomen metsätieteellinen seura, 1929)