Category :
Research article
article id 219,
category
Research article
Arto Haara,
Pekka Leskinen.
(2009).
The assessment of the uncertainty of updated stand-level inventory data.
Silva Fennica
vol.
43
no.
1
article id 219.
https://doi.org/10.14214/sf.219
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Predictions of growth and yield are essential in forest management planning. Growth predictions are usually obtained by applying complex simulation systems, whose accuracy is difficult to assess. Moreover, the computerised updating of old inventory data is increasing in the management of forest planning systems. A common characteristic of prediction models is that the uncertainties involved are usually not considered in the decision-making process. In this paper, two methods for assessing the uncertainty of updated forest inventory data were studied. The considered methods were (i) the models of observed errors and (ii) the k-nearest neighbour method. The derived assessments of uncertainty were compared with the empirical estimates of uncertainty. The practical utilisation of both methods was considered as well. The uncertainty assessments of updated stand-level inventory data using both methods were found to be feasible. The main advantages of the two studied methods include that bias as well as accuracy can be assessed.
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Haara,
University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland
E-mail:
arto.haara@joensuu.fi
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Leskinen,
Finnish Environment Institute, Research Programme for Production and Consumption, P.O. Box 111, FI-80101 Joensuu, Finland
E-mail:
pl@nn.fi
article id 238,
category
Research article
Mikko Kurttila,
Pekka Leskinen,
Jouni Pykäläinen,
Tiina Ruuskanen.
(2008).
Forest owners' decision support in voluntary biodiversity-protection projects.
Silva Fennica
vol.
42
no.
4
article id 238.
https://doi.org/10.14214/sf.238
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New forest-biodiversity-protection instruments based on temporary protection periods and non-industrial private forest owners’ voluntary participation have been recently introduced and tested in pilot areas located in Southern Finland. Thanks to their several benefits, the use of voluntary instruments is becoming more common in many other countries as well. Voluntary protection here means that forest owners voluntarily set aside tracts of forest to be protected and define their compensation fees. Depending on the objectives of the forest owners, the compensation fee reflects the forest owners’ (positive) attitude towards biodiversity, scenic beauty, recreational values and/or the existence of long-term cutting possibilities. When a forest owner decides to offer part of his/her forest holding to be temporarily protected, the owner faces a new decision problem related to definition of the compensation fee, which should be based on diverse information concerning stand- and holding-level opportunity costs as well as on the biodiversity value of the stand. This article introduces three decision-support elements for assisting forest owners in defining their compensation fees. The first element relates to the assessment of the potential stand-level loss of timber harvesting income that the temporary protection of the stand may cause. The second element sets the holding-level opportunity cost of protection by utilizing the forest owners’ holding level goals, the holdings’ production possibilities and optimization methods. The third element describes the biodiversity value of the stand by means of a multi-criteria expert model. Case study material collected from the area of Central Karelia Herb-rich Forests Network pilot project is used to illustrate the characteristics of the decision-support elements and to point out some development needs for the future use of these elements.
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Kurttila,
University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland
E-mail:
mikko.kurttila@joensuu.fi
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Leskinen,
Finnish Environment Institute, Research Programme for Production and Consumption, P.O. Box 111, FI-80101 Joensuu, Finland
E-mail:
pl@nn.fi
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Pykäläinen,
Metsämonex Ltd., Joensuu, Finland
E-mail:
jp@nn.fi
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Ruuskanen,
University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland
E-mail:
tr@nn.fi
article id 606,
category
Research article
Pekka Leskinen,
Jyrki Kangas.
(2001).
Modelling future timber price development by using expert judgments and time series analysis.
Silva Fennica
vol.
35
no.
1
article id 606.
https://doi.org/10.14214/sf.606
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Timber prices belong to the most important variables affecting the optimality of forest management. On the other hand, forecasting of timber prices is very uncertain. One difficulty when using past time series data in forecasting future timber price development is the possibility of changes in the markets and in the society at large. Expert knowledge can be applied in forecasting of timber prices as information additional to that provided by time series modelling. This paper presents an approach utilising both time series data and expert judgments in modelling future timber prices. A time series model is used as the basis for the approach. Parameters describing future timber price trends, variation in future timber prices, and the probabilities of price peaks taking place in the future are estimated with expert judgments as the basis. A case study involving 12 experts was carried out in Finland, and models were estimated for all the six major timber assortments in the country. The model produced can be utilised in the optimisation calculations of forest planning.
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Leskinen,
Finnish Forest Research Institute, Kannus Research Station, P.O. Box 44, FIN-69101 Kannus, Finland
E-mail:
pekka.leskinen@metla.fi
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Kangas,
Finnish Forest Research Institute, Kannus Research Station, P.O. Box 44, FIN-69101 Kannus, Finland
E-mail:
jk@nn.fi
article id 621,
category
Research article
Jyrki Kangas,
Pekka Leskinen,
Timo Pukkala.
(2000).
Integrating timber price scenario modeling with tactical management planning of private forestry at forest holding level.
Silva Fennica
vol.
34
no.
4
article id 621.
https://doi.org/10.14214/sf.621
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In forest management planning, deterministic timber prices are typically assumed. However, real-life timber prices vary in the course of time, and also price peaks, i.e. exceptionally high timber prices, might occur. If land-owners can utilise the price variation by selling timber with the high prices, they are able to increase their net revenues correspondingly. In this study, an approach is presented to study the timber price variation and its significance in the optimization of forest management. The approach utilizes stochastic timber price scenario modelling, simulation of forest development, and optimization of forest management. The approach is presented and illustrated by means of a case study. It is shown how the degree of uncertainty due to variation in timber prices can be analyzed in tactical forest planning of private forestry, and how the potential benefits of adaptive timber-selling behaviour for a forest landowner can be computed by using the approach. The effects of stochastic timber prices on the choice of forest plan are studied at the forest holding level considering also the spacing and type of cuttings and the optimal cutting order. A forest plan prepared under the assumption of constant timber price very seldom results in optimal forest management. Through studying the effects of stochastic timber prices, forest landowners and other decision makers obtain valuable information about the significance of adaptive timber selling behaviour. The presented methodology can also be used in analysing the land-owners’ economic risks as a function of time-price structure.
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Kangas,
Finnish Forest Research Institute, Kannus Research Station, P.O. Box 44, FIN-69101 Kannus, Finland
E-mail:
jyrki.kangas@metla.fi
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Leskinen,
Finnish Forest Research Institute, Kannus Research Station, P.O. Box 44, FIN-69101 Kannus, Finland
E-mail:
pl@nn.fi
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Pukkala,
University of Joensuu, Faculty of Forestry, P.O. Box 111, FIN-80101 Joensuu, Finland
E-mail:
tp@nn.fi
article id 677,
category
Research article
Pekka Leskinen,
Jyrki Kangas.
(1998).
Analysing uncertainties of interval judgment data in multiple-criteria evaluation of forest plans.
Silva Fennica
vol.
32
no.
4
article id 677.
https://doi.org/10.14214/sf.677
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The use of interval judgments instead of accurate pairwise comparisons has been proposed as a solution to facilitate the analysis of uncertainties in the widely applied pairwise comparisons technique. A method is presented for deriving probability distributions for the pairwise comparisons and for utilizing the distributions in the analysis of uncertainties in the evaluation process. The first step is that the expert or the decision-maker is queried as to the best guess of the priority ratio of the attributes compared. This is followed by an adjusting query concerning the uncertainty in the comparison: what is the probability of the priority ratio being between the best guess ± 1 unit of the pairwise comparison scale? An application of the method is presented in the form of multiple-criteria evaluation of alternative management plans for a forest area.
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Leskinen,
Finnish Forest Research Institute, Kannus Research Station, P.O. Box 44, FIN-69101 Kannus, Finland
E-mail:
pekka.leskinen@metla.fi
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Kangas,
Finnish Forest Research Institute, Kannus Research Station, P.O. Box 44, FIN-69101 Kannus, Finland
E-mail:
jk@nn.fi