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Veikko Hiltunen Mikko Kurttila Pekka Leskinen Karri Pasanen Jouni Pykäläinen 《Forest Policy and Economics》2009,11(1):1-9
We tested the Mesta Internet-based decision-support application in connection with a natural resources planning (NRP) process in Eastern and Western Lapland, Finland. The aim in this process was to define the land-use allocation and the corresponding forest management operations for state-owned forests within these planning regions. Mesta was used in examining and evaluating the strategy alternatives from the viewpoint of the stakeholders' objectives. The basic idea in using Mesta is to define the acceptance thresholds that divide the alternatives into ‘acceptable’ and ‘not acceptable’ alternatives with respect to each decision criterion. The thresholds are adjusted holistically, i.e. so that all decision criteria and criteria values of all decision alternatives are simultaneously visible from the user interface. The holistic adjustment process is continued until an acceptable solution compliant with the production possibilities of the planning area is found. In the NRP process, the members of the stakeholder group first used Mesta individually to set their own thresholds. Next, the participants' acceptance thresholds were combined and a negotiation process was launched to find the group's common acceptance thresholds. This negotiation was also supported by Mesta. The result of the negotiation was that the participants were able to collaboratively decide on their recommendation for the future land-use allocation and the forest management principles to be applied in the two planning regions. The main benefit of Mesta as a decision-support tool during the negotiation process of the group was that the participants were forced to merge their preferences with the realistic production possibilities of the planning regions. 相似文献
73.
Erkki Mäntymaa Artti Juutinen Mikko Mönkkönen Rauli Svento 《Forest Policy and Economics》2009,11(7):498-507
A new market-based voluntary programme aimed at preserving forest habitats on private land has been implemented in Finland. This scheme is based on conservation by fixed-term agreements between forest owners and a governmental authority. In this study we examine the characteristics of forest owners and their properties that indicate the owners' willingness to participate in the programme. In addition, we analyse factors affecting the real compensation claims. The study uses a dual set of data from the pilot project, i.e. one data set supplied by the authority and another collected from the owners involved in the project. The results suggest that to increase the participation rate, information on the conservation project should be targeted in particular to the forest owners who either emphasize financial investment as a motive for forest ownership, have positive attitudes toward nature protection, or own large amounts of forest property. Additionally, owners' positive environmental preferences would decrease and high harvesting value and high ecological quality of a preserved forest stand would increase compensation claims. The voluntary programme could not, however, circumvent owners' strategic behaviour with respect to the claims. 相似文献
74.
Mikko Kurttila Eero Muinonen Pekka Leskinen Harri Kilpeläinen Jouni Pykäläinen 《European Journal of Forest Research》2009,128(1):37-50
A proper forest planning process includes the assessment of the decision-makers’ preferences concerning the future forest
use. For some owners, it may be a difficult task to express their preferences exactly and in the form that is required for
planning calculations. This study presents a new kind of approach for analyzing the effects of preferential uncertainty. The
approach consists of examination of the differences in the actual decision variables in forest planning, i.e. selected treatments
for stands between holding-level forest plans. In example calculations, the preferential uncertainty was examined from three
different viewpoints: the uncertainty in the weights of the objective variables; the uncertainty in the partial utility function;
and the combination of these two uncertainty sources. One thousand preference realizations were generated for each of these
uncertainty sources. More than one treatment schedules are proposed for stands that are affected by preferential uncertainty.
These stands were detected from among the resulting set of 1,000 forest plans. With this done, two potential decision-making
strategies, an adaptive behavior strategy and a threshold proportion strategy, were applied as guides in decision-making for
stands, which have more than one treatment alternative selected in the produced optimal forest plans. The adaptive behavior
technique required that the forest owner select one treatment alternative for at least one stand that has more than one proposed
treatment alternative. The treatment alternatives having frequencies exceeding the given threshold frequency were all accepted
simultaneously in the threshold strategy. The main benefit of the approach is to present the effects of uncertainties in a
way that can be easily understood by the actual decision-makers. It is a promising tool for practical decision-making situations
because at least Finnish non-industrial private forest owners quite often focus on making stand-level forest management decisions.
It is also suitable for examinations of other uncertainty sources such as timber prices or inventory data. 相似文献
75.
Voluntary biodiversity protection tools have been adopted for practical use in many countries where non-industrial private
forest ownership includes invaluable biodiversity resources. This has created a new kind of decision problem for individual
forest owners: they should be able to define their conditions for entering into a biodiversity protection contract including
sometimes a predetermined subsidy. This study presents a holding-level method for examining this decision problem. The method
is based on utilization of interactive optimization where the possible subsidy has been included in the protection (no treatment)
alternative of the examined stand. Generally, interactive optimization means that the landowner pinpoints the best plan by
interactively studying and learning the production possibilities of his/her forest holding. Following changes made to the
objective function by the forest owner, new solutions are presented for forest owners’ evaluation. If the “No treatments”
option is selected in optimization for these areas, the forest owner would benefit more—in the current location of the production
frontier and with the current subsidy—from entering into the protection contract than from cutting the specific forest area.
In the case study, we demonstrate that the values of the holding-level goals, production possibilities of the planning area
and the levels of the subsidy have a significant effect on the optimal decisions relating to biodiversity protection on the
stand level. 相似文献
76.
Ville Hallikainen Hannu Hökkä Mikko Hyppönen Pasi Rautio 《Scandinavian Journal of Forest Research》2019,34(2):115-125
The objective of the study was to examine the success of regeneration in gaps of variable size in pine-dominated stands in terms of seedling density. It was based on an experiment in central Lapland containing circular clear-cut gaps of 20, 40 and 80 m in diameter on typical sub-xeric and xeric pine sites with site preparation (patch scarification). The observation period covered the first five years after cutting. The average number of seedlings that had emerged after gap cutting was about 22 000?ha?1 for pine and 7 000?ha?1 for birch. The proportion of regeneration sample plots without any pine seedlings was less than 10%. The seedling density diminished constantly with greater distance from the edge stand but indicating sufficient density up to the largest gap size in the study (diameter 80 m, area ca. 0.5?ha). Site preparation promoted regeneration remarkably, and we conclude that successful regeneration would be achieved in most cases with soil scarification exposing just 10–20% of the soil surface. 相似文献
77.
Wardill TJ List O Li X Dongre S McCulloch M Ting CY O'Kane CJ Tang S Lee CH Hardie RC Juusola M 《Science (New York, N.Y.)》2012,336(6083):925-931
Color and motion information are thought to be channeled through separate neural pathways, but it remains unclear whether and how these pathways interact to improve motion perception. In insects, such as Drosophila, it has long been believed that motion information is fed exclusively by one spectral class of photoreceptor, so-called R1 to R6 cells; whereas R7 and R8 photoreceptors, which exist in multiple spectral classes, subserve color vision. Here, we report that R7 and R8 also contribute to the motion pathway. By using electrophysiological, optical, and behavioral assays, we found that R7/R8 information converge with and shape the motion pathway output, explaining flies' broadly tuned optomotor behavior by its composite responses. Our results demonstrate that inputs from photoreceptors of different spectral sensitivities improve motion discrimination, increasing robustness of perception. 相似文献
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Leaf properties vary significantly within plant canopies, due to the strong gradient in light availability through the canopy, and the need for plants to use resources efficiently. At high light, photosynthesis is maximized when leaves have a high nitrogen content and water supply, whereas at low light leaves have a lower requirement for both nitrogen and water. Studies of the distribution of leaf nitrogen (N) within canopies have shown that, if water supply is ignored, the optimal distribution is that where N is proportional to light, but that the gradient of N in real canopies is shallower than the optimal distribution. We extend this work by considering the optimal co-allocation of nitrogen and water supply within plant canopies. We developed a simple 'toy' two-leaf canopy model and optimized the distribution of N and hydraulic conductance (K) between the two leaves. We asked whether hydraulic constraints to water supply can explain shallow N gradients in canopies. We found that the optimal N distribution within plant canopies is proportional to the light distribution only if hydraulic conductance, K, is also optimally distributed. The optimal distribution of K is that where K and N are both proportional to incident light, such that optimal K is highest to the upper canopy. If the plant is constrained in its ability to construct higher K to sun-exposed leaves, the optimal N distribution does not follow the gradient in light within canopies, but instead follows a shallower gradient. We therefore hypothesize that measured deviations from the predicted optimal distribution of N could be explained by constraints on the distribution of K within canopies. Further empirical research is required on the extent to which plants can construct optimal K distributions, and whether shallow within-canopy N distributions can be explained by sub-optimal K distributions. 相似文献
80.
Kaisa J. Raatikainen Anna Oldén Niina Käyhkö Mikko Mönkkönen Panu Halme 《Landscape Ecology》2018,33(12):2169-2187