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High productivity in forest harvesting requires efficient forwarding. Planning is complicated by multiple choices of routes and their order, the number and types of assortments, the loading sequence, and pile organization at the landing. This paper develops and tests a decision support tool for forwarder routing with sequential co-loading of assortments. Input data are the harvester production file (including Global Navigation Satellite Systems tracking), placement of landing, and machine specifications. The trail network is generated from the harvester production data when devising routes to pick up all log piles, including specific assortments and volumes. Multiple assortments can be loaded along each route, and a certain loading sequence of assortments is preferred and (or) required. Sorting time during co-loading varies, depending on the assortment combinations and bunk loading pattern. Route planning is modeled using a set-partitioning problem, and the solution method is a metaheuristic based on repeated matching. In addition to routes and loading sequences, solutions include the organization of assortment piles at the landing, depending on the total volume of each assortment. The tool produces similar results to those attained by skilled forwarder operators on five clearcuts (3–11 ha) in northern Sweden, when the results are compared with data from actual forwarder production files. [ABSTRACT FROM AUTHOR]

In recent years, increasing attention has been drawn to improving productivity in logging passages while reducing negative impact on soil and water. The position of landings and extraction routes is crucial in these efforts, as it has a huge impact on efficient and sustainable forwarder passages. In this paper, we propose a two-phase approach to identify the best possible landing locations integrated with log extraction route design. The first phase identifies potential landing zones adjacent to forest roads. It considers practical restrictions such as slopes, stoniness, and closeness to infrastructure. The second phase uses an optimization model to evaluate the potential impact of each zone and aggregate zones, selecting one or two complete landings. This model is a relaxation of a formulation for an extraction route design; it is used to minimize a weighted objective of the total driving distance, avoid steep terrains and impact on soil and water. The proposed approach has been tested on a set of harvest areas in southern Sweden. The results not only show the potential to identify feasible landing zones but also identify a shorter driving distance and hence lower contractual cost with optimized positioning. The possibility to increase efficiency in forest operations by performing scenario analysis and thus forwarding distances with different landing sites is among the results. [ABSTRACT FROM AUTHOR]

In forest management planning, the dynamic treatment unit (DTU) approach has become an increasingly relevant alternative to the traditional planning approach using fixed stands, due to improved remote sensing techniques and optimization procedures, with the potential for the higher goal fulfillment of forest activities. For the DTU approach, the traditional concept of fixed stands is disregarded, and forest data are kept in units with a high spatial resolution. Forest operations are planned by clustering cells to form treatment units for harvest operations. This paper presents a new model with an exact optimization technique for forming DTUs in forest planning. In comparison with most previous models, this model aims for increased flexibility by modelling the spatial dimension according to cell proximity rather than immediate adjacency. The model is evaluated using a case study with harvest flow constraints for a forest estate in southern Sweden, represented by 3587 cells. The parameter settings differed between cases, resulting in varying degrees of clustered DTUs, which caused relative net present value losses of up to 4.3%. The case without clustering had the lowest net present value when considering entry costs. The solution times varied between 2.2 s and 42 min 6 s and grew rapidly with increasing problem size. [ABSTRACT FROM AUTHOR]

This paper describes the development and implementation of a model to measure and compare transaction costs in situations of multiple land use, where interdependence prevails between the agents — thus actions of one agent affects others. Transaction costs typically occur in situations where limited resources are used by more than one agent and bargaining of the use is conducted to mitigate conflict. The model of the paper is empirically tested on one such situation: forestry and reindeer husbandry, which is pursued in northern Sweden where transaction costs occur in common land use as a result of consultations. The results indicate that transaction costs are unevenly distributed between the two agents, where reindeer husbandry carries the highest costs, resulting in uneven power relations. Transaction costs are driven by the presence of Land Use Plans of reindeer husbandry, interestingly enough driving the costs in different directions for the two agents. The model illustrates the elements of transaction costs in a common pool resource situation, and the results are not only useful for this specific situation in policymaking, but also for other similar situations. [ABSTRACT FROM AUTHOR]

Cross-dating is considered one of the most important principles of dendrochronology. The first known cross-dating attempts, conducted between the years 1737 and 1783 by independent researchers in France, Germany, and Sweden, were related to the identification of growth rings believed to have formed during the harsh winter of 1708–1709. In this paper, we present a novel perspective on the birth of dendrochronology and cross-dating in the 1700s. We focus on the ideas and experimental studies of one of the lesser known pioneers, Johan Leche (1704–1764), the Professor of Medicine at the Royal Academy (Turku, Finland). Instead of winter harshness, Leche was fascinated by the drought that killed and damaged several trees and tree species in the summer of 1757. Leche conducted several dendrochronological and field experiments described only in his unpublished manuscript filed in the National Archives in Sweden. Reviewing Leche's measurements of ring-width series of multiple radii and his comparisons between the radii, it seems only fair to include him in the long list of natural historians who made important contributions to the field of dendrochronology. His manuscript was never published, which is why Leche's dendrochronological experiments and recommendations never reached a wider audience. [ABSTRACT FROM AUTHOR]

A number of national environmental objectives have been decided on by the Swedish parliament. In this paper, a measure of willingness to pay for attaining these objectives is outlined in terms of an “environmental budget”, which can be disaggregated. Based on a nationwide contingent valuation survey, the average environmental budget was estimated and then disaggregated on specific “green” indicators. This paper focuses especially on protection of forest land for biodiversity purposes. Multiple bounded dichotomous choice questions were employed in the survey, allowing respondents to express uncertainty in their valuations. The effect of different question formats and valuation scenarios on the disaggregation of the environmental budget was investigated. Consideration of uncertainty had a significant impact on willingness to pay estimates. Willingness to pay varied between different levels of forest land protection when uncertainty was explicitly introduced. When valuation estimates were aggregated on the national level, the value of forest land protection exceeded the costs by a small margin. Plusieurs objectifs environnementaux ont été arrêtés par le Parlement suédois pour l’ensemble du pays. La mesure du consentement à payer pour atteindre ces objectifs constitue l’objet de cet article. Cette mesure est présentée en terme de budget environnemental qui peut être décomposé. tabli à partir d’un sondage réalisé avec la méthode d’évaluation contingente à l’échelle du pays, le budget environnemental moyen a été estimé puis décomposé selon des indicateurs « verts »spécifiques. Cet article met une emphase particulière sur la protection du territoire forestier pour des fins de biodiversité. Des questions contraintes par des choix de réponses multiples dichotomiques ont été utilisées lors du sondage pour permettre aux répondants d’exprimer de l’incertitude à propos de leurs évaluations. L’effet des différentes formulations des questions et des différents scénarios d’évaluation proposés sur la décomposition du budget environnemental a été étudié. Le fait de considérer l’incertitude a un impact significatif sur les estimations du consentement à payer. Le consentement à payer varie selon le niveau de protection du territoire forestier lorsque l’incertitude est explicitement introduite. Lorsque les estimations des valeurs sont regroupées à l’échelle nationale, la valeur de la protection du territoire forestier excède légèrement les coûts. [ABSTRACT FROM AUTHOR]

Promotion of renewable energy sources in Europe is foreseen to result in a dramatic increase in the demand for woody biomass. This paper assesses whether wood resources in the European Union (EU) will support future demand. Possible implications for countries with ample forest resources and a well-developed forest industry, such as Sweden, of an expected mounting demand pressure are discussed. Other drivers of change in global wood product markets posing challenges for the forest sector in general are also addressed. These drivers are reviewed and, together with the results from the EUwood project and econometric wood market models, analyzed as to their impacts on the Swedish forest sector. Demand is foreseen to vastly exceed the potential supply of woody biomass in Europe, putting a tremendous pressure on the Swedish forest resource and necessitating trade-offs between different ecosystem services. Further, projections suggest that Sweden will decrease in importance in production as well as consumption terms for all wood products. [ABSTRACT FROM AUTHOR]