79 research outputs found

    Planning under risk and uncertainty

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    This thesis concentrates on the optimization of large-scale management policies under conditions of risk and uncertainty. In paper I, we address the problem of solving large-scale spatial and temporal natural resource management problems. To model these types of problems, the framework of graph-based Markov decision processes (GMDPs) can be used. Two algorithms for computation of high-quality management policies are presented: the first is based on approximate linear programming (ALP) and the second is based on mean-field approximation and approximate policy iteration (MF-API). The applicability and efficiency of the algorithms were demonstrated by their ability to compute near-optimal management policies for two large-scale management problems. It was concluded that the two algorithms compute policies of similar quality. However, the MF-API algorithm should be used when both the policy and the expected value of the computed policy are required, while the ALP algorithm may be preferred when only the policy is required. In paper II, a number of reinforcement learning algorithms are presented that can be used to compute management policies for GMDPs when the transition function can only be simulated because its explicit formulation is unknown. Studies of the efficiency of the algorithms for three management problems led us to conclude that some of these algorithms were able to compute near-optimal management policies. In paper III, we used the GMDP framework to optimize long-term forestry management policies under stochastic wind-damage events. The model was demonstrated by a case study of an estate consisting of 1,200 ha of forest land, divided into 623 stands. We concluded that managing the estate according to the risk of wind damage increased the expected net present value (NPV) of the whole estate only slightly, less than 2%, under different wind-risk assumptions. Most of the stands were managed in the same manner as when the risk of wind damage was not considered. However, the analysis rests on properties of the model that need to be refined before definite conclusions can be drawn

    Importance of bioenergy markets for the development of the global energy system

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    International audienceFossil fuels such as oil, coal and gas dominate the global energy supply, covering more than 80% of the total primary energy supply of 508 EJ in 2009. In order to reach climate targets and create low-carbon economies, biomass is expected to play a pivotal role. While the future resource potential of biomass may be significant and the global trade of bioenergy is rapidly expanding, biomass is currently only playing a minor role in the global energy supply. Total biomass primary energy supply was 51 EJ in 2008, of which more than 60% constituted for traditional use such as cooking and heating in developing countries (India and sub-Saharan Africa). The main applications of modern use of biomass are today firstly, in the industrial sector to produce process steam, and secondly, in the power sector

    Industrial and Environmental Impacts of an Expanding Bio-Energy Sector

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    Available on: http://www.iiis.org/CDs2011/CD2011SCI/EEEP_2011/PapersPdf/JA919AE.pdfInternational audienceIn the context of mitigating climate change and increasing energy security, the use of bio-energy production is expected to play a major role. However, an increased use of woody biomass sources for bio-energy production has in Sweden induced pressure on the woody biomass sources available and influenced forestry management. In this paper we analyze the competition of biomass sources and changes in management of woody resources induced by the joint expansion of the bioenergy sector and forest industries. Results show that increased demand of biomass sources may induce a short-term increase of forest harvesting. However, in the long-term, adequate biomass sources was found to be available to fulfill the joint demand of biomass sources for the production of bioenergy and woody produc

    Sub-national TIMES model for analyzing regional future use of Biomass and Biofuels in France and Sweden

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    International Energy Workshop : http://www.kth.se/polopoly_fs/1.64178!Paper_B4_Forsell.pdfInternational audienceIn the context of mitigating climate change and increase energy security, the utilization of biomass in the energy sector is expected to play a major role. However, to estimate the possibility of fulfilling national goals concerning the future use of biomass sources and to estimate the future use of biomass sources in the energy sector, the current energy system models needs to be further developed to consider the high sub-national variances in the supply and cost of the biomass sources. In this paper we present a sub-national MARKAL/TIMES model for estimating regional utilization of biomass sources and the future development of the energy system. The proposed model is evaluated for two case studies, France and Sweden, for which the future utilization of biomass is evaluated utilizing numerous scenarios of the potential supply of biomass, cost of biomass, and end-use demand. Our results show that the limit of national biomass potentials for energy purposes in France is approximately 35 Mtoe, while all demand scenarios for Sweden could be fulfilled by national biomass potentials. Furthermore, the results show that there are large differences in the regional utilization level of biomass sources, even when the total utilization level of biomass sources is high

    Combining Climate Change Mitigation Scenarios with Current Forest Owner Behavior: A Scenario Study from a Region in Southern Sweden

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    This study investigates the need for change of current forest management approaches in a southern Swedish region within the context of future climate change mitigation through empirically derived projections, rather than forest management according to silvicultural guidelines. Scenarios indicate that climate change mitigation will increase global wood demand. This might call for adjustments of well-established management approaches. This study investigates to what extent increasing wood demands in three climate change mitigation scenarios can be satisfied with current forest management approaches of different intensities in a southern Swedish region. Forest management practices in Kronoberg County were mapped through interviews, statistics, and desk research and were translated into five different management strategies with different intensities regulating management at the property level. The consequences of current practices, as well as their intensification, were analyzed with the Heureka Planwise forest planning system in combination with a specially developed forest owner decision simulator. Projections were done over a 100-year period under three climate change mitigation scenarios developed with the Global Biosphere Management Model (GLOBIUM). Current management practices could meet scenario demands during the first 20 years. This was followed by a shortage of wood during two periods in all scenarios unless rotations were reduced. In a longer timeframe, the wood demands were projected to be easily satisfied in the less ambitious climate change mitigation scenarios. In contrast, the demand in the ambitious mitigation scenario could not be met with current management practices, not even if all owners managed their production forests at the intensive extreme of current management approaches. The climate change mitigation scenarios provide very different trajectories with respect to future drivers of forest management. Our results indicate that with less ambitious mitigation efforts, the relatively intensive practices in the study region can be softened while ambitious mitigation might push for further intensification

    Downscaling of Long-Term Global Scenarios to Regions with a Forest Sector Model

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    Research Highlights: Long-term global scenarios give insights on how social and economic developments and international agreements may impact land use, trade, product markets, and carbon balances. They form a valuable basis for forming national forest policies. Many aspects related to long-term management of forests and consequences for biodiversity and ecosystem services can only be addressed at regional and landscape levels. In order to be attended to in the policy process, there is a need for a method that downscales national scenarios to these finer levels. Background and Objectives: Regional framework conditions depend on management activities in the country as a whole. The aim of this study is to evaluate the use of a forest sector model (FSM) as a method for downscaling national scenarios results to regional level. The national FSM takes the global scenario data (e.g., harvest level and market prices over time) and solves the national problem. The result for the region of interest is taken as framework conditions for the regional study. Materials and Methods: Two different specifications are tested. One lets product volumes and prices represent endogenous variables in the FSM model. The other takes volumes and prices from the global scenario as exogenous parameters. The first specification attains a maximum net social payoff whereas the second specification means that net present value is maximized under a harvest constraint. Results: The maximum net social payoff specification conforms better to economic factors than the maximum net present value specification but could give national harvest volume trajectories that deviates from what is derived from the global model. This means that regional harvest activity can deviate considerably from the national average, attesting to the benefit of the use of the FSM-based metho

    Material substitution between coniferous, non-coniferous and recycled biomass – Impacts on forest industry raw material use and regional competitiveness

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    The competitive advantage of traditional forest industry regions such as North America, Russia and the EU is based largely on the production and processing of coniferous (C) biomass. However, non-coniferous (NC) and recycled (R) biomass provide cost-effective alternatives to C biomass, which have already decreased the proportion of C biomass use and which can potentially have large impacts on the future development of the global forest sector. In this study, we investigate the impacts of material substitution between C, NC and R biomass on forest industry raw material use and regional competitiveness from 2020 to 2100. The analysis is based on a global spatially-explicit forest sector model (GLOBIOM-forest). Our results indicate that traditional forest industry regions can maintain their competitiveness in a baseline scenario where C and NC biomass remain imperfect substitutes, and the development of the circular economy increases the availability of R biomass. Limited availability of R biomass would increase the competitiveness of traditional forest industry regions relative to the baseline. On the other hand, a perfect substitution between C and NC biomass would decrease the competitiveness of traditional forest industry regions relative to the baseline, and increase the competitiveness of emerging forest industry regions such as South America, Asia and Africa. We also show that the increased availability of R biomass tends to decrease demand for pulpwood and might lead to an oversupply of pulpwood especially in traditional forest industry regions. This opens new perspectives for pulpwood use and/or forest management in these regions

    More future synergies and less trade-offs between forest ecosystem services with natural climate solutions instead of bioeconomy solutions

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    To reach the Paris Agreement, societies need to increase the global terrestrial carbon sink. There are many climate change mitigation solutions (CCMS) for forests, including increasing bioenergy, bioeconomy, and protection. Bioenergy and bioeconomy solutions use climate-smart, intensive management to generate high quantities of bioenergy and bioproducts. Protection of (semi-)natural forests is a major component of "natural climate solution" (NCS) since forests store carbon in standing biomass and soil. Furthermore, protected forests provide more habitat for biodiversity and non-wood ecosystem services (ES). We investigated the impacts of different CCMS and climate scenarios, jointly or in isolation, on future wood ES, non-wood ES, and regulating ES for a major wood provider for the international market. Specifically, we projected future ES given by three CCMS scenarios for Sweden 2020-2100. In the long term, fulfilling the increasing wood demand through bioenergy and bioeconomy solutions will decrease ES multifunctionality, but the increased stand age and wood stocks induced by rising greenhouse gas (GHG) concentrations will partially offset these negative effects. Adopting bioenergy and bioeconomy solutions will have a greater negative impact on ES supply than adopting NCS. Bioenergy or bioeconomy solutions, as well as increasing GHG emissions, will reduce synergies and increase trade-offs in ES. NCS, by contrast, increases the supply of multiple ES in synergy, even transforming current ES trade-offs into future synergies. Moreover, NCS can be considered an adaptation measure to offset negative climate change effects on the future supplies of non-wood ES. In boreal countries around the world, forestry strategies that integrate NCS more deeply are crucial to ensure a synergistic supply of multiple ES

    Climate targets in European timber-producing countries conflict with goals on forest ecosystem services and biodiversity

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    The role of increased timber harvests in reaching climate mitigation targets for European countries will be limited if the protection of forest ecosystem services and biodiversity is to be achieved, suggests an empirical forest model driven by future scenarios to limit warming to 1.5 degrees C in 2100.The European Union (EU) set clear climate change mitigation targets to reach climate neutrality, accounting for forests and their woody biomass resources. We investigated the consequences of increased harvest demands resulting from EU climate targets. We analysed the impacts on national policy objectives for forest ecosystem services and biodiversity through empirical forest simulation and multi-objective optimization methods. We show that key European timber-producing countries - Finland, Sweden, Germany (Bavaria) - cannot fulfil the increased harvest demands linked to the ambitious 1.5 degrees C target. Potentials for harvest increase only exists in the studied region Norway. However, focusing on EU climate targets conflicts with several national policies and causes adverse effects on multiple ecosystem services and biodiversity. We argue that the role of forests and their timber resources in achieving climate targets and societal decarbonization should not be overstated. Our study provides insight for other European countries challenged by conflicting policies and supports policymakers
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