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Methods to assess wood-based bioenergy projects have tended to focus on technological and physical constraints. Less is known about how longer-term environmental, economic, and social systems—the three pillars of sustainable development—have influenced technological development in the context of woody biomass energy. This research offers new methods for assessing the sustainability of wood-based energy projects by combining spatial analysis, semi-structured interviews, and archival data analysis. By integrating quantitative and qualitative methods, this project offers ways to understand how social and environmental dynamics from the past shape technological development in the future. A propensity analysis of biomass energy plants in Michigan, USA was performed using US Census data grouped by social, economic, and environmental categories. This quantitative analysis helped to characterize community and landscape types in which woody biomass plants were developed in Michigan in the late-twentieth century. To help illustrate some of the often-hidden social and political dimensions of energy development, such as access to decision-making and attitudes toward bioenergy projects, transcripts of public hearings, media coverage, and other archival sources were examined, and 30 stakeholder interviews were conducted. By integrating these qualitative and quantitative approaches, this paper aims to provide a more comprehensive approach to assessing the sustainability of wood-based biofuel technologies.

We compare sustainably managed with unmanaged forests in terms of their contribution to climate change mitigation based on published data. For sustainably managed forests, accounting of carbon (C) storage based on ecosystem biomass and products as required by the United Nations Framework Convention on Climate Change is not sufficient to quantify their contribution to climate change mitigation. The ultimate value of biomass is its use for biomaterials and bioenergy. Taking Germany as an example, we show that the average removals of wood from managed forests are higher than stated by official reports, ranging between 56 and 86 mill. m3 year−1 due to the unrecorded harvest of firewood. We find that removals from one hectare can substitute 0.87 m3 ha−1 year−1 of diesel, or 7.4 MWh ha−1 year−1, taking into account the unrecorded firewood, the use of fuel for harvesting and processing, and the efficiency of energy conversion. Energy substitution ranges between 1.9 and 2.2 t CO2 equiv. ha−1 year−1 depending on the type of fossil fuel production. Including bioenergy and carbon storage, the total mitigation effect of managed forest ranges between 3.2 and 3.5 t CO2 equiv. ha−1 year−1. This is more than previously reported because of the full accounting of bioenergy. Unmanaged nature conservation forests contribute via C storage only about 0.37 t CO2 equiv. ha−1 year−1 to climate change mitigation. There is no fossil fuel substitution. Therefore, taking forests out of management reduces climate change mitigation benefits substantially. There should be a mitigation cost for taking forest out of management in Central Europe. Since the energy sector is rewarded for the climate benefits of bioenergy, and not the forest sector, we propose that a CO2 tax is used to award the contribution of forest management to fossil fuel substitution and climate change mitigation. This would stimulate the production of wood for products and energy substitution.

El trabajo pretende contribuir a que se conozcan y dimensionen aspectos claves del potencial de desarrollo de plantaciones dendroenergéticas en la Argentina, sobre la base de conocimiento científico acerca de la silvicultura de bosques cultivados, su relación con el ambiente, el análisis de los aspectos económicos y el desarrollo de proyectos de generación de energía a partir de biomasa. Para su elaboración se contemplaron cuatro objetivos: • regionalizar las áreas potencialmente elegibles para plantaciones dendroenergéticas con las especies introducidas de mayor conocimiento y difusión; • elaborar modelos técnico-económicos de esta actividad; • desarrollar modelos alternativos de transformación energética a partir de biomasa forestal; • analizar las regulaciones que se relacionan directa o indirectamente con la actividad de forestación dendroenergética. Centro de investigación en economía y prospectiva Fil: Casellas, Karina Susana. Instituto Nacional de Tecnología Agropecuaria (INTA). Centro de Investigación en Economía y Prospectiva (CIEP); Argentina Fil: Lupi, Ana Maria. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Suelos; Argentina Fil: Olemberg, Demián Jeremías. Instituto Nacional de Tecnología Agropecuaria (INTA). Centro de Investigación en Economía y Prospectiva (CIEP); Argentina Fil: Gyenge, Javier Enrique. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Agencia de Extensión Rural Tandil; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. International Associate Laboratory, FORESTIA; Argentina Fil: Fernandez, Roberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Montecarlo; Argentina Fil: Fassola, Hugo Enrique. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Montecarlo; Argentina Fil: Zaderenko, Constantino. Universidad Nacional de Misiones. Facultad de Ciencias Forestales; Argentina Fil: Navarro, Marí­a Fabiana. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Suelos; Argentina

Aim of the study: The objective of this paper is to investigate the use of Biomass Conversion and Expansion Factors (BCEFs) in maritime pine (Pinus pinaster Ait.) stands subjected to thinning.Area of the study: The study area refers to different ecosystems of maritime pine stands inNorthern Portugal.Material and methods: The study is supported by time data series and cross sectional data collected in permanent plots established in the North of Portugal. An assessment of BCEF values for the aboveground compartments and for total was completed for each studied stand. Identification of key variables affecting the value of the BCEFs in time and with thinning was conducted using correlation analysis. Predictive models for estimation of the BCEFs values in time and after thinning were developed using nonlinear regression analysis.Research highlights: For periods of undisturbed growth, the results show an allometric relationship between the BCEFs, the dominant height and the mean diameter. Management practices such as thinning also influence the factors. Estimates of the ratio change before and after thinning depend on thinning severity and thinning type. The developed models allow estimating the biomass of the stands, for the aboveground compartments and for total, based on information of stand characteristics and of thinning descriptors. These estimates can be used to assess the forest dry wood stocks to be used for pulp, bioenergy or other purposes, as well as the biomass quantification to support the evaluation of the net primary productivity.Keywords: carbon; softwood; thinning; volume; wood energy; maritime pine.

A demanda mundial por energia limpa e sustentável tem aumentado nos últimos anos. Uma das alternativas é a biomassa, incluindo os plantios florestais, com destaque, no Brasil, para o gênero Eucalyptus spp., que, atualmente, possui diversos clones selecionados para a produção de energia. Em razão da diferença na adaptação dos clones aos diferentes ambientes, há necessidade de estudos específicos para avaliar a produção de energia para determinada região. Objetivou-se, neste estudo, determinar dentre seis clones de Eucalyptus urophylla S. T. Blake analisados, aqueles com maior potencial para a produção de biomassa e energia para a região Centro Sul do Maranhão (Grajaú). Os clones foram avaliados com 41 meses de idade, plantados em espaçamento de 4 x 3 m, e distribuídos em delineamento inteiramente casualizado, com cinco repetições. Cada parcela experimental era composta por 100 árvores. Foram determinadas a produção e a alocação de biomassa de cada parte da árvore e o poder calorífico de casca e do lenho. Dos seis clones estudados, dois se destacaram tanto na produção de biomassa, quanto para a geração de energia, sendo superiores em até 27 % em comparação com o clone de menor rendimento. The worldwide demand for clean, sustainable energy has increased in recent years. A potential alternative energy source is biomass from nonnative forests, particularly from the genus Eucalyptus spp. in the specific case of Brazil, currently with several selected clonal stands for energy production. Because each stand adapts differently to different environments, specific studies are required in order to evaluate energy production in a given region. The objective of this study is to determine, from among six clonal stands of Eucalyptus urophylla S. T. Blake, which have greater potential for production of biomass and energy in the South Central region of Maranhão (Grajaú). Clonal stands planted at a spacing of 4 x 3 m apart were evaluated at age 41 months, distributed in a completely randomized design with five replicates. Each experimental plot consisted of 100 trees. Analysis included determining biomass yield and distribution in each tree portion as well as calorific value of bark and wood components. Out of the six clonal stands, two outdid the others both in biomass yield and in energy generation, surpassing the least yielding stand by up to 27%. ANDRADE, T. C. G. R. Universidade Federal do Pará

Congo Basin countries rely more on wood-based biomass to meet their energy needs than most other countries in the world. Wood fuel production is increasing in Congo Basin countries. Urbanization often produces a shift from fuel wood to charcoal consumption, because charcoal is cheaper and easier to transport and store. Charcoal is produced mostly using traditional techniques, with low transformation efficiencies. Under a business as usual scenario, charcoal supply can represent the single biggest threat to Congo Basin forests in the coming decades. This report aims at providing some thinking on how Congo Basin could meet their energy needs in a forest-friendly manner. It is one of a series of outputs prepared during a two-year exercise to analyze and better understand the deforestation dynamics in the Basin. It presents the main findings related to the wood fuel sector in the Congo Basin and its potential impact on forest cover. It is based on an in-depth analysis of the sector (past trends and future prospects). It also builds on results derived from a modeling exercise conducted by the International Institute for Applied Systems Analysis (IIASA) that examined the national and regional trends in in wood-based biomass energy use and the impacts on Congo Basin forests. The report is structured as follows: chapter one gives an overview of the wood fuel sector in the six Congo Basin countries, including an analysis of its impact so far on forest cover; chapter two presents the prospects of energy needs and production in the near future, and the potential impacts on forest under a business as usual scenario; and chapter three identifies potential key levers in the wood fuel sector that could limit adverse impacts on forest cover.

[EN] The aim of this work was to evaluate the amount of residual biomass obtained from citrus tree plantations. This amount is influenced by the variety and aim of the pruning. The trials show that the amount of pruned biomass can be considered similar in the varieties Naveline and Washington Navel, giving an average 4.73 kg per tree and 2.68 tons per hectare. The Valencia Late produced about 48% more than the other evaluated varieties. The amount of residual biomass per tree obtained in formation pruning was about 49% lower than the trees in full production, giving 4.7 tons of dry biomass per hectare. Furthermore, the amount of pruned biomass from mandarin varieties studied show that they can be classified two groups. Varieties Clemenvilla and Owall form the first homogeneous group with bigger amount of residues with average 9.6 kg per tree and 6.9 tons per hectare, while the second homogeneous group included by the rest of varieties, with 3.8 kg per tree and 2.9 tons per hectare. Factors, such as age or growing space per tree increase the wood residues production to 66% and 53.3%, respectively, in mandarin trees. Regression equations have been modeled to predict the available biomass per tree and per hectare from dendrometic characteristics of the trees. The coefficients of determination have been acceptable. The drying process of pruned materials has been depicted. The density and gross power heat have been measured. The information offered by these equations is of vital importance to estimate the amount of biomass that is generated in a given area, and for implementing GIS maps. In addition, logistic algorithms can be applied., The techniques shown in this paper were developed by the project AGL2007-62328 funded by the Ministry of Education and Science of Spain, and FEDER funds