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This is the longest continuous experiment where ethylenediurea (EDU) was used to protect plants from ozone (O3). Effects of long-term ambient O3 exposure (23 ppm h AOT40) on biomass of an O3 sensitive poplar clone (Oxford) were examined after six years from in-ground planting. Trees were irrigated with either water or 450 ppm EDU. Above (-51%) and below-ground biomass (-47%) was reduced by O3 although the effect was significant only for stem and coarse roots. Ambient O3 decreased diameter of the lower stem, and increased moisture content along the stem of not-protected plants (+16%). No other change in the physical wood structure was observed. A comparison with a previous assessment in the same experiment suggested that O3 effects on biomass partitioning to above-ground organs depend on the tree ontogenetic stage. The root/shoot ratios did not change, suggesting that previous short-term observations of reduced allocation to tree roots may be overestimated.

In the alpine Autonomous Province of Bolzano (N-E Italy), about 40 % of the biomass used for bioenergy production is currently imported. This share is expected to further increase in the near future owing to growing renewable energy needs. The residual biomass harvestable from the local agronomic sector, mostly based on the cultivation of apple, is a promising option to supply relatively cheap bioenergy feedstock. In this study, we investigate the use of woody residues from apple orchards (apple orchard´s woody residues, AWRs) for the production of bioenergy using the life cycle assessment (LCA) methodology. The system boundaries include the harvesting and chipping of AWRs, their transport to the energy plant and conversion into heat and power in a gasification unit. The life cycle inventory (LCI) data rely on field measurements for AWRs harvesting and chipping operations, as well as for their chemical and energy characterization. In the life cycle impact assessment (LCIA) phase, we consider various environmental impact categories like climate change, acidification, fossil depletion, and others. We benchmark the outcomes with two alternative reference systems based on fossils fuels. Our results show that the energy production using AWRs generally presents better environmental indicators than the reference systems, although some trade-offs exist. For instance, whereas the bioenergy system saves up to about 85% of greenhouse gas (GHG) emissions and about 95% of non-renewable resources, it is usually associated with higher toxicity impact potentials.

Biomass, typically obtained from fast growing plants or over-stocked agricultural products, has been widely recognised as a replacement for traditional energy sources. The challenge is, however, to provide biomass feedstock with optimised properties best suited for downstream conversion. Willow ( Salix sp.) is one of the most common hardwood species suitable for short-rotation forestry. The goal of this research was to explore the potential of the near infrared (NIR) spectroscopy to evaluate the chemical composition of several willow clones. It was shown that near infrared spectroscopy can be an alternative technique to standard analytical methods supporting research and development of biomass production technologies. Partial least squares (PLS) regression models for quantitative prediction of wood components (lignin, cellulose, holocellulose, pentosans and extractive components soluble in hot/cold water, 1% NaOH and organic solvents) were developed. Using NIR spectroscopy, it was possible to discriminate different willow clones and to assign these into groups by means of principal components analysis (PCA).

This study provides a state-of-the art overview of forest biomass harvesting technologies and supply chains used in North America, Europe and the Southern Hemisphere. The productivity and cost of selected efficient technologies is presented for each country with a brief description about the source of the biomass and harvesting method. Expert opinions on the most successful biomass operations have been presented briefly for each country. The main conclusions from various intentional studies are provided in addition to future requirements for research and development. This report can be a useful high level guide of technology and supply chain selection for industry and academics.

The Doge's Palace of Venice (Italy) has on its canal-side large doorways closed by old wooden doors. Originally, the thresholds were built above high-water level to avoid direct contact with the water and the resulting damage caused by physical and biological agents. As a result of sea-level rise and land subsidence during the last centuries, the doors are now exposed to tides and to attack by marine wood-boring invertebrates such as shipworms and gribbles. As a consequence, the bottom rails of the doors were recently in need of substantial restoration, which took into consideration new materials and techniques. In this framework, an in situ experiment was undertaken to test the resistance of some selected wood species to woodboring organisms. A quick assessment protocol, based on the EN 275 standard, was set up to quantify bioerosion according to wood species and elevation above sea level. Both European and tropical wood species were tested. The former include Scots Pine, as a reference, and Larch, Cypress and Oak as traditional carpentry materials. The latter include Azobe, Okan, and Bilinga. All the European species showed high susceptibility to woodborer attack, whereas no damage was recorded on the tropical woods. The collected shipworms belonged mostly to Lyrodus pedicellatus and Teredo bartschi with some individuals of Teredo navalis. The only species of gribble found was Limnoria tripunctata. New technical solutions were adopted in the restoration aiming to provide a long service life for the replacements and simplifying the maintenance procedures. Experience, results and solutions are presented.

This paper offers a forest operations perspective in environmentally sensitive areas (ESAs) in Europe and the United States. The objective is to help inform key sustainability knowledge gaps in forest operations to reduce impacts on the environment and the equipment operators in these increasingly targeted and difficult to operate in areas. Under existing guidelines and best management practices, the protection of ecosystem services linked to soil, water, wildlife and biodiversity have rightly received the highest considerations. However, the connection between protecting these ecological values, safe operational practices and technological advancements is rarely well articulated. One means to address the operational and technological gap is the selection of equipment and tailor the work conditions to terrain type, forest features and management objectives. To that effect, this paper discusses the environmental, planning, equipment selection and operator considerations and proposes possible solutions and guidelines to contain both the operators' safety and environmental risks in forest operations.

We observed over 100 wood chipping operations, using time-and-motion methods to quantify their productivities, and interviews and observations to subjectively evaluate the factors that affect their existance and character. Productive time per green tonne decreased with increases in both chipper power and piece size. In Italy, chipping has evolved from a primary business for contractors who processed whole trees, to a secondary activity for loggers who dispose of residues by chipping them for particleboard. In recent years, biomass-fueled district heating plants in northern Italy have been added to the mix of users, and larger electric power plants may expand the chipping industry in the near future. Operators who heavely utilize chippers prefer self-propelled machines. Tractor-powered and towed chippers are used in a wide range of conditions, but the latter are restricted to landings while the former are employed at landings and within stands. Disc chippers have dominated the industry, but drum chippers are making inroads, especially in fuel supply operations. Chips are transported by farm tractors and powered trailers when distances are short (up to 3-4 km), by high-speed tractors for intermediate distances, and by trucks for distances over 30 km.

Nine chippers were tested for particle size distribution, in order to a) see how chips produced with these machines matched the quality specifications set by the district heating plants of Northeastern Italy and b) detect significant differences between machines. The benchmark was set by collecting chip samples from fourteen district heating plants in the region of interest. The effect of operator skill was minimized and all machines were fed with the same assortment: logs, supplied in lengths varying between 2.4 and 6 m. All logs had similar moisture contents, which typically ranged between 33 and 37 % on a fresh weight base. Mobile in-woods chippers fed with limb-free logs produce high-quality chips, whose particle size distribution matches that of the best chips normally fed to the Italian district heating plants. Indeed, all the tested machines produced chip samples containing almost no oversize particles, very little fines (0.5 to 1 %), and a large majority of chips within the 3-45mm range (95 to 99 %), except the auger-equipped Laimet, which is designed to produce larger chips. There were statistically significant differences between machines and machine types, which were not affected by possible variations of the tree species processed.