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[en] The capital cost of small scale biomass fired systems is currently significantly higher than equivalent rated fossil fuel fired systems. If the cost of producing willow or poplar coppice derived fuel can be shown to offer significant savings over the cost of conventional fossil fuel alternatives, the resultant total cost of energy production could in fact be less. The production of ''home grown'' fuel should always, in theory, be cheaper than bought in supplies due to the removal of cost components such as profit and risk and the possible use of labour during traditionally quiet periods on the farm. However, it has not been shown to date that small scale coppice plantations can successfully produce cost effective wood fuel to displace fuel that would otherwise be 'bought in'. It is likely that fuel from coppice will be harvested on a semi-manual basis using brush cutters and farm loaders etc. This report identifies appropriate systems and provides estimates of the key costs to a grower. Particular emphasis is given to operations surrounding cut-back, harvesting and comminution. The report provides an outline of the statutory requirements of employers engaged in coppice management. Key costs have been presented in their most useful form for a potential grower to compile enterprise gross margins. (Author)
[en] Eucalyptus plantations are extensively managed for wood production in the central highlands of Ethiopia. Nevertheless, little is known about their biomass (dry matter) production, partitioning and dynamics over time. Data from 10 different Eucalyptus globulus stands, with a plantation age ranging from 11 to 60 years and with a coppice-shoot age ranging from 1 to 9 years were collected and analyzed. Above-ground tree biomass of 7-10 sampled trees per stand was determined destructively. Dry weights of tree components (Wc; leaves, twigs, branches, stembark, and stemwood) and total above-ground biomass (Wa) were estimated as a function of diameter above stump (D), tree height (H) and a combination of these. The best fits were obtained, using combinations of D and H. When only one explanatory variable was used, D performed better than H. Total above-ground biomass was linearly related to coppice-shoot age. In contrast a negative relation was observed between the above-ground biomass production and total plantation age (number of cutting cycles). Total above-ground biomass increased from 11 t ha-1 at a stand age of 1 year to 153 t ha-1 at 9 years. The highest dry weight was allocated to stemwood and decreased in the following order: stemwood > leaves > stembark > twigs > branches. The equations developed in this study to estimate biomass components can be applied to other Eucalyptus plantations under the assumption that the populations being studied are similar with regard to density and tree size to those for which the relationships were developed
[en] During the last three decades, driving forces behind the development of short-rotation willow coppice (SRWC) in Sweden have been changing from a primary focus on biomass production towards emphasis on environmental applications. In most cases, current commercial SRWC practice is geared towards a combination of biomass production for energy purposes and environmental goals. The latter goals range from decreasing the impact of specific contaminants in the environment to organic waste handling in a recycling system in urban and/or agricultural areas. Where biomass production and pollutant management overlap, the science of phytoremediation has its practical application. Through phytoremediation, waste products that previously have been a burden for society can be used as valuable resources to increase short-rotation willow biomass production. In this paper we will present the terminology and definitions of different types of phytoremediation. We also give an overview of five different cases of phytoremediation activities with a potential for large-scale implementation. Some of the types of activities are already commercially used in Sweden; others seem promising but still need further development. (Author)
[en] The experiment was carried out on a short rotation coppice culture of poplars (POP-EUROFACE, Central Italy), growing in a free air carbon dioxide enriched atmosphere (FACE). The specific objective of this work was to study whether elevated CO2 and fertilization (two CO2 treatments, elevated CO2 and control, two N fertilization treatments, fertilized and unfertilized), as well as the interaction between treatments caused an unbalanced nutritional status of leaves in three poplar species (P. x euramericana, P. nigra and P. alba). Finally, we discuss the ecological implications of a possible change in foliar nutrients concentration. CO2 enrichment reduced foliar nitrogen and increased the concentration of magnesium; whereas nitrogen fertilization had opposite effects on leaf nitrogen and magnesium concentrations. Moreover, the interaction between elevated CO2 and N fertilization amplified some element unbalances such as the K/N-ratio. - CO2 enrichment reduced foliar nitrogen and increased the magnesium concentration in poplar
[en] The ''Wood as a Fuel'' programme - which funded the research covered in this report - is one of the renewable energy development programmes managed by ETSU (the Energy Technology Support Unit) for the Department of Trade and Industry. This national programme is developing the production and use of fuel wood from two main sources - forestry residues and short rotation coppice. Wood fuel from short rotation coppice offers the greater potential - energy equivalent to 10 mtce (million tonnes of coal equivalent) could be produced annually from 1 million hectares of land. This programme is now well established, with ten trial coppice sites in operation, plus some 40 others. A number of successfully willow and poplar clones have been selected for different soil conditions, and machinery for planting and harvesting has been developed. Local consortia of farmers and users are being established to provide long-term markets for the wood fuel produced. (author)
[en] Highlights: • Forest coppicing allow to replace fossil fuels with renewable energy sources. • We tested which factors drive the probability and vigor of beech sprouting in the Italian Alps. • Sprouting decreased with poor soils, higher precipitation and increasing stool size. • When one or more shoots were left, 82% of the stools sprouted. • This evidence can be used to sustainably manage beech coppices for biomass. - Abstract: Interest in coppices is growing due to the need to replace fossil fuels with renewable energy sources. In Italy, beech covers one million hectares, half of which originated by coppicing. This study tested which factors drive the presence and growth of beech resprouts, with a focus on fertility, cutting intensity, age, and size at time of coppicing. We analyzed 509 stools in 24 stands coppiced between 1 and 26 years before sampling. We fitted Generalized Linear Mixed Models of the probability of sprouting and height of the tallest resprout for each stool as a function of elevation, slope, aspect, bedrock, precipitation, temperature, age at coppicing, time since coppicing, residual shoot density, the sum, average and coefficient of variation of the diameter of cut shoots, and type of stool treatment. Of all harvested stools, 249 (49%) had sprouted with an average of 7.6 resprouts per stool. Height of the tallest resprout on each stool ranged from 3 to 800 cm, mainly as a function of time since coppicing. Resprout mortality was on average 1.4% per plot. Sprouting decreased with decreasing site fertility, increasing precipitation, and increasing size of cut stems. Leaving one or more shoots on the stool after felling produced a high proportion of sprouting stools (82%). Although based on a limited sample, our quantitative analysis of the driving factors of sprouting in beech can be used to support silvicultural decisions in over-mature beech coppices, and to optimize trade-offs between ecosystem services such as biomass production, biodiversity, and hydro-geologic protection.
[en] Predicting the economic viability and environmental sustainability of a biofuels industry based on intensively cultivated short rotation woody crops (SRWC) requires spatial predictions of growth and yield under various environmental conditions and across large regions. The Physiological Principles in Predicting Growth (3PG) model was modified to evaluate the growth and yield of coppiced poplar (Populus spp). This included an additional biomass partitioning method and developing a sub-model which takes into account the impact of coppicing on post harvest regeneration, extending the applicability of the 3PG model to coppice management regimes. The parameterized model was applied to the entire Pacific Northwest of the United States, using appropriate climate and soil input data. Results predict the yield of poplar cultivation at a spatial resolution of ≈64 km"2 throughout the ≈8,000,000 km"2 of the study region. Existing agricultural cultivation patterns were used to estimate regional water availability for irrigation, and for non-irrigated regions, land cover features including ownership, slope, soil salinity and water table depth where used to select areas with a real potential to support a SRWC plantation. Results can be integrated with other models that allow for optimizing crop selection and biorefinery site selection. Important results include; an updated 3PG model for coppiced SRWC plantings, estimates of biomass feedstock yields under different irrigation patterns and weather conditions, and estimates for feedstock availability when combined with crop adoption scenarios. - Highlights: • A poplar growth model was applied to the Pacific Northwest of the US. • We included a coppicing module to the exsiting 3PG growth model. • We investigated growth under irrigated and non-irrigated conditions. • We developed Geospatial yield estimates. • We discuss changes in yield from climate change
[en] LAI is a key factor in light and rainfall interception processes in forest stands and, for this reason, is called to play an important role in global change adaptive silviculture. Therefore, it is necessary to develop practical and operative methodologies to measure this parameter as well as simple relationships with other silviculture variables. This work has studied 1) the feasibility of LAI-2000 sensor in estimating LAI-stand when readings are taken under direct sunlight conditions; and 2) the ability of LAI in studying rainfall partitioned into throughfall (T) in an Aleppo pine stand after different thinning intensities, as well as its relationships to basal area, (G), cover (FCC), and tree density (D). Results showed that the angular correction scheme applied to LAI-2000 direct-sunlight readings stabilized them for different solar angles, allowing a better operational use of LAI-2000 in Mediterranean areas, where uniform overcast conditions are difficult to meet and predict. Forest cover showed the highest predictive ability of LAI (R2 = 0.98; S = 0.28), then G (R2 = 0.96; S = 0.43) and D (R2 = 0.50; S = 0.28). In the hydrological plane, T increased with thinning intensity, being G the most explanatory variable (R2 = 0.81; S = 3.07) and LAI the one that showed the poorest relation with it (R2 = 0.69; S = 3.95). These results open a way for forest hydrologic modeling taking LAI as an input variable either estimated form LAI-2000 or deducted from inventory data. (Author) 36 refs.
[en] In this study, we examined the possibility of classifying representative tree species at Satoyama coppice forest based on spectral reflectance of the tree species. We used the airborne hyperspectral data observed in exhibition leaf stage at the test forest (about 3.4ha) in Tama Forest Science Garden (Hachioji, Tokyo) , where the forest type similar to that of Satoyama is preserved. The classification accuracy was verified by comparing the results of interpretation of color aerial photographs taken in spring and autumn in chronological order and the field survey. As a result, the 534-556 nm (band 6 and band 7) in the visible range and 739-762 nm (band 15 and band 16), 785nm (band 17) in the near infrared range are effective bands for classification of the species of such trees as Castanopsis sieboldii, Quercus glauca, Zelkova serrata, Quercus serrata, Cryptomeria japonica, and Chamaecyparis obutusa, which are representative trees in Satoyama coppice forest in Tama district