Stork M.,University of Heidelberg |
Schulte A.,Free University of Berlin |
Murach D.,Eberswalde University Of Applied Sciences
Biomass and Bioenergy | Year: 2014
Woody biomass (dendromass) today already has an important role in bioenergy production and will even increase in the future as a renewable resource for energetic as well as for material use. In eastern Germany, an increasing demand for dendromass in renewable energy production is unlikely to be covered by sustainable forest wood production. Hence, a deficit for the federal state of Brandenburg of 4.02 million tonnes per year is predicted. Besides imports, one option of increasing dendromass supply in Brandenburg is short rotation coppice (SRC) on arable land. The potential of SRC on arable land is determined by the economic competitiveness of SRC compared to conventional annual crops. This factor is strongly influenced by the water supply, expressed as the transpiration water supply (TWS) in the growing season, and the soil quality. First evaluations of SRC potentials in Brandenburg identify large areas of arable land where SRC seems to be able to compete with annual crops. Potential areas in the Dahme river catchment, located in the south of Berlin, were identified at a regional scale through a GIS-based approach. The results indicate that lowland river catchments like the Dahme basin have great potentials for fuelwood production. Especially the large amount of arable land with accessible groundwater resources offers water for transpiration in a region where average annual precipitation and water storage capacity of soils is relatively low (550mm and 100-150mmm-1 resp.) and thus too small to meet the demands of optimal SRC growth. In total, 340,000 tonnes fuelwood could be produced annually in the Dahme river catchment, if all potential sites were transformed into SRC. This accounts for 8.5% of the deficit produced on just 1.8% of the federal state of Brandenburg's total agricultural area by 2030 and meet the heating energy demand of approximately 130,000 people. The results show that the applied method is an effective way to identify biomass potentials in mesoscale river basins and demonstrates the relevance of the Dahme catchment for a sustainable energy supply in the future. © 2014 Elsevier Ltd.
Pfriem A.,Eberswalde University Of Applied Sciences
Drvna Industrija | Year: 2015
The unique mechanical and acoustical properties of wood and its aesthetic appeal still make it the material of choice for musical instruments. Here tropical hardwoods are typically used in musical instruments. This paper gives an overview of how the use of thermally modified wood can contribute to the use of raw materials for musical instruments. It is shown that a mild thermal treatment leads to clear changes of the measurable acoustic characteristics, such as Young’s modulus, damping and sound velocity. In conclusion, thermally modified wood (mild treatment) is a material with favorable characteristics for making musical instruments. © 2015, Journal Drvna Industrija. All rights reserved.
Lawes M.J.,Charles Darwin University |
Richards A.,CSIRO |
Dathe J.,Eberswalde University Of Applied Sciences |
Midgley J.J.,University of Cape Town
Plant Ecology | Year: 2011
We investigated the fire resistance conferred by bark of seven common tree species in north Australian tropical savannas. We estimated bark thermal conductance and examined the relative importance of bark thickness, density and moisture content for protecting the cambium from lethal fire temperatures. Eucalypt and non-eucalypt species were contrasted, including the fire-sensitive conifer Callitris intratropica. Cambial temperature responses to bark surface heating were measured using a modified wick-fire technique, which simulated a heat pulse comparable to surface fires of moderate intensity. Bark thickness was a better predictor of resistance to cambial injury from fires than either bark moisture or density, accounting for 68% of the deviance in maximum temperature of the cambium. The duration of heating required to kill the cambium of a tree (τ c) was directly proportional to bark thickness squared. Although species did not differ significantly in their bark thermal conductance (k), the thinner barked eucalypts nevertheless achieved similar or only slightly lower levels of fire resistance than much thicker barked non-eucalypts. Bark thickness alone cannot account for the latter and we suggest that lower bark moisture content among the eucalypts also contributes to their apparent fire resistance. Unique eucalypt meristem anatomy and epicormic structures, combined with their bark traits, probably facilitate resprouting after fire and ensure the dominance of eucalypts in fire-prone savannas. This study emphasises the need to take into account both the thermal properties of bark and the mechanism of bud protection in characterising the resprouting ability of savanna trees. © 2011 Springer Science+Business Media B.V.
Pfriem A.,Eberswalde University Of Applied Sciences |
Dietrich T.,TU Dresden |
Buchelt B.,TU Dresden
Holzforschung | Year: 2012
The densification of wood leads to better mechanical properties, e.g., an increased hardness and dimensional stability. However, densified or shaped wood in contact with water springs back into its original shape without fixation. Hence, the aim of this study was the development of a combined densification and fixation procedure. Beech wood samples (Fagus sylvatica L.) were impregnated with a solution consisting of furfuryl alcohol and maleic anhydride. The compression of these impregnated samples to approximately 30 followed by a curing process in a heating press resulted in a significant increase of hardness and dimensional stability. The spring-back-effect was clearly reduced by the in situ polymerization of the furfuryl alcohol solution to furan resins. © 2012 by Walter de Gruyter Berlin Boston 2012.
Richards A.E.,CSIRO |
Dathe J.,Eberswalde University Of Applied Sciences |
Soil Biology and Biochemistry | Year: 2012
Soil respiration (R s) is the second-largest source of CO 2 to the atmosphere in terrestrial systems. In tropical savannas seasonal moisture availability and frequent fires drive ecosystem dynamics and may have a considerable impact on soil carbon (C) cycling, including R s. In order to test the effect of fire on soil C cycling we measured R s in annually burnt and unburnt plots in wet and dry seasons at a long-term fire experiment established in savanna woodlands of northern Australia. There was a significant interaction between season and fire, with highest rates of daily R s (722 mmol CO 2 m -2 d -1) observed in the wet season on unburnt, leaf litter patches. The three fold higher R s rate on unburnt plots in the wet season was due to greater root-derived respiration (R root: 356 mmol CO 2 m -2 d -1), while smaller changes to soil-derived respiration (R soil: 51 mmol CO 2 m -2 d -1) were simply the result of C moving through decomposition rather than combustion pathways. Relationships between instantaneous R s and soil temperature showed hysteresis with variable direction, suggesting that season and fire treatment also influence the soil depth at which CO 2 is produced. We suggest that (1) changes to fire regimes, through active management or climate change, in tropical savannas could have an impact on R s, and (2) the direct effect of fire on soil C cycling is limited to the removal of aboveground litter inputs. © 2012.