@article{IbischDichteHamoretal.2021, author = {Ibisch, Pierre L. and Dichte, Angela and Hamor, Fedir D. and Holovko, Andrii and Pokynchereda, Vasyl F. and Ryback, Mykola P. and Shvediuk, Iuliia}, title = {About borders and limits: experiences with UNESCO Biosphere Reserves for transboundary cooperation in Ukraine and neighbouring countries}, series = {eco.mont - Journal on Protected Mountain Areas Research and Management}, volume = {13}, journal = {eco.mont - Journal on Protected Mountain Areas Research and Management}, publisher = {Verlag der {\"O}sterreichischen Akademie der Wissenschaften}, issn = {2073-1558}, doi = {10.1553/eco.mont-13-sis136}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2508}, pages = {136 -- 141}, year = {2021}, abstract = {In Eastern Europe, several UNESCO Biosphere Reserves (BRs) have been important promoters of transnational and transboundary nature conservation and sustainable development. Nevertheless, political and institutional barriers and scarcity of resources have hindered successful cross-border cooperation. The prospects for BRs in Eastern Europe are mixed, especially in relation to the challenges of ecosystem degradation and climate change, as well as socioeconomic and (geo)political crises. Based on our own experience of one and a half decades of growing cooperation between partners in Ukraine and Germany, we conclude that transnational cooperation between BRs and science is particularly rewarding and mutually beneficial.}, language = {en} } @inproceedings{MunkWohlertPfriem2021, author = {Munk, Christoph and Wohlert, Hauke and Pfriem, Alexander}, title = {Investigation of the influence of two different thermal treatment processes on the change of various material properties of spruce resonance wood (Picea abies (L.) Karst.)}, series = {Northern European Network for Wood Science and Engineering - 17th Annual Meeting 2021}, booktitle = {Northern European Network for Wood Science and Engineering - 17th Annual Meeting 2021}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2909}, pages = {3}, year = {2021}, abstract = {In recent years, a large number of different studies have shown that a variety of positive property changes can be achieved by thermally treating spruce resonance wood. Various methods have been established, which differ mainly in the choice of treatment atmosphere, but also in the associated treatment duration and temperature. Part of the present investigation was to compare a thermal-vacuum process with a process which takes place in an oxygen-reduced atmosphere, with regard to various property changes. The results show that both processes achieved similar results in terms of dynamic acoustic property changes. Larger differences were found with regard to moisture behavior and color change.}, language = {en} } @inproceedings{MunkClauderPfriem2018, author = {Munk, Christoph and Clauder, Lothar and Pfriem, Alexander}, title = {Acoustical comparison of two different guitars, made of untreated tropical wood and thermally modified wood, using a frequency response analysis}, series = {Northern European Network for Wood Science \& Engineering (WSE)}, booktitle = {Northern European Network for Wood Science \& Engineering (WSE)}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2850}, year = {2018}, abstract = {To this day, many guitar makers around the world use primarily tropical woods such as rosewood (Dalbergia spp.) for their production. Due to the current CITES regulation of January 2017 regarding the trade of tropical woods, it becomes inevitable to generate alternative materials with similar material properties to be generated and established. Part of this study is an acoustic comparison of two guitars. One made of untreated tropical wood [Dalbergia nigra Benth.)] and one made of European thermally modified wood (TMT) species. [Pyrus (L.) and Alnus (Mill.)]. The method used allows a significant statement about the acoustic radiation performance of stringed and plucked instruments. The experimental setup consists of an impulse hammer for excitation of a force in the center of the bridge and a microphone for recording the signal radiated by the guitar body at a distance of one meter from the sound hole. A front-end was used to record the data, and further processing was done using analysis software to determine frequency response functions (FRFs) of the two instruments. The FRFs determined can be subdivided into several ranges which contain the different acoustic information about bass range, loudness, clarity, brightness and sharpness of the instruments. Examination of the frequency ranges reveals an acoustic similarity between the two guitars. Slight differences can be seen in the bass and loudness areas, where the guitar from TMT has a higher average level. Clearer differences are offered by the areas of clarity, where the guitar made of tropical wood shows a higher average level. In summary, the method gives an efficient acoustic impression as a function of the natural frequencies of the two guitars. The measured data show similarities and thus comparable acoustic properties of the instruments. However, additional effects such as psychoacoustic sensations or musical taste for the complete acoustic impression of an instrument are also of importance. Therefore, further empirical and fundamental research is needed to obtain a more detailed acoustic impression of the instruments.}, language = {en} } @inproceedings{MunkPfriem2022, author = {Munk, Christoph and Pfriem, Alexander}, title = {Influence of thermal modification and subsequent linseed oil impregnation on the sound propagation velocity and related acoustic properties of various wood species}, series = {Tenth European Conference on Wood Modification}, booktitle = {Tenth European Conference on Wood Modification}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2916}, year = {2022}, abstract = {In the field of instrument making, the use of indigenous wood species is becoming more and more important due to the increasing environmental awareness of instrument makers and their customers. As the properties of some of these wood species cannot meet the high demands of this field of application, processes are being sought that can achieve improvements. In recent years, many studies have shown that different modification methods, such as furfurylation, thermal treatment, densification or impregnation methods, can partly improve wood properties such as elasticity, strength values, damping behaviour, but also moisture behaviour and wood moisture content significantly. The extent to which different modification processes and their positive changes in properties can be combined with each other and thus achieve further improvements will become increasingly important in the future, not only in instrument making but also in other areas of application. Therefore, this study investigated the influence of thermal treatment followed by linseed oil impregnation of wood on its sound propagation velocity and the associated acoustic properties of characteristic impedance and acoustic radiation.}, language = {en} } @article{MissallWelpMehtaetal.2022, author = {Missall, Siegmund and Welp, Martin and Mehta, Kedar and Degembaeva, Nadira and Akmatov, Kuban and Z{\"o}rner, Wilfried}, title = {In Search for the Optimal Forest Use Behaviour: Riparian Forest Use in Central Asia, Using the Example of Ak-Tal, Naryn, Kyrgyzstan}, series = {Forests}, volume = {13}, journal = {Forests}, number = {8}, publisher = {MDPI}, issn = {1999-4907}, doi = {10.3390/f13081254}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-3508}, pages = {19}, year = {2022}, abstract = {Riparian forests are rare and valuable ecosystems in Central Asia, both due to their significance for biodiversity and to their provision of vital ecosystem services to local residents. However, the actual forest use behaviour is under-researched, official figures may not be trustworthy, and the question of over-use is up in the air. This paper sets out to shed light on riparian forest use behaviour by local residents using the example of Ak-Tal Village upon the Naryn River in Kyrgyzstan: Which economic use patterns do they practice (focusing on fuel wood and pasture)? Which other ecosystem services do they recognise? Is there forest over-exploitation? To answer these questions, this study builds on local knowledge, by applying the methods of focus group discussions and a household survey. Results show an extreme discrepancy between official wood consumption figures (50-60 m3 p.a.) and figures based on household wood consumption (310-404 m3 p.a.). The forest also serves as an important winter pasture over the seven months between October and April (stocking density 0.61 livestock units/ha), but payments for these ecosystem services are low, with annually 40 KGS/ha. Local residents are aware of additional material and nonmaterial ecosystem services of the riparian forest. Opinions diverge upon the question if there is forest over-exploitation, potentially because different stakeholders have different concepts of an optimal forest status. Consequently, optimal forest use behaviour can only be defined by the local users themselves, e.g., in a future stakeholder dialogue.}, language = {en} } @article{RussRiekWessolek2021, author = {Russ, Alexander and Riek, Winfried and Wessolek, Gerd}, title = {Three-Dimensional Mapping of Forest Soil Carbon Stocks Using SCORPAN Modelling and Relative Depth Gradients in the North-Eastern Lowlands of Germany}, series = {Applied Sciences}, volume = {11}, journal = {Applied Sciences}, number = {2}, publisher = {MDPI}, issn = {2076-3417}, doi = {10.3390/app11020714}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-3427}, pages = {28}, year = {2021}, abstract = {To cope with the challenges in forest management that are contemporarily caused by climate change, data on current chemical and physical soil properties are more and more necessary. For this purpose, we present a further amalgam of depth functions and SCORPAN modelling to provide data at arbitrary depth layers. In this concept, regionalisation is split up into the modelling of plot totals and the estimation of vertical distributions. The intended benefits by splitting up are: consistency between estimates on plot level and depth layer level, avoidance of artificial depth gradients, straightforward interpretation of covariates in the sense of pedogenetic processes, and circumnavigation of the propagation of uncertainties associated with separation between horizons during field sampling. The methodology was tailored to the circumstances within the north-eastern lowlands and the utilisation of current inventory data of the National Forest Soil Inventory (NFSI) in Brandenburg (Germany). Using the regionalisation of soil organic carbon (SOC) as an example, the application is demonstrated and discussed in detail. The depth to groundwater table and terrain parameters related to the catchment area were the main factors in SOC storage. The use of kriging did not improve the model performance. The relative depth gradients of SOC were especially distinguished by tree species composition and stand age. We suppose that interesting fields of application may be found in scenario-based modelling of SOC and when SOC serves as a basis for hydrological modelling.}, language = {en} } @article{RiekRussMarx2021, author = {Riek, Winfried and Russ, Alexander and Marx, Marc}, title = {Concentrations of Inorganic and Organic Pollutants in Forest Soils as an Archive of Anthropogenic Inputs in the State of Brandenburg, Germany}, series = {Applied Sciences}, volume = {11}, journal = {Applied Sciences}, number = {3}, publisher = {MDPI}, issn = {2076-3417}, doi = {10.3390/app11031189}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-3430}, pages = {22}, year = {2021}, abstract = {An important component of the National Forest Soils Inventory (NFSI) is the investigation of inorganic and organic pollutants. Forests are able to filter out large quantities of these substances from the atmosphere and incorporate them into the soil for a long time. The aim of this study was the integrative evaluation of organic and inorganic pollutant concentrations in forest soils in the state of Brandenburg, Germany. With the help of principle component analysis, the pollutant concentrations can essentially be explained by three significant environmental components, which explain 76\% of the total variance of all pollutants examined within the scope of the NFSI. The first component characterizes the extent of the atmospheric pollution caused by flue gases and fly ash from lignite combustion in the 1970s and 1980s and is mainly charged by the organic pollutants HCB and PAH, and the elements arsenic and chromium. This component shows positive relation to both spatially interpolated calcium-deposition data from the 1980s (as an indicator for the dust emission from coal combustion) and crown defoliation data of pine stands from the forest condition survey in the early 1990s. The depositions of zinc and cadmium from industrial sources, vehicle traffic and the use of fertilizers in agriculture mainly characterize the second principle component. The use of the pesticides DDT and lindane in the early 1980s and the associated pollutants input into the forest soils are expressed by the third component. In expanding the term archiving function of soils, the results illustrate their particular importance for the long-term archiving of anthropogenic inputs and the associated potential stress factors for forests.}, language = {en} } @article{BussolaFalcoAukesetal.2021, author = {Bussola, Francesca and Falco, Enzo and Aukes, Ewert and Stegmaier, Peter and Sorge, Stefan and Ciolli, Marco and Gagliano, Caterina and Geneletti, Davide}, title = {Piloting a more inclusive governance innovation strategy for forest ecosystem services management in Primiero, Italy}, series = {Ecosystem Services}, volume = {52}, journal = {Ecosystem Services}, publisher = {Elsevier}, doi = {10.1016/j.ecoser.2021.101380}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2531}, pages = {17}, year = {2021}, abstract = {Forests are increasingly recognized for their role, importance and multifunctionality in terms of provisioning, regulating and cultural ecosystem services they provide. Even if timber production remains the most economically valuable provisioning service in Primiero, the importance of and need for multifunctionality of forests is acknowledged. This article analyses the development of Forest Ecosystem Services (FES) governance innovation strategies by the Provincial Forest Agency as a policy entrepreneur in the area of Primiero, in Trentino, northeast of Italy. Based on detailed case study material, we create the heuristic of Kingdon's three streams model in order to reconstruct the development of and negotiations around the introduction of innovative approaches to the problem, policy and politics levels and to identify the chosen or missed windows of opportunity to deliver innovation in FES management. Findings show that the main issues perceived by the local stakeholders concern loss of biodiversity, of cultural identity and historical landscape values. The policy-entrepreneurial initiatives undertaken by the Forest Agency represent a governance mix of direct project execution, financial incentives, organisational incentives and information-based activities. The results highlight its efforts to move beyond the traditional top-down approach based on widely available public funds and towards coordination and collaborations among stakeholders, contribution of private investments, bureaucracy simplification and interconnection between participatory and institutional processes.}, language = {en} } @article{BoseScherrerCamareroetal.2021, author = {Bose, Arun K. and Scherrer, Daniel and Camarero, j. Julio and Ziche, Daniel and Babst, Flurin and Bigler, Christof and Bolte, Andreas and Dorado-Li{\~n}{\´a}n, Isabel and Etzold, Sophia and Fonti, Patrick and Forrester, David I. and Gavinet, Jordane and Gazol, Antonio and Gonz{\´a}lez de Andr{\´e}s, Ester and Karger, Dirk Nikolaus and Lebourgeois, Francois and L{\´e}vesque, Mathieu and Mart{\´i}nez-Sancho, Elisabet and Menzel, Annette and Neuwirth, Burkhard and Nicolas, Manuel and Sanders, Tanja G. M. and Scharnweber, Tobias and Schr{\"o}der, Jens and Zweifel, Roman and Gessler, Arthur and Rigling, Andreas}, title = {Climate sensitivity and drought seasonality determine post-drought growth recovery of Quercus petraea and Quercus robur in Europe}, series = {Science of The Total Environment}, volume = {784}, journal = {Science of The Total Environment}, publisher = {Elsevier}, issn = {1879-1026}, doi = {10.1016/j.scitotenv.2021.147222}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2609}, pages = {13}, year = {2021}, abstract = {Recent studies have identified strong relationships between delayed recovery of tree growth after drought and tree mortality caused by subsequent droughts. These observations raise concerns about forest ecosystem services and post-drought growth recovery given the projected increase in drought frequency and extremes. For quantifying the impact of extreme droughts on tree radial growth, we used a network of tree-ring width data of 1689 trees from 100 sites representing most of the distribution of two drought tolerant, deciduous oak species (Quercus petraea and Quercus robur). We first examined which climatic factors and seasons control growth of the two species and if there is any latitudinal, longitudinal or elevational trend. We then quantified the relative departure from pre-drought growth during droughts, and how fast trees were able to recover the pre-drought growth level. Our results showed that growth was more related to precipitation and climatic water balance (precipitation minus potential evapotranspiration) than to temperature. However, we did not detect any clear latitudinal, longitudinal or elevational trends except a decreasing influence of summer water balance on growth of Q. petraea with latitude. Neither species was able to maintain the pre-drought growth level during droughts. However, both species showed rapid recovery or even growth compensation after summer droughts but displayed slow recovery in response to spring droughts where none of the two species was able to fully recover the pre-drought growth-level over the three post-drought years. Collectively, our results indicate that oaks which are considered resilient to extreme droughts have also shown vulnerability when droughts occurred in spring especially at sites where long-term growth is not significantly correlated with climatic factors. This improved understanding of the role of drought seasonality and climate sensitivity of sites is key to better predict trajectories of post-drought growth recovery in response to the drier climate projected for Europe.}, language = {en} } @inproceedings{MunkPfriem2022, author = {Munk, Christoph and Pfriem, Alexander}, title = {Influence of residual oxygen content during thermal modification process on mass loss, brightness colour and dynamic Young´s modulus of Fagus sylvatica (L.)}, series = {18th Annual Meeting of the Northern European Network for Wood Science and Engineering, 21-22 September 2022, G{\"o}ttingen, Germany}, booktitle = {18th Annual Meeting of the Northern European Network for Wood Science and Engineering, 21-22 September 2022, G{\"o}ttingen, Germany}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-3582}, pages = {1 -- 3}, year = {2022}, abstract = {The thermal modification of wood is considered to be an environmentally friendly and cost-effective treatment process, which has been able to establish itself in many areas of application due to its positive effect on a whole range of different material properties through a wide variety of process designs. In addition to heat transfer and pressure, closed and open systems differ primarily in the choice of treatment atmosphere mainly used to prevent combustion (Sandberg et al. 2021). Although many studies in recent years have investigated influencing process parameters such as temperature, pressure or treatment duration, there exists a knowledge gap regarding the influence of the treatment atmosphere or its behaviour during the treatment process (Candelier et al. 2016). Therefore, this study aims to analyse different oxygen-nitrogen concentrations in the treatment atmosphere at different residual oxygen levels during the process duration and their influence on different property parameters of Fagus sylvatica (L.).}, language = {en} } @inproceedings{MunkClauderPfriem2019, author = {Munk, Christoph and Clauder, Lothar and Pfriem, Alexander}, title = {Sound absorption coefficient of thermally modified and unmodified wood species measured in an impedance tube}, series = {Northern European Network for Wood Science and Engineering (WSE) - 15th Annual Meeting 2019}, booktitle = {Northern European Network for Wood Science and Engineering (WSE) - 15th Annual Meeting 2019}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2890}, year = {2019}, abstract = {Different parts of the guitar body are made of certain wood species, selected by their specific properties. The sound board, which is mainly made of spruce or cedar, transfers the vibration of the strings to the resonance body by means of the bridge. The sides and the back of the guitar rather reflect the sound of the acoustic vibrations and are predominantly made of tropical hardwoods like palisander, mahogany or ebony species. These species have limited availability and are listed on the CITES Annex I and II. To substitute tropical wood species, thermally modified European wood species with improved acoustic properties and dimensional stability may be used. Although the acoustic reflection of the sides and the back parts of a guitar body is an important property, there is not much knowledge about this reflection behaviour of wood. A few studies like the work of Hong (1989), Kang (2010) or Smardzewski et al. (2013) investigated the sound absorption properties of unmodified wood. Subsequently this study considers the sound absorption coefficients of unmodified and thermally modified European wood species in comparison to an unmodified tropical wood species.}, language = {en} } @article{deMiguelDiezTolosanaEstebanPurfuerstetal.2021, author = {de Miguel-D{\´i}ez, Felipe and Tolosana Esteban, Eduardo and Purf{\"u}rst, Thomas and Cremer, Tobias}, title = {Analysis of the Influence That Parameters Crookedness and Taper Have on Stack Volume by Using a 3D-Simulation Model of Wood Stacks}, series = {Forests}, volume = {12}, journal = {Forests}, number = {2}, publisher = {MDPI}, issn = {1999-4907}, doi = {10.3390/f12020238}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2527}, pages = {10}, year = {2021}, abstract = {The influence that parameters crookedness and taper have on the stack volume was analyzed by using a 3D-simulation model in this study. To do so, log length, diameters at the midpoint and both ends, crookedness, bark thickness, taper and ovality were measured in 1000 logs of Scots pine. From this database, several data sets with different proportions of crooked and tapered logs in stack as well as with different degrees of taper and crookedness were created and taken as basis to simulate the stacks and carry out the analysis. The results show how the variation of these parameters influences the stack volume and provide their volume variation grades. These rates of variation were compared with measurement guidelines of some countries and previous research works. In conclusion, the parameters crookedness and taper influence the stack volume to a considerable extent. Specifically, the stack volume is increased as the crookedness degree or the proportion of crooked logs increases. In contrast, the stack volume is reduced as the taper degree or the proportion of tapered logs increases. Furthermore, the results demonstrate the capability of this simulation model to provide accurate results which can serve as a basis for future studies.}, language = {en} } @article{TakovPilarskaLindeetal.2021, author = {Takov, Danail and Pilarska, Daniela and Linde, Andreas and Barta, Marek}, title = {Infectious and parasitic diseases of phytophagous insect pests in the context of extreme environmental conditions}, series = {Central European Forestry Journal}, volume = {67}, journal = {Central European Forestry Journal}, number = {2}, publisher = {Sciendo}, issn = {2454-0358}, doi = {10.2478/forj-2020-0018}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2541}, pages = {72 -- 84}, year = {2021}, abstract = {The density of phytophagous insect pest populations is related (directly and indirectly) to several groups of factors that can be broadly divided into: abiotic, biotic and anthropogenic. Each extreme in the abiotic environment at a macro-level leads to a series of consecutive extremes in the biotic environment, which eventually results in micro-level responses in the individual organisms. The manifestation of factors acts in aggregate or in a sequence, creating a chain of processes around us. Insects very efficiently use the abundance of nutritional resources, resulting in a tremendous increase in their population density, and triggering control mechanisms through the emergence of parasitic and pathogenic infections (viruses, bacteria, fungi, microsporidia, protozoa and nematodes). The development of entomopathogenic infections in host populations is directly dependent on the characteristics of both the antagonist and the insect. It is associated with the lifestyle and life cycle of the insect, with features encoded in the mechanism of pathogen action, and limited by the pathogen's virulence and pathogenicity.}, language = {en} } @article{GillichMichlerStolteretal.2021, author = {Gillich, Benjamin and Michler, Frank-Uwe and Stolter, Caroline and Rieger, Siegfried}, title = {Differences in social-space-time behaviour of two red deer herds (Cervus elaphus)}, series = {acta ethologica}, volume = {24}, journal = {acta ethologica}, number = {3}, publisher = {Springer Nature}, issn = {0873-9749}, doi = {10.1007/s10211-021-00375-w}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-1962}, pages = {185 -- 195}, year = {2021}, abstract = {Social-space-time-behaviour has developed very differently (e.g. a, loner, a herd, a pack) in the animal kingdom and depends on many different factors, like food availability, competition, predator avoidance or disturbances. It is known, that red deer are differently distributed in human disturbed areas compared to areas with less anthropogenic influences. But knowledge about the potential influence of human presence on social associations and interactions is rare, albeit differences may result in changing impacts on the environment, such as habitat utilization and feeding damage. Therefore, we investigated differences in the space use and social association of red deer. We studied two radio-collared herds of non-migratory populations in two study areas, which were comparable in landscape structure and vegetation structure, but differed in accessibility for visitors and the extent of their presence. Between the two study sites we compared the home range size, the differences in the extent of home range overlap within each study site and the space-time association (Jacobs Index) of individuals. Additionally, we present data on seasonal variations of home range sizes and social association all year round. In order to compare human activity in the study sites, we used the data from our long-term camera trap monitoring. The herd in the area with more human activity had significantly smaller home ranges and had greater year-round social associations in almost all seasons, except summer. We assume that smaller home ranges and higher association between animals may result in a higher feeding pressure on plants and a patchier utilization in areas with higher disturbances.}, language = {en} } @article{SchmelzleBrunsBeckmannetal.2021, author = {Schmelzle, Sebastian and Bruns, Stefan and Beckmann, Felix and Moosmann, Julian and Lautner, Silke}, title = {Using In Situ Synchrotron-Radiation-Based Microtomography to Investigate 3D Structure-Dependent Material Properties of Tension Wood}, series = {Advanced Engineering Materials}, volume = {23}, journal = {Advanced Engineering Materials}, number = {11}, publisher = {Wiley}, issn = {1438-1656}, doi = {10.1002/adem.202100235}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-1925}, pages = {1 -- 11}, year = {2021}, abstract = {Synchrotron-radiation-based microtomography enables the 3D analysis of biological samples in situ beyond simple visualization, providing accurate measurements and recording of temporal data. The microtomography end station at P05 (PETRA III, Hamburg, Germany), operated by the Helmholtz Zentrum Hereon, can accommodate complex sample environments such as a load frame for mechanical testing. Herein, the strain analysis of a volumetric time series dataset of small hardwood samples is presented. For this in situ mechanical testing, the load frame is operated in tensile mode, and the biogenic material samples are subdivided into those specialized for tensile forces and those of regular anatomical structure. Digital volume correlation analysis allows for the prediction of strain development at any position in the sample. The tissue specialized for tensile strength can align dislocations formed under tension such that the deformation is stronger and more ordered. The results show how high-resolution imaging of sequential loading and the subsequent localization of strain can reveal functional morphological relationships. These methods can be extended to other biological materials and may prove to be extremely relevant for the analyses of fibrous and/or layered composite materials.}, language = {en} } @article{WinklerHaaseSchwarzetal.2021, author = {Winkler, Christoph and Haase, Stefan and Schwarz, Ulrich and Jahreis, Markus}, title = {Piezoresistive bond lines for timber construction monitoring—experimental scale-up}, series = {Wood Science and Technology}, volume = {55}, journal = {Wood Science and Technology}, number = {4}, publisher = {Springer Nature}, issn = {0043-7719}, doi = {10.1007/s00226-021-01305-6}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-1959}, pages = {1379 -- 1400}, year = {2021}, abstract = {Several laboratory studies and experiments have demonstrated the usability of polymer films filled with electrically conductive filler as piezoresistive material. Applied to adhesives, the glue lines of wood products can achieve multifunctional—thus bonding and piezoresistive/strain sensing—properties. Based on critical load areas in timber constructions, upscaled test setups for simplified load situations were designed, especially with regard to a stress-free electrical contact. In a second step, another upscaling was done to small glulam beams. Based on an experimental test sequence, the piezoresistive reactions as well as the behaviour until failure were analysed. The results show in all cases that a piezoresistive reaction of the multifunctionally bonded specimens was measurable, giving a difference in the extent of relative change. Additionally, measured phenomena like inverse piezoresistive reactions, electrical resistance drift and the absence of a piezoresistive reaction were discussed, based on additional strain analysis by digital image correlation. A model of macroscopic and microscopic strains influencing the piezoresistive reaction of the electrically conductive bond line in wood was used to explain all experimental results. Finally, a first scale-up of piezoresistive bond lines from laboratory samples to glulam beams was possible and successful.}, language = {en} } @article{SchaeferJagerSchwarzetal.2021, author = {Sch{\"a}fer, Jesco and Jager, Christopher and Schwarz, Ulrich and Winkler, Christoph}, title = {Improving the usability of piezoresistive bond lines in wood by using impedance measurements}, series = {Wood Science and Technology}, volume = {55}, journal = {Wood Science and Technology}, number = {4}, publisher = {Springer Nature}, issn = {0043-7719}, doi = {10.1007/s00226-021-01311-8}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-1942}, pages = {937 -- 954}, year = {2021}, abstract = {Various studies on wood adhesives filled with conductive fillers for future application to structural monitoring showed a piezoresistive (resistance change with strain) response of the adhesive bond lines that is measurable under direct current. The results also showed a relatively high signal noise with low sensitivity. Using impedance spectroscopy as a measurement technique, the improvements in frequency-dependent piezoresistivity over DC (Direct Current) resistography of multifunctional bonded wood were studied. Beech specimens were bonded by one-component polyurethane prepolymer (1C-PUR) filled with carbon black and tested under shear load. The quality of the piezoresistive properties was described by calculating the signal-to-noise ratio (SNR) of the measured signal. A setup-specific frequency band with optimized SNR between 100 kHz and 1 MHz could be derived from the measurements. Several frequencies showed a signal with higher quality resulting in a higher SNR. Regardless of the variations in impedance spectra for all specimens, this frequency band provided several frequencies with improved signal quality. These frequencies give a more reliable signal with lower noise compared to the signal from DC resistography.}, language = {en} } @techreport{HebertLucasDroganLucasetal.2021, type = {Working Paper}, author = {Hebert, Saskia and Lucas-Drogan, Diana and Lucas, Eike and Schneider, Tatjana and Strauß, Anke}, title = {W{\"u}nschenswerte Wohnzuk{\"u}nfte: Herausforderungen, Chancen und Potentiale zur Erh{\"o}hung der strukturellen Resilienz in Elbe Valley}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2150}, pages = {1 -- 93}, year = {2021}, language = {de} } @article{AschenbrandMichler2021, author = {Aschenbrand, Erik and Michler, Thomas}, title = {Why Do UNESCO Biosphere Reserves Get Less Recognition than National Parks? A Landscape Research Perspective on Protected Area Narratives in Germany}, series = {Sustainability}, journal = {Sustainability}, publisher = {MDPI}, issn = {2071-1050}, doi = {10.3390/su132413647}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2166}, pages = {18}, year = {2021}, abstract = {This paper explores how landscape research can contribute to our understanding of why integrated protected area concepts like biosphere reserves get less recognition than national parks. In this regard, we analysed policy documents and online communication of biosphere reserves and national parks, conducted qualitative interviews with conservation professionals and volunteers as well as participant observation in order to identify and compare narratives that guide the communication and perception of both protected area categories. The results show how national parks offer a clear interpretation of space by building on landscape stereotypes and creating landscape legibility and experience-ability through touristification. National Parks also experience conflicts about proper management and combine a variety of goals, often including regional development. Nevertheless, their narrative is unambiguous and powerful. Biosphere reserves, on the other hand, have an image problem that is essentially due to the difficulty of communicating their objectives. They confront the difficult task of creating a vision that combines development and conservation while integrating contrarious landscape stereotypes. We argue for a fundamental engagement with protected area narratives, as this improves understanding of protected areas' transformative potential.}, language = {en} } @article{RederMundAlbertetal.2021, author = {Reder, Stefan and Mund, Jan-Peter and Albert, Nicole and Waßermann, Lilli and Miranda, Luis}, title = {Detection of Windthrown Tree Stems on UAV-Orthomosaics Using U-Net Convolutional Networks}, series = {Remote Sensing}, volume = {14}, journal = {Remote Sensing}, number = {1}, publisher = {MDPI}, issn = {2072-4292}, doi = {10.3390/rs14010075}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2213}, pages = {25}, year = {2021}, abstract = {The increasing number of severe storm events is threatening European forests. Besides the primary damages directly caused by storms, there are secondary damages such as bark beetle outbreaks and tertiary damages due to negative effects on the market. These subsequent damages can be minimized if a detailed overview of the affected area and the amount of damaged wood can be obtained quickly and included in the planning of clearance measures. The present work utilizes UAV-orthophotos and an adaptation of the U-Net architecture for the semantic segmentation and localization of windthrown stems. The network was pre-trained with generic datasets, randomly combining stems and background samples in a copy-paste augmentation, and afterwards trained with a specific dataset of a particular windthrow. The models pre-trained with generic datasets containing 10, 50 and 100 augmentations per annotated windthrown stems achieved F1-scores of 73.9\% (S1Mod10), 74.3\% (S1Mod50) and 75.6\% (S1Mod100), outperforming the baseline model (F1-score 72.6\%), which was not pre-trained. These results emphasize the applicability of the method to correctly identify windthrown trees and suggest the collection of training samples from other tree species and windthrow areas to improve the ability to generalize. Further enhancements of the network architecture are considered to improve the classification performance and to minimize the calculative costs.}, language = {en} }