@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{BerendtdeMiguelDiezWalloretal.2021, author = {Berendt, Ferr{\´e}ol and de Miguel-Diez, Felipe and Wallor, Evelyn and Blasko, Lubomir and Cremer, Tobias}, title = {Comparison of different approaches to estimate bark volume of industrial wood at disc and log scale}, series = {Scientific Reports}, volume = {11}, journal = {Scientific Reports}, publisher = {Springer Nature}, issn = {2045-2322}, doi = {10.1038/s41598-021-95188-z}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-1987}, pages = {8}, year = {2021}, abstract = {Within the wood supply chain, the measurement of roundwood plays a key role due to its high economic impact. While wood industry mainly processes the solid wood, the bark mostly remains as an industrial by-product. In Central Europe, it is common that the wood is sold over bark but that the price is calculated on a timber volume under bark. However, logs are often measured as stacks and, thus, the volume includes not only the solid wood content but also the bark portion. Mostly, the deduction factors used to estimate the solid wood content are based on bark thickness. The aim of this study was to compare the estimation of bark volume from scaling formulae with the real bark volume, obtained by xylometric technique. Moreover, the measurements were performed using logs under practice conditions and using discs under laboratory conditions. The mean bark volume was 6.9 dm3 and 26.4 cm3 for the Norway spruce logs and the Scots pine discs respectively. Whereas the results showed good performances regarding the root mean square error, the coefficient of determination (R2) and the mean absolute error for the volume estimation of the total volume of discs and logs (over bark), the performances were much lower for the bark volume estimations only.}, language = {en} } @article{BerendtWolfgrammCremer2021, author = {Berendt, Ferr{\´e}ol and Wolfgramm, Felix and Cremer, Tobias}, title = {Reliability of photo-optical measurements of log stack gross volume}, series = {Silva Fennica}, volume = {55}, journal = {Silva Fennica}, number = {3}, issn = {2242-4075}, doi = {10.14214/sf.10555}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2003}, pages = {1 -- 13}, year = {2021}, abstract = {In terms of assessing economic impact, one of the most important elements in the wood supply chain is the measurement of round wood. Besides the one-by-one measurement of logs, logs are often measured when stacked at the forest road. The gross stacked volume includes the volume of the wood, bark and airspace and is widely used for industrial wood assortments. The increasing international attention given to photo-optical measurement systems for portable devices is due to their simplicity of use and efficiency. The aim of this study was to compare the gross volumes of hardwood log stacks measured using one widespread photo-optical app with two manual section-wise volume estimations of log stacks based on the German framework agreement for timber trade (RVR). The manual volume estimations were done starting from the left (RVRleft) and right (RVRright) sides of the log stacks. The results showed an average deviation of the photo-optical gross volume estimation in comparison to the manual estimation of -2.09\% (RVRleft) and -3.66\% (RVRright) while the deviation between RVRleft and RVRright was +2.54\%. However, the log stack gross volume had a highly significant effect on the deviation and better accuracy with smaller deviation were reached for larger log stacks. Moreover, results indicated that the gross volume estimations of higher quality log stacks were closer for the three analyzed methods compared to estimations of poor-quality log stacks.}, language = {en} } @article{BerendtPegelBlaskoetal.2021, author = {Berendt, Ferr{\´e}ol and Pegel, Erik and Blasko, Lubomir and Cremer, Tobias}, title = {Bark proportion of Scots pine industrial wood}, series = {European Journal of Wood and Wood Products}, volume = {79}, journal = {European Journal of Wood and Wood Products}, number = {3}, publisher = {Springer Nature}, issn = {0018-3768}, doi = {10.1007/s00107-021-01657-7}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-1975}, pages = {749 -- 752}, year = {2021}, abstract = {Bark characteristics are not only used in the forest-wood supply chain, for example to calculate standing volumes, but also to transform wood volumes and masses. In this study, bark thickness, bark volume and bark mass were analyzed on the basis of 150 Scots pine discs, with a mean diameter of 13 cm. The mean double bark thickness was 3.02 mm, the mean bark volume proportion was 5.6\% and mean bark mass proportion was 3.3\%. Bark proportions were significantly affected by the log-specific variables 'diameter over bark', 'proportion of bark damage' and 'double bark thickness'.}, language = {en} } @techreport{CremerBerendtdeMiguelDiezetal.2020, type = {Working Paper}, author = {Cremer, Tobias and Berendt, Ferr{\´e}ol and de Miguel Diez, Felipe and Wolfgramm, Felix and Blasko, Lubomir}, title = {Accuracy of Photo-Optical Measurement of Wood Piles}, series = {Environmental Sciences Proceedings}, journal = {Environmental Sciences Proceedings}, number = {3(1)}, publisher = {MDPI}, issn = {2673-4931}, doi = {10.3390/IECF2020-08192}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2012}, pages = {4}, year = {2020}, abstract = {The accurate estimation of timber volume is of the utmost importance. For industrial timber, the volume is often estimated as stacked cubic meters. In addition to manual measurements, volume estimation is possible with photo-optical systems. Over 100 piles of industrial timber of broadleaved tree species were analyzed. In the study, a standard manual measurement method for the estimation of wood pile volumes was compared with a smartphone based photo-optical application for the determination of woodpile volume. Mean gross volume of the piles was approximately 56 m3 and mean width of piles was 9.43 m. A strong correlation was found between the manual measurements and the photo-optical measurement. However, volume estimation of large volume piles seems to perform better in comparison to piles with small volumes. Further research is needed to determine the effects of variables such as log quality or quality of pile on volume estimation accuracy.}, language = {en} } @inproceedings{BerendtPegelBlaskoetal.2020, author = {Berendt, Ferr{\´e}ol and Pegel, Erik and Blasko, Lubomir and Cremer, Tobias}, title = {Bark Characteristics of Scots Pine Logs}, series = {Environmental Sciences Proceedings}, booktitle = {Environmental Sciences Proceedings}, publisher = {MDPI}, issn = {2673-4931}, doi = {10.3390/IECF2020-08020}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-2040}, pages = {1}, year = {2020}, abstract = {The wood of Scots pine (Pinus sylvestris L.) shows...}, language = {en} } @article{AmponsemBensahAhiekporetal.2022, author = {Amponsem, Bright and Bensah, Edem Cudjoe and Ahiekpor, Julius Cudjoe and Cremer, Tobias and Herold, Nadine and Antwi, Edward and Mensah, Isaac and Narra, Satyanarayana and Boahen, Benjamin}, title = {Cleaner energy potential analysis for composite biomass residues from decentralized sawmills in Ghana- A case study for Oforikrom Municipality}, series = {Cleaner Engineering and Technology}, journal = {Cleaner Engineering and Technology}, number = {11}, publisher = {Elsevier}, issn = {2666-7908}, doi = {10.1016/j.clet.2022.100563}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-6154}, pages = {11}, year = {2022}, abstract = {The variation of wood species processed in sawmills in developing countries generates composite waste which presents treatment challenges due to a lack of understanding of their physicochemical characteristics for proper planning for clean energy generation. Most of the waste is discarded or burnt openly which releases harmful gases into the environment. This study investigated the physicochemical characteristics of mixed sawdust generated from five wood species generated at a Ghanaian sawmill in Oforikrom Municipality for improving waste treatment. The particle size distribution (PSD), bulk density, proximate and ultimate values, thermogravimetric analysis (TGA) and structural analysis were used to characterize the composite sawdust for briquetting and gasification purposes. It was found that the net heating value (17.46 MJ/kg), some proximate and ultimate values meet briquette standard but high percentages of ash (2.95\%), moisture (41.48\%) and the possibility of nitrogen oxides emissions were notable challenges. PSD resulted in different high fine fractions which are unsuitable for densification. The increase of sieving amplitudes at 30, 50 and 80 rpm generated an average increase in sieve efficiency of fines by 4.22\%. Mixing of fines (42.38-46.6\%) and optimum particle size (53.40-57.62\%) fractions was suggested as the best approach to enhance briquette density and durability. The FTIR spectra showed a range of peaks such as 1734.46 cm-1, 1620.48 cm-1, 1506.50 cm-1, 1462.02 cm-1, 1420.32 cm-1 etc. for functional groups identification. Composite sawdust spectra showed high absorbance with no shift of wavenumbers compared with temperate woods, however, it deviated massively when compared with industrial cellulose and organosolv lignin. TGA indicated that exact mixed wood pyrolysis temperatures, volatile and biochar fractions will always depend on sample compositions. The increase in heating rates yielded little significance to volatiles and char increments. Collection of clean sawdust and rooftop drying were recommended as a way of enhancing sawdust properties. Composite sawdust has a promising potential to support Ghana's activities for meeting the renewable energy generation targets. The understanding of these potential assessments is significant to boost the local municipality energy supply.}, language = {en} } @article{BashutskaCremer2020, author = {Bashutska, U. B. and Cremer, Tobias}, title = {Екологічне оцінювання деревини робінії звичайної та рекультивованих відвалів шахт як резервної території для її вирощування}, series = {Scientific Bulletin of UNFU}, volume = {30}, journal = {Scientific Bulletin of UNFU}, number = {3}, issn = {1994-7836}, doi = {10.36930/40300309}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-4433}, pages = {51 -- 59}, year = {2020}, abstract = {Раціональне користування природними ресурсами є необхідним для сталого розвитку. Потребою сьогодення є використання екологічної сировини, яка спричиняє мінімальний вплив на довкілля та здоров'я людини під час її виробництва, використання й утилізації. Проаналізовано екологічну цінність деревини робінії звичайної на підставі вивчення її застосування та ринків збуту у Німеччині. Відзначено подібність її деревини за хімічним складом і властивостями із деревиною тропічних видів дерев, а також можливість заготівлі екологічно сприйнятливими способами. Вивчено можливість вирощування цього інтродукованого виду рослин на рекультивованих породних відвалах за умови екологічного моніторингу. Опрацьовано інформацію про насадження робінії звичайної у північно-східній низовині Німеччини. Проаналізовано будову, властивості деревини робінії та її можливе використання. Розглянуто принципи сортування та відповідні критерії якості деревини робінії. Здійснено порівняння ринків робінії у Бранденбурзі (Німеччина) та Угорщині. Запропоновано заходи щодо збільшення використання робінії. Розглянуто порушені землі Малого Полісся, як резервні території отримання екологічної деревини робінії звичайної. Екологічно обґрунтованим є відведення для цього порушених добуванням вугілля територій у сприятливих лісорослинних районах. Фітомеліоративні властивості робінії звичайної роблять її перспективним видом для залісення новоутворених екотопів із широкою екологічною амплітудою в умовах Малого Полісся. Наявність насипних рекультиваційних ґрунтів є необхідною умовою для приживання та рівномірного росту і розвитку робінієвих культур в умовах породних відвалів шахт. Якість та продуктивність робінієвих насаджень залежать від фізико-хімічних властивостей шарів насипних ґрунтів та мікрокліматичних особливостей екотопів відвалів. Це зумовлює відмінності в рості й розвитку робінієвих насаджень, впливає на показники якості деревини робінії і зумовлює шляхи її можливого використання. Меліоративна функція робінієвих насаджень на післягірничих ландшафтах є особливо важливою у час зміни клімату. Продуктивна функція робінієвих насаджень на післягірничих ландшафтах дає підставу розглядати їх як додаткове джерело біологічно стійкої деревини.}, language = {mul} } @inproceedings{deMiguelDiezTolosanaEstebanCremer2021, author = {de Miguel-D{\´i}ez, Felipe and Tolosana-Esteban, Eduardo and Cremer, Tobias}, title = {3D-Simulation of Wood Stacks to Analyze the Influence of Log Properties on Stack Volume}, series = {Environmental Sciences Proceeding}, booktitle = {Environmental Sciences Proceeding}, number = {3(1)}, publisher = {MDPI}, issn = {2673-4931}, doi = {10.3390/IECF2020-08063}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-4452}, pages = {6}, year = {2021}, abstract = {The quantification of the solid wood content in a wood stack has been an object of investigation since the 18th century. Particularly, the log parameters exert a considerable influence on the volume of the stack, such as (1) the log midpoint diameter, (2) average bark thickness, (3) crookedness, and (4) log taper. Although many of these parameters have already been studied and some are already considered in many countries when measuring wood stacks, their influence has not been analyzed individually so far since a broad statistical database is needed and the data collection is very costly. Consequently, a 3D-simulation model was developed based on a cross-platform game engine. This model generates virtual wood stacks based on a data set of logs which are defined by the user. The simulation of a stack can be done in a few seconds only and each stack generated can be visualized once all iterations are done. The simulation results are the stacked cubic volume, solid wood cubic volume, and the respective conversion factors. The model, fed with both real data and user-defined data, allows for a detailed analysis of the effect of each parameter on the results, as the user can vary their values discretionary. To obtain the first results from real data, 1000 logs of Scots pine (Pinus sylvestris L.) were measured. The first simulations based on these data show reliable results and it is possible to quantify the influence of the proportion of crooked wood in a pile on the stack volume and the conversion factor. In addition, the results are highly in line with the real trials that have already been performed in parallel. A further scientific evaluation and statistical analysis will be done in a second study phase. However, the model already provides a reasonable tool that is easy to apply for the forest and wood industry in order to make the most accurate estimate possible of the solid wood content in a wood pile.}, language = {en} } @inproceedings{deMiguelDiezRederWalloretal.2021, author = {de Miguel-D{\´i}ez, Felipe and Reder, Stefan and Wallor, Evelyn and Bahr, Henrik and Mund, Jan-Peter and Cremer, Tobias}, title = {Long Range and High-Speed Personal Laser Scanning (PLS) and Simultaneous Localization and Mapping (SLAM) Technology in Roundwood Measurement}, series = {Proceedings of the SilviLaser Conference 2021}, booktitle = {Proceedings of the SilviLaser Conference 2021}, doi = {10.34726/wim.1929}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-4462}, pages = {3}, year = {2021}, language = {en} } @article{LitschelBerendtCremer2023, author = {Litschel, Johannes and Berendt, Ferr{\´e}ol and Cremer, Tobias}, title = {Holzbauquote in Berlin-Brandenburg steigern}, series = {Holz-Zentralblatt}, volume = {149}, journal = {Holz-Zentralblatt}, number = {35}, publisher = {DRW-Verlag Weinbrenner GmbH \& Co. KG}, issn = {0018-3792}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-7965}, pages = {1}, year = {2023}, abstract = {Das im Februar gestartete Forschungsvorhaben "Adapt-Wald-Holz" unter der Leitung der Hochschule f{\"u}r nachhaltige Entwicklung Eberswalde (HNEE) steht im Zeichen von Branchenvernetzung, regionaler Wertsch{\"o}pfung und Nachwuchsf{\"o}rderung. Ziel ist es, ein adaptives, d.h. anpassungsf{\"a}higes, Wald-Holz-Managementsystem f{\"u}r die Region Brandenburg-Berlin am Beispiel der Waldkiefer zu entwickeln.}, language = {de} } @inproceedings{CremerMartetschlaegerBartschetal.2023, author = {Cremer, Tobias and Martetschl{\"a}ger, Lea and Bartsch, Marco and Riethm{\"u}ller, Sina and Schnautz, Carmel and Gaiser, Thomas and Bloch, Ralf}, title = {Entwicklung ertragskundlicher und {\"o}kologischer Paramter in einem Brandenburger Alley Cropping System}, series = {Tagungsband 9. Forum Agroforstsysteme, 27. \& 28. September 2023}, booktitle = {Tagungsband 9. Forum Agroforstsysteme, 27. \& 28. September 2023}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-7980}, pages = {1}, year = {2023}, language = {de} } @article{PurfuerstdeMiguelDiezBerendtetal.2023, author = {Purf{\"u}rst, Thomas and de Miguel-D{\´i}ez, Felipe and Berendt, Ferr{\´e}ol and Engler, Benjamin and Cremer, Tobias}, title = {Comparison of wood stack volume determination between manual, photo-optical, iPad-LiDAR and handheld-LiDAR based measurement methods}, series = {iForest - Biogeosciences and Forestry}, volume = {16}, journal = {iForest - Biogeosciences and Forestry}, number = {4}, publisher = {Italian Society of Silviculture and Forest Ecology}, issn = {1971-7458}, doi = {10.3832/ifor4153-016}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-8062}, pages = {243 -- 252}, year = {2023}, abstract = {The measurement of roadside wood stacks in the forest still plays an important role in many forestry operations. Traditional manual measuring methods can be laborious, inaccurate and error-prone. Therefore, the issue is whether 2.5D or 3D optical remote sensing measuring methods provide more precise or detailed results and advantages in further data processing. This study examined and partly developed nine different manual, photo-optical, iPad®-LiDAR and handheld laser scanner-LiDAR-based wood stack measurement methods. Forty-seven wood stacks, ranging from 8.9 to 209.3 m3 (totalling approximately 2700 m3), were measured and compared using these nine methods. All the methods give volume estimations, and none can be seen to give the real or true wood stack gross volume. Surprisingly, the results varied significantly within and between the individual methods, with up to a 9\% mean relative deviation. The relative deviation is strongly dependent on the size of the wood stack. The 3D measurement methods using iPad® RGB and LiDAR recorded lower timber volumes than the other methods, in contrast to the method based on samples taken with handheld laser scanner-LiDAR, which overestimated the volume. Generally, optical- and laser-based surveying techniques could be more widely applied in measuring wood stacks in the future. However, such automatic wood stack gross volume determination approaches still face some challenges, regarding accuracy in the case of the 2.5D methods and the lack of automatisation in the case of 3D methods. Consequently, further research is required in the near future.}, language = {en} } @inproceedings{LitschelBerendtWelpetal.2023, author = {Litschel, Johannes and Berendt, Ferr{\´e}ol and Welp, Martin and Cremer, Tobias}, title = {Perspektiven von Schl{\"u}sselakteuren auf das Potenzial der Agroforstwirtschaft in Nordostdeutschland}, series = {Tagungsband 9. Forum Agroforstsysteme, 27. \& 28. September 2023}, booktitle = {Tagungsband 9. Forum Agroforstsysteme, 27. \& 28. September 2023}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-8040}, pages = {16 -- 17}, year = {2023}, language = {de} } @article{deMiguelDiezPurfuerstAcunaetal.2023, author = {de Miguel-D{\´i}ez, Felipe and Purf{\"u}rst, Thomas and Acuna, Mauricio and Tolosana-Esteban, Eduardo and Cremer, Tobias}, title = {Estimation of conversion factors for wood stacks in landings and their influencing parameters: a comprehensive literature review for America and Europe}, series = {Silva Fennica}, volume = {57}, journal = {Silva Fennica}, number = {1}, publisher = {The Finnish Society of Forest Science}, issn = {2242-4075}, doi = {10.14214/sf.22018}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-6459}, pages = {47}, year = {2023}, abstract = {In commercial transaction of stacked roundwood, the estimation of the stack net volume plays a key role. One generalized method to determine the net volume is using conversion factors that relate the gross and net volumes. In this literature review the developed methods to estimate the conversion factors as well as their influencing parameters were analyzed based on 153 references from America and Europe. According to the results, 48 different methods (including their variants) for estimating the conversion factors were developed. The newest methods enabled their accurate determination inexpensively, e.g., photo-optical methods or 3D simulation models. The analyzed references revealed that 30 parameters influence the conversion factors. Based on this comprehensive review, each stakeholder involved in the roundwood supply chain can know which method is used for estimating the conversion factors in the analyzed territories and which influencing parameters should be considered when purchasing roundwood in order to accurately assess the solid wood content in the stacks.}, language = {en} } @article{WenigReppeHorbeltetal.2023, author = {Wenig, Charlett and Reppe, Friedrich and Horbelt, Nils and Spener, Jaromir and Berendt, Ferr{\´e}ol and Cremer, Tobias and Frey, Marion and Burgert, Ingo and Eder, Michaela}, title = {Adhesives free bark panels: An alternative application for a waste material}, series = {PloS one}, volume = {18}, journal = {PloS one}, number = {1}, publisher = {Public Library of Science (PLoS)}, doi = {10.1371/journal.pone.0280721}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-6104}, year = {2023}, abstract = {The proportion of bark in tree trunks is in the range of ~ 10-20\%. This large amount of material is currently mainly considered as a by- or even waste-product by the timber processing industry. Recently, efforts towards the use of bark have been made, e.g. as a raw material to harvest different chemical compounds or as an additive for wood particle boards. Our motivation for this work was to keep the bark in an almost natural state and explore alternative processes and applications for use. The traditional method of de-barking tree trunks by peeling was used to harvest large bark pieces. Two pieces of peeled bark were placed crosswise, with the rhytidom side (outer bark) facing each other. After different conditioning steps, bark pieces were hot pressed to panels without adding adhesives. These experiments on bark samples of different Central European tree species suggest that production of panels with species dependent properties is possible and feasible. This is a step towards producing sustainable panels by using a natural waste material, while retaining its beneficial structure and its natural chemical composition.}, language = {en} } @misc{WenigReppeHorbeltetal.2023, author = {Wenig, Charlett and Reppe, Friedrich and Horbelt, Nils and Spener, Jaromir and Berendt, Ferr{\´e}ol and Cremer, Tobias and Burgert, Ingo and Eder, Michaela}, title = {Adhesives free bark panels: an alternative application for a waste material}, doi = {10.17617/3.AZRWF3}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-6118}, year = {2023}, language = {en} } @article{Cremer2020, author = {Cremer, Tobias}, title = {Zu Besuch bei den Nasenbeißern}, series = {Deutsches Bienen-Journal}, volume = {28}, journal = {Deutsches Bienen-Journal}, number = {3}, publisher = {Deutscher Bauernverlag GmbH}, issn = {0943-2914}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-6012}, pages = {66 -- 68}, year = {2020}, language = {de} } @article{CremerBlasko2017, author = {Cremer, Tobias and Blasko, Lubomir}, title = {Analyse der fotooptischen Vermessung von Kiefernstamm- und -industrieholz im Vergleich zum Sektionsraumaß}, series = {Allgemeine Forst- und Jagdzeitung}, volume = {188}, journal = {Allgemeine Forst- und Jagdzeitung}, number = {7/8}, publisher = {J. D. Sauerl{\"a}nder}, issn = {0002-5852}, doi = {10.23765/afjz0002008}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-4551}, pages = {127 -- 139}, year = {2017}, language = {de} } @article{deMiguelDiezRederWalloretal.2022, author = {de Miguel-D{\´i}ez, Felipe and Reder, Stefan and Wallor, Evelyn and Bahr, Henrik and Blasko, Lubomir and Mund, Jan-Peter and Cremer, Tobias}, title = {Further application of using a personal laser scanner and simultaneous localization and mapping technology to estimate the log's volume and its comparison with traditional methods}, series = {International Journal of Applied Earth Observation and Geoinformation}, journal = {International Journal of Applied Earth Observation and Geoinformation}, number = {109}, publisher = {Elsevier}, issn = {1872-826X}, doi = {10.1016/j.jag.2022.102779}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-4496}, pages = {7}, year = {2022}, abstract = {The aim of this study was the development of a methodical processing line for estimating the log's volume from scanning logs using a long-range high-speed personal laser scanner (PLS) GeoSLAM ZEB HORIZON and simultaneous localization and mapping (SLAM) technology in an open-source software framework of Cloud Compare. Additionally, the accuracy and precision of using PLS and the suggested method when measuring roundwood volume was examined compared to measurements made using a xylometer and estimations obtained from applying the formulae of Huber, Smalian and Newton. For this purpose, several parameters were measured in 50 logs of Norway spruce with an average length of 2.53 m and a mean diameter of 19.97 cm. Afterwards, the volume of these 50 logs was measured with a xylometer. The results of these measurements served as reference values. The same 50 logs were subsequently scanned with the PLS. The scans were converted into point clouds and were analyzed in Cloud Compare to estimate the volume of the scanned logs. Next, the root mean square error (RMSE) and the mean bias error (MBE) as well as their relative values were calculated for the volumes determined in Cloud Compare and estimated with the above mentioned formulae. The calculated RMSE (and relative RMSE) determined a deviation of the logs' volumes estimated in Cloud Compare from the xylometric volumes of 2.88 dm3 (3.54\%) whereas the deviations of the log's volumes calculated applying the formulae of Huber, Smalian and Newton from the xylometric volumes were respectively 9.63 dm3 (11.83\%), 10.33 dm3 (12.69\%) and 4.69 dm3 (5.76\%). The calculated MBE (and relative MBE) showed that the estimated volumes in Cloud Compare and those using the formulae were overestimated, with the lowest overestimation of 0.10 dm3 (0.12\%) in Cloud Compare and the highest, 5.50 dm3 (6.75\%), using the Smalian formula. Therefore, it can be stated that results of suggested methodical processing line came closest to the logs' volumes obtained with the xylometer, i.e., they were more accurate and precise compared to the conventionally formulae for log's volume estimation. The implementation of this method has the potential filling a gap towards a wall-to-wall complete digitization of the roundwood commercialization and ensure transparency and acceptance between the stakeholders involved in the wood supply chain.}, language = {en} } @article{deMiguelDiezPettenkoferWalloretal.2022, author = {de Miguel-D{\´i}ez, Felipe and Pettenkofer, Tim and Wallor, Evelyn and Tolosana-Esteban, Eduardo and Purf{\"u}rst, Thomas and Cremer, Tobias}, title = {Influence of log and stack parameters on the conversion factors for Norway Spruce wood stacks using a 3D simulation model}, series = {International Journal of Forest Engineering}, volume = {33}, journal = {International Journal of Forest Engineering}, number = {2}, publisher = {Taylor \& Francis}, issn = {1494-2119}, doi = {10.1080/14942119.2022.2038023}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-4482}, pages = {119 -- 128}, year = {2022}, abstract = {One method for estimating the solid wood content in a stack involves using conversion factors and multiplying these by the measured gross volume. The conversion factors can vary depending on several log and stack parameters. The aim of this study was to analyze eleven parameters using a 3D simulation model based on 541 measured logs of Norway spruce. To this end, 50 data sets were created from measured logs, where the parameters of interest in this study (e.g., length, crookedness, taper …) were classified according to different ranges. After that, 64 runs of simulations were carried out. In each simulation run, 150 stacks were modeled. The simulation results were compared with previous studies and with the measurement guidelines of several countries. This analysis revealed that the parameters midpoint diameter, length, crookedness, delimbing quality and the proportion of moderately and highly crooked logs in a stack have a considerable influence on the conversion factors. Taper, proportion of butt logs in a stack and stack height have a modest effect as do the proportion of tapered and crooked logs for low and high taper and low crookedness. In contrast, ovality and the proportion of logs stacked in opposite directions have a marginal influence on the conversion factors. Based on findings from these analyses, the current measurement guidelines of different countries can now be adapted to achieve a higher degree of accuracy.}, language = {en} } @article{BerendtBajalanWenigetal.2023, author = {Berendt, Ferr{\´e}ol and Bajalan, Iman and Wenig, Charlett and Hinds, Charlotte and Blaško, Ľubom{\´i}r and Cremer, Tobias}, title = {Estimation of Scots pine bark biomass delivered to the wood industry in Northern Germany}, series = {Central European Forestry Journal}, volume = {69}, journal = {Central European Forestry Journal}, number = {2}, publisher = {Sciendo}, issn = {2454-0358}, doi = {10.2478/forj-2022-0019}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-6126}, pages = {89 -- 97}, year = {2023}, abstract = {Scots pine (Pinus sylvestris L.) is the most widely distributed pine species in the world. In Germany, as in many other European countries, it is a very important species both culturally and economically. Few studies have focused on bark volumes being delivered to the wood industry together with the roundwood, being potentially a valuable resource for material or energetic utilization. Therefore, logs from six different forest sites were collected and bark variables including double bark thickness (DBT) in three different categories, diameter, and bark damage (as a degree of miss-DBT) in three different categories, diameter, and bark damage (as a degree of miss-ing bark) were measured and analyzed in order to model bark volume (Vbark) and bark mass (Mbark). The correlation analysis using Pearson's method showed that the highest correlation coefficients were observed from the correla-tion between DBT and Vbark, as well as between DBT and Mbark. Also, results demonstrated that with DBT greater than 20 mm, the percentage of Vbark exceeded 20\%. Finally, different linear regression models were recommended to predict Vbark and Mbark based on the other variables. The results of this study can be used in different wood industries in order to predict bark volume and bark mass of e.g. truckloads or roundwood stacks.}, language = {en} } @article{GrimpeLuckeLorenzetal.2022, author = {Grimpe, J. and Lucke, S. and Lorenz, T. and Bloch, Ralf and Cremer, Tobias}, title = {Agroforst auf trockenen B{\"o}den. On-Farm-Versuch in Brandenburg}, series = {LUMBRICO: konservierender {\"o}kologischer Landbau}, journal = {LUMBRICO: konservierender {\"o}kologischer Landbau}, number = {11}, publisher = {Emminger \& Partner GmbH}, address = {Berlin}, issn = {1432-9387}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-6441}, pages = {41 -- 45}, year = {2022}, abstract = {Die Anlage von Agroforstsystemen (AFS) wird seit einigen Jahren, auch in Deutschland, als Methode der Aufbauenden Landwirtschaft angesehen. Die Hochschule f{\"u}r nachhaltige Entwicklung Eberswalde (HNEE) erprobt diese Bewirtschaftungsform unter realen Bedingungen, im laufenden Gesch{\"a}ft eines Landwirtschaftsbetriebes - in einem sogenannten „Reallabor".}, language = {de} } @article{LitschelBerendtCremeretal.2022, author = {Litschel, Johannes and Berendt, Ferr{\´e}ol and Cremer, Tobias and Welp, Martin}, title = {Mit regenerativen Materialien zur Brandenburger Bauwende?}, series = {Holz-Zentralblatt}, volume = {148}, journal = {Holz-Zentralblatt}, number = {36}, publisher = {DRW-Verlag Weinbrenner GmbH \& Co. KG}, issn = {0018-3792}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-6213}, pages = {608 -- 608}, year = {2022}, abstract = {Gemeinsam mit zahlreichen Akteuren aus Berlin und Brandenburg untersucht die Hochschule f{\"u}r nachhaltige Entwicklung Eberswalde (HNEE) in einem breit angelegten Modellvorhaben die Potenziale regenerativer Materialien f{\"u}r die Baubranche.}, language = {de} } @article{MetzgerCremerBlochetal.2022, author = {Metzger, Lukas and Cremer, Tobias and Bloch, Ralf and Lorenz, Tommy}, title = {Innovative Lehre zur F{\"o}rderung der Agroforstwirtschaf}, series = {B\&B Agrar}, volume = {75}, journal = {B\&B Agrar}, number = {2}, publisher = {Bundesanstalt f{\"u}r Landwirtschaft und Ern{\"a}hrung (BLE)}, issn = {1618-9833}, pages = {18 -- 19}, year = {2022}, abstract = {Die Hochschule f{\"u}r nachhaltige Entwicklung Eberswalde (HNEE) geht neue Wege: Im Zusammenspiel aus Lehre, Forschung und Praxis soll die Agroforstwirtschaft in Deutschland gef{\"o}rdert werden. Ein Reallabor erm{\"o}glicht Studierenden dabei, teamorientiert und partizipativ zu lernen.}, language = {de} } @article{deMiguelDiezGuiguePettenkoferetal.2022, author = {de Miguel-D{\´i}ez, Felipe and Guigue, Phillippe and Pettenkofer, Tim and Tolosana-Esteban, Eduardo and Purf{\"u}rst, Thomas and Cremer, Tobias}, title = {Development and evaluation of a novel 3D simulation software for modelling wood stacks}, series = {PLoS ONE}, journal = {PLoS ONE}, number = {17(3)}, issn = {1932-6203}, doi = {10.1371/journal.pone.0264414}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-4472}, pages = {17}, year = {2022}, abstract = {Assessing the solid wood content is crucial when acquiring stacked roundwood. A frequently used method for this is to multiply determined conversion factors by the measured gross volume. However, the conversion factors are influenced by several log and stack parameters. Although these parameters have been identified and studied, their individual influence has not yet been analyzed using a broad statistical basis. This is due to the considerable financial resources that the data collection entails. To overcome this shortcoming, a 3D-simulation model was developed. It generates virtual wood stacks of randomized composition based on one individual data set of logs, which may be real or defined by the user. In this study, the development and evaluation of the simulation model are presented. The model was evaluated by conducting a sensitivity and a quantitative analysis of the simulation outcomes based on real measurements of 405 logs of Norway spruce and 20 stacks constituted with these. The results of the simulation outcomes revealed a small overestimation of the net volume of real stacks: by 1.2\% for net volume over bark and by 3.2\% for net volume under bark. Furthermore, according to the calculated mean bias error (MBE), the model underestimates the gross volume by 0.02\%. In addition, the results of the sensitivity analysis confirmed the capability of the model to adequately consider variations in the input parameters and to provide reliable outcomes.}, language = {en} } @article{GoergensMundCremeretal.2020, author = {G{\"o}rgens, Eric Bastos and Mund, Jan-Peter and Cremer, Tobias and de Conto, Tiago and Krause, Stuart and Valbuena, Ruben and Estraviz Rodriguez, Luiz Carlos}, title = {Automated operational logging plan considering multi-criteria optimization}, series = {Computers and Electronics in Agriculture}, journal = {Computers and Electronics in Agriculture}, number = {170}, publisher = {Elsevier}, issn = {0168-1699}, doi = {10.1016/j.compag.2020.105253}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-4423}, year = {2020}, abstract = {Multiple goals should be considered while planning and executing forest management. This study proposes a new multidimensional framework for a precision forestry approach assisted by airborne laser scanning data (ALS). Therefore, successful management operations become a key element in the process of promoting protection through sustainable development. Thirteen relevant variables were derived from ALS data, such as: canopy height, terrain topography, relative vegetation density, forest gaps, slope restrictions, skidder restrictions, load truck restrictions, topographic wetness, flow accumulation, horizontal distance to drainage, vertical elevation from drainage, stream and headspring restrictions. Four different scenarios for the management plan optimization were studied: shortest distance, forest conservation, soil conservation and all combined. Results showed that the detailed forest information from ALS point clouds is useful to indicate regions not suitable for forest operations. Failure to properly consider the different factors involved may result in inadequate infrastructures, lower operational performance and constant re-planning requirements.}, language = {en} } @article{BlaškoVyhnalikovaCremer2020, author = {Blaško, Luboš and Vyhn{\´a}likov{\´a}, Zuzana and Cremer, Tobias}, title = {Fotooptick{\´e} merania objemu dreva na zvyšovanie efekt{\´i}vnosti logistick{\´e}ho reťazca na Št{\´a}tnej lesnej spr{\´a}ve Chorin (NSR)}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-4441}, pages = {18 -- 28}, year = {2020}, language = {mul} } @article{WilmsDuppelCremeretal.2021, author = {Wilms, Florian and Duppel, Nils and Cremer, Tobias and Berendt, Ferr{\´e}ol}, title = {Bark Thickness and Heights of the Bark Transition Area of Scots Pine}, series = {Forests}, journal = {Forests}, number = {12(10)}, publisher = {MDPI}, issn = {1999-4907}, doi = {10.3390/f12101386}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-4330}, pages = {1 -- 12}, year = {2021}, abstract = {The estimation of forest biomass is gaining interest not only for calculating harvesting volumes but also for carbon storage estimation. However, bark (and carbon) compounds are not distributed equally along the stem. Particularly when looking at Scots pine, a radical change in the structure of the bark along the stem can be noted. At the bark transition area, the bark changes from thick and rough to thin and smooth. The aim of our study was (1) to analyze the height of the bark transition area where the bark structure changes and (2) to analyze the effect of cardinal direction on the bark thickness. Regression analyses and forward selection were performed including measured tree height, DBH, bark thickness, crown base height and upper and lower heights of the bark transition areas of 375 trees. While the cardinal direction had no effect on bark thickness, DBH was found to have a significant effect on the heights of the bark transition areas, with stand density and tree height having a minor additional effect. These variables can be used to estimate timber volume (without bark) with higher accuracy and to predict the carbon storage potential of forest biomass according to different tree compartments and compounds.}, language = {en} } @article{LitschelBerendtWagneretal.2023, author = {Litschel, Johannes and Berendt, Ferr{\´e}ol and Wagner, Hanna and Heidenreich, Simon and Bauer, David and Welp, Martin and Cremer, Tobias}, title = {Key Actors' Perspectives on Agroforestry's Potential in North Eastern Germany}, series = {Land}, volume = {12}, journal = {Land}, number = {2}, publisher = {MDPI}, issn = {2073-445X}, doi = {10.3390/land12020458}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-4003}, pages = {1 -- 19}, year = {2023}, abstract = {As a land use management system, agroforestry has environmental, economic and societal benefits over conventional agriculture or forestry. Important benefits of combining tree growth with agricultural crops and/or forage production systems include higher biodiversity through more diverse habitats, the control of runoff and soil erosion, the augmentation of soil water availability, the creation of microclimates, carbon sequestration and provision of a more diverse farm economy. As the climate changes, north eastern Germany is likely to be particularly prone to severe effects from droughts and wind erosion in the future. However, the area of land under agroforestry makes up less than 2\% of the total agricultural area in Germany. Through qualitative interviews with key actors, this study analyzed the benefits of, potentials for and barriers to implementing agroforestry systems in the federal state of Brandenburg. Results showed that agroforestry systems have significant potential in relation to several benefits, particularly the mitigation of soil erosion and stabilization of microclimate regimes. Additionally, agroforestry has the potential to provide wood for energy production or material uses. Although a small but highly innovative and interlinked community exists, administrative barriers and high start-up costs currently hamper the transition from conventional agriculture to agroforestry systems.}, language = {en} } @article{CremerMajorAgyemanetal.2023, author = {Cremer, Tobias and Major, Friederike and Agyeman, Yaw Boakye and Rottig, Franziska}, title = {Biosph{\"a}renreservat optimieren}, series = {E+Z Entwicklung und Zusammenarbeit}, journal = {E+Z Entwicklung und Zusammenarbeit}, number = {8}, publisher = {Fazit Communication GmbH}, issn = {2366-7249}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-6799}, pages = {29 -- 30}, year = {2023}, abstract = {Deutsche und ghanaische Forscher*innen arbeiten zusammen, um die lokale Bev{\"o}lkerung in die Entwicklung eines UNESCO-Biosph{\"a}renreservats einzubeziehen. Ziel ist es, Forschungsl{\"u}cken zu schließen, um den Gemeinden konkrete Entwicklungsm{\"o}glichkeiten aufzuzeigen.}, language = {de} } @inproceedings{BlochCremerWartenbergetal.2022, author = {Bloch, Ralf and Cremer, Tobias and Wartenberg, Ariani and Molitor, Heike and Lorenz, Tommy}, title = {Innovative Lehr- und Lernform zur Implementierung eines Agroforstsystems - 4 Jahre Erfahrungen aus dem Reallabor „Ackerbaum"}, series = {Nachhaltig wirken: Reallabore in der Transformation}, booktitle = {Nachhaltig wirken: Reallabore in der Transformation}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-6736}, year = {2022}, abstract = {Das Wahlpflichtmodul Agroforst wird an der Hochschule f{\"u}r nachhaltige Entwicklung Eberswalde als innovative Lehr- und Lernform, kurz ILL, von Studierenden f{\"u}r Studierende durchgef{\"u}hrt. Im Sinne einer offenen Lehrwerkstatt ist das Modul interdisziplin{\"a}r ausgerichtet und f{\"u}r Bachelor- und Masterstudierende verschiedener Studieng{\"a}nge anw{\"a}hlbar. Die studentischen Tutor:innen werden von zwei Professoren der Hochschule begleitet. Angeschlossen an das Modul ist neben Vortr{\"a}gen und Exkursionen die Forschung im Reallabor „Ackerbaum" wodurch transdisziplin{\"a}res Arbeiten vermittelt wird. Dabei handelt es sich um eine knapp 10 Hektar große Ackerfl{\"a}che im L{\"o}wenberger Land, n{\"o}rdlich von Berlin. Auf dem die Studierenden sowohl B{\"a}ume pflanzen, als auch deren Wachstum und ihre Effekte auf das Mikroklima und die Ackerkulturen, sowie den Boden beobachten und dokumentieren. Wissenschaftliche Unterst{\"u}tzung erh{\"a}lt das Projekt durch Wissenschaftler:innen der Universit{\"a}t Bonn und dem ZALF e.V., die gemeinsam im „Agrarsysteme der Zukunft-Projekt - DAKIS" (https://adz- dakis.com/ueber-dakis/) daran arbeiten, die Auswirkungen von Agroforstsystemen auf {\"O}kosystemleistungen und Biodiversit{\"a}t zu erfassen und zu bewerten. In den vergangenen 4 Jahren 2017 - 2021 wurden von den Studierenden {\"u}ber 50 Projektberichte erstellt. Diese wurden aufw{\"a}ndig analysiert und mittels vorher definierter Indikatoren klassifiziert. Um weitere R{\"u}ckschl{\"u}sse auf die Qualit{\"a}t der studentischen Lehre ziehen zu k{\"o}nnen, wurde in Umfragen die Meinung und Zufriedenheit der Studierenden als auch der Tutor:innen anonym abgefragt und ausgewertet. Die Daten werden aktuell ausgewertet und die Analyse kann auf der Tagung vorgestellt werden.}, language = {de} } @article{LorenzGersterWodzinowskietal.2022, author = {Lorenz, Tommy and Gerster, Lea and Wodzinowski, Dustin Elias and Wartenberg, Ariani and Martetschl{\"a}ger, Lea and Molitor, Heike and Cremer, Tobias and Bloch, Ralf}, title = {Innovative Teaching and Learning Formats for the Implementation of Agroforestry Systems—An Impact Analysis after Five Years of Experience with the Real-World Laboratory "Ackerbaum"}, series = {Forests}, volume = {13}, journal = {Forests}, number = {7}, publisher = {MDPI}, issn = {1999-4907}, doi = {10.3390/f13071064}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-3092}, pages = {14}, year = {2022}, abstract = {Since 2017, the Eberswalde University for Sustainable Development (HNEE) offers transformative learning modules in their curricula, which are called ITL—Innovative Teaching and Learning formats. Student tutors change into the role of teachers and organize lectures, excursions, and assignments at the Real-World Laboratory "Ackerbaum"—an agroforestry system in the federal state of Brandenburg, Germany. Students can learn about agroforestry systems, participate in research, and take practical action. The examination of the module is a scientific report linked to the experimental area. In this study, an attempt was made to verify the quality and impact of teaching formats in the ITL via the analysis of 53 reports created by 170 students as well as surveys among participants. For this purpose, indicators were formulated that capture the quality of scientific methods and the contribution to higher education for sustainable development. Students and tutors appreciate the open working atmosphere and the possibility to actively participate in the course; many leave the module motivated. Some even move toward transformation in agriculture professionally as, e.g., consultants in the field of agroforestry. As a transformative institution, HNEE offers with ITL a rare opportunity for practical application, scientific methods, and transdisciplinary collaboration with different stakeholders to work on future models to change today's agriculture.}, language = {en} }