@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} } @article{HentschelMoellerWenningetal.2018, author = {Hentschel, Rainer and M{\"o}ller, Katrin and Wenning, Aline and Degenhardt, Annett and Schr{\"o}der, Jens}, title = {Importance of Ecological Variables in Explaining Population Dynamics of Three Important Pine Pest Insects}, series = {Frontiers in Plant Science}, journal = {Frontiers in Plant Science}, number = {9}, publisher = {Frontiers Media S.A.}, issn = {1664-462X}, doi = {10.3389/fpls.2018.01667}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-3285}, pages = {17}, year = {2018}, abstract = {Climate change challenges forest vitality both directly by increasing drought and heat periods and indirectly, e.g., by creating favorable conditions for mass outbreaks of phyllophagous insects. The large forests dominated by Scots pine (Pinus sylvestris L.) that cover the lowland regions in northeast Germany have already been affected regularly by cyclic mass propagations of defoliating insect species in the past with climate projections implying an even more advantageous environment for devastating outbreaks in the future. To improve predictive and responsive capacities we have investigated a wide range of ecological parameters to identify those most strongly related to past outbreak waves of three central species. In total, we analyzed 3,748 variables covering stand and neighborhood properties, site quality, and climatic conditions for an area of roughly 750,000 ha of pine forests in the period 2002-2016. To reflect sensitivity against varying climate, we computed "floating windows" in relation to critical phenological phases of the respective insects. The parameters with the highest explanatory power resulted from the variable importance measures of the Random Forest (RF) methodology and have been evaluated by a 10-fold cross-validation process. Our findings closely reflect the known specific gradation patterns and show that relative variable importance varies with species. While Lymantria monacha L. feeding was mainly dependent on the surroundings of the respective stand, Diprion pini L. proved to be almost exclusively susceptible to climatic effects in its population dynamics. Dendrolimus pini L. exhibited a mixed pattern of variable importance involving both climatic and forest structure parameters. In many cases the obtained statistical results support well-known ecological cause-effect relations and long-term population change dynamics. The RF delivered very high levels of sensitivity and specificity in the developed classifications and proved to be an excellent tool to handle the large amounts of data utilized for this study. While the presented classification approach may already support a better prognosis of the amplitude during the outbreak culmination, the obtained (most important) variables are proposed as preferable covariates for modeling population dynamics of the investigated insect species.}, language = {en} } @article{MissallAblizHaliketal.2018, author = {Missall, Siegmund and Abliz, Abdulla and Halik, {\"U}m{\"u}t and Thevs, Niels and Welp, Martin}, title = {Trading Natural Riparian Forests for Urban Shelterbelt Plantations—A Sustainability Assessment of the K{\"o}kyar Protection Forest in NW China}, series = {Water}, journal = {Water}, number = {10(3)}, issn = {2073-4441}, doi = {10.3390/w10030343}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-5022}, pages = {18}, year = {2018}, abstract = {Cities at the fringe of the Taklimakan desert in NW China are prone to dust and sand storms with serious consequences for human well-being. The K{\"o}kyar Protection Forest was established in the 1980s as an ecological engineering project with the intent of protecting the city of Aksu, NW China, from these impacts. It is designed as a combination of poplar shelterbelts and orchards, irrigated by river water from the Aksu River, the main tributary of the Tarim River. Prevalent literature describes it as an afforestation project for combatting desertification with manifold positive effects for the economic, social, and environmental dimension of sustainable development. This paper sets out to challenge these claims by a sustainability assessment in which the plantation is examined from a broader perspective, embedding it to the wider context of social and environmental problems in South Xinjiang. Methods comprise evapotranspiration calculations, interviews, a socioeconomic household survey, stakeholder dialogues, and literature research. Results affirm its economic sustainability, but see a mixed record for the social sphere. From the nature conservation point of view, it has to be classified as unsustainable because its high irrigation water consumption results in the downstream desiccation and desertification of natural riparian forests along the Tarim River, causing a forest loss in the downstream area twice the size of the forest gain in the upstream area. There is a trade-off between artificial shelterbelt plantations for urban ecosystem services on the one hand side, and natural riparian forests and their biodiversity on the other hand side. The paper recommends restricting agricultural extension, and using locally adapted less water consuming agroforestry schemes to protect urban dwellers from dust stress.}, language = {en} } @inproceedings{SchmidtSchmidtSchweigeretal.2018, author = {Schmidt, Henriette and Schmidt, Markus and Schweiger, Julienne M.-I. and Lenz, Claudia and Hartmann, Holger and Pflugmacher, Candy and G{\"o}tz, Bernhard and Gebauer, Gerhard and Schill, Harald}, title = {Climate sensitivity of rare native tree species in NE-Germany - A dendroecological and ecophysiological approach}, doi = {10.57741/opus4-761}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-7610}, pages = {1}, year = {2018}, language = {en} }