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Soil degradation due to erosion is a significant worldwide problem at different spatial (from pedon to watershed) and temporal scales. All stages and factors in the erosion process must be detected and evaluated to reduce this environmental issue and protect existing fertile soils and natural ecosystems. Laboratory studies using rainfall simulators allow single factors and interactive effects to be investigated under controlled conditions during extreme rainfall events. In this study, three main factors (rainfall intensity, inclination, and rainfall duration) were assessed to obtain empirical data for modeling water erosion during single rainfall events. Each factor was divided into three levels (− 1, 0, + 1), which were applied in different combinations using a rainfall simulator on beds (6 × 1 m) filled with soil from a study plot located in the arid Sistan region, Iran. The rainfall duration levels tested were 3, 5, and 7 min, the rainfall intensity levels were 30, 60, and 90 mm/h, and the inclination levels were 5, 15, and 25%. The results showed that the highest rainfall intensity tested (90 mm/h) for the longest duration (7 min) caused the highest runoff (62 mm3/s) and soil loss (1580 g/m2/h). Based on the empirical results, a quadratic function was the best mathematical model (R2 = 0.90) for predicting runoff (Q) and soil loss. Single-factor analysis revealed that rainfall intensity was more influential for runoff production than changes in time and inclination, while rainfall duration was the most influential single factor for soil loss. Modeling and three-dimensional depictions of the data revealed that sediment production was high and runoff production lower at the beginning of the experiment, but this trend was reversed over time as the soil became saturated. These results indicate that avoiding the initial stage of erosion is critical, so all soil protection measures should be taken to reduce the impact at this stage. The final stages of erosion appeared too complicated to be modeled, because different factors showed differing effects on erosion.
Laboratory landslide experiments enable the observation of specific properties of these natural hazards. However, these observations are limited by traditional techniques: frequently used high-speed video analysis and wired sensors (e.g. displacement). These techniques lead to the drawback that either only the surface and 2D profiles can be observed or wires confine the motion behaviour. In contrast, an unconfined observation of the total spatiotemporal dynamics of landslides is needed for an adequate understanding of these natural hazards.
The present study introduces an autonomous and wireless probe to characterize motion features of single clasts within laboratory-scale landslides. The Smartstone probe is based on an inertial measurement unit (IMU) and records acceleration and rotation at a sampling rate of 100 Hz. The recording ranges are ±16 g (accelerometer) and ±2000∘ s−1 (gyroscope). The plastic tube housing is 55 mm long with a diameter of 10 mm. The probe is controlled, and data are read out via active radio frequency identification (active RFID) technology. Due to this technique, the probe works under low-power conditions, enabling the use of small button cell batteries and minimizing its size.
Using the Smartstone probe, the motion of single clasts (gravel size, median particle diameter d50 of 42 mm) within approx. 520 kg of a uniformly graded pebble material was observed in a laboratory experiment. Single pebbles were equipped with probes and placed embedded and superficially in or on the material. In a first analysis step, the data of one pebble are interpreted qualitatively, allowing for the determination of different transport modes, such as translation, rotation and saltation. In a second step, the motion is quantified by means of derived movement characteristics: the analysed pebble moves mainly in the vertical direction during the first motion phase with a maximal vertical velocity of approx. 1.7 m s−1. A strong acceleration peak of approx. 36 m s−2 is interpreted as a pronounced hit and leads to a complex rotational-motion pattern. In a third step, displacement is derived and amounts to approx. 1.0 m in the vertical direction. The deviation compared to laser distance measurements was approx. −10 %. Furthermore, a full 3D spatiotemporal trajectory of the pebble is reconstructed and visualized supporting the interpretations. Finally, it is demonstrated that multiple pebbles can be analysed simultaneously within one experiment. Compared to other observation methods Smartstone probes allow for the quantification of internal movement characteristics and, consequently, a motion sampling in landslide experiments.
Phylogeographic analyses point to long-term survival on the spot in micro-endemic Lycian salamanders
(2020)
Lycian salamanders (genus Lyciasalamandra) constitute an exceptional case of microendemism of an amphibian species on the Asian Minor mainland. These viviparous salamanders are confined to karstic limestone formations along the southern Anatolian coast and some islands. We here study the genetic differentiation within and among 118 populations of all seven Lyciasalamandra species across the entire genus’ distribution. Based on circa 900 base pairs of fragments of the mitochondrial 16SrDNA and ATPase genes, we analysed the spatial haplotype distribution as well as the genetic structure and demographic history of populations. We used 253 geo-referenced populations and CHELSA climate data to infer species distribution models which we projected on climatic conditions of the Last Glacial Maximum (LGM). Within all but one species, distinct phyloclades were identified, which only in parts matched current taxonomy. Most haplotypes (78%) were private to single populations. Sometimes population genetic parameters showed contradicting results, although in several cases they indicated recent population expansion of phyloclades. Climatic suitability of localities currently inhabited by salamanders was significantly lower during the LGM compared to recent climate. All data indicated a strong degree of isolation among Lyciasalamandra populations, even within phyloclades. Given the sometimes high degree of haplotype differentiation between adjacent populations, they must have survived periods of deteriorated climates during the Quaternary on the spot. However, the alternative explanation of male biased dispersal combined with a pronounced female philopatry can only be excluded if independent nuclear data confirm this result.
Climate change is expected to cause mountain species to shift their ranges to higher elevations. Due to the decreasing amounts of habitats with increasing elevation, such shifts are likely to increase their extinction risk. Heterogeneous mountain topography, however, may reduce this risk by providing microclimatic conditions that can buffer macroclimatic warming or provide nearby refugia. As aspect strongly influences the local microclimate, we here assess whether shifts from warm south-exposed aspects to cool north-exposed aspects in response to climate change can compensate for an upward shift into cooler elevations.
Es wird ein Workshopkonzept dargelegt, um das im Rahmen des PODMAN-Projektes entwickelte DIAMANTModell zur Implementierung einer institutionellen FDM-Servicelandschaft kennenzulernen. Anhand von Beispielen erfahren die Teilnehmenden, wie die entwickelten Instrumente auf die eigene Forschungseinrichtung angewendet werden. Primär wird das Konzept für den Initial-Workshop vorgestellt, der alle FDM-Akteur*innen
einer Forschungseinrichtung zusammenbringt, um das DIAMANT-Modell zunächst auf die gesamte Forschungseinrichtung zu applizieren. Daraus wurde ein weiteres Workshopkonzept abgeleitet, das insbesondere für die fach- oder abteilungsspezifische Bedarfserhebung vorgesehen ist.
Der Tagungsbericht fasst die Vorträge, Workshops und Ergebnisse der Abschlusstagung des BMBF-Projektes PODMAN: „Forschung + Datenmanagement = Forschungsdatenmanagement – Wann geht die Gleichung auf?“ vom 27. und 28. März 2019 an der Universität Trier zusammen. Ihm sind die Vortragsfolien, die Präsentationen der Workshops sowie die zugehörige Fotodokumentation der Arbeitsgruppen im Anhang beigefügt.
Although gravitropism forces trees to grow vertically, stems have shown to prefer specific orientations. Apart from wind deforming the tree shape, lateral light can result in prevailing inclination directions. In recent years a species dependent interaction between gravitropism and phototropism, resulting in trunks leaning down-slope, has been confirmed, but a terrestrial investigation of such factors is limited to small scale surveys. ALS offers the opportunity to investigate trees remotely. This study shall clarify whether ALS detected tree trunks can be used to identify prevailing trunk inclinations. In particular, the effect of topography, wind, soil properties and scan direction are investigated empirically using linear regression models. 299.000 significantly inclined stems were investigated. Species-specific prevailing trunk orientations could be observed. About 58% of the inclination and 19% of the orientation could be explained by the linear models, while the tree species, tree height, aspect and slope could be identified as significant factors. The models indicate that deciduous trees tend to lean down-slope, while conifers tend to lean leeward. This study has shown that ALS is suitable to investigate the trunk orientation on larger scales. It provides empirical evidence for the effect of phototropism and wind on the trunk orientation.
The parameterization of the boundary layer is a challenge for regional climate models of the Arctic. In particular, the stable boundary layer (SBL) over Greenland, being the main driver for substantial katabatic winds over the slopes, is simulated differently by different regional climate models or using different parameterizations of the same model. However, verification data sets with high-resolution profiles of the katabatic wind are rare. In the present paper, detailed aircraft measurements of profiles in the katabatic wind and automatic weather station data during the experiment KABEG (Katabatic wind and boundary-layer front experiment around Greenland) in April and May 1997 are used for the verification of the regional climate model COSMO-CLM (CCLM) nested in ERA-Interim reanalyses. CCLM is used in a forecast mode for the whole Arctic with 15 km resolution and is run in the standard configuration of SBL parameterization and with modified SBL parameterization. In the modified version, turbulent kinetic energy (TKE) production and the transfer coefficients for turbulent fluxes in the SBL are reduced, leading to higher stability of the SBL. This leads to a more realistic representation of the daily temperature cycle and of the SBL structure in terms of temperature and wind profiles for the lowest 200 m.
Das DIAMANT-Modell wurde im Rahmen des BMBF-geförderten Projekts „Prozessorientierte Entwicklung von Managementinstrumenten für Forschungsdaten im Lebenszyklus“ (PODMAN) entwickelt. Das grundsätzliche Ziel des Modells besteht darin, Hochschulen und außeruniversitäre Forschungseinrichtungen zu befähigen, eine integrierte Informationsarchitektur für die optimierte Bereitstellung und Weiterentwicklung von Forschungsdatenmanagement (FDM)-Technologien und -services aufzubauen und zu pflegen, sodass die Forschenden ihre Forschungsdatensätze zu „hochkarätigen Diamanten“ schleifen können. Das DIAMANTModell besteht zum einen aus dem FDM-Referenzprozess, der – angelehnt an die ARIS-Prozessmodellierung – den gesamten FDM-Prozess und die zugehörigen Akteur*innen darstellt und ihren Grad der Beteiligung / Verantwortung an einem FDM-Service benennt. Der FDM-Referenzprozess sieht die Etablierung einer zentralen FDM-Steuerungseinheit vor, die den Informationsfluss zwischen allen am FDM beteiligten Organisationseinheiten steuert. Ein weiterer Bestandteil des DIAMANT-Modells ist die FDM-Kompetenzmatrix, die sich aus dem FDM-Referenzprozess ableitet. Sie dient der IST- / SOLL-Analyse, um den Referenzprozess auf die eigene Institution übertragen zu können. Abgeleitet wurde auch ein Beschreibungsmodell für FDMServices, um einen FDM-Service- /-Anforderungskatalog zu entwickeln und institutsspezifisch fortzuschreiben. Letzter Teil des DIAMANT-Modells sind Empfehlungen, welche Aspekte hinsichtlich der Personalführung und des Organisationsmanagements bei der Implementierung der FDM-Servicelandschaft berücksichtigt werden sollten.
Hochschulen und außeruniversitäre Forschungseinrichtungen werden heute zunehmend in die Pflicht genommen, für ihre Forschenden Strukturen und Services für ein nachhaltiges Forschungsdatenmanagement (FDM) bereit-zustellen. Da es vor allem für disziplin- oder datenspezifische Bedarfe nicht für jede Forschungseinrichtung möglich ist, die dafür notwendigen Dienste selbst vorzuhalten, müssen sie externe Dienstleistungen in ihre FDM-Servicestrukturen integrieren. Das erfolgreiche Management der Schnittstelle zwischen den kooperierenden Insti-tutionen bedeutet einen erheblichen Organisationsaufwand, für den der vorliegende Praxisleitfaden eine Hilfe-stellung bietet. Er soll die Einrichtungen in die Lage versetzen, fremdbezogene FDM-Dienstleistungen erfolgreich in ihr eigenes FDM-Serviceangebot bzw. ihre übergeordnete FDM-Strategie zu integrieren. Der Leitfaden dient insbesondere als Anleitung für die erfolgreiche Steuerung der Zusammenarbeit und Kommunikation der invol-vierten internen und externen Mitarbeiter*innen. Über eine Reihe von Steuerungsmechanismen, die in diesem Leitfaden ausführlich erläutert werden, lässt sich der Prozess des Schnittstellenmanagements bestmöglich hand-haben. Der Praxisleitfaden versteht sich als Arbeitsgrundlage für alle Akteur*innen einer Forschungseinrichtung, die an der Erstellung eines institutionellen FDM-Konzeptes beteiligt sind.