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Peatlands contribute to a wide range of ecosystem services. They play an important role as carbon sinks in their natural state, but when they are drained, they cause carbon emissions. Rewetting drained peatlands is required to reduce carbon emissions and create new carbon sinks. However, drained peatlands are commonly used as grassland or croplands; therefore, alternative agriculture schemes are required following rewetting. Paludiculture, i.e., agriculture on wet and rewetted peatlands, is an option in these areas after rewetting to produce biomass sustainably. Monitoring of peatland management is challenging, yet needed to ensure a successful rewetting and plantation of, e.g., Phragmites australis and Typha spp., two plants which are commonly used in paludiculture. Remote sensing is an excellent tool for monitoring the vegetation composition of vast rewetted peatland regions. However, because many peatland species have similar spectral characteristics, such monitoring is ideally based on high-spatial, high-temporal hyperspectral images. Data that complies with all these requirements does not exist on a regular basis. Therefore, we assessed the potential for mapping peatland vegetation communities in the Peene and Trebel river basins of the federal state of Mecklenburg-Western Pomerania, Germany, using multi-date hyperspectral (PRISMA) data. We used regression-based unmixing to map fractions of different peatland vegetation classes. Results were analyzed with regard to the contribution of multi-date observations and, in comparison, to multispectral datasets (Landsat-8/Sentinel-2). Our results showed that different classes are best mapped at different observation dates. The multi-date hyperspectral datasets produced less Mean Absolute Error (MAE = 16.4%) than the single-date hyperspectral images (ΔMAE + 1%), with high accuracies for all classes of interest. Compared to the results obtained with multispectral data from similar acquisition dates and annual spectral-temporal metrics (STM), the results from hyperspectral data were always clearly superior (ΔMAE + 4%). Besides the superior performance during comparisons, our results also indicate that information that can be derived from the hyperspectral data with the regression-based unmixing goes clearly beyond that of discrete classification. With more hyperspectral sensors coming up and an expected higher availability of multi-data hyperspectral imagery, these data can be expected to play a bigger role in the future monitoring of peatlands.
Das vorliegende Essay gibt einen Überblick zum Standortauswahlprozess für die Endlagerung des hochradioaktiven Abfalls in der Bundesrepublik Deutschland. Dieses Verfahren stellt einen Paradigmenwechsel gegenüber dem früheren Versuch der Ausweisung eines Standortes dar, indem zunächst einzig geologische Kriterien hinsichtlich der Sicherheit der Einlagerung und nicht politisch-wirtschaftliche Einzelinteressen von Regionen entscheidend sein sollen. Der aktuelle Stand der Forschung bildet weitergehende Wissensbedarfe gut ab. Derzeit besonders diskutierte Aspekte im Rahmen der Einengung der großen Teilgebiete auf Standortregionen zur übertägigen Erkundung werden angesprochen.
Monitoring and assessing groundwater quality according to European directives and national regulations is usually based on interpolation techniques, e.g. Kriging. However, contour maps of hydrochemical parameters often suggest a spurious local accuracy and can therefore lead to inappropriate action measures. Here, the early concept of extension variance combined with the Voronoi tessellation regionalization is proposed. The mosaic-like representation of pollutant concentrations in Voronoi polygons avoids misinterpretations caused by interpolation. The additional calculation of the extension variance, which is based on fundamental geostatistical assumptions, allows for estimating the probability that a given threshold is exceeded. This concept is further extended to hydraulically delimitable groundwater bodies, thus ensuring that hydraulic boundaries are considered. A method is here described for the assessment of groundwater quality with respect to nitrate concentration in the principal aquifer of the state Mecklenburg-Western Pomerania in Germany.
Der inhabergeführte Einzelhandel steht vor besonderen Herausforderungen bei der Einführung und Etablierung digitaler Kundenkommunikationsmaßnahmen (KKM). Im vorliegenden Beitrag wird untersucht, welche Maßnahmen im Zuge der Coronapandemie eingeführt worden sind und welche dieser Maßnahmen besonders zukunftsfähig sein können. Darüber hinaus wird die Bedeutung von regionalen Netzwerken beim Wissenstransfer über digitale Maßnahmen betrachtet. Für die Untersuchung wurde in den drei Bundesländern Nordrhein-Westfalen, Sachsen und Sachsen-Anhalt im März 2022 eine Online-Befragung von Inhabern durchgeführt und durch fünf Experteninterviews im April und Mai 2022 ergänzt. Für die Vergleichbarkeit der gewonnenen Ergebnisse wird eine großflächige Handelsstudie der IHK Köln und dem ibi Research Institut Regensburg aus dem Jahr 2020 herangezogen. Dabei stellte sich heraus, dass insbesondere die digitale Sichtbarkeit für den Erhalt der inhabergeführten Einzelhandelsgeschäfte in Zukunft von zentraler Bedeutung sein wird. Ferner präsentieren sich die sozialen Medien mit ihrer perspektivisch ausgestatteten Verkaufsfunktion als geeignetes Instrument. Außerdem konnten durch eine differenzierte Betrachtung von Branchen und Zielgruppen sowie unterschiedlichen Ansätzen für den Einstieg in die digitale Kundenkommunikation zukunftsfähige und individuelle Maßnahmen identifiziert werden.
Nebenströme der Agrar- und Ernährungswirtschaft – vom Abfallprodukt zur wertvollen Ressource!?
(2023)
Die Nutzung von organischen Abfällen und Nebenströmen ist ein wichtiger Baustein für die Transformation zu einem nachhaltige(re)n Agrar- und Ernährungssystem. Die damit einhergehenden Kreislaufsysteme werden in der Literatur unter dem Begriff der Circular Bioeconomy diskutiert. Der Beitrag greift diese Diskussionen auf und liefert empirische Befunde aus der Raps- und Zuckerrübenproduktion, wo große Mengen an Nebenströmen speziell auf der Verarbeitungsstufe anfallen (z. B. Presskuchen, Extraktionsschrot, Rübenschnitzel, Melasse). Für diese organischen Stoffe haben sich unterschiedliche Verwertungspfade etabliert, sodass sie mittlerweile ein wichtiges Element der betrieblichen Wertschöpfung darstellen. Die Verwertung geschieht in beiden Bereichen durch intersektorale Vernetzungen, die sich je nach Wertschöpfungspotenzial und Lager‑/Transportfähigkeit der Biomasse über verschiedene Raumebenen erstrecken (lokal/regional, national, international). Ebenso spielen unternehmerische Merkmale wie auch der institutionelle Kontext eine Rolle bei der Nebenstromverwertung.
The reduction of individual carbon consumption could make an important contribution to the worldwide effort to limit global warming. Based on Bandura’s theory of moral disengagement, we hypothesized that the propensity to morally disengage concerning high-carbon behaviors (e.g., eating meat or traveling by plane) is one important factor that prevents individuals from reducing their carbon footprint. To measure the propensity to morally disengage in high-carbon-related behavior contexts, a questionnaire (MD-HCB) was developed and psychometrically validated in an online study with a German sample (N = 220). Confirmatory factor analyses revealed that the final nine-item scale had a one-dimensional structure, as intended. The internal consistency of the scale was excellent (Cronbach’s α = 0.94) and the scale interpretation had predictive validity for both past low-carbon consumption behavior and the intention to engage in such behavior in the future. Correlational analyses with relevant existing instruments confirmed the construct validity of the interpretations that can be drawn from the MD-HCB, as its resulting score is related to, yet separable from, the general tendency to morally disengage and is meaningfully connected to related constructs. A pre-study with a student sample (N = 89) not only helped to identify limitations in the study design but also showed a weak predictive ability of moral competence concerning high-carbon consumption behavior and intention to change. Based on our findings, future media campaigns designed to increase people’s intention to reduce high-carbon behavior could focus on the modification of common cognitive disengagement strategies.
The multi-level perspective has been criticized for being functionalistic and paying little attention to actor-based perspectives. Nevertheless, for the identification and assessment of potential change agents in a sustainability transition, a clear conceptual and methodological approach is necessary. This paper, thus, develops a multi-dimensional typology of niche, regime, and hybrid actors, which is conceptually grounded in transition studies and empirically illustrated by a cluster analysis based on a survey of pig and poultry farmers in Germany, France, and the Netherlands. Animal husbandry is chosen as a case study because a significant share of the environmental impact within the agri-food system is attributed to this sector and there is evidence for resistance to change by mainstream actors. Conceptually, the paper provides a framework of constitutive elements for different kinds of actors and contributes to an extension of the niche–regime dichotomy by adding the group of hybrid actors. The empirical results show that cluster analysis is a suitable approach to identify conceptually meaningful differences among interviewed farmers. Among pig and poultry farmers, the regime actors are by far the largest group. The smaller group of hybrid actors, however, has large potential to act as boundary spanners. A particularly interesting finding is that several larger farms are among the group of niche actors which hints at the possibility that larger farms are not necessarily resistant to change.
The occurrence and distribution of organochlorine pesticides (OCPs) in aquatic systems is a matter of global concern and poses significant toxicological threats to both organisms and human health. Despite the extensive use of OCPs for pest and disease control in southern Africa, relatively few studies have examined the occurrence and toxicological risks of OCP residues in the region. This study investigates the composition, distribution, and potential sources of OCP contamination in sediments from Richards Bay, a rapidly developing industrial port on the northeast coast of South Africa. Surface sediments collected from Richards Bay Harbour and surrounding areas indicate that OCP contamination in the region is widespread. Total concentrations (∑OCP) in surface samples ranged from 135 to 1020 ng g−1, with hexachlorocyclohexanes (∑HCH; 35–230 ng g−1) and dichlorodiphenyltrichloroethanes (∑DDT; 12–350 ng g−1) the dominant contaminant groups detected. Metabolite isomeric compositions indicate that the presence of aldrin and endosulfan likely result from historical agricultural usage, while recent input of γ-HCH, heptachlor, and endrin may be linked to the illegal use of old pesticide stockpiles. Total DDT concentrations were dominated by p,p′-DDT (80 ± 64 ng g−1), which was attributed to its ongoing use in malaria vector control in the region. A 210Pb-dated sediment core revealed that OCP input to the local environment increased dramatically from relatively low concentrations in the mid-1940s (∑OCP, 355 ng g−1) to peak levels (∑OCP, 781 ng g−1) in the 1980s/1990s. An overall decrease in ∑OCP concentration from the mid-2000s is likely related to restrictions on use following the Stockholm Convention in 2004. Despite current restrictions on use, OCP concentrations exceeded sediment quality guidelines in the vast majority of cases, raising concerns for protected estuarine and mangrove habitats in the area, as well as for local fishing and farming communities.
Thermally treated kaolinite is used to develop a range of alumino‐silicate‐based precursor materials but its behavior during plasma spraying has not been well‐researched. In this study, two types of kaolinite samples were investigated in the form of low defect (KGa‐1b) and high defect (KGa‐2) varieties. The extreme temperatures of the plasma stream (up to 20 000 K) induced flash melting to produce a highly porous alumino‐silicate glass without any crystallization of new Al−Si oxide minerals. The glass is comprised largely of intact or deformed spheres (average diameters 1.14–1.44 μm), which indicates rapid quenching and solidification before impact. The subspherical structures contain up to 40 % closed pore space caused by the rapid escape of water during melting. The low‐density, porous alumino‐silicate glass coatings with predicted specific surface areas (>0.95 m2/g) and hardnesses >1.8 GPa represent a potentially reactive but physically stable substrate ideal for further chemical functionalization.
Late Pleistocene glacitectonism at the southern Scandinavian Ice Sheet margin caused folding and thrusting of Upper Cretaceous chalk layers and Pleistocene glacial deposits in parts of the southwestern Baltic Sea area in Europe. Beside Møns Klint (SE Denmark), the Jasmund Glacitectonic Complex (JGC) on Rügen Island (NE Germany) is a similar striking example of glacitectonic deformation creating large composite ridges. In spite of a long research history and new results from modern datasets, the structural development of the JGC is still poorly understood, especially the detailed evolution of the southern JGC and its relationship to the northern JGC remain enigmatic. In this contribution, we demonstrate how the understanding of the JGC benefits from the application of established structural geological methods comprehending the formation of fold-and-thrust belts. The methods include cross-section balancing of the eastern coast (southern JGC) and quantification of the amount of folding and faulting. The proposed geometric model shows the current fold-and-thrust stack of glacially deformed sedimentary strata ca. 5720 m in length evolved by shortening from the original length (11,230 m) by 5510 m (49.1%). We present a spatial and temporal development of fault-related folding with a transition from detachment folds through fault-propagation folds to fault-bend folds. Together with morphological information from a digital elevation model, the thrust faults mapped in the cliff section are mainly inclined towards the S to SW and imply that a local glacier push occurred from the south. These results highlight the complexity and individual architecture of the JGC when compared to other Pleistocene and modern glacitectonic complexes. Resolving its structural development provides new insight into the deformation history and shortening of this spectacular glacitectonic complex lying in the southwestern Baltic Sea region.