Stakeholders’ Views on Multimodal Urban Mobility Futures: A Matter of Policy Interventions or Just the Logical Result of Digitalization?

It is widely acknowledged that strategies to decarbonize energy systems cannot omit the mobility sector. For several decades, particularly in urban areas, a shift from car-based mobility to more environmental-friendly modes has been high on political agendas. Progress has been made in many urban areas, but so far only in small, rather incremental steps. The dominance of the car has remained largely stable in urban transport. For some time now, many experts have argued that processes of digitalization will co-evolve with societal trends and lead to multimodal urban mobility regimes in which private car usage will lose its dominance. In this paper, we examine if stakeholders active in the field believe that, despite digitalization, policy interventions are essential to achieve such a transition. The analysis draws on concepts from transition research and is based on 10 semi-structured interviews with providers of innovative mobility services that may contribute to more multimodal urban mobility systems. Geographical focus is on the City of Stuttgart (Germany). Results indicate broad agreement amongst the interviewees that digitalization alone is not sufficient for achieving a full-scale transition towards multimodal urban mobility. Policy measures that restrict car-based mobility would also be needed. However, many of the interviewed actors doubt that the essential policy mixes will find the necessary political and societal acceptance. Finally, the paper indicates ways to overcome this dilemma

Operational tsunami modelling with TsunAWI – recent developments and applications

In this article, the tsunami model TsunAWI (Alfred Wegener Institute) and its application for hindcasts, inundation studies, and the operation of the tsunami scenario repository for the Indonesian tsunami early warning system are presented. TsunAWI was developed in the framework of the German-Indonesian Tsunami Early Warning System (GITEWS) and simulates all stages of a tsunami from the origin and the propagation in the ocean to the arrival at the coast and the inundation on land. It solves the non-linear shallow water equations on an unstructured finite element grid that allows to change the resolution seamlessly between a coarse grid in the deep ocean and a fine representation of coastal structures. During the GITEWS project and the following maintenance phase, TsunAWI and a framework of pre- and postprocessing routines was developed step by step to provide fast computation of enhanced model physics and to deliver high quality results

Soft-bottom tidepools within mixed reefs of native mussels and introduced oysters – refuge for associated species and parasites?

The introduction of Pacific oysters to the sedimentary south-eastern North Sea coast and their establishment on intertidal native blue mussel beds has caused the development of mixed reefs of mussels and oysters with extensive tidepools. Tidepools have been intensively studied at rocky shores where they show community structures, which usually differ from that of the surrounding emerging substrates. Tidepools at sedimentary coasts, however, have received less attention. We compared the community structure and species interactions inside and outside tidepools in oyster reefs by determining densities of snails, barnacles and amphipods. Snail densities were similar in and outside tidepools. Barnacle coverage on bivalve shells, however, was lower inside tidepools, which may be caused by higher predation pressure and increased snail grazing under permanently submerged conditions, as was revealed by field and laboratory experiments. Additionally, we studied the occurrence of copepod and trematode parasites in blue mussels inside and outside tidepools. Prevalence and intensity of parasitic copepods was higher in mussels inside tidepools. Trematode parasites, by contrast, showed a lower intensity in mussels inside tidepools. This can be explained by high amphipod densities found inside tidepools because trematode larvae represent a food source of amphipods. Our study suggests that the community structure of oyster reefs within tidepools is not a submerged equivalent to that of intertidal reefs. As their counterparts at rocky shores, they show their own species distribution patterns with particular species interactions and only provide refuge for specific species such as parasitic copepods

Soft-bottom tidepools within mixed reefs of native mussels and introduced oysters - refuge for associated species and parasites?

The introduction of Pacific oysters to the sedimentary south-eastern North Sea coast and their establishment on intertidal native blue mussel beds has caused the development of mixed reefs of mussels and oysters with extensive tidepools. Tidepools have been intensively studied at rocky shores where they show community structures, which usually differ from that of the surrounding emerging substrates. Tidepools at sedimentary coasts, however, have received less attention. We compared the community structure and species interactions inside and outside tidepools in oyster reefs by determining densities of snails, barnacles and amphipods. Snail densities were similar in and outside tidepools. Barnacle coverage on bivalve shells, however, was lower inside tidepools, which may be caused by higher predation pressure and increased snail grazing under permanently submerged conditions, as was revealed by field and laboratory experiments. Additionally, we studied the occurrence of copepod and trematode parasites in blue mussels inside and outside tidepools. Prevalence and intensity of parasitic copepods was higher in mussels inside tidepools. Trematode parasites, by contrast, showed a lower intensity in mussels inside tidepools. This can be explained by high amphipod densities found inside tidepools because trematode larvae represent a food source of amphipods. Our study suggests that the community structure of oyster reefs within tidepools is not a submerged equivalent to that of intertidal reefs. As their counterparts at rocky shores, they show their own species distribution patterns with particular species interactions and only provide refuge for specific species such as parasitic copepods

Entwicklung von nachhaltigen Verfahren zur Abwehr von Feldmäusen (Microtus arvalis)

Feldmäuse (Microtus arvalis) können schwere Schäden in der europäischen Landwirtschaft verursachen und werden bei Bedarf mit Rodentiziden bekämpft. Nicht-chemische, großflächig anwendbare Alternativen stehen nicht zur Verfügung, was besonders im ökologischen Anbau ein Problem ist. Potenziell geeignete nachhaltige Methoden wurden im Labor entwickelt und in Feldversuchen an Feldrändern angewendet: 1) Pflugfurche mit Repellentien auf abbaubarem Trägermaterial (Dispenser); 2) Pflugfurche mit „Selbstbedienungsfallen“ für Prädatoren, die mit einem attraktiven Feldmaus-Köder bestückt sind. Eine am Markt verfügbare Selbstbedienungsfalle ist die Standby-Box (Andermatt Biocontrol AG). Dieser Fallen-Typ wurde mit der im Projekt entwickelten Fangwanne verglichen, die an die Form der Pflugfurche angepasst ist. In Feldversuchen stellte sich heraus, dass die Fangwanne zwei entscheidende Vorteile hat. Durch die obere Öffnung 1) können Langschwanzmäuse entkommen (weniger Beifang); 2) haben Vögel Zugang zu Feldmäusen in der Falle. Dementsprechend konnten mehr Prädatoren und Feldmaus-Entnahmen bei den Fangwannen beobachtet werden. In Gehegeversuchen unterschied sich die Fängigkeit beider Fallen nicht. Die Fängigkeit der Feldmäuse kann durch einen attraktiven Köder erhöht werden. Im Labor wurden 22 Naturstoffe gescreent. Mit den drei erfolgversprechendsten Stoffen Bisabolol, Eugenol und Maltol als Attraktantien und einer Luzerne-Getreidemischung als Köder-Basis wurden drei neue Köder in Pelletform formuliert. In Gehegeversuchen konnte der Maltol-Köder die Fängigkeit um 60% im Vergleich zum Kontroll-Köder (Pellets ohne Attraktanz) erhöhen. Die Köderaufnahme war jedoch bei den Kontroll-Pellets bei allen drei Varianten höher. Als geeignetes Feldmaus-Repellent wurden 17 Stoffe im Labor gescreent und die vier erfolgversprechendsten Stoffe Benzaldehyd, Fichtennadel-, Karottensamen- (KS) und Schwarzer Pfefferöl (SP) im Gehege getestet. Mit Schwarzer Pfefferöl konnten die geringste Migrationsrate und mit der Kombination aus SP + KS die geringste Futteraufnahme erzielt werden. Als Dispenser setzte sich das Zellstoffband vor den Zellstoffkugeln und dem Tongranulat durch. Die Repellent-Variante mit SP + KS auf Zelluloseband sowie die Fangwannen mit dem Maltol-Köder wurden in Feldversuchen in Pflugfurchen am Feldrand ausgebracht und mit zwei experimentellen Kontrollen verglichen 1) Zinkphosphid-Applikation in unterirdische, künstliche Tunnel mit der Mäuseköderlegemaschine WUMAKI C9 und 2) kein Management. In dem über drei aufeinanderfolgenden Jahren durchgeführten Feldversuchsprogramm kam es auf keinem der jeweils fünf Versuchsstandorte zu einer Feldmaus-Massenvermehrung. Durch das geringe Feldmausauftreten im Zeitraum 2015/16-2017/18 sind Aussagen zur Wirksamkeit der Management-Methoden unter Feldbedingungen nicht möglich. Wenn die Barrierewirkung während einer Massenvermehrung verifiziert werden kann, wäre dies ein Schritt zu einem ökologisch verträglichen und nachhaltigen Feldmaus-Management

Disentangling coastal groundwater level dynamics on a global data set

This study aims to identify common hydrogeological patterns and to gain a deeper understanding of the underlying similarities and their link to physiographic, climatic, and anthropogenic controls of coastal groundwater. The most striking aspects of GWL dynamics and their controls were identified through a combination of statistical metrics, calculated from about 8,000 groundwater hydrographs, and pattern recognition, classification, and explanation using machine learning techniques and SHapley Additive exPlanations (SHAP). Overall, four different GWL dynamics patterns emerge, independent of the different seasons, time series lengths, and periods. We show in this study that similar GWL dynamics can be observed around the world with different combinations of site characteristics, but also that the main factors differentiating these patterns can be identified. Three of the identified patterns exhibit high short-term and interannual variability and are most common in regions with low terrain elevation and shallow groundwater depth. Climate and soil characteristics are most important in differentiating these patterns. This study provides new insights into the hydrogeological behavior of groundwater in coastal regions and guides systematic and holistic groundwater monitoring and modelling, motivating to consider various aspects of GWL dynamics when, for example, estimating climate-driven GWL changes &ndash; especially when information on potential controls is limited.</p

Assessing criticality in pre-seizure single-neuron activity of human epileptic cortex

Epileptic seizures are characterized by abnormal and excessive neural activity, where cortical network dynamics seem to become unstable. However, most of the time, during seizure-free periods, cortex of epilepsy patients shows perfectly stable dynamics. This raises the question of how recurring instability can arise in the light of this stable default state. In this work, we examine two potential scenarios of seizure generation: (i) epileptic cortical areas might generally operate closer to instability, which would make epilepsy patients generally more susceptible to seizures, or (ii) epileptic cortical areas might drift systematically towards instability before seizure onset. We analyzed single-unit spike recordings from both the epileptogenic (focal) and the nonfocal cortical hemispheres of 20 epilepsy patients. We quantified the distance to instability in the framework of criticality, using a novel estimator, which enables an unbiased inference from a small set of recorded neurons. Surprisingly, we found no evidence for either scenario: Neither did focal areas generally operate closer to instability, nor were seizures preceded by a drift towards instability. In fact, our results from both pre-seizure and seizure-free intervals suggest that despite epilepsy, human cortex operates in the stable, slightly subcritical regime, just like cortex of other healthy mammalians.Comment: 19 pages, 8 Figure