Open Access

Zielsetzung: Untersuchung der Auswirkungen der Covid-19-Pandemie auf Angebote der vor allem niedrigschwelligen Drogenhilfe und Reaktionen der Klientel auf geänderte Angebote. Methodik: Verwendet wurden in erster Linie Daten aus einer asynchronen qualitativen Onlinebefragung für Mitarbeiter_innen der ambulanten Drogenhilfe, ergänzt durch Zahlen aus einer quantitativen Onlinebefragung für dieselbe Zielgruppe. Ergebnisse: Während übliche Infektionsschutzmaßnahmen nahezu überall angewendet wurden, reichte die Spanne der tatsächlichen Auswirkungen von Komplettschließungen bis zu eher geringen Einschränkungen. Schwerpunkte wurden zumeist auf Überlebenshilfe und Straßensozialarbeit gelegt. Beratung wurde oft per Telefon durchgeführt, was für viele Anliegen als sinnvoll erachtet wurde, Beziehungsarbeit aber erschwerte. Vor allem stark verelendete Klient_innen nutzten weiterhin häufig Hilfsangebote. Schlussfolgerungen: Es zeigen sich unterschiedliche Umgangsweisen der Drogenhilfe mit den pandemiebedingten Maßnahmen. Oft entwickelte man kreative Lösungen zur Umsetzung, mit Schwerpunktsetzung auf Existenzsicherung. Sowohl Mitarbeiter_innen als auch Klientel waren durch die Pandemie zahlreichen Belastungen ausgesetzt.

Bei der Realisierung der dringend nötigen Verkehrs- und Mobilitätswende sind Möglichkeiten der Befriedung menschlicher Mobilitätsbedürfnisse unabhängig von privater Autonutzung ein wichtiger Baustein. Im Rahmen dieser Arbeit werden darum instrumentelle, affektive und symbolische Motive der privaten Lastenradnutzung qualitativ erforscht. Das Lastenrad hat in den vergangenen Jahren insbesondere in urbanen Räumen an Popularität gewonnen und ermöglicht für den Transport von weiteren Personen, insbesondere Kindern, Tieren oder größeren Lasten eine emissionsarme oder -freie Fortbewegung. Die Untersuchungsergebnisse zeigen, dass bei den instrumentellen Motive die häufig nach Gender verteilte Sorgearbeit eine entscheidende Rolle einnimmt. Dabei erfüllt das Lastenrad das von den Ansprüchen Transportoptionen, Zeitsouveränität, Geschwindigkeit, Erreichbarkeit und Multifunktionalität geprägte Mobilitätsbedürfnis von Personen, die neben Sorge- auch Lohnarbeit im Alltag leisten, im urbanen Raum auf einzigartige Weise. Auch für Personen, deren Alltag nicht maßgeblich durch diese Doppelbelastung geprägt ist, stellt die mit dem Lastenrad mögliche optimierte Überwindung von Raum- und Zeitwiderständen ein relevantes instrumentelles Motiv dar. Hinzu kommen soziale Interaktion, Gesundheit und Klimaschutz. Dabei ist die Lastenradnutzung stark mit positiven emotionalen Reaktionen und hedonischem Erlebniswert verknüpft. Symbolisch drückt sie einen hohen finanziellen und sozialen Status der Besitzer*innen aus und genießt hohes Ansehen in ihrem sozialen Umfeld. Gleichzeitig kann mit der Lastenradnutzung das Bedürfnis nach Individualität und Distinktion erfüllt und der hohe Stellenwert, den nachhaltige Mobilität für die Lastenradbesitzer*innen dieser Untersuchung hat, ausgedrückt werden.

Aim: Recent studies in southern Africa identified past biome stability as an important predictor of biodiversity. We aimed to assess the extent to which past biome stability predicts present global biodiversity patterns, and the extent to which projected climatic changes may lead to eventual biome changes in areas with constant past biome. Location: Global. Taxon: Spermatophyta; terrestrial vertebrates. Methods: Biome constancy was assessed and mapped using results from 89 dynamic global vegetation model simulations, driven by outputs of palaeoclimate experiments spanning the past 140 ka. We tested the hypothesis that terrestrial vertebrate diversity is predicted by biome constancy. We also simulated potential future vegetation, and hence potential future biome patterns, and quantified and mapped the extent of projected eventual future biome change in areas of past constant biome. Results: Approximately 11% of global ice-free land had a constant biome since 140 ka. Apart from areas of constant Desert, many areas with constant biome support high species diversity. All terrestrial vertebrate groups show a strong positive relationship between biome constancy and vertebrate diversity in areas of greater diversity, but no relationship in less diverse areas. Climatic change projected by 2100 commits 46%–66% of global ice-free land, and 34%–52% of areas of past constant biome (excluding areas of constant Desert) to eventual biome change. Main conclusions: Past biome stability strongly predicts vertebrate diversity in areas of higher diversity. Future climatic changes will lead to biome changes in many areas of past constant biome, with profound implications for biodiversity conservation. Some projected biome changes will result in substantial reductions in biospheric carbon sequestration and other ecosystem services.

Oceanic islands only comprise a small amount of the Earth’s land area but harbour a disproportionate amount of global biodiversity. This vast diversity is not only reflected in the taxonomic uniqueness of island biota but also in the remarkable evolution of functional traits. Functional traits, i.e. measurable characteristics that strongly influence the fitness of species, determine how a species responds to its environment and can help to gain more insights into the biogeographical, ecological and evolutionary processes that have shaped island biodiversity. However, research in island biogeography has primarily focused on species richness, and knowledge of functional trait patterns on oceanic islands is scarce. Hence, in this dissertation, I have explored how trait-based approaches can increase our understanding of how biodiversity on oceanic islands assembles and how it is driven by the environment. The Canary Islands (Spain) are a particularly suitable model system to investigate patterns and drivers of biodiversity. The archipelago is characterised by a high variation in environmental heterogeneity and inhabits a unique and well-described native flora. Therefore, I have investigated five principal research questions using the flora (Spermatophytes) of the Canary Islands as a study object. First, I have analysed how climate and biogeography shape the assembly of the Canary Islands flora using a novel trait-based approach. Second, the question of whether rare climates link to functional trait distinctiveness in the native Canary Islands flora was addressed. Third, I have examined how intraspecific trait variation is represented in the native flora of oceanic islands focusing on the succulent scrub of La Palma (Canary Islands). Fourth, this dissertation investigated whether scientific floras can be reliable sources for trait data of plants native to oceanic islands. Finally, I have explored how climate change may impact the native Canary Islands flora by analysing possible climate change-induced shifts in plant species distribution and plant traits. The results of my dissertation expand the understanding of the importance of biogeography and the environment in determining the functional composition of island floras. I have assessed that traits of endemic plant species did not expand the functional trait space of the Canary Islands but were packed with the ones of non-endemic species. This result hints at a trait convergence in endemic species, possibly driven by non-adaptive speciation processes. Moreover, I have evidenced that humidity is a critical driver of functional diversity in native plant assemblages and particularly leads to a high trait convergence in arid environments via environmental filtering. In contrast, alien species have expanded the Canary Islands flora’s functional trait space. I further have shown that in contrast to native species assemblages, alien species assemblages are characterised by an increasing functional diversity with increasing aridity. This contrasting pattern of functional diversity could pose a potential risk to the native flora of the Canary Islands as a low functional diversity is expected to reduce the resilience of species assemblages to the establishment of more functionally diverse alien plant species. However, in this dissertation, I also have revealed that endemic plant species on the Canary Islands show a high intraspecific variation in arid environments, possibly as an adaptation to environmental stress. Intraspecific variation could help endemic plant species have a competitive advantage over alien species and be more resilient to environmental changes. Furthermore, in this dissertation, I have shown that scientific floras and taxonomic monographs could be used to gain information on quantitative functional traits of plants native to oceanic islands. This finding is particularly relevant for advances in trait-based research, as coverage of trait data for oceanic island floras is extremely poor in global trait databases. Hence, for some of the studies included in this dissertation, trait data were retrieved from scientific floras and taxonomic monographs and used to answer novel scientific research questions. Thus, I have used trait data from the literature to analyse the effect of climate change on the range size of plants native to the Canary Islands. Identifying plant species of particular conservation concern is critical on oceanic islands as many island species have limited distributions and small population sizes, and their niche tracking is impeded by insularity. I have revealed that single-island endemic plants gain less and lose more climatically suitable areas than archipelago endemic and non-endemic native plants due to a climate change-induced decrease in precipitation until 2100...

Financial poverty, mobility and social participation are interrelated. This nexus makes old-age poverty a highly relevant issue in terms of transport-related social exclusion in an ageing society. To understand how financial poverty affects older people’s travel practices and how they cope with their limited financial resources, we conducted qualitative interviews with low-income older people (aged 60 and above) in Ronnenberg (Hanover region, Germany). Although all the respondents have comparably limited financial resources, using a practice theory perspective along the elements of materials, competences and meanings (Shove et al., 2012), we identified three different types of low-income older people by their travel practices: (i) active older people with multifaceted social interactions, (ii) neighbourhood-oriented older people with local interactions and (iii) home-centred older people with few social interactions. From our analysis, we conclude that financial poverty shapes each element of low-income older people’s travel practices and thereby increases the risk of transport-related social exclusion: (i) certain materials have to be financed, which is challenging or even impossible due to financial poverty; (ii) meanings of travel practices are strongly linked to other practices, thus, if (also for financial reasons) no or a limited range of destinations are mentioned, travel practices are restricted in their frequency and distance; and (iii) necessary competences to be mobile and engage in social activities despite low financial means seem to be differentially available or - more cautiously formulated – less often utilised by low-income older people, which may lead to them abandoning travel practices and related social activities.