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Mediterranean ecosystems are particularly vulnerable to climate change and the associated increase in climate anomalies. This study investigates extreme ecosystem responses evoked by climatic drivers in the Mediterranean Basin for the time span 1999–2019 with a specific focus on seasonal variations as the seasonal timing of climatic anomalies is considered essential for impact and vulnerability assessment. A bivariate vulnerability analysis is performed for each month of the year to quantify which combinations of the drivers temperature (obtained from ERA5-Land) and soil moisture (obtained from ESA CCI and ERA5-Land) lead to extreme reductions in ecosystem productivity using the fraction of absorbed photosynthetically active radiation (FAPAR; obtained from the Copernicus Global Land Service) as a proxy.
The bivariate analysis clearly showed that, in many cases, it is not just one but a combination of both drivers that causes ecosystem vulnerability. The overall pattern shows that Mediterranean ecosystems are prone to three soil moisture regimes during the yearly cycle: they are vulnerable to hot and dry conditions from May to July, to cold and dry conditions from August to October, and to cold conditions from November to April, illustrating the shift from a soil-moisture-limited regime in summer to an energy-limited regime in winter. In late spring, a month with significant vulnerability to hot conditions only often precedes the next stage of vulnerability to both hot and dry conditions, suggesting that high temperatures lead to critically low soil moisture levels with a certain time lag. In the eastern Mediterranean, the period of vulnerability to hot and dry conditions within the year is much longer than in the western Mediterranean. Our results show that it is crucial to account for both spatial and temporal variability to adequately assess ecosystem vulnerability. The seasonal vulnerability approach presented in this study helps to provide detailed insights regarding the specific phenological stage of the year in which ecosystem vulnerability to a certain climatic condition occurs.
How to cite.
Vogel, J., Paton, E., and Aich, V.: Seasonal ecosystem vulnerability to climatic anomalies in the Mediterranean, Biogeosciences, 18, 5903–5927, https://doi.org/10.5194/bg-18-5903-2021, 2021.
Dieser Artikel adressiert zwei bisher nur wenig untersuchte Aspekte der Führungsforschung: Führungsverhalten im öffentlichen Sektor und Faktoren die Führungsverhalten beeinflussen. Mittels einer Fallstudie in der Bundesagentur für Arbeit werden explorativ Hypothesen über Einflussfaktoren des Führungsverhaltens aufgestellt. Die Studie kommt zu der Erkenntnis, dass eine oftmals angenommene Führungslücke im öffentlichen Sektor nicht bestätigt werden kann. Für das ausgeprägte Führungsverhalten, das in der Fallstudie beobachtet wurde, wird als Determinante die besondere Ausgestaltung des Managementsystems der Bundesagentur für Arbeit verantwortlich gemacht. Dazu gehört unter anderem das Performance Management System sowie die Führungskräfteauswahl und -entwicklung. Die Arbeit schließt mit Empfehlungen für weitere Forschungsansätze auf dem Gebiet der Führungsforschung im öffentlichen Sektor.
This article is a response to calls in prior research that we need more longitudi-nal analyses to better understand the foundations of PSM and related prosocial values. There is wide agreement that it is crucial for theory-building but also for tailoring hiring practices and human resource development programs to sort out whether PSM-related values are stable or developable. The article summarizes existent theoretical expecta-tions, which turn out to be partially conflicting, and tests them against multiple waves of data from the German Socio-Economic Panel Study which covers a time period of sixteen years. It finds that PSM-related values of public employees are stable rather than dynamic but tend to increase with age and decrease with organizational member-ship. The article also examines cohort effects, which have been neglected in prior work, and finds moderate evidence that there are differences between those born during the Second World War and later generations.
In response to the impending spread of COVID-19, universities worldwide abruptly stopped face-to-face teaching and switched to technology-mediated teaching. As a result, the use of technology in the learning processes of students of different disciplines became essential and the only way to teach, communicate and collaborate for months. In this crisis context, we conducted a longitudinal study in four German universities, in which we collected a total of 875 responses from students of information systems and music and arts at four points in time during the spring–summer 2020 semester. Our study focused on (1) the students’ acceptance of technology-mediated learning, (2) any change in this acceptance during the semester and (3) the differences in acceptance between the two disciplines. We applied the Technology Acceptance Model and were able to validate it for the extreme situation of the COVID-19 pandemic. We extended the model with three new variables (time flexibility, learning flexibility and social isolation) that influenced the construct of perceived usefulness. Furthermore, we detected differences between the disciplines and over time. In this paper, we present and discuss our study’s results and derive short- and long-term implications for science and practice.
Recent studies have claimed the existence of very massive stars (VMS) up to 300 M⊙ in the local Universe. As this finding may represent a paradigm shift for the canonical stellar upper-mass limit of 150 M⊙, it is timely to discuss the status of the data, as well as the far-reaching implications of such objects. We held a Joint Discussion at the General Assembly in Beijing to discuss (i) the determination of the current masses of the most massive stars, (ii) the formation of VMS, (iii) their mass loss, and (iv) their evolution and final fate. The prime aim was to reach broad consensus between observers and theorists on how to identify and quantify the dominant physical processes.
Anomalous diffusion or, more generally, anomalous transport, with nonlinear dependence of the mean-squared displacement on the measurement time, is ubiquitous in nature. It has been observed in processes ranging from microscopic movement of molecules to macroscopic, large-scale paths of migrating birds. Using data from multiple empirical systems, spanning 12 orders of magnitude in length and 8 orders of magnitude in time, we employ a method to detect the individual underlying origins of anomalous diffusion and transport in the data. This method decomposes anomalous transport into three primary effects: long-range correlations (“Joseph effect”), fat-tailed probability density of increments (“Noah effect”), and nonstationarity (“Moses effect”). We show that such a decomposition of real-life data allows us to infer nontrivial behavioral predictions and to resolve open questions in the fields of single-particle tracking in living cells and movement ecology.
Frailty is a geriatric syndrome characterised by a vulnerability status associated with declining function of multiple physiological systems and loss of physiological reserves. Two main models of frailty have been advanced: the phenotypic model (primary frailty) or deficits accumulation model (secondary frailty), and different instruments have been proposed and validated to measure frailty. However measured, frailty correlates to medical outcomes in the elderly, and has been shown to have prognostic value for patients in different clinical settings, such as in patients with coronary artery disease, after cardiac surgery or transvalvular aortic valve replacement, in patients with chronic heart failure or after left ventricular assist device implantation.
The prevalence, clinical and prognostic relevance of frailty in a cardiac rehabilitation setting has not yet been well characterised, despite the increasing frequency of elderly patients in cardiac rehabilitation, where frailty is likely to influence the onset, type and intensity of the exercise training programme and the design of tailored rehabilitative interventions for these patients.
Therefore, we need to start looking for frailty in elderly patients entering cardiac rehabilitation programmes and become more familiar with some of the tools to recognise and evaluate the severity of this condition. Furthermore, we need to better understand whether exercise-based cardiac rehabilitation may change the course and the prognosis of frailty in cardiovascular patients.
Feeling Half-Half?
(2018)
Growing up in multicultural environments, Turkish-heritage individuals in
Europe face specific challenges in combining their multiple cultural iden-
tities to form a coherent sense of self. Drawing from social identity com-
plexity, this study explores four modes of combining cultural identities and
their variation in relational contexts. Problem-centered interviews with
Turkish-heritage young adults in Austria revealed the preference for com-
plex, supranational labels, such as multicultural. Furthermore, most partici-
pants described varying modes of combining cultural identities over time
and across relational contexts. Social exclusion experiences throughout
adolescence related to perceived conflict of cultural identities, whereas
multicultural peer groups supported perceived compatibility of cultural
identities. Findings emphasize the need for complex, multidimensional
approaches to study ethnic minorities’ combination of cultural identities.
Peer cultural socialisation
(2019)
This study investigated how peers can contribute to cultural minority students’ cultural identity, life satisfaction, and school values (school importance, utility, and intrinsic values) by talking about cultural values, beliefs, and behaviours associated with heritage and mainstream culture (peer cultural socialisation). We further distinguished between heritage and mainstream identity as two separate dimensions of cultural identity. Analyses were based on self-reports of 662 students of the first, second, and third migrant generation in Germany (Mean age = 14.75 years, 51% female). Path analyses revealed that talking about heritage culture with friends was positively related to heritage identity. Talking about mainstream culture with friends was negatively associated with heritage identity, but positively with mainstream identity as well as school values. Both dimensions of cultural identity related to higher life satisfaction and more positive school values. As expected, heritage and mainstream identity mediated the link between peer cultural socialisation and adjustment outcomes. Findings highlight the potential of peers as socialisation agents to help promote cultural belonging as well as positive adjustment of cultural minority youth in the school context.