Search

An increased interest in the resilience of complex socio-ecological and socio-technical systems has led to a variety of metrics being proposed. An overview of these metrics and their underlying concepts would support identifying useful metrics for applications in science and engineering. This study undertakes a scoping review of resilience metrics for systems straddling the societal, ecological, and technical domains to determine how resilience has been measured, the conceptual differences between the proposed approaches, and how they align with the domains of their case studies. We find that a wide variety of resilience metrics have been proposed in the literature. Conceptually, ten different quantification approaches were identified. Four different disturbance types were observed, including sudden, continuous, multiple, and abruptly ending disturbances. Surprisingly, there is no strong pattern regarding socio-ecological systems being studied using the "ecological resilience" concept and socio-technical systems being studied using the "engineering resilience" concept. As a result, we recommend that researchers use multiple resilience metrics in the same study, ideally following different conceptual approaches, and compare the resulting insights. Furthermore, the used metrics should be mathematically defined, the included variables explained and their units provided, and the chosen functional form justified. [ABSTRACT FROM AUTHOR]

Our ability to deal with external changes is determined by our collective willingness to transform and adopt new technologies. These factors are driven by people's opinion on the change itself and the proposed policies. Humans constantly update their opinion by integrating new information they hear with their values, which helps them make a judgement about that new information. Here, we create an agent-based model that explicitly incorporates the concept of values to explore possible drivers of opinion dynamics. In the model, we explore several factors and perform local and global sensitivity analysis to test their individual and interaction effects. We find that consensus formation in the model is mainly determined by factors related to (1) the amount of stochasticity in the opinion updating procedure and (2) the relative ease with which old links are removed and new links are created. Our results demonstrate how opinions and values may co-evolve. Furthermore, they may help in understanding human responses to new policies such as covid-related restrictions or calls to shift to a more plant-based diet. [ABSTRACT FROM AUTHOR]

In the past, the freshwater snail Theodoxus fluviatilis was abundant in the river Rhine, but was considered to be extinct in the Upper and High Rhine in 2004. We found individuals of T. fluviatilis for the first time at sites in the southern part of the Upper Rhine and High Rhine in 2020, where this species went extinct 16 years ago. There are several distinct haplotypes of this species; some of them occurring in geographically separated regions of Europe. We used mitochondrial DNA (cytochrome c oxidase subunit I, COI) to trace the origin of the newly arrived T. fluviatilis. We examined 269 individuals collected at 29 sites and compared their sequence data with known haplotypes of T. fluviatilis and other species of Theodoxus deposited in GenBank. We also analysed a historical sample from 1995 (collected before the species went extinct), which revealed that the haplotype of the native T. fluviatilis in the High Rhine at that time was F28. In the recent samples, however, we found T. fluviatilis with the haplotypes F31 and "euxinus", which are reported in the Ponto-Caspian region. Both haplotypes are cryptic invaders, colonizing the Rhine via the Rhine-Main-Danube canal and adversely affecting the remaining native populations of T. fluviatilis in Western Europe. Our findings are important for this species management by nature conservation authorities: lineages of endangered species should be preserved and supported, while the spreading of invasive, non-native lineages (or species) should be prevented. [ABSTRACT FROM AUTHOR]