TY - JOUR A1 - Rybski, Diego A1 - Reusser, Dominik Edwin A1 - Winz, Anna-Lena A1 - Fichtner, Christina A1 - Sterzel, Till A1 - Kropp, Jürgen T1 - Cities as nuclei of sustainability? JF - Environment and Planning B: Urban Analytics and City Science N2 - We have assembled CO2 emission figures from collections of urban GHG emission estimates published in peer-reviewed journals or reports from research institutes and non-governmental organizations. Analyzing the scaling with population size, we find that the exponent is development dependent with a transition from super- to sub-linear scaling. From the climate change mitigation point of view, the results suggest that urbanization is desirable in developed countries. Further, we compare this analysis with a second scaling relation, namely the fundamental allometry between city population and area, and propose that density might be a decisive quantity too. Last, we derive the theoretical country-wide urban emissions by integration and obtain a dependence on the size of the largest city. KW - Scaling KW - cities KW - climate change KW - development process KW - allometry Y1 - 2017 U6 - https://doi.org/10.1177/0265813516638340 SN - 2399-8083 SN - 2399-8091 VL - 44 IS - 3 SP - 425 EP - 440 PB - Sage Publ. CY - London ER - TY - JOUR A1 - Noonan, Michael J. A1 - Fleming, Christen H. A1 - Tucker, Marlee A. A1 - Kays, Roland A1 - Harrison, Autumn-Lynn A1 - Crofoot, Margaret C. A1 - Abrahms, Briana A1 - Alberts, Susan C. A1 - Ali, Abdullahi H. A1 - Blaum, Niels T1 - Effects of body size on estimation of mammalian area requirements JF - Conservation Biology N2 - Accurately quantifying species' area requirements is a prerequisite for effective area-based conservation. This typically involves collecting tracking data on species of interest and then conducting home-range analyses. Problematically, autocorrelation in tracking data can result in space needs being severely underestimated. Based on the previous work, we hypothesized the magnitude of underestimation varies with body mass, a relationship that could have serious conservation implications. To evaluate this hypothesis for terrestrial mammals, we estimated home-range areas with global positioning system (GPS) locations from 757 individuals across 61 globally distributed mammalian species with body masses ranging from 0.4 to 4000 kg. We then applied block cross-validation to quantify bias in empirical home-range estimates. Area requirements of mammals <10 kg were underestimated by a mean approximately15%, and species weighing approximately100 kg were underestimated by approximately50% on average. Thus, we found area estimation was subject to autocorrelation-induced bias that was worse for large species. Combined with the fact that extinction risk increases as body mass increases, the allometric scaling of bias we observed suggests the most threatened species are also likely to be those with the least accurate home-range estimates. As a correction, we tested whether data thinning or autocorrelation-informed home-range estimation minimized the scaling effect of autocorrelation on area estimates. Data thinning required an approximately93% data loss to achieve statistical independence with 95% confidence and was, therefore, not a viable solution. In contrast, autocorrelation-informed home-range estimation resulted in consistently accurate estimates irrespective of mass. When relating body mass to home range size, we detected that correcting for autocorrelation resulted in a scaling exponent significantly >1, meaning the scaling of the relationship changed substantially at the upper end of the mass spectrum. KW - allometry KW - animal movement KW - area-based conservation KW - autocorrelation KW - home range KW - kernel density estimation KW - reserve design KW - scaling Y1 - 2019 VL - 34 IS - 4 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Nevill, Alan M. A1 - Negra, Yassine A1 - Myers, Tony D. A1 - Duncan, Michael J. A1 - Chaabene, Helmi A1 - Granacher, Urs T1 - Are Early or Late Maturers Likely to Be Fitter in the General Population? JF - International Journal of Environmental Research and Public Health N2 - The present study aims to identify the optimal body-size/shape and maturity characteristics associated with superior fitness test performances having controlled for body-size, sex, and chronological-age differences. The sample consisted of 597 Tunisian children (396 boys and 201 girls) aged 8 to 15 years. Three sprint speeds recorded at 10, 20 and 30 m; two vertical and two horizontal jump tests; a change-of-direction and a handgrip-strength tests, were assessed during physical-education classes. Allometric modelling was used to identify the benefit of being an early or late maturer. Findings showed that being tall and light is the ideal shape to be successful at most physical fitness tests, but the height-to-weight “shape” ratio seems to be test-dependent. Having controlled for body-size/shape, sex, and chronological age, the model identified maturity-offset as an additional predictor. Boys who go earlier/younger through peak-height-velocity (PHV) outperform those who go at a later/older age. However, most of the girls’ physical-fitness tests peaked at the age at PHV and decline thereafter. Girls whose age at PHV was near the middle of the age range would appear to have an advantage compared to early or late maturers. These findings have important implications for talent scouts and coaches wishing to recruit children into their sports/athletic clubs. KW - youth KW - fitness tests KW - allometry KW - body shape KW - biological age Y1 - 2021 U6 - https://doi.org/10.3390/ijerph18020497 SN - 1660-4601 VL - 18 IS - 2 PB - MDPI CY - Basel ER - TY - JOUR A1 - Ryser, Remo A1 - Häussler, Johanna A1 - Stark, Markus A1 - Brose, Ulrich A1 - Rall, Björn C. A1 - Guill, Christian T1 - The biggest losers: habitat isolation deconsructs complex food webs from top to bottom JF - Proceedings of the Royal Society of London : B, Biological sciences N2 - Habitat fragmentation threatens global biodiversity. To date, there is only limited understanding of how the different aspects of habitat fragmentation (habitat loss, number of fragments and isolation) affect species diversity within complex ecological networks such as food webs. Here, we present a dynamic and spatially explicit food web model which integrates complex food web dynamics at the local scale and species-specific dispersal dynamics at the landscape scale, allowing us to study the interplay of local and spatial processes in metacommunities. We here explore how the number of habitat patches, i.e. the number of fragments, and an increase of habitat isolation affect the species diversity patterns of complex food webs (alpha-,beta-,gamma-, diversities). We specifically test whether there is a trophic dependency in the effect of these two factors on species diversity. In our model, habitat isolation is the main driver causing species loss and diversity decline. Our results emphasize that large-bodied consumer species at high trophic positions go extinct faster than smaller species at lower trophic levels, despite being superior dispersers that connect fragmented landscapes better. We attribute the loss of top species to a combined effect of higher biomass loss during dispersal with increasing habitat isolation in general, and the associated energy limitation in highly fragmented landscapes, preventing higher trophic levels to persist. To maintain trophic-complex and species-rich communities calls for effective conservation planning which considers the interdependence of trophic and spatial dynamics as well as the spatial context of a landscape and its energy availability. KW - food webs KW - allometry KW - bioenergetic model KW - metacommunity dynamics KW - dispersal mortality KW - landscape structure Y1 - 2019 U6 - https://doi.org/10.1098/rspb.2019.1177 SN - 0962-8452 SN - 1471-2954 VL - 286 IS - 1908 PB - Royal Society CY - London ER - TY - JOUR A1 - Wildish, J. A1 - Pavesi, Laura A1 - Ketmaier, Valerio T1 - Talitrid amphipods (Crustacea: Amphipoda: Talitridae) and the driftwood ecological niche a morphological and molecular study JF - Journal of natural history : an international journal of systematics, interactive biology and biodiversity. - London : Taylor & Francis   1.1967 - N2 - Coastal regions of the North East Atlantic and Mediterranean Seas have four known species of driftwood talitrids. Records are extremely scanty, often limited to the type locality and dating to 1950. We were able to study three of them, all belonging to the genus Macarorchestia, using fresh and archived samples including type material. Allometric and molecular analyses support: (1) a close relationship among all the three classically defined Macarorchestia species, (2) Macarorchestia was well separated from non-driftwood taxa, and (3) a putative new driftwood talitrid discovered during this study was not closely related to Macarorchestia. Genetic divergence between the new species and Macarorchestia remyi is as high as the average distance among a number of talitrid species included in the study for comparison. A key is provided to identify all three of the presently known species of Macarorchestia, using morphological characters employed in the allometric study. KW - Macarorchestia remyi KW - Macarorchestia roffensis KW - Macarorchestia martini KW - Driftwood habitat KW - COI-DNA barcoding KW - allometry Y1 - 2012 U6 - https://doi.org/10.1080/00222933.2012.717971 SN - 0022-2933 VL - 46 IS - 43-44 SP - 2677 EP - 2700 PB - Routledge, Taylor & Francis Group CY - Abingdon ER -