Tree growth is generally limited by temperature in cold climates and by water availability in arid zones. Establishment in altitudinal treeline ecotones depends on the temperature, but may be very sensitive to water availability as well. We studied the effect of climate and land use on the colonization and growth of Pinus cembra in the treeline ecotone of the dry Central Swiss Alps; one site was influenced by timber harvest and cattle activity and another one was undisturbed. Stands were sampled at three elevations: in the forest and the lower and upper parts of the treeline ecotone. The age structure was similar in all sites, ranging from uneven-aged (forest) to more even-aged, with recent densification and upslope expansion of the treeline ecotone. However, recruitment started at the treeline around 1850 (the end of the Little Ice Age) in the undisturbed site, simultaneously with an increase of tree-ring growth, but about 60 years later at the other site, after cattle grazing decreased. These results, and the positive correlation of radial growth with summer and previous autumn temperatures indicated that, in this altitudinal treeline ecotone, growth and establishment are mainly linked to temperature. However, drought stress was visible in the lowest stands, with a positive correlation of growth with rainfall during the previous autumn and December, and in August of the growing season. This could limit growth in a future warmer climate.
La pandémie due au nouveau coronavirus a frappé la population avec une ampleur exceptionnelle. Afin de combattre la propagation de l’agent pathogène et de préserver les capacités du système de soins en Suisse, les autorités fédérales et cantonales ont adopté une politique sanitaire d’urgence, dans un contexte marqué par d’importantes incertitudes scientifiques. La gestion d’une telle crise donne lieu à des choix de mesures de prévention et de lutte, en fonction des connaissances disponibles. D’éventuels préjudices associés à ces mesures ou à leur insuffisance ouvrent la réflexion sur l’existence d’une responsabilité de l’Etat pour ses actes illicites. Celle-ci se place tant sur le terrain des mesures ordonnées que de l’omission illicite d’en prononcer ; dans ce second cas, l’autorité n’est pas supposée faire tout ce qui possible, mais uniquement ce qui est approprié et raisonnable. -- Die Coronavirus-Pandemie hat die Bevölkerung aussergewöhnlich stark getroffen. Um die Ausbreitung des Erregers zu bekämpfen und die Leistungsfähigkeit des schweizerischen Gesundheitswesens zu erhalten, haben die Behörden des Bundes und der Kantone in einem von erheblicher wissenschaftlicher Unsicherheit geprägten Umfeld eine Notfall-Gesundheitspolitik beschlossen. Die Bewältigung einer solchen Krise führt zu verschiedenen Präventiv- und Kontrollmassnahmen, die jeweils basierend auf dem aktuellen Wissensstand getroffen werden. Mögliche Nachteile, die mit diesen Massnahmen oder deren Unzulänglichkeit verbunden sind, führen den Autor zur Frage der Verantwortung des Staates für seine unerlaubten Handlungen. Dies gilt sowohl für die angeordneten Massnahmen als auch für deren rechtswidrige Unterlassung; im letzteren Fall sollen die Behörden nicht alles Machbare unternehmen, sondern nur das, was geeignet und zumutbar ist.
In September 2015, the European Parliament and the Council adopted a new directive (2015/1513) that amended two existing directives in order to bolster the production of advanced fuels, biofuels, and ``CO2-fuels'' in the transport sector. The combination of carbon dioxide and hydrogen (obtained by means of electrolysis with surpluses of renewable electricity) produces synthetic and renewable fuels that can easily be stored and transported in existing infrastructures. It is also possible to use CO2-enriched microalgae as a feedstock for biofuel. To the extent these advanced fuels can be substituted for fossil energy, they could be helpful in the context of climate mitigation and energy transition, provided the regulatory framework is geared towards such an ambitious purpose. Our comments address the relevance of legislative activity around such a strategy, mainly what kind of legal provisions are already taking shape at the European Union level. We discuss the ability of European directives to manage CO2-fuels and biofuels made from microalgae with CO2 enrichment. This subject is new, and the literature on related legal provisions is rare, thus the need to establish a reader's guide to the existing regulatory framework.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.