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2021 ◽  
pp. 1-26
Author(s):  
SZABOLCS NAGY ◽  
FRANK T. BREINER ◽  
MIRA ANAND ◽  
STUART H. M. BUTCHART ◽  
MARTINA FLÖRKE ◽  
...  

Summary Climate change presents a particularly complex challenge in the context of flyway scale conservation of migratory bird species as it requires coordinated action by multiple countries along these species’ migratory routes. Coordinating conservation responses requires understanding the vulnerability of species and their habitats to climate change at the flyway scale throughout each species’ annual cycle. To contribute to such understanding, we used species distribution models to assess the exposure to climate change of waterbird species that are the focus of the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA). We found that the species with the smallest proportion of their current range projected to be climatically suitable by 2050 (those whose distributions respond to changes in water availability but that do not perform synchronised migration) are dispersive species in the Afrotropical biogeographic realm, and migratory species in their breeding season, particularly Arctic breeding waders. These species also have the most limited availability of newly suitable areas. Projections for most other Palearctic migratory waterbird species suggest that losses of suitable areas in their current passage and wintering ranges may be largely offset by new areas becoming climatically suitable. The majority of migratory Palearctic waterbirds in the breeding season and Afrotropical waterbirds are widely dispersed with only a small proportion of their populations currently supported by ‘Critical Sites’ (i.e. sites that are either important for Globally Threatened Species or support 1% of the bioregional population of any waterbird species). This makes it unlikely that climate change adaptation measures focusing only on key sites will be sufficient to counter the predicted range losses. Therefore, climate change adaptation responses should also be implemented at the landscape scale for Afrotropical waterbirds and for breeding populations of Palearctic migrant waterbirds.


Author(s):  
Nikolay V. Baranovskiy ◽  
Geniy V. Kuznetsov ◽  
Tatiana N. Nemova

The natural phenomenon of thunderstorm activity is one of many causes of a forest fire. Thunderstorms cause especially intensive fire danger situations within remote areas and highlands. As a rule, a cloud-to-ground lightning discharge is the fire source. The present study is based on the research results of electrical overloads in supply networks. Physical and mathematical formulation and numerical solution for the problem of a coniferous tree (pine) ignited by a cloud-to-ground lightning discharge are presented. The problem is considered in a cylindrical coordinate system in two-dimensional formulation. The features of current passage and heat transfer taking into account the reactive wood localization are investigated. The Joule-Lenz’s law is used to calculate heat production in a tree trunk. Parametric analysis has been conducted and tree trunk ignition conditions have been determined in a typical range for the influencing parameters of negative and positive discharges.


2017 ◽  
Vol 48 (1) ◽  
pp. 12-20
Author(s):  
Mauro Podrecca ◽  
Alessandro Chiumenti ◽  
Francesco Da Borso ◽  
Marco Contin ◽  
Maria De Nobili

Swine livestock farms represent potential sources of emissions of gaseous compounds and odors in relation to slurry management, manure treatment, and particularly, storage. Electrolytic treatments of slurries were proposed to solve this pressing problem. Electrolytic treatment consists of the passage of a low electric current through the liquid phase of swine manure in storage basins determined by two or more electrodes with alternated polarisation. We investigated the mechanisms of odour reduction and evaluated the effects of current intensity and of anodically dissolved copper (Cu2+) ions. Fresh swine slurry was subject to electrolytic treatment in a bench top experiment, at 25 mA and 75 mA for 32 days with either copper or graphite electrodes. Emissions of methane, hydrogen sulphide, and volatile fatty acids were measured. Effects of copper addition to fresh swine slurry were also monitored in a bench top scale trial. Reduction of emissions was found to be due to both current passage and copper dissolution. Reduction of foul emissions in graphite electrodes assays resulted lower than in copper electrodes assays, although the direct additions of Cu2+ ions had a much larger effect than could be predicted from the results of electrolytic treatments with copper electrodes, probably due to the greater uniformity in distribution in swine manure. A simple empiric odour threshold value normalised index, odour offensiveness index of slurries, was found to be effective in differentiating treatments.


2016 ◽  
Vol 28 (1) ◽  
pp. 60-82 ◽  
Author(s):  
Sylvie Droit-Volet

This study examined whether the acceleration of the passage of time as people get older increases after 75 years of age. Individuals older and younger than 75 years, living either at home or in an institution, were asked to provide retrospective judgments of the passage of long periods of time, as well as judgments of the current passage of time using the Experience Sampling Methodology, in which a series of alerts are delivered everyday by mobile phone. The results showed that the retrospective judgment of the passage of time did not change with age. However, the older participants living in a retirement home, who were more negatively focused on their past, disagreed with the idea that time passes faster with increasing age. By contrast, the judgment of the current passage of time changed after 75 years. However, the perception was not one of acceleration but of slowing down. The best predictors of this slowing down of time were the negative affects, namely sadness, which were particularly high among the participants living in a retirement home. However, as their cognitive functions declined, they perceived time as passing quickly again, and this was accompanied by a greater feeling of happiness.


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