Search results for "Clima"

Cycles diurnes de rayonnement solaire et forets en Afrique Centrale.

2018

The sunlightconditions prevailing in Central Africa, and their potential impact on forests traits and functioning, have neverbeen fully explored. Using satellite estimates documenting mostly the period 2005-2013, and accounting forscale interactions between the diurnal and annual cycles, we demonstrate that the seasonality of sunlight levelsstrongly vary across Central Africa forests. Gabon stands out with a main dry season strongly light-deficient,cool and moist. An original map of terra firme forest types developed by CIRAD shows that most of theevergreen forests of Central Africa develop in Gabon. We postulate that despite a mean annual precipitationamount below 2000 mm/yr, the Gabonese …

Protection of Trees against Lightning Strikes as a Measure to Prevent Fires and Loss of Human Life

2021

Lighting strikes have been the catalyst of massive uncontrolled fires in areas of combustible vegetation. In some regions, lightning strikes may be a relatively unusual occurrence (e.g., California), but instead they seem to have become a major contributor to the propagation of wildfires, as a byproduct of climate change. Given such unusual weather, wildfires originating from lightning are an increasing threat. In this paper, the authors discuss the withstand capability of trees against lightning and introduce a proactive approach to prevent wildfires by the deployment of tree lighting protection systems (TLPS) to protect forested areas, where deemed necessary by the tree risk assessment.

Real-time optimization of the key filtration parameters in an AnMBR: Urban wastewater mono-digestion vs. co-digestion with domestic food waste

2018

[EN] This study describes a model-based method for real-time optimization of the key filtration parameters in a submerged anaerobic membrane bioreactor (AnMBR) treating urban wastewater (UWW) and UWW mixed with domestic food waste (FW). The method consists of an initial screening to find out adequate filtration conditions and a real-time optimizer applied to a periodically calibrated filtration model for minimizing the operating costs. The initial screening consists of two statistical analyses: (1) Morris screening method to identify the key filtration parameters; (2) Monte Carlo method to establish suitable initial control inputs values. The operating filtration cost after implementing the…

Persistence in complex systems

2022

Persistence is an important characteristic of many complex systems in nature, related to how long the system remains at a certain state before changing to a different one. The study of complex systems' persistence involves different definitions and uses different techniques, depending on whether short-term or long-term persistence is considered. In this paper we discuss the most important definitions, concepts, methods, literature and latest results on persistence in complex systems. Firstly, the most used definitions of persistence in short-term and long-term cases are presented. The most relevant methods to characterize persistence are then discussed in both cases. A complete literature r…

Évolution du stress gélif et idéotypes de pois d'hiver dans le contexte de changement climatique, à une échelle régionale.

2017

11 pages; International audience; Pea (Pisum sativum L.) is an important crop in temperate regions for its high seed protein concentration that is particularly sensitive to abiotic stresses. The abrupt temperature increase known as the “1987/1988 temperature regime shift” that occurs over Europe is questioning how winter pea will perform in the changing climate. This study assessed the winter frost damage evolution along from 1961 to 2015 in Burgundy-Franche-Comté by using: (1) daily observed and gridded regional temperature data and (2) a validated crop winter frost stress model calibrated for pea. This study shows a global decrease of the frost stress nevertheless resulting from a subtle …

Primo contributo all'estensione di alcune serie climatiche siciliane mediante analisi di serie dendrocronologiche

2008

Overwintering strategies of a boreal small mammal in a changing climate

2015

Interazione fra funghi micorrizici e piante pioniere in ambienti aridi e degradati: il caso di Lampedusa

2019

I microrganismi del suolo sono una componente dominante in diversi ecosistemi sia in termini di diversità che di funzioni. Le simbiosi microbiche radicali in particolare sono state studiate più in dettaglio negli ambienti forestali, dove si è accertato il loro ruolo nell’aumentare la capacità degli alberi di accedere ai nutrienti, sequestrare C dall’atmosfera e resistere agli effetti del cambiamento climatico. Ancora poche informazioni esistono riguardo a queste interazioni in ambienti più aridi e degradati e per le specie pioniere che innescano i processi di successione secondaria. Nell’ambito di un Progetto LIFE finalizzato a mettere a punto tecniche di adattamento al cambiamento climatic…

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

2023

Background: Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods: This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, r…

The behavior of Rare-Earth Elements, Zr and Hf during biologically-mediated deposition of silica-stromatolites and carbonate-rich microbial mats

2015

Abstract Venere Lake, in the Pantelleria Island thermal system (Central Mediterranean Sea) consists of a mix of seawater and hydrothermal volcanic fluids containing high levels of dissolved SiO 2 . Close to the lake's thermal springs, siliceous stromatolites are deposed under high bacterial activity conditions whereas roughly interlaminated Ca-carbonates and microbial mats are widely scattered in the lake. The dissolved REE speciation in lake waters is dominated by [REE(CO 3 ) 2 ] − , [REE(CO 3 )] + and [REE(H 3 SiO 4 )] 2 + complexes. On the contrary the most abundant Zr and Hf species are hydroxyl- and fluoride-complexes. The behavior of REE Zr and Hf in the Venere lake waters is controll…