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Traité mondial contre la pollution plastique : en coulisses, le regard des scientifiques français présents
2024
Ghiglione, Jean-François | Colombini, Gabin | Baztan, Juan | Lagarde, Fabienne | Dignac, Marie-France | Mercier-Bonin, Muriel | Reynaud, Stephanie | Olsen, Tara | Cousin, Xavier | Laboratoire d'Océanographie Microbienne (LOMIC) ; Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Observatoire océanologique de Banyuls (OOB) ; Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) | Institut d'écologie et des sciences de l'environnement de Paris (iEES Paris) ; Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Cultures, Environnements, Arctique, Représentations, Climat (CEARC) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS) | Institut des Molécules et Matériaux du Mans (IMMM) ; Le Mans Université (UM)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS) | Neuro-Gastroentérologie & Nutrition (ToxAlim-NGN) ; ToxAlim (ToxAlim) ; Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Ecole Nationale Vétérinaire de Toulouse (ENVT) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Ecole d'Ingénieurs de Purpan (INP - PURPAN) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Ecole Nationale Vétérinaire de Toulouse (ENVT) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Ecole d'Ingénieurs de Purpan (INP - PURPAN) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM) ; Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS) | MARine Biodiversity Exploitation and Conservation - MARBEC (UMR MARBEC) ; Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)
International audience | Pas un mois ne passe sans que la pollution plastique ne fasse l’actualité d’une façon ou d’une autre. Il faut dire que nul écosystème n’échappe à la pollution plastique. En moins d’un siècle, nous avons produit deux fois plus de plastique en masse qu’il n’existe d’animaux sur terre.La majeure partie de ces plastiques deviennent finalement des déchets et contribuent à la saturation d’un système de gestion déjà à bout de souffle. Mais la problématique de la pollution plastique va bien au-delà de la question des déchets mal gérés : les plastiques polluent à toutes les étapes de leur cycle de vie. C’est ainsi qu’ils affectent tous les écosystèmes, du fond des océans jusqu’à l’air que nous respirons, en passant par les sols qui nous nourrissent.Les scientifiques ne cessent d’alerter sur cette pollution qui a conduit à la plastification de notre planète en nuisant profondément à la santé humaine. Ces derniers ont un rôle à jouer dans les négociations internationales, comme à Ottawa (Canada) en avril 2024. Il s’agissait de la quatrième et avant-dernière session de négociation du traité mondial contre la pollution plastique (CIN-4). Depuis, le travail continue jusqu’à la dernière étape pour la finalisation du Traité, en novembre 2024 à Busan, en Corée du Sud.
Afficher plus [+] Moins [-]Identifying manning roughness coefficient using automatic calibration method and simulation of pollution incidents in the Nile River, Egypt
2024
Abouelsaad, Omnia | Hassan, Aziz | Omar, Mohie | Hinkelmann, Reinhard
Study region A reach of the Nile River located between Naga Hammadi barrage and Asyut barrage, Egypt Study focus An accurate representation of hydrodynamics of an important water source helps cope with expected future climate changes, pollution incidents and water quality problems. Here, a comparison between HEC-RAS 1D and TELEMAC-2D model was conducted by identifying different Manning coefficients. Moreover, an automatic calibration using Dual-Annealing optimization method was applied for first time to calibrate the model with non-uniform Manning coefficients. The transport of tracer (pollution) was simulated by computing tracer residence times. Pollution transport scenarios were discussed to draw a picture of pollution incidents which will continue to happen in the future. An equation indicating the relation between flow discharge and residence time was derived to hurriedly help decision makers in water management during sudden pollution incidents. New hydrological insights for the region A model with spatially variable Manning coefficients using TELEMAC-2D was set up and calibrated achieving good accuracyies with average errors of approximately 4 cm and 7 cm between field and simulated water levels for two different discharge scenarios. Moreover, an equation for relation between flow discharge and residence time was derived producing a strong correlation coefficient of 0.95. This study, integrating advanced hydrodynamic models and automatic calibration techniques, provides a robust framework for assessing and managing water resource challenges under varying flow conditions.
Afficher plus [+] Moins [-]Interstate air pollution governance in the United States: Exploring Clean Air Act Section 126
2024
Underwood, Alixandra | Marcantonio, Richard | Wood, Danielle | Crippa, Paola
Air pollution is arguably the most pressing human health concern today, accounting for approximately 7–9 million premature deaths worldwide. In the United States, more than 40% of early deaths caused by air pollution are assessed to be caused by emissions produced by neighboring states. This article examines one of the governance mechanisms used by the U.S. to address this issue: section 126 of the Clean Air Act. Critical factors including case length, evidence used, and case outcome are compiled for the population of section 126 petitions submitted from 2000–2022. This evidence is assessed using comparative case analysis. The findings reinforce two issues with the petition process already identified in the literature–the use of cost as a proxy for significance and the excessive and unclear burden of proof placed on downwind states–adding texture to the latter issue by examining the modeling techniques used by downwind states. This analysis identifies lengthy response timelines as an additional issue and calls to attention the infrequency with which the EPA has formally accepted petitions. Collectively, these issues increase the cost, complexity, and unpredictability of filing a section 126 petition.
Afficher plus [+] Moins [-]State of water quality monitoring and pollution control in Africa: towards developing an African Water Quality Program (AWaQ)
2024
Mukuyu, Patience | Jayathilake, Nilanthi | Tijani, M. | Nikiema, Josiane | Dickens, Chris | Mateo-Sagasta, Javier | Chapman, D. V. | Warner, S.
The African Ministers’ Council on Water (AMCOW) Secretariat committed to design and implement an African Water Quality Program (AWaQ) in its Strategic Operational Plan (2020-2024) considering the guiding frameworks it uses such as the Africa Water Vision 2025, United Nations Sustainable Development Goals (SDGs), and the African Union Agenda 2063: The Africa We Want. AMCOW reached out to the International Water Management Institute (IWMI) to support the development of such a program. AWaQ builds on the rich experiences and lessons learned from past and ongoing regional and subregional water quality initiatives across Africa by different players, including African Union institutions, and the wider members of the World Water Quality Alliance (WWQA), as well as the AMCOW African Water and Sanitation Sector Monitoring and Reporting System (WASSMO). The five phases of developing an African Water Quality Program (AWaQ) are explained in the following papers: 1. State of Water Quality Monitoring and Pollution Control in Africa (phase 1-2) 2. Innovations in Water Quality Monitoring and Management in Africa (phase 3-4) 3. A Framework for an African Water Quality Program (AWaQ) (phase 5) 4. Country Water Quality Profiles This paper is the first from the above list and is a baseline assessment of the status of water quality monitoring and pollution control in Africa, including the capacities available across countries in the region. This assessment considers various past and ongoing initiatives related to water quality monitoring and management, capacity development, and water pollution control and impact mitigation. Key findings of this paper highlight the following: 1. There is an encouraging availability of national water testing laboratory facilities across African countries. Nonetheless, there are weaknesses that require attention to ensure effectiveness and sustainability. 2. Regular and ongoing training is needed to keep up with laboratory testing methodologies. However, we observed a low trend in regular training, which does not augur well for keeping abreast of the best practices in water quality monitoring. In the context of emerging pollutants, training needs to be more regular than is currently experienced. 3. Water quality monitoring and management capacities are patchy. Capacities related to staff training, laboratory infrastructure and monitoring program activities need strengthening. 4. Pollution control mechanisms are facing challenges. Regulatory mechanisms and wastewater treatment technologies—the most widely deployed pollution control solutions—may benefit from more concerted investment, and the political will and financing to boost their effectiveness.
Afficher plus [+] Moins [-]Rubus plicatus Weihe & Nees: resilience to pollution caused by stone quarries
2024
This study aimed to analyze the effect of pollution caused by stone quarries on the morpho-anatomy, biochemistry, and physiology of a medicinal wild bramble Rubus plicatus Weihe & Nees. Samples were collected from two natural protected areas: Iron Gates Natural Park and Jiu Gorge National Park, both located in the southwestern part of Romania, and two unpolluted areas from these parks as background sites. We carried out the following analyses on the collected leaves of this taxon: morphology, micromorphology, anatomy, assimilating pigments, heavy metals (Pb, Ni, Cr, Fe), dry mass, bioactive compounds (total phenols and flavonoids), and antioxidant capacity. The results showed more stomata, higher amounts of assimilating pigments, higher amounts of heavy metals (especially lead), less dry mass, less phenols, and more flavonoids in Rubus plicatus leaves from polluted areas compared to areas without sources of pollution. The increased number of stomata and the amounts of assimilator pigments revealed the mechanisms developed by this species in order to survive in polluted conditions.
Afficher plus [+] Moins [-]Ecosystem service research in the dry subtropics: Current state, temporal changes and drivers of regional variability
2024
Dry subtropical (DST) regions that share similar climatic and topographic conditions exhibit today significant disparities in population density, agricultural intensity, wealth and cultural values. In addition, they are also facing increasing pressures on their natural resources. These attributes collectively shape individuals' varying dependence on natural resources and may influence their perception of ecosystem services (ES). In this study, we conducted a systematic literature review, focusing on the DST regions, to address two main questions: 1) What is the current state, temporal trends and regional variability in scientific research on ES and 2) What are the potential drivers of the variability in ES research? Amongst the 471 publications found in our review, 53% focused on provisioning services, followed nearly equally by cultural (33%) and regulating (30%) services. Only 13% addressed more than one ES category and approximately 33% mentioned economic valuation. Our study reveals that research on ES in the dry subtropics experienced a significant increase from 2005 onwards. Approximately 45% of the publications included the term 'ecosystem service' and its frequency has risen substantially over time. Most publications primarily focus on African dry subtropics (over 60%), followed by South and North American ones. Publications from southern Asia and NE Australia were more scarce. Importantly, we found no clear relationship between the number of publications, publication density or representativeness and the variables used as indicators of human pressure (e.g. population density). Consequently, research efforts in the DST regions appear to be influenced by a diverse range of financial and institutional constraints, international research agendas, as well as the personal interests of researchers, contributing to the idiosyncratic nature of this field.
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