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1.
Materials (Basel) ; 17(2)2024 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-38255591

RESUMEN

This work aims to obtain recycled carbon fibre and develop an application for this new material. The carbon fibres were obtained by recycling aerospace prepreg waste via the pyrolysis process. The recycled fibres were combined with an Araldite LH5052/Aradur LY5053 epoxy resin/hardener system using manual lay-up and vacuum bagging processes. For comparison, the same resin/hardener system was used to produce a composite using commercial carbon fibre. The recycled and commercial composites were subjected to flexural, tensile and Mode I testing. Fracture aspects were analysed via scanning electron microscopy (SEM). The pyrolysis process did not affect the fibre surface as no degradation was observed. The fracture aspect showed a mixture of failure in the recycled composite laminate and interlaminar/translaminar failure near the surface of the commercial composite caused by flexural stress. Flexural and tensile tests showed a loss of mechanical strength due to the recycling process, but the tensile values were twice as high. The sand ladder platform was the project chosen for the development of a product made with recycled carbon fibres. The product was manufactured using the same manufacturing process as the specimens and tested with a 1243 kg car. The method chosen to design, manufacture and test the prototype sand ladder platform made of recycled carbon fibre was appropriate and gave satisfactory results in terms of high mechanical strength to bending and ease of use.

2.
Conserv Biol ; : e14169, 2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37650432

RESUMEN

Protected and conserved areas (PCAs) are key ecosystem management tools for conserving biodiversity and sustaining ecosystem services and social cobenefits. As countries adopt a 30% target for protection of land and sea under the Global Biodiversity Framework of the United Nations Convention on Biological Diversity, a critical question emerging is, which 30%? A risk-based answer to this question is that the 30% that returns the greatest reductions in risks of species extinction and ecosystem collapse should be protected. The International Union for Conservation of Nature (IUCN) Red List protocols provide practical methods for assessing these risks. All species, including humans, depend on the integrity of ecosystems for their well-being and survival. Africa is strategically important for ecosystem management due to convergence of high ecosystem diversity, intense pressures, and high levels of human dependency on nature. We reviewed the outcomes (e.g., applications of ecosystem red-list assessments to protected-area design, conservation planning, and management) of a symposium at the inaugural African Protected Areas Congress convened to discuss roles of the IUCN Red List of Ecosystems in the design and management of PCAs. Recent progress was made in ecosystem assessment, with 920 ecosystem types assessed against the IUCN Red List criteria across 21 countries. Although these ecosystems spanned a diversity of environments across the continent, the greatest thematic gaps were for freshwater, marine, and subterranean realms, and large geographic gaps existed in North Africa and parts of West and East Africa. Assessment projects were implemented by a diverse community of government agencies, nongovernmental organizations, and researchers. The assessments have influenced policy and management by informing extensions to and management of formal protected area networks supporting decision-making for sustainable development, and informing ecosystem conservation and threat abatement within boundaries of PCAs and in surrounding landscapes and seascapes. We recommend further integration of risk assessments in environmental policy and enhanced investment in ecosystem red-list assessment to fill current gaps.


Contribuciones de la Lista Roja de Ecosistemas de la UICN al diseño y manejo basados en riesgos de las áreas conservadas y protegidas en África Resumen Las áreas protegidas y conservadas (APC) son herramientas clave del manejo de ecosistemas para conservar la biodiversidad y mantener los servicios ambientales y los cobeneficios sociales. Conforme los países adoptan un objetivo de 30% para la protección del suelo y el mar bajo el Marco Mundial de Biodiversidad de la Convención sobre la Diversidad Biológica de las Naciones Unidas, surge una pregunta crítica: ¿cuál 30%? Una respuesta basada en riesgos a esta pregunta es que se debe proteger el 30% que rinda la mayor reducción del riesgo de extinción de especies y del colapso del ecosistema. Los protocolos de la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza (UICN) proporcionan métodos prácticos para evaluar estos riesgos. Todas las especies, incluidos los humanos, dependen de la integridad de los ecosistemas para su bienestar y supervivencia. África tiene una importancia estratégica para el manejo de ecosistemas debido a la convergencia de una gran diversidad de ecosistemas, presiones intensas y un nivel elevado de dependencia del humano hacia la naturaleza. Revisamos los resultados (p. ej.: aplicaciones de las valoraciones de las listas rojas de ecosistemas al diseño de áreas protegidas, planeación de la conservación y manejo) de un simposio en el primer Congreso de Áreas Protegidas Africanas convocado para discutir el papel de la Lista Roja de Ecosistemas de la UICN en el diseño y manejo de las APC. Existen avances recientes en la evaluación de los ecosistemas, con 920 tipos de ecosistemas evaluados bajo los criterios de la Lista Roja de la UICN en 21 países. Mientras estos ecosistemas comprenden una diversidad de ambientes en todo el continente, los principales vacíos temáticos los encontramos para los dominios subterráneos, de agua dulce y marina, además de que existe un gran vacío geográfico en el norte de África y en partes del este y oeste africano. Los proyectos de evaluación fueron implementados por una comunidad diversa de agencias gubernamentales, organizaciones no gubernamentales e investigadores. La influencia de las evaluaciones sobre las políticas y el manejo se da con la información que proveen a las extensiones y el manejo de las redes de áreas protegidas formales, el apoyo para la toma de decisiones de desarrollo sustentable y la guía para la conservación de ecosistemas y el abatimiento de amenazas dentro de los límites de las APC y en los paisajes terrestres y marinos adyacentes. Recomendamos una mayor integración de las evaluaciones de riesgo dentro de las políticas ambientales y más inversión para las evaluaciones de lista roja de los ecosistemas cubrir los vacíos existentes.

3.
Mol Ecol Resour ; 23(7): 1641-1655, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37464467

RESUMEN

The coastline of Sub-Saharan Africa hosts highly diverse fish communities of great conservation value, which are also key resources for local livelihoods. However, many costal ecosystems are threatened by overexploitation and their conservation state is frequently unknown due to their vast spatial extent and limited monitoring budgets. Here, we evaluated the potential of citizen science-based eDNA surveys to alleviate such chronic data deficiencies and assessed fish communities in Mozambique using two 12S metabarcoding primer sets. Samples were either collected by scientific personnel or trained community members and results from the two metabarcoding primers were combined using a new data merging approach. Irrespective of the background of sampling personnel, a high average fish species richness was recorded (38 ± 20 OTUs per sample). Individual sections of the coastline largely differed in the occurrence of threatened and commercially important species, highlighting the need for regionally differentiated management strategies. A detailed comparison of the two applied primer sets revealed an important trade-off in primer choice with MiFish primers amplifying a higher number of species but Riaz primers performing better in the detection of threatened fish species. This trade-off could be partly resolved by applying our new data-merging approach, which was especially designed to increase the robustness of multiprimer assessments in regions with poor reference libraries. Overall, our study provides encouraging results but also highlights that eDNA-based monitoring will require further improvements of, for example, reference databases and local analytical infrastructure to facilitate routine applications in Sub-Saharan Africa.


Asunto(s)
Ciencia Ciudadana , ADN Ambiental , Animales , Ecosistema , Código de Barras del ADN Taxonómico/métodos , Biodiversidad , Monitoreo del Ambiente/métodos , Peces/genética , Especies en Peligro de Extinción
4.
Nat Commun ; 11(1): 2072, 2020 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-32350288

RESUMEN

Many nations use ecological compensation policies to address negative impacts of development projects and achieve No Net Loss (NNL) of biodiversity and ecosystem services. Yet, failures are widely reported. We use spatial simulation models to quantify potential net impacts of alternative compensation policies on biodiversity (indicated by native vegetation) and two ecosystem services (carbon storage, sediment retention) across four case studies (in Australia, Brazil, Indonesia, Mozambique). No policy achieves NNL of biodiversity in any case study. Two factors limit their potential success: the land available for compensation (existing vegetation to protect or cleared land to restore), and expected counterfactual biodiversity losses (unregulated vegetation clearing). Compensation also fails to slow regional biodiversity declines because policies regulate only a subset of sectors, and expanding policy scope requires more land than is available for compensation activities. Avoidance of impacts remains essential in achieving NNL goals, particularly once opportunities for compensation are exhausted.

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