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1.
J Ethnobiol Ethnomed ; 20(1): 41, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575934

RESUMO

BACKGROUND: The complex interplay of social and environmental factors shapes ecosystems, potentially leading to harmony or conflict, highlighting the importance of understanding these dynamics for coexistence. In developing countries, firewood serves as a primary energy source and plays a role in cultural-religious rituals and festivities. However, the specific patterns of woody species used for the latter remain poorly understood, including the impact of access restrictions to resources and local bans on practices. Therefore, our research focuses on examining how access restrictions to forest resources and bonfire bans due to the coronavirus disease 2019 (COVID-19) impact the cultural-religious tradition of bonfire making during Festas Juninas (June festivities) in northeastern Brazil. METHODS: Ethnobotanical fieldwork was conducted in two rural populations in northeastern Brazil between 2021 and 2022. Data were collected through semi-structured interviews, observations, and the guided tour technique. The cultural-religious tradition of bonfire making (i.e., richness of native and exotic firewood species, firewood volume, and the number of bonfires related to this practice) was compared between populations (i.e., differing in access restrictions) and years (i.e., differing in COVID-19-related bans) using Mann-Whitney U tests. RESULTS: Results revealed significant differences in the richness of native (p value = 0.001) and exotic (p value < 0.001) firewood species for bonfire making due to access restrictions to forest resources. The number of native species used was higher among the population residing in the area with unrestricted access than among those with restricted access, while a greater number of exotic species was used in the population with restricted access. The rest of the variables were not influenced by access restrictions, and no variables were influenced by COVID-19 bans. CONCLUSIONS: Our study demonstrated that access restrictions to forest resources, rather than COVID-19 bans, drive the selection of firewood species for bonfires during Festas Juninas in northeastern Brazil. In addition, as populations remain deeply entrenched in cultural-religious practices amid temporary bans imposed by health crises, there is a pressing need for culturally sensitive environmental policies. Fostering socio-ecological resilience demands a comprehensive approach that encompasses not only environmental factors but also cultural dimensions, which wield a pivotal influence on long-term sustainability.


Assuntos
COVID-19 , Ecossistema , Humanos , Brasil , Florestas , Etnobotânica
2.
Microb Ecol ; 86(4): 2252-2270, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37393557

RESUMO

Microbial mats are complex ecological assemblages that have been present in the rock record since the Precambrian and can still be found in extant marginalized environments. These structures are considered highly stable ecosystems. In this study, we evaluate the ecological stability of dome-forming microbial mats in a modern, water-level fluctuating, hypersaline pond located in the Cuatro Ciénegas Basin, Mexico. We conducted metagenomic sampling of the site from 2016 to 2019 and detected 2250 genera of Bacteria and Archaea, with only <20 belonging to the abundant taxa (>1%). The microbial community was dominated by Proteobacteria, Euryarchaeota, Bacteroidetes, Firmicutes, and Cyanobacteria, and was compositionally sensitive to disturbances, leading to high taxonomic replacement even at the phylum level, with a significant increase in Archaea from [Formula: see text]1-4% to [Formula: see text]33% throughout the 2016-2019 study period. Although a core community represented most of the microbial community (>75%), relative abundances shifted significantly between samples, as demonstrated by changes in the abundance of Coleofasciculus from 10.2% in 2017 to 0.05% in 2019. Although functional differences between seasons were subtle, co-occurrence networks suggest differential ecological interactions between the seasons, with the addition of a new module during the rainy season and the potential shift in hub taxa. Functional composition was slightly more similar between samples, but basic processes such as carbohydrate, amino acid, and nucleic acid metabolisms were widely distributed among samples. Major carbon fixation processes included sulfur oxidation, nitrogen fixation, and photosynthesis (both oxygenic and anoxygenic), as well as the Wood-Ljundgahl and Calvin cycles.


Assuntos
Cianobactérias , Microbiota , Metagenoma , Cianobactérias/genética , Archaea/genética , Bacteroidetes/genética
3.
Ambio ; 52(5): 963-975, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36701115

RESUMO

Returning to Earth's safe operating space requires driving social-ecological transformations toward a new human-nature configuration, while navigating changes and creatively dealing with crises. Family farms in the Colombian Andes have been navigating changes by using modalities of integrated management that recognize family interdependence with nature, which illustrates social-ecological resilience on a small scale. We potentiated family farming by creating FiNCO (Farms for knowledge exchange) as a strategy that renews the connection between disciplines, academia and farmers, and the rural and urban sectors, in order to promote knowledge co-production and landscape stewardship. In this sense, FiNCO is considered as a seed for a good Anthropocene. This paper is an invitation to plant FiNCO seeds in different social-ecological contexts and to share those experiences as an ideal way to create abilities to transform the upcoming humanity challenges into opportunities for humanity's needed transformation.


Assuntos
Agricultura , Ecossistema , Humanos , Fazendas , Colômbia , Sementes
5.
Environ Manage ; 68(4): 505-521, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34327556

RESUMO

Cumulative and synergistic impacts from environmental pressures, particularly in low-lying tropical coastal regions, present challenges for the governance of ecosystems, which provide natural resource-based livelihoods for communities. Here, we seek to understand the relationship between responses to the impacts of El Niño and La Niña events and the vulnerability of mangrove-dependent communities in the Caribbean region of Colombia. Using two case study sites, we show how communities are impacted by, and undertake reactive short-term responses to, El Niño and La Niña events, and how such responses can affect their adaptive capacity to progressive environmental deterioration. We show that certain coping measures to climate variability currently deliver maladaptive outcomes, resulting in circumstances that could contribute to system 'lock-in' and engender undesirable ecological states, exacerbating future livelihood vulnerabilities. We highlight the significant role of social barriers on vulnerabilities within the region, including perceptions of state abandonment, mistrust and conflicts with authorities. Opportunities to reduce vulnerability include enhancing the communities' capacity to adopt more positive and preventative responses based on demonstrable experiential learning capacity. However, these will require close cooperation between formal and informal organisations at different levels, and the development of shared coherent adaptation strategies to manage the complexity of multiple interacting environmental and climatic pressures.


Assuntos
Mudança Climática , Ecossistema , Região do Caribe , Colômbia , Emprego , Previsões , Humanos
6.
J Adolesc Health ; 68(3): 580-588, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32919888

RESUMO

PURPOSE: In situations of adversity, young people draw on individual, relational, and contextual (community and cultural) resources to foster their resilience. Recent literature defines resilience as a capacity that is underpinned by a network of interrelated resources. Although empirical studies show evidence of the value of a network approach, little is known regarding how different country contexts influence which resources are most critical within a resource network and how resources interact for adolescent resilience. METHODS: Network analysis was conducted with data from studies that had used the Child and Youth Resilience Measure. Regularized partial correlation networks of 17 resources were estimated for 14 countries (Botswana, Canada, China, Colombia, Equatorial Guinea, India, Indonesia, Italy, Jordan, New Zealand, the Philippines, Romania, South Africa, and Syrian refugees living in Jordan). The sample size was 18,914 (mean age = 15.70 years, 48.8% female). RESULTS: We observed mostly positive associations between the resources of interest. The salience and strength of associations between resources varied by country. The most central resource across countries was having supportive caregivers during stressful times because this resource had the most and strongest positive associations with other resources. CONCLUSIONS: This study gives first empirical evidence from multiple countries that an interplay of social-ecological resources (such as individual skills, peer, caregiver and community support, and educational aspirations and opportunities) matter for adolescent resilience. Across countries, caregiver support appears to be most central for adolescent resilience. Future resilience interventions might apply this network approach to identify important, contextually relevant resources that likely foster additional resources.


Assuntos
Resiliência Psicológica , Adolescente , Botsuana , Canadá , Criança , China , Colômbia , Feminino , Humanos , Índia , Itália , Masculino , Nova Zelândia , África do Sul
7.
Bull Math Biol ; 81(10): 3864-3888, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31471783

RESUMO

Ecological resilience refers to the ability of a system to retain its state when subject to state variables perturbations or parameter changes. While understanding and quantifying resilience is crucial to anticipate the possible regime shifts, characterizing the influence of the system parameters on resilience is the first step toward controlling the system to avoid undesirable critical transitions. In this paper, we apply tools of qualitative theory of differential equations to study the resilience of competing populations as modeled by the classical Lotka-Volterra system. Within the high interspecific competition regime, such model exhibits bistability, and the boundary between the basins of attraction corresponding to exclusive survival of each population is the stable manifold of a saddle point. Studying such manifold and its behavior in terms of the model parameters, we characterized the populations resilience: While increasing competitiveness leads to higher resilience, it is not always the case with respect to reproduction. Within a pioneering context where both populations initiate with few individuals, increasing reproduction of one population leads to an increase in its resilience; however, within an environment previously dominated by one population and then invaded by the other, an increase in the resilience of a population is obtained by decreasing its reproduction rate. Besides providing interesting insights for the dynamics of competing populations, this work brings near to each other the concepts of ecological resilience and the methods of differential equations and stimulates the development and application of new tools for ecological resilience.


Assuntos
Ecossistema , Modelos Biológicos , Adaptação Fisiológica , Animais , Comportamento Competitivo , Espécies Introduzidas , Conceitos Matemáticos , Dinâmica Populacional/estatística & dados numéricos , Biologia de Sistemas
8.
Proc Natl Acad Sci U S A ; 113(3): 793-7, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26711984

RESUMO

Amazon forests, which store ∼ 50% of tropical forest carbon and play a vital role in global water, energy, and carbon cycling, are predicted to experience both longer and more intense dry seasons by the end of the 21st century. However, the climate sensitivity of this ecosystem remains uncertain: several studies have predicted large-scale die-back of the Amazon, whereas several more recent studies predict that the biome will remain largely intact. Combining remote-sensing and ground-based observations with a size- and age-structured terrestrial ecosystem model, we explore the sensitivity and ecological resilience of these forests to changes in climate. We demonstrate that water stress operating at the scale of individual plants, combined with spatial variation in soil texture, explains observed patterns of variation in ecosystem biomass, composition, and dynamics across the region, and strongly influences the ecosystem's resilience to changes in dry season length. Specifically, our analysis suggests that in contrast to existing predictions of either stability or catastrophic biomass loss, the Amazon forest's response to a drying regional climate is likely to be an immediate, graded, heterogeneous transition from high-biomass moist forests to transitional dry forests and woody savannah-like states. Fire, logging, and other anthropogenic disturbances may, however, exacerbate these climate change-induced ecosystem transitions.


Assuntos
Mudança Climática , Ecossistema , Biomassa , Brasil , Desidratação , Tecnologia de Sensoriamento Remoto , Estações do Ano , Solo
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