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1.
Ecol Evol ; 14(7): e70048, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39041018

RESUMO

The Peruvian Province, from 6° S in Peru to 42° S in Chile, is a highly productive coastal marine region whose biology and fossil record have long been studied separately but never integrated. To understand how past events and conditions affected today's species composition and interactions, we examined the role of extinction, colonization, geologic changes to explain previously unrecognized peculiar features of the biota and to compare the Peruvian Province's history to that of other climatically similar temperate coasts. We synthesized all available data on the benthic (or benthically feeding) biota, with emphasis on fossilizable taxa, for the interval from the Miocene (23-5.4 Ma) and Pliocene (5.4-2.5 Ma) to the present. We outline the history of ecological guilds including primary producers, herbivores, predators, and suspension-feeders and document patterns of extinction, colonization, and geographic restriction. We identify twelve unusual attributes of the biota, most of which are the result of repeated episodes of extinction. Several guilds present during the Miocene and Pliocene are not represented in the province today, while groups such as kelps and perhaps intertidal predatory sea stars are relative newcomers. Guilds on soft bottoms and in sheltered habitats were severely affected by extinction, whereas those on hard bottoms were most affected by colonists and held their own in diversity. The Peruvian Province has not served as a biogeographic refuge, in contrast to the coasts of Australasia and Argentina, where lineages no longer present in the Peruvian Province survive. The loss of sheltered habitats since the Pliocene explains many of the present-day peculiarities of the biota. The history of the province's biota explains its unique attributes. High productivity, a rich Southern Hemisphere heritage, and colonization from the north account for the present-day composition and unusual characteristics of the biota.

2.
Pest Manag Sci ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38923386

RESUMO

BACKGROUND: Resistance management in pesticide use is critical, yet grower practices, especially pesticide mixing motivations, diverge from theoretical frameworks. This study analyzes 30 years of Arizona cotton growers' practices and pest manager insights to understand mixing trends. RESULTS: Growers predominantly mix pesticides for spectrum or efficacy, not resistance management. This highlights a gap between theory and practice, emphasizing the complexity of real-world dynamics. A shift over time towards selective insecticides and integrated pest management (IPM), supported by extension education, has reduced reliance on broad-spectrum insecticides and increased opportunities to conserve the natural enemies of key pests. This reduced the frequency of insecticide use, a mutual goal of both IPM and resistance management. The availability and adoption of selective products with diverse modes of action, along with the resulting increases in biological control and refuges, likely has delayed or prevented resistances without emphasis on using mixtures specifically for resistance management. In a disrupted system exclusively dependent on broad-spectrum insecticides (1991-1995), 75% ± 5% of cotton area was sprayed with mixtures of these materials. With the availability of selective insecticides, few broad-spectrum products are used today and mixtures of insecticides are sprayed on only 36% ± 3% of the cotton area (2015-2020). CONCLUSION: Although mixing has theoretical relevance, it is diminishing in stable systems with diverse modes of action and adherence to moderation principles. Arizona cotton guidance prioritizes multi-crop refuges over mixtures for resistance management. Integrated research and education, targeting professional pest managers, are pivotal in advancing resistance management without mixtures specifically designed to prevent or mitigate resistance. © 2024 Society of Chemical Industry.

3.
Sci Total Environ ; 918: 170786, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38331273

RESUMO

Longer durations of warmer weather, altered precipitation, and modified streamflow patterns driven by climate change are expected to impair ecosystem resilience, exposing freshwater ecosystems and their biota to a severe threat worldwide. Understanding the spatio-temporal temperature variations and the processes governing thermal heterogeneity within the riverscape are essential to inform water management and climate adaptation strategies. We combined UAS-based imagery data of aquatic habitats with meteorological, hydraulic, river morphology and water quality data to investigate how key factors influence spatio-temporal stream heterogeneity on a diurnal basis within different thermal regions of a large recently restored Danube floodplain. Diurnal temperature ranges of aquatic habitats were larger than expected and ranged between 14.2 and 28.0 °C (mean = 20.7 °C), with peak median temperatures (26.1 °C) around 16:00 h. The observed temperature differences in timing and amplitude among thermal regions were unexpectedly high and created a mosaic pattern of temperature heterogeneity. For example, cooler groundwater-influenced thermal regions provided several cold water patches (CWP, below 19.0 °C) and potential cold water refuges (CWRs) around 12:00 h, at the time when other habitats were warmer than 21.0 °C, exceeding the ecological threshold (20.0 °C) for key aquatic species. Within the morphological complexity of the restored floodplain, we identified groundwater influence, shading and river morphology as the key processes driving thermal riverscape heterogeneity. Promoting stream thermal refuges will become increasingly relevant under climate change scenarios, and river restoration should consider both measures to physically prevent habitat from excessive warming and measures to improve connectivity that meet the temperature requirements of target species for conservation. This requires restoring mosaics of complex and dynamic temperature riverscapes.

4.
Trends Ecol Evol ; 39(6): 585-598, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38413283

RESUMO

The function and stability of mesophotic coral ecosystems (MCEs) have been extensively studied in recent years. These deep reefs are characterized by local physical processes, particularly the steep gradient in irradiance with increasing depth, and their impact on trophic resources. Mesophotic reefs exhibit distinct zonation patterns that segregate shallow reef biodiversity from ecologically unique deeper communities of endemic species. While mesophotic reefs are hypothesized as relatively stable refuges from anthropogenic stressors and a potential seed bank for degraded shallow reefs, these are site-specific features, if they occur at all. Mesophotic reefs are now known to be susceptible to many of the same stressors that are degrading shallow reefs, suggesting that they require their own specific conservation and management strategies.


Assuntos
Antozoários , Biodiversidade , Conservação dos Recursos Naturais , Recifes de Corais , Animais , Antozoários/fisiologia , Ecossistema
5.
BMC Psychol ; 12(1): 62, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326883

RESUMO

BACKGROUND: Refugee populations are forcibly displaced from their homes as a consequence of natural disasters and armed conflicts. Eritreans, initially displaced to the Maiayni camp within the Tigray region, have faced further relocation to Dabat town due to the conflict between the Tigray People Liberation Front (TPLF) and Ethiopian government forces. Subsequently, another conflict has arisen between the Amhara Popular Force (Fano) and Ethiopian government forces in Dabat town, disrupting its stability. These collective challenges in the new environment may contribute to the development of symptoms such as posttraumatic stress disorder (PTSD), anxiety, and depression. Currently, there is a lack of available data on these symptoms and their associated variables in Dabat Town. Thus, the objective of this study was to assess the prevalence of PTSD, anxiety, and depression symptoms, along with associated factors, among Eritrean refugees in Dabat town, northwest Ethiopia. This will provide significant evidence for developing and implementing mental health intervention strategies that specifically address the particular difficulties faced by refugees. METHOD: A community-based cross-sectional study was carried out from July 25 to September 30, 2023, in the Eritrean refugee camp in Dabat town. A systematic random sampling method was employed to select a total of 399 Eritrean refugees with 100 response rate. Data were collected using the standard validated Depression, Anxiety, and Stress Scale (DASS-21) questionnaire, which included socio-demographic characteristics. Summary statistics such as frequency and proportion were utilized to present the data in tables and figures. Binary logistic regression was employed to identify associated factors, and variables with a p-value (p ≤ 0.05) were considered statistically significant factors. RESULT: The findings of this study indicated that 45% (95% CI: 35.6-48.23), 33.6% (95% CI: 31.66-37.45), and 37.3% (95% CI: 35.56-40.34) of the participants had symptoms of depression, anxiety, and PTSD, respectively. Sex, age, employment status, lack of food or water, experience of torture or beating, and imprisonment emerged as statistically significant predictors of depression. Employment status, murder of family or friends, rape or sexual abuse, torture or beating, and lack of housing or shelter were statistically significantly associated with anxiety. PTSD was found to be significantly associated with sex, length of stay at the refugee camp, lack of housing, shelter, food, or water, experience of rape or sexual abuse, abduction, employment status, and murder of family or friends. CONCLUSIONS AND RECOMMENDATION: The results of this study revealed that more than one-third of Eritreans living in the refugee camp in Dabat town had symptoms of PTSD, anxiety, and depression. This prevalence is higher than the previously reported studies. Various factors, including age, gender, monthly income, unemployment, experiences of rape or sexual abuse, witnessing the murder of family or friends, being torched or beaten, imprisonment, and deprivation of basic needs such as food, shelter, and water, were identified as contributors to the development of depression, anxiety, and PTSD. This research underscores the need for both governmental and non-governmental organizations to secure the provision of essential necessities such as food, clean water, shelter, clothing, and education. This study also suggested that Eritrean refugees be legally protected from rape, sexual abuse, arson, detention without cause, and kidnapping. Moreover, the study calls for health service providers to develop a mental health intervention plan and implement strategies to deliver mental health services at healthcare facilities for Eritrean refugees in the Dabat town Eritrean refugee camp.


Assuntos
População da África Oriental , Refugiados , Transtornos de Estresse Pós-Traumáticos , Humanos , Ansiedade/epidemiologia , Estudos Transversais , Depressão/psicologia , Eritreia/epidemiologia , Etiópia/epidemiologia , Refugiados/psicologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia
6.
AIDS Behav ; 28(2): 507-523, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38048017

RESUMO

Food insecurity (FI) and water insecurity (WI) are linked with HIV vulnerabilities, yet how these resource insecurities shape HIV prevention needs is understudied. We assessed associations between FI and WI and HIV vulnerabilities among urban refugee youth aged 16-24 in Kampala, Uganda through individual in-depth interviews (IDI) (n = 24), focus groups (n = 4), and a cross-sectional survey (n = 340) with refugee youth, and IDI with key informants (n = 15). Quantitative data was analysed via multivariable logistic and linear regression to assess associations between FI and WI with: reduced pandemic sexual and reproductive health (SRH) access; past 3-month transactional sex (TS); unplanned pandemic pregnancy; condom self-efficacy; and sexual relationship power (SRP). We applied thematic analytic approaches to qualitative data. Among survey participants, FI and WI were commonplace (65% and 47%, respectively) and significantly associated with: reduced SRH access (WI: adjusted odds ratio [aOR]: 1.92, 95% confidence interval [CI]: 1.19-3.08; FI: aOR: 2.31. 95%CI: 1.36-3.93), unplanned pregnancy (WI: aOR: 2.77, 95%CI: 1.24-6.17; FI: aOR: 2.62, 95%CI: 1.03-6.66), and TS (WI: aOR: 3.09, 95%CI: 1.22-7.89; FI: aOR: 3.51, 95%CI: 1.15-10.73). WI participants reported lower condom self-efficacy (adjusted ß= -3.98, 95%CI: -5.41, -2.55) and lower SRP (adjusted ß= -2.58, 95%CI= -4.79, -0.37). Thematic analyses revealed: (1) contexts of TS, including survival needs and pandemic impacts; (2) intersectional HIV vulnerabilities; (3) reduced HIV prevention/care access; and (4) water insecurity as a co-occurring socio-economic stressor. Multi-method findings reveal FI and WI are linked with HIV vulnerabilities, underscoring the need for HIV prevention to address co-occurring resource insecurities with refugee youth.


Assuntos
COVID-19 , Infecções por HIV , Refugiados , Adolescente , Feminino , Humanos , Gravidez , Estudos Transversais , Insegurança Alimentar , Abastecimento de Alimentos , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Uganda/epidemiologia , Insegurança Hídrica , Adulto Jovem
7.
Rev. biol. trop ; 71(1)dic. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1449517

RESUMO

Introducción: La presencia y estructura de la vegetación en áreas urbanas tiene un impacto en la composición de las comunidades de aves. Las áreas verdes con una mayor proporción de vegetación introducida tienden a presentar una homogeneización de avifauna, mientras que las áreas verdes con alta proporción de vegetación nativa presentan mayor diversidad de aves. En varios trabajos realizados en áreas urbanas de México, estos factores no son tomados en cuenta. Por lo tanto, se desconocen las respuestas de las especies en términos de riqueza y diversidad. Objetivo: Analizar la composición de especies de aves en las áreas verdes de Ciudad Victoria, Tamaulipas y evaluar la respuesta de las comunidades de aves en tres áreas verdes con diferente composición de vegetación. Así como analizar la relación entre los gremios tróficos de aves con los elementos de la vegetación en las áreas urbanas. Métodos: El estudio se llevó a cabo en tres sitios de muestreo de Ciudad Victoria, Tamaulipas, México, con base en dos criterios: área similar de muestreo (ha) y diferencias en las características de la vegetación. Los monitoreos se realizaron de enero a diciembre de 2020, con tres visitas mensuales en cada sitio para un total de 108 visitas, utilizando el método visual directo. Resultados: Identificamos 98 especies (11 órdenes, 28 familias). Las especies más abundantes fueron Quiscalus mexicanus y Molothrus aeneus. Hubo diferencias en la riqueza de especies para cada sitio. Las insectívoras y granívoras fueron las dominantes. Se determinó una asociación entre los gremios y los sitios de estudio, donde la mayoría están relacionados con la vegetación mixta, comparado con la vegetación homogénea o introducida. Conclusiones: Las áreas urbanas estudiadas mantuvieron un número notable de aves, y varias de ellas presentaron alguna categoría de riesgo o endemismo. Esto demuestra la importancia de estas áreas verdes como refugio de aves y resalta la necesidad de conservar y proteger dichas áreas dentro de Ciudad Victoria y ciudades similares.


Introduction: The presence and structure of vegetation in urban areas have an impact on the composition of bird communities. Green areas with a higher ratio of introduced vegetation tend to have a greater homogenization of avifauna, whereas green areas with a high ratio of native vegetation have a greater diversity of birds. In several studies carried out in urban areas of Mexico, the factors of vegetation are not considered. Therefore, the responses of the species to vegetation types in terms of richness and diversity are unknown. Objective: To analyze the composition of bird species in the green areas of Ciudad Victoria, Tamaulipas, and evaluate the response of bird communities in areas with differences in vegetation composition. As well as to analyze the relationship between the trophic guilds in birds and vegetation in urban areas. Methods: Three sampling sites were established in Ciudad Victoria, Tamaulipas, Mexico, based on two criteria: similar sampling area (ha) and differences in vegetation characteristics. Monitoring took place between January and December 2020, with three monthly visits in each site for a total of 108 visits, using the direct visual method. Results: We identified 98 species (11 orders, 28 families). The most abundant species were Quiscalus mexicanus and Molothrus aeneus. Differences in species richness were found for each site. The insectivorous and granivorous were the dominant guilds. An association between the guilds and the study sites was determined, where most were linked to mixed native vegetation, compared to homogeneous or introduced vegetation. Conclusions: The urban areas studied maintained a notable number of birds, and several of them presented some category of risk or endemism. This demonstrates the importance of these green areas composed of native vegetation as a refuge for birds and highlights the need to conserve and protect these areas within Ciudad Victoria and similar cities.

8.
Ecol Evol ; 13(11): e10632, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37953991

RESUMO

Migratory waterfowl are an important resource for consumptive and non-consumptive users alike and provide tremendous economic value in North America. These birds rely on a complex matrix of public and private land for forage and roosting during migration and wintering periods, and substantial conservation effort focuses on increasing the amount and quality of target habitat. Yet, the value of habitat is a function not only of a site's resources but also of its geographic position and weather. To quantify this value, we used a continental-scale energetics-based model of daily dabbling duck movement to assess the marginal value of lands across the contiguous United States during the non-breeding period (September to May). We examined effects of eliminating each habitat node (32 × 32 km) in both a particularly cold and a particularly warm winter, asking which nodes had the largest effect on survival. The marginal value of habitat nodes for migrating dabbling ducks was a function of forage and roosting habitat but, more importantly, of geography (especially latitude and region). Irrespective of weather, nodes in the Southeast, central East Coast, and California made the largest positive contributions to survival. Conversely, nodes in the Midwest, Northeast, Florida, and the Pacific Northwest had consistent negative effects. Effects (positive and negative) of more northerly nodes occurred in late fall or early spring when climate was often severe and was most variable. Importance and effects of many nodes varied considerably between a cold and a warm winter. Much of the Midwest and central Great Plains benefited duck survival in a warm winter, and projected future warming may improve the value of lands in these regions, including many National Wildlife Refuges, for migrating dabbling ducks. Our results highlight the geographic variability in habitat value, as well as shifts that may occur in these values due to climate change.

9.
Glob Chang Biol ; 29(19): 5482-5508, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37466251

RESUMO

Human activities and climate change threaten coldwater organisms in freshwater ecosystems by causing rivers and streams to warm, increasing the intensity and frequency of warm temperature events, and reducing thermal heterogeneity. Cold-water refuges are discrete patches of relatively cool water that are used by coldwater organisms for thermal relief and short-term survival. Globally, cohesive management approaches are needed that consider interlinked physical, biological, and social factors of cold-water refuges. We review current understanding of cold-water refuges, identify gaps between science and management, and evaluate policies aimed at protecting thermally sensitive species. Existing policies include designating cold-water habitats, restricting fishing during warm periods, and implementing threshold temperature standards or guidelines. However, these policies are rare and uncoordinated across spatial scales and often do not consider input from Indigenous peoples. We propose that cold-water refuges be managed as distinct operational landscape units, which provide a social and ecological context that is relevant at the watershed scale. These operational landscape units provide the foundation for an integrated framework that links science and management by (1) mapping and characterizing cold-water refuges to prioritize management and conservation actions, (2) leveraging existing and new policies, (3) improving coordination across jurisdictions, and (4) implementing adaptive management practices across scales. Our findings show that while there are many opportunities for scientific advancement, the current state of the sciences is sufficient to inform policy and management. Our proposed framework provides a path forward for managing and protecting cold-water refuges using existing and new policies to protect coldwater organisms in the face of global change.


Assuntos
Ecossistema , Rios , Humanos , Água Doce , Temperatura Baixa , Mudança Climática , Água
10.
BMC Zool ; 8(1): 1, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-37170169

RESUMO

Amphibians are facing population declines and extinctions, and protecting and supplementing refuges can help species survive. However, the microhabitat requirements of most species are unknown, and artificial shelters or burrows have not been well tested for amphibians. Some amphibians exhibit complex behaviour during the transition from post-reproductive dormancy to activity. However, little is known about the ecology, post-reproductive dormancy, and terrestrial activity of amphibians. Here, habitat site selection in experimental enclosures and the effects of shelters (stones, soil) and shade (with and without shade netting) on the activity, exposed body percentage, burrow depth, body-soil contact percentage, and survival of Rana dybowskii were investigated during post-reproductive dormancy and post-dormant activity. The results showed that R. dybowskii live individually under leaves, soil, stones or tree roots. Furthermore, although the dormant sites of frogs are significantly different, the distribution of male and female frogs in these sites is similar. Shading and shelter significantly affected the exposed body percentage, burrow depth and body-soil contact percentage of frogs compared with soil. In the stone group, soil and stone form the frog's refuge/burrow, whereas in the soil group, the refuge/burrow is composed entirely of soil. Even though the soil group has a deeper burrow and a larger area of soil contact with the body, it still has a higher exposure rate than the stone group. Frog activity frequency was affected by shelter and shade; the interaction of shelter and time and the interaction of shading and time were significant. The soil group had a higher activity frequency than the stone group, and the no-shade group had a higher activity frequency than the shade group. Shelter and shading differences do not significantly affect frog survival; however, the death rate during post-reproductive dormancy is lower than that during the active period.

11.
Risk Anal ; 43(5): 875-883, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35648882

RESUMO

This paper relates evidence from the COVID-19 pandemic to the concept of pandemic refuges, as developed in literature on global catastrophic risk. In this literature, a refuge is a place or facility designed to keep a portion of the population alive during extreme global catastrophes. COVID-19 is not the most extreme pandemic scenario, but it is nonetheless a very severe global event, and it therefore provides an important source of evidence. Through the first 2 years of the COVID-19 pandemic, several political jurisdictions have achieved low spread of COVID-19 via isolation from the rest of the world and can therefore classify as pandemic refuges. Their suppression and elimination of COVID-19 demonstrates the viability of pandemic refuges as a risk management measure. Whereas prior research emphasizes island nations as pandemic refuges, this paper uses case studies of China and Western Australia to show that other types of jurisdictions can also successfully function as pandemic refuges. The paper also refines the concept of pandemic refuges and discusses implications for future pandemics.


Assuntos
COVID-19 , Humanos , Pandemias , China/epidemiologia
12.
Sci Total Environ ; 862: 160753, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36513231

RESUMO

Urban infrastructures can provide 'novel' habitats for marine and terrestrial animals and plants, enhancing their ability to adapt to urban environments. In particular, coastal infrastructures characterized by a complex three-dimensional morphology, such as breakwaters, could provide species refuges and food. We investigated the role of breakwaters in providing habitat for vertebrates and plants, and the influence of anthropogenic litter in regulating the value of these structures as habitat. We sampled vertebrate and plant species and quantified the amount of anthropogenic litter on breakwaters and adjacent rocky habitats at several sites in three different countries (Italy, Spain and Chile). We found breakwaters to accumulate more litter items (e.g. especially plastics) than adjacent rocky habitats by means of their large-scale (i.e., 1 m) structural complexity. Birds, which used the artificial infrastructure as transitory habitat, reached similar abundances in breakwaters compared with adjacent rocky platforms. In contrast, synanthropic mammal species, such as Rattus norvegicus and feral cats, were slightly more frequent on breakwaters and appeared to use them as permanent habitat. Plants were frequent in the upper zone of breakwaters and, even though many macrophyte species can trap litter, their cover correlated negatively with anthropogenic litter density. Therefore, breakwaters provide either transitory or permanent habitats for different species, despite functioning as a sink for anthropogenic litter. Thus, new infrastructure should be designed with lower structural complexity in their supralittoral zone limiting the proliferation of synanthropic species. In addition, restricting public access to sensitive areas and enforcing littering fines could enhance the ecological value of these novel habitats by reducing the benefits to pest species.


Assuntos
Ecossistema , Vertebrados , Animais , Gatos , Ratos , Plásticos , Chile , Itália , Monitoramento Ambiental , Mamíferos
13.
Risk Anal ; 43(9): 1824-1842, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36464495

RESUMO

Some island nations in the Southern Hemisphere might survive a severe sun-reducing catastrophe such as nuclear winter and be well placed to help reboot-collapsed human civilization. Such islands must be resilient to the cascading effects abrupt sunlight reduction scenarios (ASRS) would impose beyond the impacts on agricultural systems. We aimed to identify island nations whose societies are most likely to survive nuclear winter or other ASRS. We also aimed to conduct a case study of one island nation to consider how it might enhance its resilience and therefore its chance of aiding a global reboot of complex technological society. We performed a threshold analysis on food self-sufficiency under severe nuclear winter conditions to identify islands. We then profiled each island across global macroindices representing resilience factors reported in the literature. We undertook a case study of the island nation of New Zealand. The island nations of Australia, New Zealand, Iceland, the Solomon Islands, and Vanuatu appear most resilient to ASRS. However, our case-study island nation of New Zealand is threatened in scenarios of no/low trade, has precarious aspects of its energy supply, and shortcomings in manufacturing of essential components. Therefore, inadequate preparations and critical failures in these systems could see rapid societal breakdown. Despite some islands' favorable baseline conditions and apparent food security even in a severe ASRS, cascading impacts through other socioecological systems threaten complex functioning. We identified specific resilience measures, many with cobenefits, which may protect island nodes of sustained complexity in ASRS.


Assuntos
Luz Solar , Humanos , Nova Zelândia , Estações do Ano , Austrália , Islândia
14.
Ecol Evol ; 12(10): e9304, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36225837

RESUMO

The origin of Dahomey Gap (DG) flora is one of the central biogeographical questions in sub-Saharan, which has been addressed in several studies. However, floristic evidence based on representative samples from the DG seems to be lacking in the scientific debate. The present study was conducted to fill this gap. Specifically, we assessed Togolese mountain riparian forests as minor forest refugia, examined their contribution to larger sub-Saharan forest refugia, and discussed the significance of these findings for biogeography and biodiversity conservation. Southwest Togo, West Africa, and sub-Saharan Upper Guinea Region Floristic data were collected in riparian forests through an intensive botanical inventory (n = 198; 50 × 10 m2). A comparative analysis was performed based on the floristic evidence related to forest refuges. The results showed significantly high species richness (868 species) and a high gamma and beta diversity associated with spatial turnover patterns. They also showed a high affinity between the study forests and large sub-Saharan forest refugia. Riparian forests share about 60% of their current species richness with large sub-Saharan forest refugia and contained refuge bio-indicator species. The floristic evidence, consistent with those of other studies, suggests that Togolese mountains would have very ancient origins and have experienced paleoclimatic events. The studied riparian would have served as refuges during recurrent climatic episodes. Our results support the minimal forest fragmentation hypothesis (network of refugia along rivers). However, they seem to be incompatible with the idea that the DG flora may be essentially a relic of the early Holocene. In sub-Saharan Africa, where maintaining a vast area of natural forest is difficult due to human pressure, efforts to preserve maximum species diversity should include a focus on the conservation of minor forest refuges, particularly in sub-humid mountain riparian zone.

15.
Mol Ecol ; 31(20): 5339-5355, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35976256

RESUMO

As high temperature stress due to climate change threatens tropical corals, cooler areas at relatively high latitudes may be potential refuges. Tolerance to low temperatures is critical in determining whether corals can successfully migrate to higher latitudes. However, the physiological and molecular adaptations that protect corals from low temperature stress are unclear. In this study, scleractinian Porites lutea samples from the tropical Xisha Islands (XS) and subtropical Daya Bay (DY) in the South China Sea were subjected to a reduction in ambient temperature from 26 to 12°C. Differences in physiological changes and gene expression were analysed. P. lutea from both XS and DY exhibited physiological bleaching under low temperature stress, and the Symbiodiniaceae density, Fv/Fm, and chlorophyll-α content were significantly reduced. Symbiosome antioxidative stress and metabolic enzyme activity first increased and then decreased. RNA-seq analysis showed that the host responded to low temperature stress by activating immune, apoptotic, and autophagic pathways and reducing metabolic levels. Nevertheless, Symbiodiniaceae lacked the physiological regulatory capacity to adapt to low temperatures. The lower cold tolerance of XS tropical P. lutea may attribute to lower oxidative stress resistance, lower photosynthetic capacity, worse energy supply, and higher susceptibility to bacterial and viral infections and diseases in XS corals. The difference in cold tolerance may result from genetic differences between the geographic populations and is possibly detrimental to the migration of tropical coral to relatively high latitude refuges. This study provides a theoretical basis for anthropogenically assisted coral migration as a response to global change.


Assuntos
Antozoários , Dinoflagellida , Animais , Antozoários/fisiologia , Clorofila , Temperatura Baixa , Recifes de Corais
16.
J Environ Manage ; 318: 115590, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35949080

RESUMO

Due to the global magnitude of forest degradation and deforestation and the high cost of ecological restoration, several approaches have been used to prioritize conservation or restoration areas based on different objectives and criteria. The present work aims to develop a multicriteria approach to defining forest restoration priority areas in the Itacaiúnas River basin, eastern Amazon, that maximizes the criteria equitably. The selected criteria were: improve forest connectivity, provide climatic refuges for biodiversity, mitigate the impacts of deforestation on streamflow, and improve the probability of natural regeneration. A strong difference between selected areas was observed when the criteria of forest connectivity and mitigate the impact on streamflow were considered separately, but greater equity among the criteria was achieved using the multicriteria approach. The most priority areas were concentrated near protected areas. The method used provides a flexible framework, and different criteria or subarea selections can be applied for different purposes to facilitate adaptive management. Analyzing forest restoration prioritization on rural properties can provide guidance for conserving and restoring biodiversity at the landscape scale while complying with legal requirements.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Conservação dos Recursos Naturais/métodos , Florestas , Rios
17.
Animals (Basel) ; 12(11)2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35681894

RESUMO

The current distribution of populations in Europe is marked by the effects of glaciations that occurred during the Pleistocene. Temperate species were isolated in glacial refugia that were the sources of postglacial recolonization. The traditional glacial refuge areas were the Iberian, the Italian and the Balkan peninsulas. Here we revisit the evolutionary history of chamois (Rupicapra genus) to evaluate other sites in continental Europe and Anatolia that have been suggested as potential refuges. We have obtained the complete mitochondrial sequence of seven chamois, including the subspecies parva, carpatica, caucasica, and asiatica whose mitochondrial genome had not been yet reported. These, together with the other fourteen sequences already in the GenBank, represent the different geographical populations of the Rupicapra genus. The phylogenetic analysis showed the three old clades, dating from the early Pleistocene, already reported: mtW in the Iberian Peninsula, mtC in the Appenines and the Massif of Chartreuse, and mtE comprising all the population from the Alps to the east. The genomes within each of the clades mtW and mtE, showed divergence times larger than 300 thousand years. From here, it can be argued that the present-day lineages across Europe are very old and their split dates back to the middle Pleistocene.

18.
Ecol Evol ; 11(21): 14697-14714, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34765135

RESUMO

Understanding factors influencing patterns of genetic diversity and the population genetic structure of species is of particular importance in the current era of global climate change and habitat loss. These factors include the evolutionary history of a species as well as heterogeneity in the environment it occupies, which in turn can change across time. Most studies investigating spatio-temporal genetic patterns have focused on patterns across wide geographic areas rather than local variation, but the latter can nevertheless be important particularly in topographically complex areas. Here, we consider these issues in the Sooty Copper butterfly (Lycaena tityrus) from the European Alps, using genome-wide SNPs identified through RADseq. We found strong genetic differentiation within the Alps with four genetic clusters, indicating western, central, and eastern refuges, and a strong reduction of genetic diversity from west to east. This reduction in diversity may suggest that the southwestern refuge was the largest one in comparison to other refuges. Also, the high genetic diversity in the west may result from (a) admixture of different western refuges, (b) more recent demographic changes, or (c) introgression of lowland L. tityrus populations. At small spatial scales, populations were structured by several landscape features and especially by high mountain ridges and large river valleys. We detected 36 outlier loci likely under altitudinal selection, including several loci related to membranes and cellular processes. We suggest that efforts to preserve alpine L. tityrus should focus on the genetically diverse populations in the western Alps, and that the dolomite populations should be treated as genetically distinct management units, since they appear to be currently more threatened than others. This study demonstrates the usefulness of SNP-based approaches for understanding patterns of genetic diversity, gene flow, and selection in a region that is expected to be particularly vulnerable to climate change.

19.
Curr Biol ; 31(23): 5393-5399.e3, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34739821

RESUMO

The frequency, intensity, and spatial scale of climate extremes are changing rapidly due to anthropogenic global warming.1,2 A growing research challenge is to understand how multiple climate-driven disturbances interact with each other over multi-decadal time frames, generating combined effects that cannot be predicted from single events alone.3-5 Here we examine the emergent dynamics of five coral bleaching events along the 2,300 km length of the Great Barrier Reef that affected >98% of the Reef between 1998 and 2020. We show that the bleaching responses of corals to a given level of heat exposure differed in each event and were strongly influenced by contingency and the spatial overlap and strength of interactions between events. Naive regions that escaped bleaching for a decade or longer were the most susceptible to bouts of heat exposure. Conversely, when pairs of successive bleaching episodes were close together (1-3 years apart), the thermal threshold for severe bleaching increased because the earlier event hardened regions of the Great Barrier Reef to further impacts. In the near future, the biological responses to recurrent bleaching events may become stronger as the cumulative geographic footprint expands further, potentially impairing the stock-recruitment relationships among lightly and severely bleached reefs with diverse recent histories. Understanding the emergent properties and collective dynamics of recurrent disturbances will be critical for predicting spatial refuges and cumulative ecological responses, and for managing the longer-term impacts of anthropogenic climate change on ecosystems.


Assuntos
Antozoários , Animais , Antozoários/fisiologia , Mudança Climática , Recifes de Corais , Ecossistema , Aquecimento Global
20.
J Environ Manage ; 300: 113785, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34562818

RESUMO

Palms are iconic plants. Oil palms are very important economically and originate in Africa where they can act as a model for palms in general. The effect of future climate on the growth of oil palm will be very detrimental. Latitudinal migration of tropical crops to climate refuges may be impossible, and longitudinal migration has only been confirmed for oil palm, of all the tropical crops. The previous method to determine the longitudinal trend for oil palm used the longitudes of various countries in Africa and plotted these against the percentage suitable climate for growing oil palms in each country. An increasing longitudinal trend was observed from west to east. However, the longitudes of the countries were randomly distributed which may have introduced bias and the procedure was time consuming. The present report presents an optimised and systematic procedure that divided the regions, as presented on a map derived from a CLIMEX model, into ten equal sectors and the percentage suitable climates for growing oil palm were determined for each sector. This approach was quicker, systematic and straight forward and will be useful for management of oil palm plantations under climate change. The method confirmed and validated the trends reported in the original method although the suitability values were often lower and there was less spread of values around the trend. The values for the CSIRO MK3.0 and MIROC H models demonstrated considerable similarities to each other, contributing to validation of the method. The procedure of dividing maps equally into sectors derived from models, could be used for other crops, regions, or systems more generally, where the alternative may be a more superficial visual examination of the maps. Methods are required to mitigate the effects of climate change and stakeholders need to contribute more actively to the current climate debate with tangible actions.


Assuntos
Arecaceae , África , Mudança Climática , Produtos Agrícolas , Previsões , Óleo de Palmeira
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