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1.
Sci Rep ; 14(1): 20688, 2024 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237565

RESUMO

Climate change is causing ocean warming (OW) and increasing the frequency, intensity, and duration of extreme weather events, including Marine Heat Waves (MHWs). Both OW and MHWs pose a significant threat to marine ecosystems and marine organisms, including oysters, oyster reefs and farmed oysters. We investigated the survival and growth of juveniles of two commercial species of oyster, the Sydney rock oyster, Saccostrea glomerata, and the Pacific oyster, Crassostrea gigas, to elevated seawater temperatures reflecting a moderate and an extreme MHW in context with recent MHWs and beyond. The survival and size of Pacific oysters to moderate MHWs (22-32 °C; 14 days) was greater than that for Sydney rock oysters (24-32 °C; 15 days). While survival and growth of both species was significantly impacted by extreme MHWs (29-38 °C; 5-6 days), Sydney rock oysters were found to survive greater temperatures compared to the Pacific oyster. Overall, this study found that Pacific oyster juveniles were more tolerant of a moderate MHW, while Sydney rock oyster juveniles were more resilient to extreme MHWs. These differences in thermal tolerance may have consequences for aquaculture and coexistence of both species in their intertidal and latitudinal distributions along the south-eastern Australian coastline.


Assuntos
Mudança Climática , Ostreidae , Animais , Ostreidae/crescimento & desenvolvimento , Ostreidae/fisiologia , Ecossistema , Oceanos e Mares , Temperatura Alta , Espécies Introduzidas , Água do Mar , Crassostrea/crescimento & desenvolvimento , Crassostrea/fisiologia
2.
Nutrients ; 16(17)2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39275133

RESUMO

Global warming poses a significant threat to our planet, with the food sector contributing up to 37% of total greenhouse gas emissions. This study aimed to assess the climate change impact and healthiness of menus in a long-term care facility in Italy. We analyzed two 28-day cyclical menus using the carbon footprint (CF) and the Modified EAT-Lancet Diet Score (MELDS) to evaluate adherence to the Planetary Health Diet (PHD). Monte Carlo simulations were employed to explore 20,000 daily menu permutations. Results showed that the mean GHGEs of spring/summer and autumn/winter daily menus were 2.64 and 2.82 kg of CO2eq, respectively, with 99% of menus exceeding the 2.03 kg of CO2eq benchmark. Only 22% of menus were adherent to the PHD, with MELDSs ranging from 12 to 29. A strong inverse association between the CF and adherence to the PHD was observed. These findings suggest significant potential for reducing the CFs of meals served in nursing homes while promoting adherence to a planetary diet, presenting an opportunity to set new standards in caregiving and environmental sustainability.


Assuntos
Pegada de Carbono , Assistência de Longa Duração , Casas de Saúde , Valor Nutritivo , Itália , Humanos , Pegada de Carbono/estatística & dados numéricos , Mudança Climática , Dieta Saudável/estatística & dados numéricos , Estações do Ano , Método de Monte Carlo , Serviços de Alimentação/normas
3.
BMC Pregnancy Childbirth ; 24(1): 344, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704541

RESUMO

BACKGROUND: Climate change, particularly global warming, is amongst the greatest threats to human health. While short-term effects of heat exposure in pregnancy, such as preterm birth, are well documented, long-term effects have received less attention. This review aims to systematically assess evidence on the long-term impacts on the foetus of heat exposure in utero. METHODS: A search was conducted in August 2019 and updated in April 2023 in MEDLINE(PubMed). We included studies on the relationship of environmental heat exposure during pregnancy and any long-term outcomes. Risk of bias was assessed using tools developed by the Joanna-Briggs Institute, and the evidence was appraised using the GRADE approach. Synthesis without Meta-Analysis (SWiM) guidelines were used. RESULTS: Eighteen thousand six hundred twenty one records were screened, with 29 studies included across six outcome groups. Studies were mostly conducted in high-income countries (n = 16/25), in cooler climates. All studies were observational, with 17 cohort, 5 case-control and 8 cross-sectional studies. The timeline of the data is from 1913 to 2019, and individuals ranged in age from neonates to adults, and the elderly. Increasing heat exposure during pregnancy was associated with decreased earnings and lower educational attainment (n = 4/6), as well as worsened cardiovascular (n = 3/6), respiratory (n = 3/3), psychiatric (n = 7/12) and anthropometric (n = 2/2) outcomes, possibly culminating in increased overall mortality (n = 2/3). The effect on female infants was greater than on males in 8 of 9 studies differentiating by sex. The quality of evidence was low in respiratory and longevity outcome groups to very low in all others. CONCLUSIONS: Increasing heat exposure was associated with a multitude of detrimental outcomes across diverse body systems. The biological pathways involved are yet to be elucidated, but could include epigenetic and developmental perturbations, through interactions with the placenta and inflammation. This highlights the need for further research into the long-term effects of heat exposure, biological pathways, and possible adaptation strategies in studies, particularly in neglected regions. Heat exposure in-utero has the potential to compound existing health and social inequalities. Poor study design of the included studies constrains the conclusions of this review, with heterogenous exposure measures and outcomes rendering comparisons across contexts/studies difficult. TRIAL REGISTRATION: PROSPERO CRD 42019140136.


Assuntos
Temperatura Alta , Efeitos Tardios da Exposição Pré-Natal , Humanos , Feminino , Gravidez , Temperatura Alta/efeitos adversos , Mudança Climática , Recém-Nascido , Adulto
4.
PLoS One ; 18(9): e0290643, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37729181

RESUMO

Climate change and climate variability are affecting marine mammal species and these impacts are projected to continue in the coming decades. Vulnerability assessments provide a framework for evaluating climate impacts over a broad range of species using currently available information. We conducted a trait-based climate vulnerability assessment using expert elicitation for 108 marine mammal stocks and stock groups in the western North Atlantic, Gulf of Mexico, and Caribbean Sea. Our approach combined the exposure (projected change in environmental conditions) and sensitivity (ability to tolerate and adapt to changing conditions) of marine mammal stocks to estimate vulnerability to climate change, and categorize stocks with a vulnerability index. The climate vulnerability score was very high for 44% (n = 47) of these stocks, high for 29% (n = 31), moderate for 20% (n = 22), and low for 7% (n = 8). The majority of stocks (n = 78; 72%) scored very high exposure, whereas 24% (n = 26) scored high, and 4% (n = 4) scored moderate. The sensitivity score was very high for 33% (n = 36) of these stocks, high for 18% (n = 19), moderate for 34% (n = 37), and low for 15% (n = 16). Vulnerability results were summarized for stocks in five taxonomic groups: pinnipeds (n = 4; 25% high, 75% moderate), mysticetes (n = 7; 29% very high, 57% high, 14% moderate), ziphiids (n = 8; 13% very high, 50% high, 38% moderate), delphinids (n = 84; 52% very high, 23% high, 15% moderate, 10% low), and other odontocetes (n = 5; 60% high, 40% moderate). Factors including temperature, ocean pH, and dissolved oxygen were the primary drivers of high climate exposure, with effects mediated through prey and habitat parameters. We quantified sources of uncertainty by bootstrapping vulnerability scores, conducting leave-one-out analyses of individual attributes and individual scorers, and through scoring data quality for each attribute. These results provide information for researchers, managers, and the public on marine mammal responses to climate change to enhance the development of more effective marine mammal management, restoration, and conservation activities that address current and future environmental variation and biological responses due to climate change.


Assuntos
Caniformia , Mudança Climática , Animais , Golfo do México , Região do Caribe , Mamíferos , Cetáceos
5.
Sci Bull (Beijing) ; 68(4): 424-435, 2023 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-36732118

RESUMO

Synergistically maintain or enhance the numerous beneficial contributions of nature to the quality of human life is an important but challenging question for achieving Sustainable Development Goals. However, the spatiotemporal distributions of global nature's contributions to people (NCPs) and their interactions remain unclear. We built a rapid assessment indicator framework and produced the first spatially explicit assessment of all 18 NCPs at a global scale. The 18 global NCPs in 1992 and 2018 were globally assessed in 15,204 subbasins based on two spatial indicator dimensions, including nature's potential contribution and the actual contribution to people. The results show that most of the high NCP values are highly localized. From 1992 to 2018, 6 regulating NCPs, 3 material NCPs, and 2 nonmaterial NCPs declined; 29 regulating-material NCP combinations (54 in total) dominated 76% of the terrestrial area, and the area with few NCPs accounted for 22%; and synergistic relationships were more common than tradeoff relationships, while the relationships among regulating and material NCPs generally traded-off with each other. Transitional climate areas contained few NCPs and have strong tradeoff relationships. However, the high synergistic relationship among NCPs in low latitudes could be threatened by future climate change. These findings provide a general spatiotemporal understanding of global NCP distributions and can be used to interpret the biogeographic information in a functional way to support regional coordination and achieve landscape multifunctionality for the enhancement of human well-being.


Assuntos
Mudança Climática , Desenvolvimento Sustentável , Humanos
6.
Conserv Biol ; 37(1): e14045, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36511895

RESUMO

Species shift their distribution in response to climate and land-cover change, which may result in a spatial mismatch between currently protected areas (PAs) and priority conservation areas (PCAs). We examined the effects of climate and land-cover change on potential range of gibbons and sought to identify PCAs that would conserve them effectively. We collected global gibbon occurrence points and modeled (ecological niche model) their current and potential 2050s ranges under climate-change and different land-cover-change scenarios. We examined change in range and PA coverage between the current and future ranges of each gibbon species. We applied spatial conservation prioritization to identify the top 30% PCAs for each species. We then determined how much of the PCAs are conserved in each country within the global range of gibbons. On average, 31% (SD 22) of each species' current range was covered in PAs. PA coverage of the current range of 9 species was <30%. Nine species lost on average 46% (SD 29) of their potential range due to climate change. Under climate-change with an optimistic land-cover-change scenario (B1), 12 species lost 39% (SD 28) of their range. In a pessimistic land-cover-change scenario (A2), 15 species lost 36% (SD 28) of their range. Five species lost significantly more range under the A2 scenario than the B1 scenario (p = 0.01, SD 0.01), suggesting that gibbons will benefit from effective management of land cover. PA coverage of future range was <30% for 11 species. On average, 32% (SD 25) of PCAs were covered by PAs. Indonesia contained more species and PCAs and thus has the greatest responsibility for gibbon conservation. Indonesia, India, and Myanmar need to expand their PAs to fulfill their responsibility to gibbon conservation. Our results provide a baseline for global gibbon conservation, particularly for countries lacking gibbon research capacity.


Las especies modifican su distribución como respuesta a los cambios en el clima y el uso de suelo, lo que puede derivar en una disparidad espacial entre las áreas protegidas (AP) y las áreas de conservación prioritarias (ACP). Analizamos los efectos del cambio en el clima y el uso de suelo sobre la distribución potencial de los gibones para identificar las ACP que lograrían su conservación exitosa. Recopilamos puntos globales de presencia de gibones y modelamos (modelo de nicho ecológico) su distribución actual y potencial para la década de 2050 bajo diferentes escenarios de cambio climático y de uso de suelo. Después exploramos los cambios en la distribución y la cobertura de las AP entre la distribución actual y a futuro de cada especie de gibón y aplicamos la priorización de la conservación espacial para identificar el mejor 30% de ACP para cada especie. Posteriormente determinamos la extensión conservada de las ACP en cada país dentro de la distribución mundial de gibones. En promedio, el 31% (DS 22) de la distribución actual de cada especie está cubierta en las AP. La distribución actual de nueve especies tiene una cobertura de áreas protegidas menor al 30%. Como promedio, nueve especies perdieron el 46% (DS 29) de su rango potencial debido al cambio climático. Bajo un escenario de cambio climático con un cambio de suelo optimista (B1), doce especies perdieron el 39% (DS 28) de su distribución. Con un escenario pesimista (A2), 15 especies perdieron el 36% (DS 28) de su distribución. Cinco especies perdieron considerablemente más distribución bajo el escenario A2 en relación con el B1 (p = 0.01, SD 0.01), lo que sugiere que los gibones se beneficiarán con la gestión efectiva de la cobertura terrestre. La cobertura dentro de las AP de la distribución futura fue < 30% para once especies. En promedio, el 32% (DS 25) de las ACP estuvo cubierto dentro de las AP. Indonesia albergó más especies y más ACP, por lo que tuvo la mayor responsabilidad en la conservación de los gibones. Indonesia, India y Myanmar necesitan expandir sus AP para cumplir con su responsabilidad en la conservación de los gibones. Nuestros resultados proporcionan una línea base para la conservación mundial de los gibones, particularmente para aquellos países que carecen de los recursos para investigarlos.


Assuntos
Biodiversidade , Ecossistema , Animais , Hylobates , Conservação dos Recursos Naturais/métodos , Mudança Climática
7.
Lancet Planet Health ; 6(9): e726-e738, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36087603

RESUMO

BACKGROUND: The COVID-19 pandemic and climate change are both significant and pressing global challenges, posing threats to public health and wellbeing. Young people are particularly vulnerable to the distress both crises can cause, but understanding of the varied psychological responses to both issues is poor. We aimed to investigate these responses and their links with mental health conditions and feelings of agency. METHODS: We conducted an online survey between Aug 5 and Oct 26, 2020, targeting a diverse sample of young people (aged 16-24 years, n=530) in the UK. The survey was distributed using a combination of a survey panel (panel sample) and direct approaches to youth groups and schools who shared the survey with young people in their networks (community sample). We collected data on respondents' psychological responses to both climate change and the COVID-19 pandemic, their sense of agency to respond to each crisis, and the range of impacts on their lives. We also collected demographics data and screened for mental health and wellbeing indicators. We used non-parametric tests for most statistical comparisons. For paired samples, we used Wilcoxon's signed-rank test, and used Mann-Whitney U-tests or Kruskal-Wallis tests for two or more independent samples. Summed scale scores were considered as interval-level data and analysed with Student's t tests and ANOVAs. Effect sizes are reported as Cohen's d and partial eta-squared (η·2p), respectively. FINDINGS: After excluding 18 suspected bots and 94 incomplete responses, 530 responses were retained for analysis. Of the 518 respondents who provided demographic data, 63% were female, 71·4% were White, and the mean family affluence score was 8·22 (SD 2·29). Most participants (n=343; 70%) did not report a history of diagnosis or treatment for a mental health disorder, but mental health scores indicated a common experience of (relatively mild) symptoms of anxiety, depression, and stress. Although UK youth reported more life disruption and concern for their future due to the COVID-19 pandemic, climate change was associated with significantly greater distress overall, particularly for individuals with low levels of generalised anxiety. The COVID-19 pandemic was more associated with feelings of anxiety, isolation, disconnection, and frustration; distress around loss and grief; and effects on quality of life. Climate change was more likely to evoke emotions such as interest and engagement, guilt, shame, anger, and disgust. The greater distress attributed to climate change overall was due, in particular, to higher levels of guilt, sense of personal responsibility, and greater distress triggered by upsetting media coverage. Agency to address climate change was associated with greater climate distress, but pandemic-related distress and agency were unrelated. INTERPRETATION: The COVID-19 pandemic and climate change are affecting the wellbeing of UK young people in distinct ways, with implications for health service, policy, and research responses. There is a need for mental health practitioners, policy makers, and other societal actors to account for the complex relationship between climate agency, distress, and mental wellbeing in young people. FUNDING: Imperial College London.


Assuntos
COVID-19 , Saúde Mental , Adolescente , COVID-19/epidemiologia , COVID-19/psicologia , Mudança Climática , Feminino , Humanos , Masculino , Pandemias , Qualidade de Vida , Inquéritos e Questionários , Reino Unido/epidemiologia , Adulto Jovem
8.
Environ Monit Assess ; 194(9): 596, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35861887

RESUMO

Reliable predictions of future distribution ranges of ecologically important species in response to climate change are required for developing effective management strategies. Here we used an ensemble modelling approach to predict the distribution of three important species of Abies namely, Abies pindrow, Abies spectabilis and Abies densa in the Hindu Kush Himalayan region under the current and two shared socioeconomic pathways (SSP245 and SSP585) and time periods of 2050 and 2090s. A correlative ensemble model using presence/absence data of the three Abies species and 22 environmental variables, including 19 bioclimatic variables and 3 topographic variables, from known distributions was built to predict the potential current and future distribution of these species. The individual models used to build the final ensemble performed well and provided reliable results for both the current and future distribution of all three species. For A. pindrow, precipitation of the driest month (Bio14) was the most important environmental variable with 83.3% contribution to model output while temperature seasonality (Bio4) and annual mean diurnal range (Bio2) were the most important variables for A. spectabilis and A. densa with 48.4% and 46.1% contribution to final model output, respectively. Under current climatic conditions, the ensemble models projected a total suitable habitat of about 433,003 km2, 790,837 km2 and 676,918 km2 for A. pindrow, A. spectabilis and A. densa, respectively, which is approximately 10.36%, 18.91% and 16.91% of the total area of Hindu Kush Himalayan region. Projections of habitat suitability under future climate scenarios for all the shared socioeconomic pathways showed a reduction in potentially suitable habitats with a maximum overall loss of approximately 14% of the total suitable area of A. pindrow under SSP 8.5 by 2090. A decline in total suitable habitat is predicted to be 9.6% in A. spectabilis by 2090 under the SSP585 scenario while in A. densa 6.67% loss in the suitable area is expected by 2050 under the SSP585 scenario. Furthermore, there is no elevational change predicted in the case of A. pindrow while A. spectabilis is expected to show an upward shift by about 29 m per decade and A. densa is showing a downward shift at a rate of 11 m per decade. The results are interesting, and intriguing given the occurrence of these species across the Hindu Kush Himalayan region. Thus, our study underscores the need for consideration of unexpected responses of species to climate change and formulation of strategies for better forest management and conservation of important conifer species, such as A. pindrow, A. spectabilis and A. densa.


Assuntos
Abies , Mudança Climática , Ecossistema , Monitoramento Ambiental , Florestas
9.
Glob Chang Biol ; 28(10): 3275-3292, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35199413

RESUMO

The boreal forest biome is a major component of Earth's biosphere and climate system that is projected to shift northward due to continued climate change over the coming century. Indicators of a biome shift will likely first be evident along the climatic margins of the boreal forest and include changes in vegetation productivity, mortality, and recruitment, as well as overall vegetation greenness. However, the extent to which a biome shift is already underway remains unclear because of the local nature of most field studies, sparsity of systematic ground-based ecological monitoring, and reliance on coarse resolution satellite observations. Here, we evaluated early indicators of a boreal forest biome shift using four decades of moderate resolution (30 m) satellite observations and biogeoclimatic spatial datasets. Specifically, we quantified interannual trends in annual maximum vegetation greenness using an ensemble of vegetation indices derived from Landsat observations at 100,000 sample sites in areas without signs of recent disturbance. We found vegetation greenness increased (greened) at 38 [29, 42] % and 22 [15, 26] % of sample sites from 1985 to 2019 and 2000 to 2019, whereas vegetation greenness decreased (browned) at 13 [9, 15] % and 15 [13, 19] % of sample sites during these respective periods [95% Monte Carlo confidence intervals]. Greening was thus 3.0 [2.6, 3.5] and 1.5 [0.8, 2.0] times more common than browning and primarily occurred in cold sparsely treed areas with high soil nitrogen and moderate summer warming. Conversely, browning primarily occurred in the climatically warmest margins of both the boreal forest biome and major forest types (e.g., evergreen conifer forests), especially in densely treed areas where summers became warmer and drier. These macroecological trends reflect underlying shifts in vegetation productivity, mortality, and recruitment that are consistent with early stages of a boreal biome shift.


Assuntos
Ecossistema , Taiga , Mudança Climática , Florestas , Árvores
10.
Sci Total Environ ; 806(Pt 2): 150600, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34592296

RESUMO

Fish production from aquaculture and wild captures suffers from the rising risk of climate change. This impacts the livelihoods of fishers and fish farmers by shrinking wild fishery stocks, inland water scarcity, and consequent declines in economic and protein productions. China, feeding the most fish of the world with water-intensive crops, faces challenges of water scarcity but still be premature in developing strategies to adapt to climate change. Here, focusing on methodology development, we quantified the water footprint of fish-farming and economic and protein productions in the baseline year 2014. Then, 29 scenarios of farmed-fish-species composition (FFSC, i.e., tons of each farmed fish species) were developed for the target year 2020. The baseline 2014 shows that fish farming generates an average of 150 billion m3 of water footprint, 4.70 million tons of protein, and 263 billion RMB of economic output (~39 billion USD). Uncertainty optimizations were conducted to generate the optimal FFSC solutions that show a potential to increase fish production by 22%, economic and protein output by 18% and 29%, respectively and simultaneously lower water footprint by 22% to the maximum extent. Nine scenarios that lower wild fishery captures were further examined, with optimal FFSC solution that encourages aquaculture of Grass carp, Bighead Carp, and Silver Carp, and discourages Black carp, Tilapia, Crucian carp, Sea bass, and Wuchang bream. From a methodology aspect, this study pulls back policymakers from only focusing on the short-term economic interest of fish-farming and persuades them to rethink long-term adaptive strategies to climate change from multiple sustainable dimensions.


Assuntos
Conservação dos Recursos Hídricos , Cyprinidae , Animais , Aquicultura , Mudança Climática , Pesqueiros
11.
Environ Sci Pollut Res Int ; 29(1): 509-517, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34333747

RESUMO

In order to explore the characteristics of climate change in the future in the West Liao River Basin under the background of future climate change, this study analyzed the changes of the annual average temperature, annual precipitation, and annual evapotranspiration from 2021 to 2060 in the West Liao River Basin under the scenarios of RCP4.5 (low emission) and RCP8.5 (high emission) originated from Intergovernmental Panel on Climate Change's Fifth Assessment Report. The results show that (1) under the two different scenarios (RCP4.5 and RCP8.5), the annual average temperature in the West Liao River Basin is 7.67 °C and 8.12 °C, respectively, and the temperature shows an upward trend; the mutation years of RCP4.5 are more than those of RCP8.5; the annual average temperature of RCP4.5 is controlled by periods of 22 years and 29 years, while RCP8.5 has only one main period of 29 years; the contribution rates of the first eigenvector variance of EOF are 97.12% and 96.64%, respectively, and the change types are the same. The sensitive areas of variation are in the southwest and western regions respectively. (2) The annual precipitation in the West Liao River Basin under the two scenarios are 815.78mm and 798.64mm, with tendency rates of -20.51/mm/10a and 17.26/mm/10a; the mutation years in the West Liao River Basin under scenario RCP4.5 are mostly occurred in the 2030s and 2040s, while those under scenario RCP8.5 are mostly occurred in 2040s and 2050s; under scenario RCP4.5, the change is mainly controlled by shorter periods, while under scenario RCP8.5, the change is controlled by two main longer periods of 19 years and 28 years. Under the two scenarios of RCP4.5 and RCP8.5, the cumulative contribution rates of the variance of the first three eigenvectors of the EOF in the West Liao River Basin are 42% and 90.23% respectively. The first eigenvector is consistent, and the second and third eigenvectors are the reverse type of South (East)-North (West). (3) The results show that the annual evapotranspiration in the West Liao River Basin under the scenarios of RCP4.5 and RCP8.5 is 597.79mm and 618.45mm, respectively, and the trend rates are 18.20/mm/10a and 4.48/mm/10a; under scenario RCP4.5, the change is controlled by periods of 23 years and 29 years, while under scenarios RCP8.5, the change is controlled by periods of 18 years and 28 years; the contribution rates of the first eigenvector variance of EOF are 91.05% and 89.51% respectively, and they are consistent distribution, and their sensitive areas are in the southeast and central regions respectively.


Assuntos
Mudança Climática , Rios , Previsões , Temperatura
12.
PLoS One ; 16(9): e0256146, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34499686

RESUMO

Sharks and rays are at risk of extinction globally. This reflects low resilience to increasing fishing pressure, exacerbated by habitat loss, climate change, increasing value in a trade and inadequate information leading to limited conservation actions. Artisanal fisheries in the Bay of Bengal of Bangladesh contribute to the high levels of global fishing pressure on elasmobranchs. However, it is one of the most data-poor regions of the world, and the diversity, occurrence and conservation needs of elasmobranchs in this region have not been adequately assessed. This study evaluated elasmobranch diversity, species composition, catch and trade within the artisanal fisheries to address this critical knowledge gap. Findings show that elasmobranch diversity in Bangladesh has previously been underestimated. In this study, over 160000 individual elasmobranchs were recorded through landing site monitoring, comprising 88 species (30 sharks and 58 rays) within 20 families and 35 genera. Of these, 54 are globally threatened according to the IUCN Red List of Threatened Species, with ten species listed as Critically Endangered and 22 species listed as Endangered. Almost 98% juvenile catch (69-99% for different species) for large species sand a decline in numbers of large individuals were documented, indicating unsustainable fisheries. Several previously common species were rarely landed, indicating potential population declines. The catch pattern showed seasonality and, in some cases, gear specificity. Overall, Bangladesh was found to be a significant contributor to shark and ray catches and trade in the Bay of Bengal region. Effective monitoring was not observed at the landing sites or processing centres, despite 29 species of elasmobranchs being protected by law, many of which were frequently landed. On this basis, a series of recommendations were provided for improving the conservation status of the elasmobranchs in this region. These include the need for improved taxonomic research, enhanced monitoring of elasmobranch stocks, and the highest protection level for threatened taxa. Alongside political will, enhancing national capacity to manage and rebuild elasmobranch stocks, coordinated regional management measures are essential.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Espécies em Perigo de Extinção/estatística & dados numéricos , Pesqueiros/estatística & dados numéricos , Tubarões/fisiologia , Rajidae/fisiologia , Animais , Bangladesh , Mudança Climática , Oceanos e Mares , Dinâmica Populacional , Tubarões/classificação , Rajidae/classificação
13.
PLoS One ; 16(5): e0252133, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34029349

RESUMO

Sufficient samples of extreme precipitation events are needed in order to obtain reliable estimates of the probability of their occurrence. Here, we use a large ensemble simulation with 50 members from the Canadian Earth System Model (CanESM2) under the representative concentration pathway 8.5 (RCP8.5) scenario to give future projection of the intensity and frequency of extreme precipitation events under different warming levels relative to the current climate over China. A bias-correction method based on quantile mapping is first used to remove systematic biases in the ensemble. The return value and return period are obtained by fitting enough annual maximum precipitation samples with the generalized extreme value to represent the intensity and frequency of extreme events, respectively. The results show that the average intensity of extreme precipitation in China will increase by nearly 8% per 1°C of global warming, which closely follows the Clausius-Clapeyron relation. Rarer extreme events will experience greater changes in frequency, especially under higher warming. The nationally averaged extreme precipitation events, presently expected to occur every 50 years (100 years) under the current climate conditions, are expected to occur approximately every 41 years (82 years), 32 years (62 years), 22 years (42 years) and 15 years (29 years) under warming levels of 1.5, 2.0, 3.0 and 4.0°C, respectively. Northwestern China (NW), southwestern China (SW) and the Yangtze River valley (YZ) exhibit the greatest increase in probability ratio (PR) under future climate condition. The risk of extreme precipitation events, currently expected to occur once every 50 years, will be nearly 11 (21) times more likely to occur under a climate warming by 3.0°C (4.0°C). Limiting warming to 1.5°C will help avoid approximately 40%-50%, 70%-80% and over 90% of the increase in the risk of extreme events in almost all subregions if the global mean surface temperature (GMST) continues warming to 2.0°C, 3.0°C and 4.0°C, respectively. Our study provides a useful information for the understanding the impact of climate change on the future risk of extreme events over China.


Assuntos
Clima , Canadá , China , Mudança Climática , Temperatura
14.
Multimedia | Recursos Multimídia | ID: multimedia-8785

RESUMO

0:00:34 CL Hello, good day and welcome to... wherever you are listening to us today from [sic]. It's Monday 19th April 2021. My name is Christian Lindmeier and I'm welcoming you to today's global COVID-19 press conference. The press conference today is on COVID updates with a special focus on the linkages between the climate and the COVID-19 crisis and the role of youth in the response ahead of Earth Day, which is 22nd April, and the first Global Youth Summit organised as part of the global youth mobilisation, which is 23rd to 25th April. Today's press conference will include three special guests and I'm happy to welcome Greta Thunberg, Climate and Environmental Activist, Elahi Rawshan from Bangladesh, volunteer in the International Federation of the Red Cross and Red Crescent Society, supporting young people in Bangladesh, and Daisy Moran from the USA, Global Youth Mobilisation Youth Board Member and World YMCA Representative. Welcome to the three of you. We will have simultaneous interpretation as usual provided in the six official UN languages, Arabic, Chinese, French, English, Spanish and Russian, plus Portuguese and Hindi. Now let me introduce the participants here in the room. Present in the room are Dr Tedros Adhanom Ghebreyesus, WHO Director-General, Dr Maria Van Kerkhove, Technical Lead on COVID-19, Dr Bruce Aylward, Special Advisor to the Director-General and the Lead on the ACT Accelerator. We have Mr Anil Suni, Chief Executive Officer from the WHO Foundation and we have Dr Maria Nera, Director for Health and Environment. We also have joining us remotely today Dr Mike Ryan, Executive Director for the Health Emergencies Programme of WHO, and Dr Mariangela Simao, Assistant Director-General for Access to Medicines and Health Products. With this let me hand over to the Director-General for the introductory remarks. Dr Tedros, the floor is yours. Thank you. Thank you, Christian. Good morning, good afternoon and good evening. Last week new cases of COVID-19 increased for the eighth week in a row with more than 5.2 million cases reported, the most in a single week so far. Deaths rose for the fifth straight week and more than three million deaths have now been reported to WHO. It took nine months to reach one million deaths, four months to reach two million and three months to reach three million deaths. Big numbers can make us numb but each one of these deaths is a tragedy for families, communities and nations. Infections and hospitalisations among people aged 25 to 59 are increasing at an alarming rate, possibly as a result of highly transmissible variants and increased social mixing among younger adults. 00:04:28 Today the emergency committee gave me its advice on vaccines, variants, international travel and other issues. Its full statement is available on our website. We have the tools to bring this pandemic under control in a matter of months if we apply them consistently and equitably. On Friday WHO issued an expression of interest for establishing a COVID-19 technology transfer hub for MRNA vaccines to increase production of those vaccines in low and middle-income countries. We're calling for the original manufacturers of MRNA vaccines to contribute their technology and know-how and for manufacturers in low and middle-income countries to express interest in receiving that technology. We have seen incredible innovation in science. Now we need innovation to ensure as many people as possible benefit from that science. The pandemic will recede but we will still be left with all the other challenges that we had before including the climate crisis. 00:05:58 This week marks Earth Day on 22nd April, a reminder that human health depends on the health of the planet that sustains us. COVID-19 has now killed more than three million people. Air pollution kills more than double that number, seven million people every single year. Despite temporary improvements in air quality last year as a result of so-called lock-downs by September air pollution had returned to pre-pandemic levels. Globally CO2 emissions only decreased by less than 6% last year but by December they had rebounded to their previous levels. The health argument for climate action is crystal-clear. The same unsustainable choices that are killing our planet are killing people. There is no vaccine for climate change but we do have solutions. Last year WHO published our manifesto for a healthy and green recovery, calling on all governments to protect nature, support clean energy sources, develop sustainable food systems and healthier cities and reduce polluting activities. 00:07:36 Together the six prescriptions of the WHO manifesto can not only restore resilient economies; they are a linchpin and essential prerequisite for healthy societies. At the COP26 climate conference in Glasgow this year WHO will deliver a special report with recommendations on how to maximise the health benefits of tackling climate change while avoiding the worst health impacts of the climate crisis. WHO is also spearheading an initiative on promoting climate-resistant health systems in collaboration with the Government of the United Kingdom. Today it's my honour to welcome someone who needs no introduction. Over the past few years Greta Thunberg has become the powerful voice of a young generation demanding climate action. Greta's mobilisation of communities, particularly young people, has been truly inspirational and has brought into sharp focus the impact of the climate crisis on people's lives and the urgent need for transformative action. The awareness she has raised on the links between climate, the environment and health has supported WHO's agenda in these areas, demonstrated the threats all of us face and the role young people can play in building a more sustainable, safer, healthier world. 00:09:33 More recently she has become a powerful advocate for vaccine equity. Tack så mycket, Greta. Today Greta has announced a donation of €100,000 from the Greta Thunberg Foundation to the WHO Foundation in support of COVAX to provide vaccines to people in need. Greta, thank you, tack så mycket for your superb advocacy for climate action and now for vaccine equity. Your contribution makes you the youngest person to contribute to COVAX. Welcome and you have the floor. GT Thank you so much for having me. It is an honour to participate in this event and I will talk briefly now. Science shows that in the future we will most likely experience more frequent and more devastating pandemics unless we drastically change our ways and the way we treat nature. Today up to 75% of all emerging diseases come from animals and as we are cutting down forests and destroying habitats we are creating the ideal conditions for diseases to spill over from one animal to another and then to us. 00:11:08 We can no longer separate the health crisis from the ecological crisis and we cannot separate the ecological crisis from the climate crisis. It's all interlinked in many ways. During this pandemic we have seen what we can achieve when we put resources into science. Vaccines were developed in record time but so far on average one in four people in high-income countries have received a coronavirus vaccine compared with just one in over 500 in low and middle-income countries. The international community, governments and vaccine developers must step up their game and address the tragedy that is vaccine inequity. We have the tools we need to correct this great imbalance that exists around the world today in the fight against COVID-19. Just as with the climate crisis those who are the most vulnerable need to be prioritised and global problems require global solutions. It is completely unethical that high-income countries are now vaccinating young and healthy people if that happens at the expense of people in risk groups and on the front lines in low and middle-income countries. This is a moral test. We talk today about showing solidarity and yet vaccine nationalism is what's running the vaccine distribution. It is only when it really comes down to it that we show our true face and that is why I and many others are supporting WHO, GAVI and all involved in the COVAX initiative, which I believe offers the best path forward to ensure a more equitable global vaccine distribution and a way out of this pandemic. Thank you. 00:13:04 TAG Thank you. Thank you so much, Greta, and thank you for your generosity in donating to the WHO Foundation in support of COVAX. These funds will help us save lives. Around the world young people have been affected by the pandemic in many ways from disruptions in education, loss of employment opportunities, mental health challenges and increased domestic and gender-based violence. WHO is committed to ensuring that the global recovery from COVID-19 includes the voices, energy and ideas of young people. To do that we have partnered with an alliance of the six largest youth development organisations in the world to form the Global Youth Mobilisation, to empower young people to respond to the challenges created by the pandemic in their local communities. 00:14:08 The Global Youth Mobilisation has established a grant mechanism with funds from the Solidarity Response Fund to support innovative local solutions to address the impact of the COVID-19 pandemic. From today young people around the world will be able to apply for grants of between 500 and US$5,000 through the Global Youth Mobilisation. These local solutions will be judged and decided on by young people for young people. To mark the starting point for young people to get involved in the Global Youth Mobilisation a Global Youth Summit will be held virtually from this Friday to Sunday, 23rd to 25th April. Over three days thousands of young people, leaders, policymakers and change-makers will come together in one space to discuss the issues facing young people across the world. On behalf of the Big Six youth organisations, the United Nations Foundation and WHO I invite everyone to join us at the Global Youth Summit. Today I'm delighted to be joined by representatives from two of the Big Six organisations. First it's my honour to welcome Elahi Rawshan, a volunteer with the International Federation of the Red Cross and Red Crescent Societies in Bangladesh. Elahi, thank you for joining us today. You have the floor. 00:16:05 ER Thank you, Dr Tedros, for inviting me here today. I'm really honoured to be here. My name is Elahi Rawshan. I'm a Red Cross/Red Crescent youth volunteer living in Bangladesh. There are about three million young people around the world how have been taking action to respond to the COVID-19 pandemic, driving the response efforts and supporting their local communities. I'd like to share with you my story to help explain why recognising, championing and investing in young people through the Global Youth Mobilisation is important. I led the very first disinfection team of Bangladesh Red Crescent Society in different hospitals for two consecutive months. At the beginning of the pandemic here the hospitals needed more supporting hands and we wanted to make sure the hospital environment was safe for everyone and we did to a great extent. One day when the very first COVID patient died in a hospital and everyone was so frightened to go near him, even his own son was reluctant to take his father's body. We went in, we disinfected the room and made sure the body was safe for carrying. 00:17:31 Another day I carried a critical COVID patient on a wheelchair and put an oxygen mask on her when there was no-one around for the support of that person. But I was not the only one; there are thousands of young people in Bangladesh fighting this battle in many different forms. About 4,500 young volunteers of the Red Crescent Society are supporting the vaccination programme every day in Bangladesh. It's mostly the young people here who are making a difference and again it's the young people here who are mostly infected by the pandemic. Many of my friends, colleagues from the different youth organisations and networks have lost their jobs. Almost everyone here is suffering from mental health issues. The data shows that from March 2020 to February 2021 more than 14,000 have committed suicide, which is 45% higher than the previous year and the majority of them are young people. 00:18:44 My dear friends, I have seen localised action making a positive impact on people's lives during this pandemic. I have been trying to collaborate with the Red Crescent Society with my workplace [unclear] who have been offering an online skills programme for the young people. Now as both parties have agreed the Red Crescent youth volunteers will receive a three-month online skills training on different trades like graphics designing, web development, etc. I believe drives like this will help young people individually and at the same time will contribute to the national economy. There are plenty of organisations and individuals out there who are making many more new initiatives to combat this COVID crisis and I would like to invite them all to collaborate with the Global Youth Mobilisation and it will support, promote and invest in your initiatives for improving more lives and communities. Thank you. TAG Thank you. Thank you so much, Elahi. Next it's my pleasure to introduce Daisy Moran, a representative of the World YMCA and a board member of the Global Youth Mobilisation. Daisy, thank you for joining us and you have the floor. 00:20:16 DM Thank you for giving me this opportunity, Dr Tedros, and greetings to you all. I'm Daisy Moran, proud to be with the YMCA in Illinois, USA and proud to be one of the six youth board representatives of the Global Youth Mobilisation. Here's what youth mobilisation has meant for me as the COVID pandemic has significantly increased the inequities in all of our societies. As a young leader I saw a need in my community to offer relief to essential workers who are undocumented immigrants. Through collaboration with fellow young change-makers and organisations we were able to disburse almost $17,000 in relief funds for 38 families. This is just one of thousands of stories that illustrate the simple and powerful fact; when given access and opportunities young people can make a significant difference. In the YMCA and right across the Big Six youth organisations young people have stepped up during the pandemic by delivering supplies to vulnerable people, looking after each other's mental health, making masks, helping share vital public information and now actively facilitating the COVID vaccine campaign. 00:21:35 As the global pandemic enters the recovery and relief period it is crystal-clear that young people are disproportionately impacted by the immediate and long-term implications of disruption in education, employment opportunities, physical and mental health/well-being, to name a few. These two reasons - young people bearing the brunt of the impact of COVID and young people offering so many of the solutions - are what has inspired the Big Six organisations, the World Health Organization and the United Nations Foundation to support young people around the would in delivering and developing youth-led community solutions through the Global Youth mobilisation. I am so excited and I want young people all over the world to be excited and get involved. They can start by attending the Global Youth Summit, which will be held virtually from 23rd to 25th April. At the summit they will hear about the role of young people in the immediate and long-term COVID recovery. It's a great forum where we can share our thoughts, passions, ideas that will influence policies and decisions that impact all of our lives. 00:22:47 This is a critical time for my generation, for our generation to bring policymakers, change-makers, advocate together to address the major challenges confronting young people by solutions and put them into action in our communities. No matter how big or how small I encourage you to have the confidence to apply for funding. If you have an idea to a challenge created by the pandemic you can apply for funding from $500 to $5,000. It is young people like you and me who will evaluate and agree who gets support for these local solutions. So please visit our website, www.globalyouthmobilisation.org We are the movement by youth, for youth and young people really are the answer. We are not the challenge. We are truly being the change that we want to see in the world. Thank you. TAG Thank you. Thank you so much, Daisy - by youth, for youth - and thank you to both of you for your leadership and vision. I look forward to joining both of you at the World Youth Summit and I look forward to seeing what ideas we can help take forward through the Global Youth Mobilisation. This is a reminder that although we're all living through a dark time there are also many reasons for hope and optimism about the future. Christian, back to you. 00:24:24 CL Thank you very much, all, and thank you very much, Dr Tedros. We will start the round of questions and answers. To remind you, if you want to get into the queue for questions please press the raise your hand icon on your screen. We'll start with the first question from Carlos from El Mundo. Carlos, please unmute yourself. CA Hi. CL Go ahead, please. CA It's a question specifically for Greta. Isn't there a risk that the COP26 will lose its momentum? What should we change in the next three months for example to turn the tide and to put the two goals of climate change and vaccination equality on the same level? CL Thank you very much, Carlos. Yes, Greta Thunberg, please. 00:25:27 GT Of course there's a risk that COP will lose momentum but the most important thing is that everyone is safe and of course safety and health come first in these kinds of situations. Of course there's not just one thing that needs to change in order to break this trend that we are seeing now, there's not just one single thing that we can do to - so-called - solve the climate crisis and the vaccine inequity crisis. Of course it's a bit more complicated than that and I think I may not be the best person to answer that. I think there are lots of experts who are more suited for that question but we do need to change our mindsets, we do need to think globally and not only think about ourselves. That's what these crises come down to, that we only think about ourselves, that we don't think about others. They come down to the way we treat others, the way we treat other human beings, the way we treat other animals and nature itself so we need to change our mindsets, if you want one single thing; it's more complicated than but just one thing. CL Thank you very much, Greta. I'll ask Dr Maria Neira from WHO to add, possibly. 00:26:56 MN Thank you, Christian, and thank you very much, Greta. It's really a pleasure to have you with us. You are an inspiration. You have been driving an incredible movement and many people are behind so certainly the COP26 has to be something very successful. In response to your question, Carlos - hola - I think what will change the mindset and what might have an incredible impact is what the Director-General was saying at the beginning, the health argument of climate change. If we are able to explain to people that climate change is about our health, it is affecting our health and if we stop burning fossil fuels the benefits will be enormous in terms of reducing the process of climate change but as well on reducing air pollution. Air pollution, as mentioned again by the Director-General, is responsible for more than seven million premature deaths every year due to exposure to air pollution and in addition to that it creates an environment that makes our health more vulnerable and creates the perfect conditions for more emerging infectious diseases to occur. 00:28:12 So I think we have a perfect case here for creating more action at the COP26, giving the health benefits that can be obtained in an incredible way. If we tackle the causes of air pollution, if we tackle the causes of climate change that will be an enormous health agenda and talking about health is what can make this change that we all need in terms of ambition to go for more at [?] the COP and in convincing people. If we tell people that this is connected to human health I think this will be the final argument that will create much more motivation and engagement and probably a stronger movement to put political pressure on those who will take decisions and hopefully going for much more. Thank you. CL Thank you very much. This was Dr Maria Neira, Director for Environment, Climate Change and Health. The next question goes to Shoko Koyama from NHK. Shoko, please unmute yourself. SH Hello. Can you hear me? CL Go ahead, please. SH Thank you for taking my question. Regarding COVAX, UNICEF is trying to buy one billion syringes by the end of this year in order to distribute to countries together with vaccines. 00:29:37 One billion syringes in addition to the six to 800 million syringes they procure annually seems to be a large quantity. Is COVAX able to procure this huge number of syringes by the end of this year and what challenges are there regarding the procurement of syringes? Thank you. CL Thank you very much, Shoko. I'll give it to Dr Bruce Aylward. BA Thank you very much, Shoko, for the question and thanks for highlighting that it takes more to get the world vaccinated than simply to make and procure the vaccines because there are all the additional pieces that have to go into this including additional supplies like not just syringes, which you mentioned, but also the vaccination cold chains and other supplies that are necessary to keep them in the right conditions before we get them to the actual people who need to be vaccinated. 00:30:38 In terms of the syringes, just like the cold chain equipment the COVAX facility began working with countries way back in October or even earlier last year to look at what numbers of syringes would be required and to start working with manufactures to ensure that pipeline would be there. You might remember some months ago the Director-General invited Henrietta Fore, who is the Executive Director of UNICEF, to join one of these press conferences and at that time she explained what they were already doing to try and make sure that the necessary syringes would be in place. This will continue to be a challenge, just like all of the supplies necessary to get the world vaccinated, these extraordinary numbers but for the moment the pipelines are there and the producers are doing their part. But it all comes back again also to the COVAX facility having the resources it needs so that it can put the contracts in place up-front to make sure the supplies are there, not just the supplies in terms of the vaccines but, exactly as you highlight, the syringes and the other supplies including, as I mentioned, the cold chain equipment and sometimes very specialised cold chain equipment to get these products to people. 00:31:57 CL Thank you very much, Dr Aylward. We'll move on to Robin Mia from AFP. Robin, please unmute yourself. RO Thank you. A question for Greta, if I may. If vaccine inequity carries on and young people start being offered a vaccine in wealthy countries whilst at the same time elderly and wealthy people remain completely unprotected in poor countries, would you advocate a vaccine strike amongst younger people in rich countries until their governments start sharing more vaccines? Thank you. CL Thank you very much, Robin. Of course, Greta, the floor is yours. GT We must not forget that this is not a problem that is caused by individuals. This is a problem that needs to be addressed by the international community, governments and the vaccine developers. It is wrong; if we should start focusing on individuals and urging individuals not to take the vaccine that would send a very wrong message. 00:33:00 Of course everyone who is offered a vaccine should take it but we need to see the bigger picture here and be able to focus on several things at once. So no, I would not advocate for people not to take the vaccine. CL Thank you so much for that. We'll move to Jamil Chad from O Estado de Sao Paulo. Jamil, please unmute yourself. Jamil, do you hear us? Please unmute yourself. JA Can you hear me, Christian? CL Please go ahead. JA Can you hear me? CL Yes. JA Thank you. This is Jamil Chad, a journalist from Brazil. Ms Greta Thunberg, my question is about vaccines but also on climate change. What is your message to President Bolsonaro at this time when both the pandemic is hitting Brazil hard but also climate change is an issue? You'll note very well what is the position of President Bolsonaro. What is the message you can send him today? Thank you. CL Thank you so much, Jamil. Over to Greta. 00:34:24 GT Of course I don't think we should be focusing on talking about individuals since this is a much larger problem but of course Jair Bolsonaro has a huge responsibility both when it comes to the climate, environment and of course we can see the response that Brazil has had during the corona pandemic. I can only speak for myself but I can safely say that he has failed to take the responsibility that is necessary in order to safeguard present and future living conditions for humanity. CL Thank you very much, Greta. We'll move on to Navas Shah from Xinhua. Navas, please unmute yourself. Navas Shah, do you hear us? Please unmute yourself. It looks as if we're not getting to you so we will continue with Gunila Van Hal from Svenska Dagbladet. Gunila, please unmute yourself. GU Can you hear me? CL Wonderful. Go ahead. GU Thanks for taking my question. It is to Greta Thunberg and I'd like to know your view on the proposal from WHO and many governments, among those your own, the Swedish Government, that richer countries should donate remaining vaccine doses to poorer countries once their own risk groups have been vaccinated and before they vaccinate the rest of the population. 00:36:06 What do you think about this and what do you respond to people questioning this, saying, why should we sacrifice our own populations in order to save the world? Thank you. CL Thank you, Gunila. Over to Greta, please. GT I think that is a very reasonable thing to do. We need to protect and prioritise the most vulnerable people in risk groups and working on the front lines, no matter which countries they come from; at least that's my opinion. Of course I understand that people will be frustrated by that. Of course I also want to return to everyday life and everyone I know wants to do that as well but we need to act in solidarity and we need to use common sense when it comes to these issues. As I said, the only sensible thing to do, the only morally right thing to do is to prioritise the people who are the most vulnerable no matter whether they live in a high-income country or a low-income country. 00:37:23 CL Thank you very much, Ms Thunberg. We'll move ahead to Jamie Keaton from AP. Jamie, please unmute yourself. JM Thank you, Christian. My question is both for Ms Thunberg and Ms Moran. What is your message to young people who have become a major driver of COVID-19 infection? We heard the Director-General, Dr Tedros, just mention that increased social mixing among younger adults is possibly one of the reasons for the increase in infections and hospitalisations among people aged 25 to 59. If I could just sneak in a another question to Ms Thunberg, ahead of President Biden's climate summit what do you hope it will achieve? Thank you. CL No small questions today. Thank you very much, Jamie. Let's move to Greta Thunberg first and then on. Thank you. GT Yes, of course it's absolutely crucial that everyone takes our personal responsibility in this crisis. We young people may be the ones who are in general least affected by the virus in a direct way but of course, as I said, we need to act in solidarity with the people in risk groups. 00:38:57 Of course many young people fail to draw that connection maybe; of course not everyone but of course there will always be some. My message to those is that during crises like these we need to take a few steps back and act for the greater good of society and in order to protect our fellow citizens and of course especially people in risk groups because that is the thing you do during crises; you step up for one another. My hopes for the Biden summit; I hope that we will soon in one way or another start treating this crisis like a crisis - the climate crisis, that is - because if we are to be blunt, we can have as many summits as we want, we can have as many meetings and conferences as we want and make nice speeches and nice pledges like next year or 2050 and so on. But as long as those things contain so many loopholes as they do and as long as we are not actually treating the crisis as a crisis of course we won't be able to achieve any major changes. As I mentioned earlier, we need to change our mindsets and we need to change or view of the world. We cannot try to solve this crisis with the same approach that got us into it in the first place so we need to start treating the crisis like a crisis. 00:40:40 Without an increased level of awareness among people in general of course there will be no pressure on world leaders to actually start making the changes that are necessary to safeguard humanity so my hope is that we will start treating the crisis like a crisis. CL Thank you so much, Greta. Let me first give the floor to Daisy Moran from the global youth organisation [unclear]. Daisy. DM Thank you and thank you for your question. I believe my generation, our generation that we are representing is a generation of allyship because we understand our privilege and how to use our privileges to uplift those in the most vulnerable situations. The Global Youth Summit is a platform and a forum for all of youth and stakeholders and supporters to come together to really listen to what are the policy changes that need to be made so that we can have more equitable societies and systems in place. So I hope that you can join us this weekend while we discuss the important issues and challenges facing our generation and how our youth leaders are in a position to create the most innovative solutions to tackle these big issues. Thank you. 00:41:59 CL Thanks so much, Daisy. Now we'll move to Dr Maria Van Kerkhove. MK Thanks, Christian. Those were excellent answers but I did want to clarify something here with regard to increased transmission. We are seeing increased rates of infection across all age groups. Last week there were 5.2 million cases reported to WHO globally, the largest in a single week since this pandemic began, 16 months into the pandemic. That is the largest increase in a week that we have seen to date. We've seen an increase across all age groups. We need to take the blame away and in the question it was meant to blame and we can't do that. Everyone has a role to play in this pandemic. We all have a role to play in keeping ourselves and our loved ones safe. What we are seeing is a slight age shift in some countries driven by social mixing and social mixing doesn't necessarily mean going out and having a party. It means individuals who have to leave their home to go to work, it means individuals have to feed their families and if you increase social mixing for a variety of reasons, whether this is for work or for religious reasons or indeed socialising itself the virus will take advantage of that. 00:43:18 If you add on top of it these variants of concern, variants that are circulating around the world, particularly the B117 variant which is circulating in a large number of countries across the globe that have increased transmissibility; if you add variants that have increased transmissibility with increased mixing this virus will take off and case numbers will increase. In a number of countries we've seen a very, very steep incline due to this. In addition to that we are seeing some countries not able to implement the public health and social measures that are needed to allow for physical distancing and in many parts of the world physical distancing is really not possible but in other parts of the world it is. So we need to do what we can to avoid those crowded settings, avoid those settings where social mixing - particularly indoor, crowded settings where there's poor ventilation, where the virus really likes to spread efficiently between individuals. 00:44:18 We need governments to enable people to carry out those measures; very easy for us to say stay home if you can but we need governments to support individuals to work from home, to stay home if necessary so that we can reduce the possibility for the virus to spread. All of us really have a role to play. Youth, young people, children, young adults are showing us ways in which to be innovative, to remain socially connected yet physically distant. I think what we are seeing with the youth and this youth mobilisation is really energetic. There's a spirit, there's an energy here that is holding leaders accountable and saying, help us help the situation and I'm really inspired to see that. I was really happy to hear the by youth, for youth as you pointed out and showing us that young people, young adults, children can make a significant difference every day. So please let's stop the blame in terms of who is spreading. All of us have a role to play, all of us need to be supported in taking those individual-level measures as well as measures at the family, at the community, at the sub-national, at the international level. 00:45:30 CL Thanks so much, Dr Van Kerkhove. We have Dr Mike Ryan, WHO Health Emergencies Executive Director, to add. MR Thanks, Christian. I just want to reflect on one thing that Daisy said. She said youths are not the problem, youths are the solution and I fundamentally believe in that and thank you, Daisy, for saying that and the energy from everyone today is fantastic. Reflecting on something that Greta said, she spoke about mindset and mindset is everything and Tedros reminds of that every day, I think; it's one of his most common pronouncements about mindset and it doesn't matter what problem you're trying to solve. There's no amount of announcement, there's no amount of recommendations, there's no amount of anything that changes anything until we change our mindset and that can be the mindset about protecting ourselves and our families from COVID and taking precautions. It can be the mindset on government's response to COVID. It can be the mindset driving climate action and reducing climate change. 00:46:37 So I think really we all need to reflect on that. It is our mindsets that drive our behaviour, both positive and negative and they're having a huge impact on the planet and obviously our behaviour's having a huge impact on the trajectory of this pandemic. Thank you. CL Thank you very much, Dr Ryan. The next question in line comes from Isabel Sacco from EFE. Isabel, please unmute yourself. IS Good afternoon, thank you, Christian. I would like to know if you can give us an overview of the proportion of the people under 40 years old who are in ICUs globally or by region. Connected to that, what do we know about mortality among babies? I saw figures from Brazil that indicate that 1,300 babies have died there from COVID. Thank you. CL Thank you very much, Isabel; very detailed questions. Let me give to Dr Maria Van Kerkhove first. MK Thanks for these very important questions. I cannot give you a specific answer of the proportion of those under 40 in ICU but what I can say is that there is an increasing number of hospitalisations among younger individuals and this is driven by what I answered in the last part of the question. 00:48:01 When you have increased transmissibility across all age groups you will see increased rates of hospitalisation, you will see an increased proportion of ICU and you will see increases in death. We are seeing unfortunately a little bit of a shift in the age structure in terms of the median age of individuals who are infected but that is driven by changes in social mixing patterns. If you remember, last spring, in the northern hemisphere's spring we saw a similar situation where as societies were opening up across Europe for example there was an age shift in the median age; it went from an older age group to a slightly younger age group. Again this is driven by people who are leaving their homes to go back to work and if there is the virus that is spreading, if you have virus variants this is a dangerous combination. We are seeing increases in hospitalisation among younger age groups and increased ICU and increased deaths. 00:48:55 With regard to children I did see that report that you mentioned about Brazil. Overall if we look at infection among children, if we look at severity among children still around the world there is a lower proportion of children that experience disease, that experience severe disease and some children do die. If there is a lot of virus that is circulating, if you have millions of cases being reported - and you know so far we've had 140 million cases reported worldwide - we will see deaths in all age groups. With regard to the youngest children, overall they tend to be more mild but again this is not universal. We do see that children, particularly children with underlying conditions but children in general, have died from COVID. So everyone is at risk from this virus. People are at risk of getting infected, at risk of getting severe disease so we do need to do what we can where we can as much as we can to first and foremost prevent infections but also making sure that we use the systems that are in place to get tested, to be able to carry out the public health actions that do prevent the spread from an adult to a child, from a child to an adult; everything that we can to really prevent that level of infection and care for as many people as we can, getting them early into that clinical care pathway to receive the care based on the symptoms that they have. 00:50:28 CL Thank you so much. The next question goes to Akwazi Sarpong from BBC News Africa. Akwazi, please unmute yourself. Akwazi, do you hear us? Yes, please go ahead. AK [Inaudible]. CL Akwazi, the sound is really bad. Please try one more time. AK Yes, [inaudible] in Ghana so [inaudible]. I have two questions. I would like [sound slip] many young people living with disability, particularly visual impairment, have been affected by this virus in Africa and at the global level. The second question is, what programmes are in place to support families with children and young persons with disability and special needs to help us combat this? Thank you. CL Thank you very much, Akwazi; very important questions. I'll hand to Dr Van Kerkhove for a start. 00:51:35 MK I can start. In fact we have departments that are working particularly on persons with disabilities to ensure that persons with disabilities, who are disproportionately affected by COVID-19 in a variety of ways, whether this is about getting the right care, receiving information appropriately so that they know how to keep themselves safe, making sure that they have the ability to receive the materials they need, testing, etc. We have some guidance that is coming out, I hope, today - it was approved yesterday - looking specifically at the more than one billion people worldwide who are living with disabilities, making sure that they have access to vaccination for example. We have seen some innovation in terms of personal protective equipment; if you've noticed, some of the masks for example will have a clear panel so that you can see lips moving for people who have a hearing impairment so there are a number of innovations that are coming online to support individuals with disabilities but also families with disabilities as well because even individuals with disabilities; their caretakers have to be able to care for them. So we need to make sure that those caregivers are protected against the virus as well so there're a number of activities that are underway to ensure those living with disabilities as well as those caring for those with disabilities have the appropriate care and information that they need. 00:53:05 CL Thank you very much, Dr Van Kerkhove. The next question goes to Priti Padnaik from Geneva Health Files. Priti, please unmute yourself. No, Priti lowered her hand apparently in the meantime or we don't find you any more. The next question goes to John Zaracostas from The Lancet. John, please unmute yourself. JO Good afternoon. Can you hear me there? CL Very well. Go ahead. JO I was wondering if you could give me up-to-date estimates on how many vaccine facilities worldwide with excess capacity could be enabled to produce vaccines and secondly, if possible, if Dr Tedros could give us his perspective on what's going on in his homeland where right now they're facing an existential threat. CL Thank you very much. We'll take the first question and I guess we'll see if Mariangela Simao is online... or then... SS I could start. CL Dr Swaminathan; exactly. Please go ahead. SS Thank you. Thank you very much, John, for that question. This is exactly the work that we've started now as part of the COVID vaccine manufacturing taskforce with our COVAX partners, CEPI, GAVI, UNICEF as well as the private sector and regional bodies like the African Union but also other regional organisations. The idea really is to take a short-to-medium-term and a longer-term approach. The short-term and the immediate need is to increase vaccine supplies within the next weeks and months and that can be done by unblocking roadblocks and obstacles that have been identified by the manufacturers and by working with suppliers of those critical ingredients and raw materials so that we can link suppliers and manufacturers as well as work with member states to make sure that export bans and things like that don't interfere with the process of vaccine manufacturing. That's our immediate short-term priority which hopefully will be able to put more doses for COVAX in the coming weeks. The second, more medium-term, is to look at fill and finish capacity to link... 00:55:43 We know that there's a lot of unused fill and finish capacity globally and therefore we need manufacturers who have the capacity to make bulk product and link them with these existing fill and finish capacities in facilities around the world. CEPI already has done a mapping of that and it exists. Then the third, more medium to longer-term, is really to develop new facilities that would build on existing facilities, particularly in low and middle-income countries and get technology transfer, encourage companies. As the DG mentioned, the WHO put out a call on Friday both for owners of technology, particularly MRNA technology to begin with, to come forward to work with us to share that technology, share the know-how and experience with recipient companies that will be selected according to a set of criteria that we are developing. 00:56:40 This will ensure not only supplies for this pandemic - though it may take a few months to get up and running if we start with existing facilities with some expertise - but also will help the future regional health security of regions which currently do not have any manufacturing capacity. This obviously can be extended to vaccines for many other infectious diseases. So that's what the taskforce is looking at and over the coming days we will provide much more detail. Thank you. CL Thank you so much, Dr Swaminathan. I'm calling on Dr Mike Ryan to take the other part. MR Thank you, John; important question. The situation in Tigray in Ethiopia remains very, very dire at the moment. The situation is not improving. We have unpredictable access, increasing humanitarian needs, increasing sexual violence. The response has been hindered by armed clashes throughout the region and many areas are still not receiving food or other assistance. We've got 4.5 million people affected by this crisis. 2.5 million of them have no access to services whatsoever. Half a million people have no access to food. We have a million internally displaced people in 178 sites scattered across the region being served by IOM and UNHCR. 00:58:18 We've had over 800 cases of sexual and gender-based violence reported from just five hospitals alone; that many cases. We've over 62,000 refugees who have crossed into Sudan. That safety valve is very, very difficult to manage and very difficult for us to have access from that side and to support people in the affected area. So, as I said, unpredictable access, displacement, tremendous humanitarian needs but we have 20 health partners working with us who are operational on the ground but they're only accessing about half of the... where aid is concerned. When we look at health facilities, we've done a health facilities survey throughout the region in 264 health facilities. As of now only 72 of those facilities are operational and 40 of those are only partially accessible. 19 hospitals have been completely damaged or destroyed; 15 more with major damage. There're inadequate supply chains across the board. 00:59:23 So the situation in Tigray could not be more dire, the people there could not be in more need of support and help. The situation is deteriorating. The situation is very much a massive concern on a purely humanitarian basis here. There is a health crisis on top of a humanitarian crisis. We're very concerned about malnutrition, about malaria, about cholera, measles, COVID-19 - positivity rates have been rising - and other diseases like meningitis and other diseases that will exploit malnutrition, they will exploit stress and they will exploit all of what's happening in that population. We have resumed surveillance activities but only covering about 30% of the population and again severe, acute malnutrition is a major, major issue. It is very hard to overstate the extent of the humanitarian crisis and the health crisis currently unfolding in Tigray and the WHO and the other UN agencies and NGOs are calling for unfettered humanitarian access and for military conflict and those perpetrating the conflict to remove themselves from civilian areas and those who should not be there should not be there. Thank you. CL Thank you very much. This was Dr Mike Ryan, Executive Director for WHO's Health Emergencies Programme and Dr Bruce Aylward wanted to come in too. 01:00:51 BA Thanks, Christian. I just want to come back to the important point you raised, John, about how much capacity is unused around the world right now because there was huge attention last week at the conference of the African Union on the consultation that was called by the World Trade Organization to try to expand vaccine production globally. But we need to remember that the challenge is how we're actually using the doses that are being made because last week while those conferences were taking place 100 million more doses of vaccine were administered around the world. The issue, John, is where they're being administered because 1% of that 100 million went to low-income countries so 99 million doses of vaccine last week went into high, upper-middle-income and some low-middle-income countries but only 1% of that went to the lowest-income countries. 01:01:48 So every time we bring new capacities online, when we bring new deals online, etc, that you're hearing about we need to ask the question of where those doses are going because those doses are not going to the places that have got the least vaccine today. So we need to be careful in thinking that we can simply build additional capacity because that capacity is still going to the wrong places, quite frankly. While we are giving great attention to how we expand capacity it's going to take weeks and months for that to come online and in the meantime we've got to take some urgent and important decisions about how we are going to use the vaccines that exist today because if we have a lot more weeks where 100, 99% of the vaccine goes to a set of countries that already have most of the vaccine we are not going to get out of this crisis as rapidly and efficiently and with the least lives lost possible. CL Thank you very much for all your answers. With this we're coming to the end of our question-and-answer session. I was very glad to have you all online today and our special guests and I will ask our special guests to start the closing round and we'll go in reverse order. We'll start with Daisy Moran, the Global Youth Mobilisation, Youth [Unclear] and Worldwide YMCA representative. Daisy, please go ahead. 01:03:20 DM Thank you for the opportunity once again and as a reminder, please join us this weekend on April 23rd to 25th to have your voice heard. You have the solutions; please come to the table. We want you to be involved in your local communities and we have the funds to support you. With any questions please visit our website at www.youthglobalmobilisation.org Thank you. CL Fantastic. Thanks so much. Now we go to Elahi Rawshan, volunteer from the International Federation of the Red Cross and Red Crescent Societies, supporting young people in Bangladesh. Elahi, please go ahead. ER Thank you. I would like to thank everyone for inviting me here and I would like to echo the last voice; young people are the solution and I would like to invite all the localised solutions to collaborate with the Global Youth Mobilisation, who have been supporting these local actions and promoting them. 01:04:22 So I would also like to invite everyone to join the Global Youth Summit coming up this week from 23rd to 25th. Thank you once again. CL Thank you so much, Elahi, to you. Last but not least we go to Greta Thunberg, Climate and Environmental Activist. Greta, the floor is yours. GT To be honest I don't really have anything more to add. Just take care, everyone. But also while we have media here, I really urge you to really bring awareness to this issue of vaccine inequity because you have the power to raise awareness about this. When we talk about countries like, for example, the UK and the US - just as a few examples - that they are mass-vaccinating large groups of their populations, even healthier young people, we see it from a different perspective, that we don't always see it from our Western, privileged point of view but rather that we think globally and we need to prioritise those most vulnerable first. Thank you. Take care, everyone. CL Thank you so much, Greta, for these words. Yes, there's hardly anything to add; I agree. From my side let me thank everyone and remind you that the sound files of this press briefing will be shared right afterwards today and the transcript will be available as of tomorrow. Dr Tedros. TAG Thank you. Thank you, Christian. I would like to thank our guests today, Greta, Elahi and Daisy. You have been wonderful. Thank you so much indeed. I would also like to join you in inviting everybody to join on the 23rd to 25th the Global Youth Summit, from Friday to Sunday so I look forward to seeing you there. I would also like to thank our media colleagues who have joined and see you in our upcoming presser. That will be on Friday. Thank you so much. 01:06:54


Assuntos
Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Pandemias/prevenção & controle , Monitoramento Epidemiológico , América/epidemiologia , Quarentena/organização & administração , Isolamento Social , Desenvolvimento Ecológico , Betacoronavirus/imunologia , Vacinas Virais/provisão & distribuição , Acesso a Medicamentos Essenciais e Tecnologias em Saúde , Infecções por Coronavirus/imunologia , Pneumonia Viral/imunologia , Mudança Climática , Doações , Equidade em Saúde , Participação Social , Betacoronavirus/genética , Infecções por Coronavirus/genética , Pneumonia Viral/genética , Mutação/genética , DNA Viral/genética , Sistemas de Saúde/organização & administração , Saúde da Pessoa com Deficiência
15.
BMC Nephrol ; 21(1): 542, 2020 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-33308177

RESUMO

BACKGROUND: Climate change is a significant threat to the health of the Ghanaian people. Evidence abounds in Ghana that temperatures in all the ecological zones are rising, whereas rainfall levels have been generally reducing and patterns are increasingly becoming erratic. The study estimated the impact of climate variation between seasons on biochemical markers of kidney disease. METHODS: This study conveniently recruited 50 apparently healthy peasant farmers and hawkers at Wa in the Upper West Region of Ghana. A pre-study screening for hepatitis A and C, Diabetes mellitus, hypertension was done. Serum creatinine and urea levels were analyzed to rule out kidney preexisting kidney disease. Baseline data was collected by estimating urea, creatinine, sodium, potassium, eGFR (estimated glomerular filtration rate) as well as for hemoglobin (Hb) and hematocrit (Hct) concentrations. Anthropometric data such as height, weight and blood pressure were measured by trained personnel. The study participants were closely followed and alerted deep in the dry season for the second sampling (urea, creatinine, hemoglobin, hematocrit, blood pressure, anthropometry). RESULTS: This study recruited more males (58.82%) than females (41.15%), majority (52.92%) of which were aged 25-29 years with the youngest being 22 years and the eldest being 35 years. The study found body mass index (p < 0.001), systolic blood pressure (p = 0.019), creatinine (p < 0.001), urea (p = 0.013) and eGFR (p < 0.001) to be significantly influenced by climate change. Stage 1 hypertension was predominant among the study participants during the dry season, 8 (15.69%) than was observed during the rainy season, 4 (7.84%) nonetheless the number of participants with normal BMI rose from 49.02% in the rainy season to 62.75% during the dry reason. Additionally, the study observed that the impact of climate change on systolic blood pressure and urea varied based on age and sex. CONCLUSION: This study revealed that climatic changes cause variations in various biochemical parameters used to assess kidney function. Public health education on climatic changes and its implication including precautionary measures should be done among inhabitants of Wa and its environs to reduce its effect. Additionally, appropriate dietary patterns should also be advised to avoid the development of non-communicable diseases such as hypertension and obesity that are known principal causes of Chronic Kidney Disease (CKD).


Assuntos
Pressão Sanguínea , Mudança Climática , Creatinina/sangue , Taxa de Filtração Glomerular , Sobrepeso/epidemiologia , Insuficiência Renal Crônica/sangue , Estações do Ano , Ureia/sangue , Adulto , Índice de Massa Corporal , Feminino , Gana/epidemiologia , Humanos , Estudos Longitudinais , Masculino , Obesidade/epidemiologia , Adulto Jovem
16.
Ying Yong Sheng Tai Xue Bao ; 31(2): 381-387, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32476329

RESUMO

We used tree rings of Pinus tabuliformis sampled in the Muwang National Forest Park to establish a standardized chronology (STD) and calculated the correlation coefficients between the standardized chronology and climatic factors of Zhen'an meteorological station. With linear regression analysis, we reconstructed the March-April mean maximum temperature of Zhen'an over 165 years from 1853 to 2017. The highest correlation coefficient was observed between the standardized chronology and the March-April mean maximum temperature (r=0.596, n=60, P<0.01). The variance interpretation of the March-April mean maximum temperature reconstruction function was 33.2%, and the reconstruction function and results were credible and reliable. Warm years occurred 25 times and cold years occurred 29 times in the reconstruction sequence. The warm years were more accompanied by flood events, while the cold years were accompanied by more drought events. Temperature fluctuated obviously in the reconstruction sequence, with two cold periods (1902-1917 and 1953-2000) and four warm periods (1868-1892, 1917-1937, 1941-1953 and 2001-2012). The obvious periodic variations of 2-7, 8-15, 18-28, 75-96, and 100-125 years were found in the reconstruction sequence, in which the quasi-113, 88 and 22 years were the first, second and third main periods, respectively. These variations might potentially be the fingerprints of some climate change forces such as solar activity, monsoon and EI Niño-Southern Oscillation (ENSO) activity.


Assuntos
Pinus , China , Mudança Climática , Florestas , Temperatura
17.
Tree Physiol ; 40(7): 917-927, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32310277

RESUMO

Past research suggests climate change will cause the climate envelopes of various tree species to shift to higher latitudes and can lead to a northward migration of trees. However, the success and scope of the migration are likely affected by factors that are not contained in the climate envelope, such as photoperiod and interactive effects of multiple environmental factors, and these effects are currently not well understood. In this study, we investigated the interactive effects of CO2 concentrations ([CO2]), photoperiod and soil moisture on the morphological and physiological traits of Populus tremuloides Michx. We grew seedlings under two levels of [CO2] (ambient [CO2] (AC) 400 vs elevated [CO2] (EC) 1000 µmol mol-1), four photoperiod regimes (growing season photoperiods at 48 (seed origin), 52, 55 and 58°N latitude) and two soil moisture regimes (high soil moisture (HSM) vs low soil moisture (LSM), -2 MPa) for two growing seasons in greenhouses. Both morphological and physiological responses were observed. Low soil moisture reduced leaf size, total leaf area and height growth by 33, 46 and 12%, respectively, and increased root/shoot ratio by 20%. The smaller leaf area and increased root/shoot ratio allowed the seedlings in LSM to maintain higher the maximum rate of Rubisco carboxylation (Vcmax) and the maximum rate of electron transport for RuBP regeneration (Jmax) than control seedlings (55 and 83% higher in July, 52 and 70% in August, respectively). Photoperiod and [CO2] modified responses to LSM and LSM altered responses to photoperiod and [CO2], e.g., the August photosynthetic rate was 44% higher in LSM than in HSM under EC but no such a difference existed under AC. The increase in Vcmax and Jmax in response to LSM varied with photoperiod (Vcmax: 36% at 52°N, 22% at 55°N, 47% at 58°N; Jmax: 29% at 52°N, 21% at 55°N, 45% at 58°N). Stomatal conductance and its reduction in response to LSM declined with increasing photoperiod, which can have significant implications for soil moisture effect on northward migration. This study highlights the need to consider the complex interactions of [CO2], photoperiod and soil moisture when planning assisted migration or predicting the natural migration of boreal forests in the future.


Assuntos
Mudança Climática , Secas , Dióxido de Carbono , Fotoperíodo , Fotossíntese , Folhas de Planta , Solo , Árvores
18.
Ecology ; 101(3): e02959, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31850515

RESUMO

Divergent movement strategies have enabled wildlife populations to adapt to environmental change. In recent decades, the Southern Beaufort Sea subpopulation of polar bears (Ursus maritimus) has developed a divergent movement strategy in response to diminishing sea ice where the majority of the subpopulation (73-85%) stays on the sea ice in summer and the remaining bears move to land. Although declines in sea ice are generally considered a challenge to energy balance in polar bears residing in some regions of the Arctic, little quantitative data exists concerning the seasonal energy expenditures of this apex marine carnivore. We used GPS satellite collars with tri-axial accelerometers and conductivity sensors to measure the location, behavior, and energy expenditure of five adult female polar bears in the southern Beaufort Sea across seasons of sea ice breakup and minimum extent. Using a Bayesian mixed-effects model, we found that energy expenditure was influenced by month, ocean depth, and habitat type (sea ice or land). Total energy expenditure from May through September ranged from 37.7 to 47.2 mJ/kg for individual bears. Bears that moved to land expended 7% more energy on average from May through September than bears that remained on the receding sea ice. In August, when bears were moving from the sea ice to land or moving north with the receding pack ice, bears that moved to land spent 7% more time swimming and expended 22% more energy. This means the immediate cost of moving to land exceeded the cost of remaining on the receding summer pack ice. These findings suggest a physiological reason why the majority of the Southern Beaufort Sea subpopulation continues to inhabit a diminishing summer ice platform. However, bears that moved to land spent 29% more time in preferred hunting habitats over the continental shelf than bears that remained on the sea ice. Bears on land also had access to subsistence-harvested bowhead whale carcasses. Hence, our findings indicate there may be a greater overall energetic benefit to move to land in this region, which suggests that the use of the diminishing summer sea ice may be functioning as an ecological trap.


Assuntos
Ursidae , Animais , Regiões Árticas , Teorema de Bayes , Mudança Climática , Feminino , Estações do Ano
19.
Sci Total Environ ; 694: 133784, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31756809

RESUMO

Elevated atmospheric CO2 concentration (eCO2) exerts significant influence on nutrient requirement in plant. The investigation of C:N:P ratios in major cropping soils is important for managing nutrient balance and maximizing their use efficiency in future farming systems. This study aimed to examine the effect of eCO2 on the C:N:P ratios in different plant parts among soybean cultivars. Twenty-four soybean cultivars were planted in open top chambers at two CO2 concentrations (390 and 550 ppm) and sampled at the initial pod filling stage (R5) and the full maturity stage (R8). The C, N and P concentrations in root, stem, leaf and seed were determined. Elevated CO2 decreased the N concentrations in stem (-5.1%) and leaf (-3.2%) at R5, and in root (-24%), stem (-25%) and seed (-6.2%) at R8, resulting in a significant decrease of C:N ratio in the corresponding parts. The P concentration was significantly increased in root (6.0%), stem (7.9%) and leaf (16%) at R5, and in root (2.6%), stem (29%) and seed (16%) at R8 across 24 cultivars, leading to a decrease in the C:P ratio. Elevated CO2 significantly decreased the N:P ratio in root (-4.5%), stem (-12%) and leaf (-17%) at R5, and in root (-26%), stem (-57%) and seed (-22%) at R8. Furthermore, the response of C:N:P ratios to eCO2 varied greatly among soybean cultivars leading to significant CO2 × cultivar interactions. Nitrogen, but not P was the limiting factor for the soybean plants grown in Mollisols under eCO2. The considerable variation in the C:N:P ratios among cultivars in response to eCO2 indicates a potential improvement in soybean adaptability to climate change via selection new cultivars. Cultivars SN22 and ZH4 that did not considerably altered the C:N and C:P ratios in response to eCO2 are likely the optimal genomes in soybean breeding programs for eCO2 adaption.


Assuntos
Dióxido de Carbono/metabolismo , Glycine max/metabolismo , Biomassa , Mudança Climática , Fabaceae , Nitrogênio , Folhas de Planta , Sementes , Solo
20.
Tree Physiol ; 39(11): 1783-1805, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31553458

RESUMO

Global warming is raising concerns about the acclimatory capacity of trees and forests, especially in Mediterranean-type ecosystems. The sensitivity of photosynthesis to temperature is a key uncertainty for projecting the magnitude of terrestrial feedbacks on future climate change. While boreal, temperate and tropical species have been comparatively well investigated, our study provides the first comprehensive overview of the seasonal acclimatory responses of photosynthesis and its component processes to temperature in four Mediterranean climax species under natural conditions. We quantified seasonal changes in the responses of net photosynthesis (Anet), stomatal conductance (gs), mesophyllic conductance (gm) and electron-transport rate (Jcf), and investigated their sensitivity to drought and temperature stress in sunlit and shaded leaves of four Mediterranean tree species (Quercus ilex L., Pinus halepensis Mill., Arbutus unedo L. and Quercus pubescens Willd.). Sunlit leaves, but not shaded leaves, showed a pronounced seasonality in the temperature responses of Anet, gs, gm and Jcf. All four species and variables showed a remarkably dynamic and consistent acclimation of the thermal optimum (Topt), reaching peaks in summer ~29-32 °C. Changes in the shape of the response curves were, however, highly species-specific. Under severe drought, Topt of all variables were on average 22-29% lower. This was accompanied by narrower response curves above all in P. halepensis, reducing the optimal range for photosynthesis to the cooler morning or evening periods. Wider temperature-response curves and less strict stomatal control under severe drought were accompanied by wilting and drought-induced leaf shedding in Q. ilex and Q. pubescens and by additional branch dieback in A. unedo. Mild winter conditions led to a high Topt (~19.1-22.2 °C), benefitting the evergreen species, especially P. halepensis. Seasonal acclimation of Anet was explained better by gs and gm being less pronounced in Jcf. Drought was thus a key factor, in addition to growth temperature, to explain seasonal acclimation of photosynthesis. Severe drought periods may exceed more frequently the high acclimatory capacity of Mediterranean trees to high ambient temperatures, which could lead to reduced growth, increased leaf shedding and, for some species such as A. unedo, increased mortality risk.


Assuntos
Secas , Quercus , Mudança Climática , Ecossistema , Fotossíntese , Folhas de Planta , Temperatura , Árvores
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