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1.
Sci Total Environ ; 927: 172338, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38608897

RESUMO

Algal blooms in lakes have been a challenging environmental issue globally under the dual influence of human activity and climate change. Considerable progress has been made in the study of phytoplankton dynamics in lakes; The long-term in situ evolution of dominant bloom-forming cyanobacteria in meso-eutrophic plateau lakes, however, lacks systematic research. Here, the monthly parameters from 12 sampling sites during the period of 1997-2022 were utilized to investigate the underlying mechanisms driving the superiority of bloom-forming cyanobacteria in Erhai, a representative meso-eutrophic plateau lake. The findings indicate that global warming will intensify the risk of cynaobacteria blooms, prolong Microcystis blooms in autumn to winter or even into the following year, and increase the superiority of filamentous Planktothrix and Cylindrospermum in summer and autumn. High RUETN (1.52 Biomass/TN, 0.95-3.04 times higher than other species) under N limitation (TN < 0.5 mg/L, TN/TP < 22.6) in the meso-eutrophic Lake Erhai facilitates the superiority of Dolichospermum. High RUETP (43.8 Biomass/TP, 2.1-10.2 times higher than others) in TP of 0.03-0.05 mg/L promotes the superiority of Planktothrix and Cylindrospermum. We provided a novel insight into the formation of Planktothrix and Cylindrospermum superiority in meso-eutrophic plateau lake with low TP (0.005-0.07 mg/L), which is mainly influenced by warming, high RUETP and their vertical migration characteristics. Therefore, we posit that although the obvious improvement of lake water quality is not directly proportional to the control efficacy of cyanobacterial blooms, the evolutionary shift in cyanobacteria population structure from Microcystis, which thrives under high nitrogen and phosphorus conditions, to filamentous cyanobacteria adapted to low nitrogen and phosphorus levels may serve as a significant indicator of water quality amelioration. Therefore, we suggest that the risk of filamentous cyanobacteria blooms in the meso-eutrophic plateau lake should be given attention, particularly in light of improving water quality and global warming, to ensure drinking water safety.


Assuntos
Cianobactérias , Eutrofização , Lagos , Temperatura , Lagos/microbiologia , Lagos/química , China , Monitoramento Ambiental , Nitrogênio/análise , Fitoplâncton , Mudança Climática , Estações do Ano , Fósforo/análise , Nutrientes/análise , Aquecimento Global
2.
Environ Sci Pollut Res Int ; 30(43): 97765-97785, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37597144

RESUMO

This study aims to present a multi-perspective evaluation of green concretes produced using supplementary cementitious material and recycled concrete aggregates and to balance the reduction in compressive strength values caused by using recycled concrete aggregates with silica fume. For these purposes, statistical analyses were performed on the response surface method using the data of 9 reference and 27 green concrete series mixtures, and mathematical models were developed to predict the compressive strength with high accuracy. Then, energy consumption, global warming potential, and waste generation were taken into account from the environmental impact categories, and the environmental impact scores obtained were compared in detail to examine the impact of the use of silica fume and recycled concrete aggregates on sustainable development. Significant reductions in energy consumption and global warming potential values with the use of silica fume and waste generation values with the use of recycled concrete aggregates were achieved, and it was seen that supplementary cementitious material and recycled concrete aggregates are of great importance in terms of sustainable development. It was seen that these waste materials could be utilized, especially in regions with high earthquake risk, and that these waste materials are of great importance.


Assuntos
Terremotos , Força Compressiva , Gases , Aquecimento Global , Dióxido de Silício
3.
Food Res Int ; 164: 112318, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36737911

RESUMO

Filamentous fungi serve as potential candidates in the production of different value-added products. In the context of food, there are several advantages of using filamentous fungi for food. Among the main advantages is that the fungal biomass used food not only meets basic nutritional requirements but that it is also rich in protein, low in fat, and free of cholesterol. This speaks to the potential of filamentous fungi in the production of food that can substitute animal-derived protein sources such as meat. Moreover, life-cycle analyses and techno-economic analyses reveal that fungal proteins perform better than animal-derived proteins in terms of land use efficiency as well as global warming. The present article provides an overview of the potential of filamentous fungi as a source of food and food supplements. The commercialization potential as well as social, legal and safety issues of fungi-based food products are discussed.


Assuntos
Dieta Vegana , Fungos , Animais , Humanos , Suplementos Nutricionais , Proteínas Fúngicas/metabolismo , Fungos/metabolismo , Aquecimento Global
4.
Sci Total Environ ; 873: 162313, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36805062

RESUMO

The exclusion of grazing has been used extensively in alpine meadows on the Tibetan Plateau. Studies, however, have shown reported recent trends of decreasing concentrations of soil nutrients because of grazing exclusion and climate change. The effects of excluding grazing on the soil biogeochemical process of phosphorus cycling in alpine meadows are unclear, especially under climatic warming. We conducted a 5-year grazing-exclusion and warming-manipulation experiment to examine the effects of excluding grazing on fractions of soil phosphorus, microbial and nematode communities and enzymatic activities in treatments of low grazing intensity, grazing exclusion, and combined grazing exclusion and warming. Our results indicated that excluding grazing significantly decreased bacterivore and omnivore-predator densities, phoD gene abundance and alkaline phosphomonoesterase activity (in the 0-5 cm layer by -34, -41, -38 and -42 %) at altitudes of 3850 m, 4000 m, 4150 m and 4250 m, respectively. Structural equation modeling indicated that bacterivores positively affected phoD gene abundance, alkaline phosphomonoesterase activity and inorganic­phosphorus fractions. Combined grazing exclusion and warming significantly decreased bacterivore and omnivore-predator densities but significantly increased fungivore density (in the 0-5 cm layer by 238, 172, 119 and 65 %) at altitudes of 3850, 4000, 4150 and 4250 m, respectively. Structural equation modeling also indicated that the combined grazing-exclusion and warming treatment increased the soil fungi and fungivores, but the higher abundances of fungi and fungivores did not significantly affect acid phosphomonoesterase activity or inorganic­phosphorus fractions. Alternatively, the combined grazing-exclusion and warming treatment significantly increased the concentrations of amorphous and free aluminum, which were positively correlated with the maximum adsorption of phosphorus. The combined grazing-exclusion and warming treatment thus significantly decreased the availability of resin phosphorus (-63, -51, -81 and -67 %) in the 0-5 cm layer at altitudes of 3850, 4000, 4150 and 4250 m, respectively. Our results suggested that light grazing (0.5 yak ha-1 year-1) could increase phosphorus mineralization and the activity of soil enzymes in alpine meadows under global warming. An adequate load of livestock pressure at each altitude can be an effective management technique, mainly under warming, to maintain an adequate, sustainable and equilibrated phosphorus cycle in the plant-soil system.


Assuntos
Aquecimento Global , Pradaria , Animais , Tibet , Fósforo , Gado , Cadeia Alimentar , Solo/química , Monoéster Fosfórico Hidrolases
5.
Sci Total Environ ; 846: 157301, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-35839879

RESUMO

Transparent wood, a sustainable material, holds the potential to replace conventional petroleum-based polymers because of its renewable and biodegradable properties. It has been recently used for construction, energy storage, flexible electronics, and packaging applications. Life cycle analysis (LCA) of transparent wood would provide the environmental impacts during its production and end-of-life (EOL). The cradle-to-gate analysis of transparent wood suggests that sodium hydroxide, sodium sulfite, hydrogen peroxide-based delignification (NaOH + Na2SO3 + H2O2 method), and epoxy infiltration lead to the lowest environmental impacts. It generates approximately 24 % less global warming potential and about 15 % less terrestrial acidification than sodium chlorite delignification and polymethyl methacrylate (PMMA) infiltration. The modelled industrial-scale production has lower electricity consumption (by 98.8 %) and environmental impacts than the laboratory scale (28 % less global warming potential and approximately 97 % less human toxicity). The EOL analysis of transparent wood showed reduced ecological impacts (107 times) in comparison to polyethylene, suggesting that it can be commercially adapted to replace conventional petroleum-based materials.


Assuntos
Petróleo , Madeira , Animais , Aquecimento Global , Humanos , Peróxido de Hidrogênio , Estágios do Ciclo de Vida
6.
J Cosmet Dermatol ; 21(9): 3929-3933, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35634686

RESUMO

OBJECTIVE: Cutaneous larva migrans (CLM) is a parasitic disease seen in people in contact with soil in tropical countries. Almost all cases reported in regions without a tropical climate have a history of travel to a tropical region. AIM: In our study, we aimed to investigate the effect of climate change on CLM cases and the demographic characteristics of these cases. For this purpose, the climate information of the period in which we determined the case series and the characteristics of the patients were investigated. MATERIAL AND METHOD: The study was designed retrospectively. Patient files and pre- and post-treatment photographic archives were reviewed retrospectively. In addition, the region's weather history over the last 50 years was examined. RESULTS: The records of patients diagnosed with CLM in 2018 were reviewed retrospectively. In total, 22 cases were detected. The common feature of all cases was that they worked as tea pickers. After examining the weather conditions of the period when the cases were commonly reported, it was determined that there was a sharp temperature increase compared with previous years. CONCLUSION: Due to climate change, an increase in the number of CLM cases is observed in non-tropical regions. Since it is considered a disease-specific to tropical regions, the diagnosis may be overlooked in cases outside these regions. However, CLM should be kept in mind as a diagnostic possibility by clinicians practicing in non-tropical regions as well, especially when treating patients who work with soil, such as tea harvesters.


Assuntos
Dermatologia , Larva Migrans , Mar Negro , Aquecimento Global , Humanos , Larva Migrans/epidemiologia , Estudos Retrospectivos , Solo , Chá , Turquia/epidemiologia
7.
Water Res ; 216: 118301, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35364353

RESUMO

Recent research has shown enhanced biological phosphorus removal (EBPR) from municipal wastewater at warmer temperatures around 30 °C to be achievable in both laboratory-scale reactors and full-scale treatment plants. In the context of a changing climate, the feasibility of EBPR at even higher temperatures is of interest. We operated two lab-scale EBPR sequencing batch reactors for > 300 days at 30 °C and 35 °C, respectively, and followed the dynamics of the communities of polyphosphate accumulating organisms (PAOs) and competing glycogen accumulating organisms (GAOs) using a combination of 16S rRNA gene metabarcoding, quantitative PCR and fluorescence in situ hybridization analyses. Stable and nearly complete phosphorus (P) removal was achieved at 30 °C; similarly, long term P removal was stable at 35 °C with effluent PO43-_P concentrations < 0.5 mg/L on half of all monitored days. Diverse and abundant Candidatus Accumulibacter amplicon sequence variants were closely related to those found in temperate environments, suggesting that EBPR at this temperature does not require a highly specialized PAO community. A slow-feeding strategy effectively limited the carbon uptake rates of GAOs, allowing PAOs to outcompete GAOs at both temperatures. Candidatus Competibacter was the main GAO, along with cluster III Defluviicoccus members. These organisms withstood the slow-feeding regime, suggesting that their bioenergetic characteristics of carbon uptake differ from those of their tetrad-forming relatives. Comparative cycle studies revealed higher carbon and P cycling activity of Ca. Accumulibacter when the temperature was increased from 30 °C to 35 °C, implying that the lowered P removal performance at 35 °C was not a direct effect of temperature, but a result of higher metabolic rates of carbon (and/or P) utilization of PAOs and GAOs, the resultant carbon deficiency, and escalated community competition. An increase in the TOC-to-PO43--P ratio (from 25:1 to 40:1) effectively eased the carbon deficiency and benefited PAOs. In general, a slow-feeding strategy and sufficiently high carbon input benefited a high and stable EBPR at 35 °C, representing basic conditions suitable for full-scale treatment plants experiencing higher water temperatures.


Assuntos
Betaproteobacteria , Fósforo , Betaproteobacteria/metabolismo , Reatores Biológicos , Carbono , Estudos de Viabilidade , Aquecimento Global , Glicogênio/metabolismo , Hibridização in Situ Fluorescente , Fósforo/metabolismo , Polifosfatos/metabolismo , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo
8.
J Environ Manage ; 310: 114810, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35240566

RESUMO

Used cooking oil (UCO) is a valuable resource that can be utilized in different ways. Appropriate management of UCO waste can provide environmental and economic benefits, compared to improper disposal practices. This study assessed the environmental impacts of potential UCO valorization options in Thailand. Altogether, 14 scenarios, including 10 for alternative energy recovering processes (S1-10) and other options such as soap production (S11), use in dry pig feed (DPF) production (S12), synthesis of plastics (S13) and polyol (S14), were considered. The defined system boundaries for each scenario include pretreatment, material and energy consumption, and waste treatment stages for the treatment of 1000 kg UCO. Environmental impacts in terms of global warming potential (GWP), freshwater eutrophication potential (FEP), fossil resource scarcity (FRS), and freshwater, terrestrial, and marine eco-toxicity (FE, TE, and ME, respectively) were analyzed using the ReCiPe Midpoint (H) method. The results revealed that all the current waste valorization options create an environmental burden and contribute towards GWP. Scenarios 7 and 10 showed environmental credits for FEP, FE, and ME indicators while scenario 9 did so for FRS. The processes direct energy consumption resulted in the highest contribution to GWP in Scenarios 1, 5-8, 10, 12, and 13. Environmental effects of material consumption and waste treatments were found to be the highest in bio-oil and DPF production, respectively. However, co-products produced could not offset the burden created by energy and material consumption. Overall, the results showed better environmental performance from energy recovery-based UCO management options compared to alternative processes.


Assuntos
Óleos de Plantas , Eliminação de Resíduos , Gerenciamento de Resíduos , Animais , Culinária , Meio Ambiente , Eutrofização , Aquecimento Global , Suínos , Tailândia
9.
Waste Manag ; 140: 225-232, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34838375

RESUMO

Fruit and vegetable waste (FVW) contains rich resources that can be recovered by methods such as incineration, anaerobic digestion to generate heat energy, biogas, and preservation by ensiling. However, a horizontal comparison of the resource potential and environmental impact of different recycling methods employed for FVW has not been conducted. This study quantifies and computes the recycling potential and global warming potential (GWP) of anaerobic digestion, ensiling, and incineration of the FVW generated during primary production in China. First, a gray model was employed to estimate the FVW output in 2030, based on the FVW produced between 2002 and 2017. Next, the resource potential and GWP of anaerobic digestion, incineration, and ensiling were evaluated. Finally, an optimization method was utilized to analyze possible strategies of FVW recycling in 2030. Results indicate that FVW output in China is expected to increase to 170 Mt by 2030, highlighting the need for efficient treatment options. Further, the resource potential and GWP of different waste treatment strategies were notably different. The recycling potential of ensiling was the highest at 1950 MJ/t; while the GWP of anaerobic digestion was the lowest at -31 kg CO2eq. An optimization analysis suggested that the optimal target of 100% would be attained if all FVW is ensiled in 2030. The study provides a basis for informed technical decision-making related to FVW recycling options in the future.


Assuntos
Eliminação de Resíduos , Verduras , Anaerobiose , Reatores Biológicos , Frutas , Aquecimento Global
10.
Sci Total Environ ; 795: 148850, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34246141

RESUMO

Orchidaceae are among the most endangered plants in the world. Considering the sensitive nature of pollinator-plant relationship the most vulnerable are species which are dependent on a single pollen vector. In this paper the future distribution of suitable niches of Australian sexually deceptive orchid Leporella fimbriata and its pollinator (Myrmecia urens) was estimated using three machine learning algorithms. While the potential range of fringed hare orchid depending on modelling method will be larger or slightly reduced than currently observed, the ant will face significant loss of suitable niches. As a result of global warming the overlap of orchid and its only pollen vector will most probably decrease. The unavailability of pollen vector will lead to decreased reproductive success and as a result it will be a great threat for L. fimbriata existence.


Assuntos
Orchidaceae , Polinização , Austrália , Flores , Aquecimento Global , Pólen
11.
Environ Res ; 201: 111583, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34192557

RESUMO

Projections show that Earth's climate will continue to warm concurrent with increases in the percentage of the world's elderly population. With an understanding that the body's resilience to the heat degrades as it ages, these coupled phenomena point to serious concerns of heat-related mortality in growing elderly populations. As many of the people in this age cohort choose to live in managed long-term care facilities, it's imperative that outdoor spaces of these communities be made thermally comfortable so that connections with nature and the promotion of non-sedentary activities are maintained. Studies have shown that simply being outside has a positive impact on a broad range of the psychosocial well-being of older adults. However, these spaces must be designed to afford accessibility, safety, and aesthetically pleasing experiences so that they are taken full advantage of. Here, we employ an integrative review to link ideas from the disciplines of climate science, health and physiology, and landscape architecture to explain the connections between heat, increased morbidity and mortality in aging adults, existing gaps in thermal comfort models, and key strategies in the development of useable, comfortable outdoor spaces for older adults. Integrative reviews allow for new frameworks or perspectives on a subject to be introduced. Uncovering the synergy of these three knowledge bases can contribute to guiding microclimatic research, design practitioners, and care providers as they seek safe, comfortable and inviting outdoor spaces for aging adults.


Assuntos
Aquecimento Global , Assistência de Longa Duração , Microclima , Idoso , Regulação da Temperatura Corporal , Atenção à Saúde , Humanos
12.
PLoS One ; 16(2): e0246433, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33529264

RESUMO

As the two limiting nutrients for plants in most terrestrial ecosystems, nitrogen (N) and phosphorus (P) are essential for the development of succession forests. Vegetation N:P stoichiometry is a useful tool for detecting nutrient limitation. In the present work, chronosequence analysis was employed to research N and P accumulation dynamics and their stoichiometry during forest primary succession in a glacier retreat area on the Tibetan Plateau. Our results showed that: (1) total ecosystem N and P pools increased from 97 kg hm-2 to 7186 kg hm-2 and 25 kg hm-2 to 487 kg hm-2, respectively, with increasing glacier retreat year; (2) the proportion of the organic soil N pool to total ecosystem N sharply increased with increasing glacier retreat year, but the proportion of the organic soil and the vegetation P pools to the total ecosystem P was equivalent after 125 y of recession; (3) the N:P ratio for tree leaves ranged from 10.1 to 14.3, whereas the N:P ratio for total vegetation decreased form 13.3 to 8.4 and remained constant after 35 y of recession, and the N:P ratio for organic soil increased from 0.2 to 23.1 with increasing glacier retreat. These results suggested that organic soil N increased with increasing years of glacier retreat, which may be the main sink for atmospheric N, whereas increased P accumulation in vegetation after 125 y of recession suggested that much of the soil P was transformed into the biomass P pool. As the N:P ratio for vegetation maintained a low level for 35-125 y of recession, we suggested that N might be the main limiting element for plant growth in the development of this ecosystem.


Assuntos
Aquecimento Global , Camada de Gelo , Nitrogênio/análise , Fósforo/análise , Solo/química , Árvores/química , Biomassa , Ecossistema , Florestas , Tibet
13.
Commun Biol ; 4(1): 176, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33564110

RESUMO

A major climate shift took place about 40 Myr ago-the Middle Eocene Climatic Optimum or MECO-triggered by a significant rise of atmospheric CO2 concentrations. The biotic response to this MECO is well documented in the marine realm, but poorly explored in adjacent landmasses. Here, we quantify the response of the floras from America's southernmost latitudes based on the analysis of terrestrially derived spores and pollen grains from the mid-late Eocene (~46-34 Myr) of southern Patagonia. Robust nonparametric estimators indicate that floras in southern Patagonia were in average ~40% more diverse during the MECO than pre-MECO and post-MECO intervals. The high atmospheric CO2 and increasing temperatures may have favored the combination of neotropical migrants with Gondwanan species, explaining in part the high diversity that we observed during the MECO. Our reconstructed biota reflects a greenhouse world and offers a climatic and ecological deep time scenario of an ice-free sub-Antarctic realm.


Assuntos
Dinoflagellida , Fósseis , Sedimentos Geológicos/análise , Aquecimento Global , Efeito Estufa , Plantas , Pólen , Esporos , Biota , Dióxido de Carbono/análise , Gases de Efeito Estufa/análise , América do Sul , Fatores de Tempo
14.
Nat Commun ; 12(1): 570, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33495440

RESUMO

Melting of the Greenland Ice Sheet is a leading cause of land-ice mass loss and cryosphere-attributed sea level rise. Blooms of pigmented glacier ice algae lower ice albedo and accelerate surface melting in the ice sheet's southwest sector. Although glacier ice algae cause up to 13% of the surface melting in this region, the controls on bloom development remain poorly understood. Here we show a direct link between mineral phosphorus in surface ice and glacier ice algae biomass through the quantification of solid and fluid phase phosphorus reservoirs in surface habitats across the southwest ablation zone of the ice sheet. We demonstrate that nutrients from mineral dust likely drive glacier ice algal growth, and thereby identify mineral dust as a secondary control on ice sheet melting.


Assuntos
Eutrofização/fisiologia , Camada de Gelo , Microalgas/crescimento & desenvolvimento , Minerais/metabolismo , Fósforo/metabolismo , Biomassa , Ecossistema , Congelamento , Geografia , Aquecimento Global , Groenlândia , Gelo , Microalgas/citologia , Microalgas/ultraestrutura , Microscopia Eletrônica de Varredura , Estações do Ano
15.
PLoS One ; 15(12): e0242331, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33296368

RESUMO

The Toarcian Oceanic Anoxic Event (TOAE; Early Jurassic, ca. 182 Ma ago) represents one of the major environmental disturbances of the Mesozoic and is associated with global warming, widespread anoxia, and a severe perturbation of the global carbon cycle. Warming-related dysoxia-anoxia has long been considered the main cause of elevated marine extinction rates, although extinctions have been recorded also in environments without evidence for deoxygenation. We addressed the role of warming and disturbance of the carbon cycle in an oxygenated habitat in the Iberian Basin, Spain, by correlating high resolution quantitative faunal occurrences of early Toarcian benthic marine invertebrates with geochemical proxy data (δ18O and δ13C). We find that temperature, as derived from the δ18O record of shells, is significantly correlated with taxonomic and functional diversity and ecological composition, whereas we find no evidence to link carbon cycle variations to the faunal patterns. The local faunal assemblages before and after the TOAE are taxonomically and ecologically distinct. Most ecological change occurred at the onset of the TOAE, synchronous with an increase in water temperatures, and involved declines in multiple diversity metrics, abundance, and biomass. The TOAE interval experienced a complete turnover of brachiopods and a predominance of opportunistic species, which underscores the generality of this pattern recorded elsewhere in the western Tethys Ocean. Ecological instability during the TOAE is indicated by distinct fluctuations in diversity and in the relative abundance of individual modes of life. Local recovery to ecologically stable and diverse post-TOAE faunal assemblages occurred rapidly at the end of the TOAE, synchronous with decreasing water temperatures. Because oxygen-depleted conditions prevailed in many other regions during the TOAE, this study demonstrates that multiple mechanisms can be operating simultaneously with different relative contributions in different parts of the ocean.


Assuntos
Distribuição Animal , Organismos Aquáticos/fisiologia , Extinção Biológica , Aquecimento Global/história , Invertebrados/fisiologia , Animais , Ciclo do Carbono , Fósseis , Geografia , Sedimentos Geológicos , História Antiga , Temperatura Alta/efeitos adversos , Oceanos e Mares , Espanha
16.
Philos Trans A Math Phys Eng Sci ; 378(2181): 20190358, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-32862806

RESUMO

The Arctic Ocean region is currently undergoing dramatic changes, which will likely alter the nutrient cycles that underpin Arctic marine ecosystems. Phosphate is a key limiting nutrient for marine life but gaps in our understanding of the Arctic phosphorus (P) cycle persist. In this study, we investigate the benthic burial and recycling of phosphorus using sediments and pore waters from the Eurasian Arctic margin, including the Barents Sea slope and the Yermak Plateau. Our results highlight that P is generally lost from sediments with depth during organic matter respiration. On the Yermak Plateau, remobilization of P results in a diffusive flux of P to the seafloor of between 96 and 261 µmol m-2 yr-1. On the Barents Sea slope, diffusive fluxes of P are much larger (1736-2449 µmol m-2 yr-1), but these fluxes are into near-surface sediments rather than to the bottom waters. The difference in cycling on the Barents Sea slope is controlled by higher fluxes of fresh organic matter and active iron cycling. As changes in primary productivity, ocean circulation and glacial melt continue, benthic P cycling is likely to be altered with implications for P imported into the Arctic Ocean Basin. This article is part of the theme issue 'The changing Arctic Ocean: consequences for biological communities, biogeochemical processes and ecosystem functioning'.


Assuntos
Camada de Gelo/química , Fósforo/análise , Regiões Árticas , Difusão , Ecossistema , Sedimentos Geológicos/química , Aquecimento Global , Ferro/análise , Noruega , Compostos Orgânicos/análise , Estações do Ano , Água do Mar/química
17.
Can J Public Health ; 111(6): 897-900, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32761545

RESUMO

Indigenous peoples have long been successful at adapting to climatic and environmental changes. However, anthropogenic climatic crisis represents an epoch of intensified colonialism which poses particular challenges to Indigenous peoples throughout the world, including those in wealthier 'modern' nation states. Indigenous peoples also possess worldviews and traditional knowledge systems that are critical to climate mitigation and adaptation, yet, paradoxically, these are devalued and marginalized and have yet to be recognized as essential foundations of public health. In this article, we provide an overview of how public health policy and discourse fails Indigenous peoples living in the colonial nation states of Canada and Aotearoa New Zealand. We argue that addressing these systemic failures requires the incorporation of Indigenous knowledges and Indigenous feminist perspectives beyond superficial understandings in public health-related climate change policy and practice, and that systems transformation of this nature will in turn require a radical revision of settler understandings of the determinants of health. Further, public health climate change responses that centre Indigenous knowledges and Indigenous feminist perspectives as presented by Indigenous peoples themselves must underpin from local to global levels.


RéSUMé: Les peuples autochtones ont de tout temps réussi à s'adapter aux changements du climat et de leur environnement. La crise climatique anthropogène constitue toutefois une époque de colonialisme intensifié qui pose des difficultés particulières aux peuples autochtones du monde entier, y compris ceux des États-nations riches et « modernes ¼. Les peuples autochtones possèdent aussi des visions du monde et des systèmes de savoir traditionnels indispensables aux efforts d'atténuation et d'adaptation au changement climatique; paradoxalement, ces visions et systèmes sont dévalués et marginalisés et ne sont pas encore reconnus comme étant des bases essentielles de la santé publique. Dans cet article, nous expliquons en général en quoi les politiques et le discours de la santé publique laissent sur le carreau les peuples autochtones vivant dans les États-nations coloniaux du Canada et d'Aotearoa (la Nouvelle-Zélande). Nous faisons valoir que pour aborder ces échecs systémiques, il faut intégrer les savoirs autochtones et les perspectives féministes autochtones au-delà d'une compréhension superficielle des politiques et des pratiques de santé publique relatives au changement climatique, et qu'une telle transformation des systèmes exigera en retour une révision radicale des savoirs coloniaux sur les déterminants de la santé. Plus encore, les ripostes de la santé publique au changement climatique, que ce soit à l'échelle locale ou mondiale, doivent être centrées sur les savoirs autochtones et les perspectives féministes autochtones tels que présentés par les peuples autochtones eux-mêmes.


Assuntos
Aquecimento Global , Povos Indígenas , Saúde Pública , Política Pública , Feminismo , Humanos , Povos Indígenas/psicologia , Conhecimento
18.
Sci Total Environ ; 742: 140667, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32721755

RESUMO

Potato is one of the most important food crops in South Korea, but the climate change impact on potato production is not clearly understood due to the complex topography across the nation. The climate change impact on spring potato was assessed with a fine-resolution (1-km) simulation using the SUBSTOR-potato model and five regional climate models based on the Representative Concentration Pathways 8.5. Compared to the current climate, the future climates were projected to be more favorable for the spring potato production, which contrasts the previous simulation studies using general circulation models with coarse resolutions (0.5-1.0°). Without any adaptations, anticipated warming was projected to decrease potato yield by -7.7% in the 2080s. However, growing season length (GSL) could be extended by 18.5 days with earlier planting, which eventually over-compensated the negative warming effect. With consideration of the CO2 fertilization effect, overall climate change impact could be up to +80% in the 2080s. In addition, replacing the current early cultivar "Superior" with mid-late cultivars will provide additional yield gain in the coastal areas. Meanwhile, in the inland areas, breeding of frost- and heat-tolerance cultivars will be required for additional yield gain. Still, cautious interpretation is needed since the CO2 fertilization effect might be over-estimated and that the farmers may not extend GSL as much as in the current study from the economic point of view (i.e., farmers may harvest earlier when the market price of potato is high). This study highlights that a fine spatial resolution is essential for the realistic simulation of the climate change impact in complex terrain.


Assuntos
Solanum tuberosum , Mudança Climática , Aquecimento Global , República da Coreia , Estações do Ano
19.
Nature ; 578(7795): 409-412, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32076219

RESUMO

Atmospheric methane (CH4) is a potent greenhouse gas, and its mole fraction has more than doubled since the preindustrial era1. Fossil fuel extraction and use are among the largest anthropogenic sources of CH4 emissions, but the precise magnitude of these contributions is a subject of debate2,3. Carbon-14 in CH4 (14CH4) can be used to distinguish between fossil (14C-free) CH4 emissions and contemporaneous biogenic sources; however, poorly constrained direct 14CH4 emissions from nuclear reactors have complicated this approach since the middle of the 20th century4,5. Moreover, the partitioning of total fossil CH4 emissions (presently 172 to 195 teragrams CH4 per year)2,3 between anthropogenic and natural geological sources (such as seeps and mud volcanoes) is under debate; emission inventories suggest that the latter account for about 40 to 60 teragrams CH4 per year6,7. Geological emissions were less than 15.4 teragrams CH4 per year at the end of the Pleistocene, about 11,600 years ago8, but that period is an imperfect analogue for present-day emissions owing to the large terrestrial ice sheet cover, lower sea level and extensive permafrost. Here we use preindustrial-era ice core 14CH4 measurements to show that natural geological CH4 emissions to the atmosphere were about 1.6 teragrams CH4 per year, with a maximum of 5.4 teragrams CH4 per year (95 per cent confidence limit)-an order of magnitude lower than the currently used estimates. This result indicates that anthropogenic fossil CH4 emissions are underestimated by about 38 to 58 teragrams CH4 per year, or about 25 to 40 per cent of recent estimates. Our record highlights the human impact on the atmosphere and climate, provides a firm target for inventories of the global CH4 budget, and will help to inform strategies for targeted emission reductions9,10.


Assuntos
Atmosfera/química , Combustíveis Fósseis/história , Combustíveis Fósseis/provisão & distribuição , Atividades Humanas/história , Metano/análise , Metano/história , Biomassa , Radioisótopos de Carbono , Carvão Mineral/história , Carvão Mineral/provisão & distribuição , Aquecimento Global/prevenção & controle , Aquecimento Global/estatística & dados numéricos , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , Camada de Gelo/química , Metano/química , Gás Natural/história , Gás Natural/provisão & distribuição , Petróleo/história , Petróleo/provisão & distribuição
20.
Int Nurs Rev ; 67(1): 4-6, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32083728

RESUMO

The next decade is likely to produce any number of global challenges that will affect health and health care, including pan-national infections such as the new coronavirus COVID-19 and others that will be related to global warming. Nurses will be required to react to these events, even though they will also be affected as ordinary citizens. The future resilience of healthcare services will depend on having sufficient numbers of nurses who are adequately resourced to face the coming challenges.


Assuntos
Atenção à Saúde , Tocologia , Enfermeiros Obstétricos , COVID-19 , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/enfermagem , Atenção à Saúde/tendências , Feminino , Saúde Global , Aquecimento Global , Humanos , Pneumonia Viral/epidemiologia , Pneumonia Viral/enfermagem , Gravidez
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