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1.
Chemosphere ; 261: 127769, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32738716

RESUMO

The characteristics of secondary inorganic aerosol including sulfate, nitrate and ammonium (SNA) were investigated during a six-month long heating season in the Harbin-Changchun metropolitan area, i.e., China's only national-level city cluster located in the severe cold climate region. The contribution of SNA to fine particulate matter (PM2.5) tended to decrease with increasing PM2.5 concentration, opposite to the trend repeatedly observed during winter in Beijing. Heterogeneous sulfate formation was still evident when the daily average temperature was as low as below -10 °C, with the preconditions of high relative humidity (RH; above ∼80%) and high nitrogen dioxide (above ∼60 µg/m3). Both the sulfur oxidation ratio (SOR) and nitrogen oxidation ratio (NOR) were enhanced at high RH, reaching ∼0.3. However, the high RH conditions were not commonly seen during the heating season, which should be responsible for the overall lack of linkage between the SNA contribution and PM2.5 temporal variation.


Assuntos
Poluentes Atmosféricos/análise , Clima Frio , Monitoramento Ambiental , Aerossóis/análise , Pequim , China , Cidades , Calefação , Umidade , Nitratos/análise , Dióxido de Nitrogênio , Óxidos de Nitrogênio/análise , Material Particulado/análise , Estações do Ano , Sulfatos/análise
2.
BMC Ecol ; 20(1): 32, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32493329

RESUMO

BACKGROUND: Resolving the preferred prey items and dietary proportions of leopard seals is central to understanding food-web dynamics in the rapidly-warming Antarctic Peninsula region. Previous studies have identified a wide range of prey items; however, due to anecdotal or otherwise limited information, leopard seal diets remain unresolved by seal sex, individual, body size, region, and season. Over the 2013, 2014, and 2017 field seasons we collected scat, tissue samples (red blood cells and plasma; n = 23) for stable isotope analyses, and previously-reported animal-borne video from 19 adult leopard seals foraging near mesopredator breeding colonies at Cape Shirreff, Livingston Island. We summarized a priori diet information from scat and video analysis and applied a three-isotope (δ13C, δ15N, δ34S), four-source (fish, fur seal, krill, penguin) Bayesian mixing model to examine temporal variability in both prey sources and leopard seal tissues. RESULTS: The austral spring diets of males and females focused on Antarctic krill (31.7-38.0%), notothen fish (31.6-36.5%), and penguin (24.4-26.9%) and were consistent across all 3 years. Several lines of evidence suggest the transition to summer foraging was distinct for males and females. Female diets transitioned rapidly to higher δ15N values (+2.1‰), indicating increased consumption of penguin (29.5-46.2%) and energy-dense Antarctic fur seal pup (21.3-37.6%). CONCLUSIONS: The seasonal increase in leopard seal δ15N values, and thus fur seal in their diet, was predictably related to larger body size; it may also be forcing reductions to the largest Antarctic fur seal colony in the Antarctic Peninsula. Our ensemble sampling approach reduces historical biases in monitoring marine apex predator diets. Further, our results are necessary to best inform regional fisheries management planning.


Assuntos
Dieta , Focas Verdadeiras , Animais , Regiões Antárticas , Teorema de Bayes , Tamanho Corporal , Clima Frio , Feminino , Masculino , Comportamento Predatório , Estações do Ano
3.
Proc Natl Acad Sci U S A ; 117(27): 15443-15449, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32571905

RESUMO

The assassination of Julius Caesar in 44 BCE triggered a power struggle that ultimately ended the Roman Republic and, eventually, the Ptolemaic Kingdom, leading to the rise of the Roman Empire. Climate proxies and written documents indicate that this struggle occurred during a period of unusually inclement weather, famine, and disease in the Mediterranean region; historians have previously speculated that a large volcanic eruption of unknown origin was the most likely cause. Here we show using well-dated volcanic fallout records in six Arctic ice cores that one of the largest volcanic eruptions of the past 2,500 y occurred in early 43 BCE, with distinct geochemistry of tephra deposited during the event identifying the Okmok volcano in Alaska as the source. Climate proxy records show that 43 and 42 BCE were among the coldest years of recent millennia in the Northern Hemisphere at the start of one of the coldest decades. Earth system modeling suggests that radiative forcing from this massive, high-latitude eruption led to pronounced changes in hydroclimate, including seasonal temperatures in specific Mediterranean regions as much as 7 °C below normal during the 2 y period following the eruption and unusually wet conditions. While it is difficult to establish direct causal linkages to thinly documented historical events, the wet and very cold conditions from this massive eruption on the opposite side of Earth probably resulted in crop failures, famine, and disease, exacerbating social unrest and contributing to political realignments throughout the Mediterranean region at this critical juncture of Western civilization.


Assuntos
Mudança Climática/história , Clima Frio/efeitos adversos , Desastres/história , Mundo Romano/história , Erupções Vulcânicas/efeitos adversos , Alaska , Clima , Produtos Agrícolas/história , Fome Epidêmica/história , História Antiga , Camada de Gelo , Região do Mediterrâneo , Política , Erupções Vulcânicas/história
4.
Nat Commun ; 11(1): 2529, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32439857

RESUMO

Climate warming is anticipated to make high latitude ecosystems stronger C sinks through increasing plant production. This effect might, however, be dampened by insect herbivores whose damage to plants at their background, non-outbreak densities may more than double under climate warming. Here, using an open-air warming experiment among Subarctic birch forest field layer vegetation, supplemented with birch plantlets, we show that a 2.3 °C air and 1.2 °C soil temperature increase can advance the growing season by 1-4 days, enhance soil N availability, leaf chlorophyll concentrations and plant growth up to 400%, 160% and 50% respectively, and lead up to 122% greater ecosystem CO2 uptake potential. However, comparable positive effects are also found when insect herbivory is reduced, and the effect of warming on C sink potential is intensified under reduced herbivory. Our results confirm the expected warming-induced increase in high latitude plant growth and CO2 uptake, but also reveal that herbivorous insects may significantly dampen the strengthening of the CO2 sink under climate warming.


Assuntos
Betula/metabolismo , Sequestro de Carbono , Florestas , Aquecimento Global , Herbivoria/fisiologia , Insetos/fisiologia , Animais , Betula/crescimento & desenvolvimento , Dióxido de Carbono/metabolismo , Clima Frio , Ecossistema , Nitrogênio/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Solo/química , Tempo (Meteorologia)
5.
Environ Int ; 139: 105704, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32278194

RESUMO

Plastic marine pollution in the Arctic today illustrates the global distribution of plastic waste of all sizes traveling by wind and waves, entering food chains, and presenting challenges to management and mitigation. While currents move plastics from lower latitudes into the Arctic, significant waste is also generated by remote communities, as well as maritime activities, such as shipping, fishing and tourism, which are increasing their activities as seasonal sea ice diminishes. Mitigation strategies may include monitoring programs of plastic waste abundance and distribution, improved waste management in Arctic communities, Extended Producer Responsibility (EPR) to reverse the transport of waste plastics and packaging from remote communities, incentivized gear recovery of abandoned, lost and discarded fishing gear (ALDFG), gear tagging and tracking, and restricting tourism and employing "leave no trace" policies. Here we report how these mitigation strategies are employed in the Arctic to minimize plastic waste impacts, and move Arctic communities toward better materials management and circular economic practices. The evidence of harm from waste plastics exacerbated by the ubiquity of plastic marine pollution in all biomes, and the rapid reporting of ecological and social costs, together suggest that we know enough to act quickly to manage and mitigate plastics from all sources to the Arctic.


Assuntos
Plásticos , Gerenciamento de Resíduos , Regiões Árticas , Clima Frio , Monitoramento Ambiental , Poluição Ambiental , Resíduos/análise
6.
Environ Sci Pollut Res Int ; 27(17): 21716-21732, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32279260

RESUMO

Cities have turned to permeable pavements as one tool to mitigate the detrimental effects of urban runoff. Permeable pavements permit rainfall to infiltrate through a series of aggregate layers, where pollutants are filtered out before the water discharges via an underdrain or exfiltrates into native soils. This study reports on the water quality performance of a parking area retrofitted with permeable interlocking concrete pavement in Vermilion, OH, USA. The practice was constructed in 2015, received run-on from an asphalt traffic lane and was operational for 2 years before the onset of monitoring. During the 15-month monitoring period, the permeable pavement provided significant reductions of sediment and particulate nutrients, which were removed via filtration in the upper aggregate layers. Despite poorly draining underlying soils, runoff volumes were reduced by 26%, leading to significant load reductions for nearly all nutrient and heavy metals in the study. Seasonal variations in runoff and effluent composition were investigated, showing that restorative maintenance performed in spring and fall has the potential to further improve the treatment provided by the practice by removing entrained particulates from the upper aggregate layers and restoring the filtering capacity of the system. Correlation analyses revealed a first flush of particulate nitrogen species, as well as the potential occurrence of erosive flows within the aggregate subbase which resulted in elevated sediment concentrations during high intensity rain events. Results from this study demonstrate the effectiveness of permeable pavements several years after construction, even when design features to specifically improve treatment were not implemented and additional run-on is routed onto the pavement from adjacent impervious surfaces. Findings also highlight the importance of timely maintenance of these practices, which could further improve their performance by removing seasonally deposited pollutants throughout the year.


Assuntos
Clima Frio , Movimentos da Água , Cidades , Hidrocarbonetos , Chuva
7.
Sci Total Environ ; 727: 138620, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32315903

RESUMO

Willow wetlands can offer a low-cost solution for recovery of nutrients contained in sewage water and simultaneously produce plant biomass, which can be used in energy production. Willow (Salix spp.) is considered an excellent crop for this purpose, due to its good nutrient uptake and biomass production. Although willow wetlands have been used in sewage treatment in e.g. Denmark, Sweden and southern Finland, their use in northern regions is challenging due to the detrimental effects cold climate conditions can have on plant survival rates and wastewater purification efficiency. In this study, a pilot constructed wetland in northern Finland receiving effluent from a small-scale wastewater treatment plant was investigated. Four willow varieties were planted (Gudrun, Karin, Klara and one local variety) and retention of nutrients in the wetland and willow plant survival rate, biomass production and nutrient uptake were evaluated. Good retention of nutrients (e.g. Tot. N 66-86% and Tot. P 30-87%) was achieved throughout the study period. After two growing seasons, the variety Gudrun showed the best survival rate and significantly higher biomass production (5.7 t/ha) than Karin, Klara and the local variety (1.7, 3.0 and 0.02 t/ha, respectively). Thus, willow wetlands are suitable systems for nutrient recovery from pre-treated wastewater in cold climate regions. However, the willow variety used should be chosen carefully, as there can be significant differences in survival rate and biomass production between varieties.


Assuntos
Salix , Áreas Alagadas , Biomassa , Clima Frio , Finlândia , Polônia , Esgotos , Suécia
8.
Environ Sci Technol ; 54(10): 6329-6343, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32343132

RESUMO

As global warming and climate change become perceived as significant, the release of greenhouse gases (GHGs) stored in the earth's polar regions is considered a matter of concern. Here, we focused on exploiting GHGs to address potential global warming challenges in the north polar regions. In particular, we used CO2 as a soft oxidant to recover energy as syngas (CO and H2) and to produce biochars from pyrolysis of peat moss. CO2 expedited homogeneous reaction with volatile matters from peat moss pyrolysis, and the mechanistic CO2 role resulted in the conversion of CO2 and peat moss to CO at ≥530 °C. Steel slag waste was then used as an ex situ catalyst to increase reaction kinetics, addressing the issue of the role of CO2 being limited to ≥530 °C, with the result where substantial H2 and CO formation was achieved at a milder temperature. The porosity of biochars, a solid peat moss pyrolysis product, was modified in the presence of CO2, with a significant improvement in CO2 adsorption capacity compared to those achieved by N2 pyrolysis. Therefore, CO2 has the potential to serve as an initial feedstock in sustainable biomass-to-energy applications and biochar production, mitigating atmospheric carbon concentrations.


Assuntos
Pirólise , Sphagnopsida , Dióxido de Carbono , Carvão Vegetal , Clima Frio , Oxidantes
10.
Artigo em Inglês | MEDLINE | ID: mdl-32178438

RESUMO

Currently, adipose tissue is considered an endocrine organ that produces hormone-active substances, including leptin, which can play a key role in thermoregulation processes. Therefore, we performed a meta-analysis to investigate the influence of the climatic environment on leptin levels. A systematic literature search in the databases was carried out on 10 January 2020. Finally, 22 eligible articles were included in the current meta-analysis and a total of 13,320 participants were covered in the final analysis. It was shown that males of the "North" subgroup demonstrated significantly higher levels of leptin (10.02 ng/mL; CI: 7.92-12.13) than males of the "South" subgroup (4.9 ng/mL; CI: 3.71-6.25) (p = 0.0001). On the contrary, in the female group, a similar pattern was not detected (p = 0.91). Apparently, in order to maintain body temperature, higher leptin levels are required. The results of the study indicate that such effects are most pronounced in males and to a smaller extent in females, apparently due to a relatively high initial concentration of leptin in females. The correlation between leptin levels and climatic environment data support the hypothesis of leptin-mediated thermoregulation as an adaptive mechanism to cold climates.


Assuntos
Aclimatação , Adaptação Fisiológica , Clima Frio , Leptina , Adaptação Fisiológica/fisiologia , Regulação da Temperatura Corporal , Feminino , Humanos , Leptina/metabolismo , Masculino
11.
J Equine Vet Sci ; 85: 102848, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31952637

RESUMO

The objective of this study was to examine changes in surface temperature of blanketed horses during cold weather. Four mature stock-type horses were used in a 4 × 4 Latin square design. Treatments included 3 different blanket weights (based on g of fiberfill): light weight (LW; 0 g), medium weight (MW; 200 g), heavy weight (HW; 400 g), and a nonblanketed control (CON). Thermographic images were obtained from a standardized lumbar location before blanketing and immediately after cold exposure. During cold exposure, horses were outside with ad libitum access to grass hay and water for 1 hour. Mean temperature was -23°C with a wind chill of -32°C. After 1 hour, horses were brought inside (15°C) and lumbar images immediately recorded. A 30-minute equilibration period was allowed between each sampling period. Analysis of variance was computed using the general linear model procedure of SAS with statistical significance declared at P values ≤ 0.05. There was an overall treatment effect (P = .02) for lumbar temperatures after horses were outside for 1 hour with temperatures measuring 22.3°C, 26.8°C, 30.3°C, and 31.5°C for CON, LW, MW, and HW, respectively. Lumbar temperature was warmer (P ≤ .009) for HW and MW compared with CON and tended to be warmer (P = .10) in LW compared with CON. Change in lumbar temperature decreased significantly (P ≤ .01) in CON compared with all other treatments. In conclusion, wearing a blanket can increase lumbar surface temperature during cold weather with the degree of warmth influenced by blanket weight.


Assuntos
Clima Frio , Temperatura Baixa , Animais , Temperatura Corporal , Cavalos , Temperatura , Vento
12.
Environ Pollut ; 256: 113389, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31685327

RESUMO

The boreoatlantic gonate squid (Gonatus fabricii) represents important prey for top predators-such as marine mammals, seabirds and fish-and is also an efficient predator of crustaceans and fish. Gonatus fabricii is the most abundant cephalopod in the northern Atlantic and Arctic Ocean but the trace element accumulation of this ecologically important species is unknown. In this study, trace element concentrations (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, and Zn) were analysed from the mantle muscle and the digestive gland tissue of juveniles, adult females, and adult males that were captured south of Disko Island off West-Greenland. To assess the feeding habitat and trophic position of this species, stable isotopes of carbon (δ13C) and nitrogen (δ15N) were measured in their muscle tissue. Mercury concentrations were positively correlated with size (mantle length) and trophic position. The Hg/Se ratio was assessed because Se has been suggested to play a protective role against Hg toxicity and showed a molar surplus of Se relative to Hg. Cadmium concentrations in the digestive gland were negatively correlated with size and trophic position (δ15N), which suggested a dietary shift from Cd-rich crustaceans towards Cd-poor fish during ontogeny. This study provides trace element concentration data for G. fabricii from Greenlandic waters, which represents baseline data for a northern cephalopod species. Within West-Greenland waters, G. fabricii appears to be an important vector for the transfer of Cd in the Arctic pelagic food web.


Assuntos
Bioacumulação , Decapodiformes/metabolismo , Monitoramento Ambiental/métodos , Metais Pesados/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise , Animais , Regiões Árticas , Oceano Atlântico , Clima Frio , Ecossistema , Feminino , Cadeia Alimentar , Masculino , Metais Pesados/metabolismo , Alimentos Marinhos/análise , Oligoelementos/metabolismo , Poluentes Químicos da Água/metabolismo
13.
Environ Sci Pollut Res Int ; 27(4): 3794-3802, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31879874

RESUMO

Identifying critical source areas (CSAs) of a watershed by phosphorus (P) loss assessment tools is essential for optimal placement of beneficial management practices (BMPs) to address diffuse P pollution. However, lack of significant progress in tackling diffuse P pollution could be, in part, associated with inefficacy of P loss assessment tools for accurately identifying CSAs. Phosphorus loss assessment tools have been developed to simulate P loss from the landscape where runoff is mainly driven by rainfall events. Therefore, they may underperform in cold climates where the land is often frozen during winter and runoff is dominated by snowmelt. This paper (i) reviews the strengths and weaknesses of current P loss assessment tools and their underlying assumptions in simulating soil P dynamics and P transfer to runoff, and (ii) highlights a number of challenges associated with modeling P transfer from agricultural land to surface waters in cold climates. Current P loss assessment tools do not appear to fully represent hydrological and biogeochemical processes responsible for P loss from CSAs, particularly in cold climates. Effort should be made to develop P loss assessment tools that are capable of considering P dynamics through the landscape as a result of abiotic perturbations that are common in cold climates, predicting runoff and P movement over frozen/partially frozen soils, and considering material-P connectivity between landscape and surface waters. Evaluating P loss assessment tools with water quality data is necessary to ensure such modifications result in improved identification of CSAs.


Assuntos
Clima Frio , Fósforo , Agricultura , Fósforo/análise , Fósforo/química , Solo , Qualidade da Água
14.
Artigo em Inglês | MEDLINE | ID: mdl-31698706

RESUMO

The dynamics of many viral infections, including rotaviral infections (RIs), are known to have a complex non-linear, non-stationary structure with strong seasonality indicative of virus and host sensitivity to environmental conditions. However, analytical tools suitable for the identification of seasonal peaks are limited. We introduced a two-step procedure to determine seasonal patterns in RI and examined the relationship between daily rates of rotaviral infection and ambient temperature in cold climates in three Russian cities: Chelyabinsk, Yekaterinburg, and Barnaul from 2005 to 2011. We described the structure of temporal variations using a new class of singular spectral analysis (SSA) models based on the "Caterpillar" algorithm. We then fitted Poisson polyharmonic regression (PPHR) models and examined the relationship between daily RI rates and ambient temperature. In SSA models, RI rates reached their seasonal peaks around 24 February, 5 March, and 12 March (i.e., the 55.17 ± 3.21, 64.17 ± 5.12, and 71.11 ± 7.48 day of the year) in Chelyabinsk, Yekaterinburg, and Barnaul, respectively. Yet, in all three cities, the minimum temperature was observed, on average, to be on 15 January, which translates to a lag between the peak in disease incidence and time of temperature minimum of 38-40 days for Chelyabinsk, 45-49 days in Yekaterinburg, and 56-59 days in Barnaul. The proposed approach takes advantage of an accurate description of the time series data offered by the SSA-model coupled with a straightforward interpretation of the PPHR model. By better tailoring analytical methodology to estimate seasonal features and understand the relationships between infection and environmental conditions, regional and global disease forecasting can be further improved.


Assuntos
Infecções por Rotavirus/epidemiologia , Estações do Ano , Cidades , Clima Frio , Humanos , Federação Russa/epidemiologia
15.
Actas dermo-sifiliogr. (Ed. impr.) ; 110(9): 734-743, nov. 2019. tab
Artigo em Espanhol | IBECS | ID: ibc-185565

RESUMO

Antecedentes El conocimiento de las variaciones de las enfermedades dermatológicas a lo largo del año podría ser útil para la planificación en salud y el manejo de las enfermedades. Sin embargo, existe escasa información acerca de la variación de los diagnósticos dermatológicos en diferentes épocas del año en una muestra nacional representativa. Objetivos: Evaluar si existe variación en los diagnósticos clínicos dermatológicos entre la temporada de frío y calor en España. Material y métodos: Los datos se han obtenido mediante una encuesta anónima realizada a una muestra aleatoria y representativa de dermatólogos españoles estratificados por área. Cada uno de los participantes recogió todos los diagnósticos clínicos durante 6 días de consulta en 2016 (3 en la temporada de frío y 3 en la temporada de calor). Los diagnósticos se codificaron según la CIE-10. Resultados: Con una proporción de respuesta de 62%, se recolectaron 11.223 diagnósticos clínicos. Los grupos diagnóstico CIE-10 que mostraron variaciones entre temporadas fueron: otras neoplasias benignas de la piel (D23), rosácea (L71) y otros trastornos foliculares (L73), los cuales fueron más frecuentes en la temporada de calor, y acné (L70) el cual fue más frecuente en la temporada de frío. Además, describimos las diferencias en la población pediátrica y según el tipo de asistencia pública frente a privada. Algunas de estas diferencias podrían estar relacionadas con diferencias en la población que consulta en las distintas temporadas. Conclusiones: La frecuencia de la mayoría de los diagnósticos clínicos realizados por dermatólogos no sufre variaciones a lo largo del año. Solo algunos de los diagnósticos clínicos muestran variaciones entre la temporada de frío frente a calor. Estas variaciones observadas pueden estar en relación con las propias enfermedades o pueden ser debidas a cambios estacionales en la demanda de consultas dermatológicas


Background: Knowledge of seasonal variation of cutaneous disorder may be useful for heath planning and disease management. To date, however, descriptions of seasonality including all diagnoses in a representative country sample are very scarce. Objectives: To evaluate if clinical dermatologic diagnosis in Spain change in the hot vs. cold periods. Materials and methods: Survey based on a random sample of dermatologists in Spain, stratified by area. Each participant collected data during 6 days of clinical activity in 2016 (3 in the cold period of the year, 3 in the hot period). Clinical diagnoses were coded using ICD-10. Results: With a 62% response proportion, we got data on 10999 clinical diagnoses. ICD-10 diagnostic groups that showed changes were: other benign neoplasms of skin (D23), rosacea (L71) and other follicular disorders (L73), which were more common in the hot period and acne (L70) which was more frequent in the cold period. We describe differences in the paediatric population and in private vs. public practice. Some of these differences might be associated to differences in the population demanding consultations in different periods. Conclusions: The frequency of most clinical diagnosis made by dermatologists does not change over the year. Just a few of the clinical diagnoses made by dermatologists show a variation in hot vs. cold periods. These variations could be due to the diseases themselves or to seasonal changes in the demand for consultation


Assuntos
Humanos , Dermatopatias/diagnóstico , Clima Frio , Calor Extremo , Dermatopatias/epidemiologia , Espanha/epidemiologia , Estações do Ano , Sociedades Médicas/estatística & dados numéricos , Sociedades Médicas/normas , Análise Estatística
16.
Lima; Perú. Ministerio de Salud; 1 ed., 2 reimp; 20191100. 16 p. ilus.
Monografia em Espanhol | LILACS, Index Psicologia - Periódicos técnico-científicos, MINSAPERÚ | ID: biblio-1026351

RESUMO

El rotafolio describe la información sobre las prácticas para prevenir las infecciones respiratorias agudas ante el friaje y heladas, con énfasis en niños y niñas menores de 5 años, mayores de 60 años de edad o personas con enfermedades crónicas


Assuntos
Clima Frio , Medição de Risco , Desastre Meteorológico , Planos e Programas de Educação em Desastres , Exposição Ambiental , Promoção da Saúde
17.
Oecologia ; 191(4): 767-776, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31620874

RESUMO

Telomere dynamics vary fundamentally between endothermic populations and species as a result of differences in life history, yet we know little about these patterns in ectotherms. In ectotherms, the relationships between climate, metabolism and life history suggest that telomere attrition should be higher at relatively high environmental temperatures compared to relatively low environmental temperatures, but these effects may vary between populations due to local adaptation. To address this hypothesis, we sampled reactive oxygen species (ROS) and telomere length of lizards from warm lowland and cool highland populations of a climatically widespread lizard species that we exposed to hot or cold basking treatments. The hot treatment increased relative telomere length compared to the cold treatment independent of climatic origin or ROS levels. Lizards from the cool highland region had lower ROS levels than those from the warm lowland region. Within the highland lizards, ROS increased more in the cold basking treatment than the hot basking treatment. These results are in the opposite direction to those predicted, suggesting that the relationships between temperature, metabolism, ROS and telomere dynamics are not straightforward. Future work incorporating detailed understanding of the thermal reaction norms of these and other linked traits is needed to fully understand these processes.


Assuntos
Lagartos , Telômero , Animais , Clima Frio , Temperatura Baixa , Temperatura
18.
J Environ Qual ; 48(4): 792-802, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31589688

RESUMO

Cold agricultural regions are important sites of global food production. This has contributed to widespread water quality degradation influenced by processes and hydrologic pathways that differ from warm region analogues. In cold regions, snowmelt is often a dominant period of nutrient loss. Freeze-thaw processes contribute to nutrient mobilization. Frozen ground can limit infiltration and interaction with soils, and minimal nutrient uptake during the nongrowing season may govern nutrient export from agricultural catchments. This paper reviews agronomic, biogeochemical, and hydrological characteristics of cold agricultural regions and synthesizes findings of 23 studies that are published in this special section, which provide new insights into nutrient cycling and hydrochemical processes, model developments, and the efficacy of different potentially beneficial management practices (BMPs) across varied cold regions. Growing evidence suggests the need to redefine optimum soil phosphorus levels and input regimes in cold regions to allow achievement of water quality targets while still supporting strong agricultural productivity. Practices should be considered through a regional and site-specific lens, due to potential interactions between climate, hydrology, vegetation, and soils, which influence the efficacy of nutrient, crop, water, and riparian buffer management. This leads to differing suitability of BMPs across varied cold agricultural regions. We propose a systematic approach (""), to achieve water quality objectives in variable and changing climates, which combines nutrient transport process onceptualization, nderstanding BMP functions, redicting effects of variability and change, onsideration of producer input and agronomic and environmental tradeoffs, practice daptation, nowledge mobilization, and valuation of water quality improvement.


Assuntos
Clima Frio , Qualidade da Água , Agricultura , Fósforo , Solo
19.
J Environ Qual ; 48(4): 850-868, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31589697

RESUMO

The use of cover crops and crop residues is a common strategy to mitigate sediment and nutrient losses from land to water. In cold climates, elevated dissolved P losses can occur associated with freeze-thaw of plant materials. Here, we review the impacts of cover crops and crop residues on dissolved P and total P loss in cold climates across ∼41 studies, exploring linkages between water-extractable P (WEP) in plant materials and P loss in surface runoff and subsurface drainage. Water-extractable P concentrations are influenced by plant type and freezing regimes. For example, WEP was greater in brassica cover crops than in non-brassicas, and increased with repeated freeze-thaw cycles. However, total P losses in surface runoff and subsurface drainage from cropped fields under cold climates were much lower than plant WEP, owing to retention of 45 to >99% of released P by soil. In cold climatic regions, cover crops and crop residues generally prevented soil erosion and loss of particle-bound P during nongrowing seasons in erodible landscapes but tended to elevate dissolved P loss in nonerodible soils. Their impact on total P loss was inconsistent across studies and complicated by soil, climate, and management factors. More research is needed to understand interactions between these factors and plant type that influence P loss, and to improve the assessment of crop contributions to P loss in field settings in cold climates. Further, tradeoffs between P loss and the control of sediment loss and N leaching by plants should be acknowledged.


Assuntos
Clima Frio , Fósforo , Agricultura , Produtos Agrícolas , Solo , Movimentos da Água
20.
Lima; Perú. Ministerio de Salud; 3 ed; 20191000. 14 p. ilus.
Monografia em Espanhol | LILACS, MINSAPERÚ | ID: biblio-1026272

RESUMO

El documento contiene prácticas saludables frente a las temporadas de bajas temperaturas para que los gobiernos locales fortalezcan los conocimientos de su comunidad para que desarrollen prácticas saludables frente a esta temporada de bajas temperaturas, de manera que puedan organizar la vigilancia comunal de su población vulnerable y posibilite la reducción del efecto negativo del friaje en la salud de la población.


Assuntos
Infecções Respiratórias , Clima Frio , Medição de Risco , Desastre Meteorológico , Planos e Programas de Educação em Desastres , Exposição Ambiental , Resposta ao Choque Frio , Promoção da Saúde
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