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1.
Lancet ; 395(10227): 839, 2020 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-32171392
2.
J Environ Manage ; 261: 109958, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148253

RESUMEN

Small reservoirs, as the preferred blue-green engineering infrastructure for use against intensive runoff processes, have risen in number in Central Europe during the past three decades. However, the modelling of sediment siltation is not included in reservoir planning. The unknown temporal sedimentation of a reservoir can lead to the lifespan of the construction being uncertain. The aim of this study is to present a relatively simple process for local managers to model siltation and, consequently, accurately estimate the lifetime of a small reservoir. Three empirical models (USLE, RUSLE and USPED) were applied to two small catchments in Central Europe. This paper takes advantage of real measured and modelled sedimentation during 2012 and 2017, presenting two different terrain measurement approaches. Our study emphasizes the importance of the R-factor value. The temporal development of the R-factor is dependent on climate change, and the R-factor value has been rising steadily during the last decades. The annual mean R-factor has increased 1.04-times due to changes in precipitation patterns between the periods 1961-1980 and 1997-2016. These changes can explain possible growth in the levels of incoming sediment into reservoirs. We identified the correlation (R > 0.7) between observed sedimentation, the R-factor, and precipitation, and we concluded that the supposed rise of precipitation in Central Europe due to climate change will lead to an increase in the levels of stored sediment in reservoirs. Therefore, it is recommended for reservoir managers to use USPED model and to include the estimation of modelling of siltation rate into reservoirs' maintenance projects.


Asunto(s)
Sedimentos Geológicos , Suelo , Ciudades , Cambio Climático , Europa (Continente)
3.
J Environ Manage ; 261: 110203, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148273

RESUMEN

Sea-level rise is an inevitable consequence of climate change and threatens coastal ecosystems, particularly intertidal habitats that are constrained by landward development. Intertidal habitats support significant biodiversity, but also provide natural buffers from climate-threats such as increased storm events. Predicting the effects of climate scenarios on coastal ecosystems is important for understanding both the degree of habitat loss for associated ecological communities and the risk of the loss of coastal buffer zones. We take a novel approach by combining remote sensing with the IUCN Red List of Ecosystem criteria to assess this impact. We quantified the extent of horizontal intertidal rocky shores along ~200 km of coastline in Eastern Australia using GIS and remote-sensing (LiDAR) and used this information to predict changes in extent under four different climate change driven sea-level rise scenarios. We then applied the IUCN Red List of Ecosystems Criterion C2 (habitat degradation over the next 50 years based on change in an abiotic variable) to estimate the status of this ecosystem using the Hawkesbury Shelf Marine Bioregion as a test coastline. We also used four individual rocky shores as case studies to investigate the role of local topography in determining the severity of sea-level rise impacts. We found that, if the habitat loss within the study area is representative of the entire bioregion, the IUCN status of this ecosystem is 'near threatened', assuming that an assessment of the other criteria would return lower categories of risk. There was, however, high spatial variability in this effect. Rocky shores with gentle slopes had the highest projected losses of area whereas rocky shores expanding above the current intertidal range were less affected. Among the sites surveyed in detail, the ecosystem status ranged from 'least concern' to 'vulnerable', but reached 'endangered' under upper estimates of the most severe scenario. Our results have important implications for conservation management, highlighting a new link between remote sensing and the IUCN Red List of Ecosystem criteria that can be applied worldwide to assess ecosystem risk to sea-level rise.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Australia , Cambio Climático , Tecnología de Sensores Remotos
4.
J Environ Manage ; 261: 110249, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148315

RESUMEN

Understanding the effects of thinning on forest productivity under climate change is vital to adaptive forest management. In the present study, the 3-PGmix model was applied to simulate the thinning effects on productivity of Larix olgensis plantations under climate change using 164 sample plots collected from the 6th, 7th and 8th National Forest Inventories in Jilin Province, northeast China. Climate scenarios of RCP 4.5 and RCP 8.5 were adopted from 2011 to 2100 with corresponding reference years (1981-2010). We simulated four cutting intensities: no-thinning, NT; low intensity thinning with 10% stem removal, LT; moderate thinning with 20% stem removal, MT and heavy thinning with 30% stem removal, HT for three times with 5- and 10-year thinning intervals. The results indicated that the mean net primary productivity (NPP) during the simulated 90 years was increased under RCP 4.5 and RCP 8.5. The LT and MT had positive but HT had negative effects on the mean NPP for the same climate scenario. Increased thinning intensity facilitated the positive effects of climate change on NPP but without a significant interaction effect. During the simulation, LT had the highest NPP value and HT had the biggest NPP increase under future climate change. We also discussed the management of larch plantations under climate change and advocated low intensity thinning with 10-year thinning interval to gain maximum NPP for mitigating climate change.


Asunto(s)
Larix , China , Cambio Climático , Ecosistema , Bosques
5.
An Acad Bras Cienc ; 92(suppl 1): e20180425, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32159584

RESUMEN

The aim of the present study was to assess the effect of Eucalyptus trees in a silvopastoral system on the microclimate and the capacity of that to mitigate the effects of climate change on pasturelands. This study included an open pasture of Piatã palisadegrass and an adjacent pasture that contained both palisadegrass and East-to-West rows of Eucalyptus trees, with 15 m between rows, 2 m between trees within rows. The micrometeorological measurements were collected at several distances from the tree rows and in the open pasture. The silvopastoral system was associated with greater between-row shading when solar declination was high and greater near-tree shading when solar declination was around -22°. Both soil heat flux and temperature were influenced by solar radiation, wind speed, and the ability of tree canopies to reduce radiation losses. Wind speed was consistently lower in the silvopastoral system, owing to the windbreak effect of the Eucalyptus trees. The present study demonstrated that silvopastoral systems can be used to attenuate the effects of climate change, as trees can protect pastureland from intense solar radiation and wind, thereby reducing evapotranspiration and, consequently, improving soil water availability for the understory crop.


Asunto(s)
Cambio Climático , Eucalyptus , Agricultura Forestal , Pradera , Brasil , Eucalyptus/crecimiento & desarrollo , Humedad , Microclima , Estaciones del Año , Suelo , Luz Solar , Viento
6.
Environ Monit Assess ; 192(4): 236, 2020 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-32172340

RESUMEN

Agriculture and forestry are the two major land use classes providing sustenance to the human population. With the pace of development, these two land use classes continue to change over time. Land use change is a dynamic process under the influence of multiple drivers including climate change. Therefore, tracing the trajectory of the changes is challenging. The artificial neural network (ANN) has successfully been applied for tracing such a dynamic process to capture nonlinear responses. We test the application of the multilayer perceptron neural network (MLP-NN) to project the future Agriculture, Forestry and Other Land Use (AFOLU) for the year 2050 for the South Asian Association for Regional Cooperation (SAARC) nations which is a geopolitical union of Afghanistan, Bangladesh, Bhutan, India, Nepal, Maldives, Pakistan and Sri Lanka. The Intergovernmental Panel on Climate Change (IPCC) and Food and Agriculture Organization (FAO) use much frequently the term 'AFOLU' in their policy documents. Hence, we restricted our land use classification scheme as AFOLU for assessing the influence of climate change scenarios of the IPCC fifth assessment report (RCP 2.6, RCP 4.5, RCP 6.0 and RCP 8.5). Agricultural land would increase in all the SAARC nations, with the highest increase in Pakistan and Maldives; moderate increase in Afghanistan, India and Nepal; and the least increase in Bangladesh, Bhutan and Sri Lanka. The forestry land use will witness a decreasing trend under all scenarios in all of the SAARC nations with varying levels of changes. The study is expected to assist planners and policymakers to develop nations' specific strategy to proportionate land use classes to meet various needs on a sustainable basis.


Asunto(s)
Cambio Climático , Agricultura Forestal , Modelos Teóricos , Afganistán , Agricultura , Bangladesh , Bután , Monitoreo del Ambiente , Humanos , India , Islas del Oceano Índico , Nepal , Pakistán , Sri Lanka
7.
Buenos Aires; OPS; 2020-03-02. (OPS/ARG/20-0001).
en Español | PAHO-IRIS | ID: phr2-51904

RESUMEN

[Introducción]. Durante el año, el país obtuvo importantes logros en los avances hacia la Salud Universal, basada en una estrategia de atención primaria. Son significativos los pasos dados para fortalecer capacidades en el primer nivel de atención para personas mayores, así como para personas afectados por hipertensión, el uso problemático de sustancias psicoactivas y trastornos mentales. Hubo un impulso importante en la iniciativa para eliminar la transmisión de madre a hijo de VIH, sífilis, Chagas y hepatitis B, y avances transformativos y modernizados en el sistema de información sanitaria para poder medir el acceso a los servicios de salud y su calidad. La certificación de la eliminación de la malaria otorgada por la OMS constituye un hito para Argentina en salud pública. Asimismo, la evaluación externa al país en la aplicación del Reglamento Sanitario Internacional significa un avance importante y un ejemplo para otros países de la región. El Diagnóstico de la Situación sobre Clima y Salud en la Argentina y el desarrollo de un capítulo de salud en el Plan Nacional de Adaptación al Cambio Climático representan otros logros para manejar riesgos alineados con estándares internacionales. Además, Argentina cooperó con el Caribe para fortalecer capacidades en la lucha contra la resistencia antimicrobiana. Los progresos también son significativos en el análisis sobre el gasto de Argentina en salud y en agua y saneamiento, utilizando instrumentos internacionales que ayudan a transparentar estos desembolsos y mejorar en eficiencia e impacto. Otro logro inédito fue el desarrollo y consenso alcanzado para una Agenda Nacional de Investigación en Salud, así como la promoción en el ámbito legislativo del sistema de advertencias sanitarias en el frente de los envases de productos alimenticios para la prevención de la obesidad, una epidemia que afecta de manera alarmante al país


Asunto(s)
Enfermedades Desatendidas , Malaria , Enfermedad de Chagas , Resistencia a los Insecticidas , Transmisión Vertical de Enfermedad Infecciosa , Tuberculosis , Etiquetado de Alimentos , Cambio Climático , Agua Potable , Violencia de Género , Vigilancia de la Salud del Trabajador , Masculinidad , Gastos en Salud , Gestión del Conocimiento para la Investigación en Salud , Reglamento Sanitario Internacional , Argentina
8.
J Environ Manage ; 260: 109978, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32090795

RESUMEN

This is an evidence from a high-income economy in Southeast Asia and a support for scientific planning of the energy sector in ensuring air pollution and climate change mitigation. A comparative analysis of the energy options for electricity generation in the nation was made considering availability, cost and greenhouse gases emission - CO2, N2O and CH4, using a two-stage method comprising multi-objective optimization and TOPSIS. The renewable (RE) and non-renewable energy (NRE) options available were assessed through the lifecycle approach to determine the lifecycle greenhouse gas emission (LCGHG) and levelized cost of energy (LCOE) per MWh of electricity. Considering historical electricity consumption, annual GDP and population growth from 1965, energy consumption for the year 2035 was forecasted using support vector machine regressor in Weka. Future plans in energy diversification pathways were examined through various scenario multi-objective optimizations with a constraint on resource availability and energy target using genetic algorithm in MATLAB. The outputs were ranked using TOPSIS method. Results showed that greenhouse gases emission could be reduced by 10.3 percent compared to business as usual scenario while the energy mix could attain 10 percent renewable energy in the grid at a relatively lower generation cost.


Asunto(s)
Contaminación del Aire , Gases de Efecto Invernadero , Cambio Climático , Electricidad , Efecto Invernadero , Energía Renovable
9.
J Environ Manage ; 260: 110024, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32090800

RESUMEN

This paper presents a novel climate mitigation action index to evaluate various aspects linked to the implementation of Sustainable Energy Action Plans (SEAP), which define the carbon dioxide emission reduction targets and outline the key actions to achieve these at the municipal level. A SEAP Implementation Index (SII) is developed and applied to study climate change mitigation actions implemented by 102 Municipalities belonging to the Metropolitan City of Milan (Italy) in the framework of the Covenant of Mayors (CoM). The SII is composed of six categories and 16 sub-indicators and results in a final score ranging from 1 to 10. The average rating obtained in the case study area is 4.2, and only eleven Municipalities achieved an evaluation higher than 6. The sensitivity analysis shows the index robustness against variations in the applied weight factors. The population engagement and the management of the initiative, neglected by many Municipalities mostly because of a lack of funding and personnel, are identified as the most critical aspects. Despite the massive participation in the CoM, no quantitative analysis of the SEAPs implementation has been proposed until now and this study shows some severe shortcomings in their application.


Asunto(s)
Cambio Climático , Ciudades , Italia
10.
Ecol Lett ; 23(4): 701-710, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32052555

RESUMEN

Satellite data indicate significant advancement in alpine spring phenology over decades of climate warming, but corresponding field evidence is scarce. It is also unknown whether this advancement results from an earlier shift of phenological events, or enhancement of plant growth under unchanged phenological pattern. By analyzing a 35-year dataset of seasonal biomass dynamics of a Tibetan alpine grassland, we show that climate change promoted both earlier phenology and faster growth, without changing annual biomass production. Biomass production increased in spring due to a warming-induced earlier onset of plant growth, but decreased in autumn due mainly to increased water stress. Plants grew faster but the fast-growing period shortened during the mid-growing season. These findings provide the first in situ evidence of long-term changes in growth patterns in alpine grassland plant communities, and suggest that earlier phenology and faster growth will jointly contribute to plant growth in a warming climate.


Asunto(s)
Cambio Climático , Pradera , Biomasa , Ecosistema , Desarrollo de la Planta , Estaciones del Año , Temperatura Ambiental
12.
Science ; 367(6480): 846-848, 2020 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-32079756
13.
Environ Monit Assess ; 192(3): 183, 2020 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-32072310

RESUMEN

The floodplain wetlands in different regional settings vary with time and space in terms of function and geomorphological diversity. In recent decades, these eco-sensitive waterbodies have been exposed to a wide range of anthropogenic threats and climatic changes. Therefore, assessment of these ecological and environmental threats is prerequisite to understand the state of ecosystem and to develop a sustainable management strategy for conservation of wetland biodiversity and fisheries enhancement. This paper discusses the region-specific pattern of trophic state index (TSI) of the 27 floodplain wetlands in West Bengal, India. Carlson TSI and Lamparelli TSI methods were used to determine a better approach based on historical and continuous dataset and to delineate the interrelationship among historical climatic variability for sustainable management of the resources. The study revealed that agro-climatic divisions do not unveil any significant impact on the TSI calculated using Carlson TSI as well as Lamparelli TSI method. The TSI scores for the two methods were significantly different (p < 0.01) for different zones based on wetland habitat types. The TSI scores revealed most of the wetlands to be in mesotrophic state. Principal component analysis (PCA) indicated that TSI scores were having similar pattern of variation with rainfall and water temperature. The present study also conveys fundamental information on ecological status based on the trophic state, which will aid to develop region-specific strategies for sustainable fisheries enhancement.


Asunto(s)
Cambio Climático , Eutrofización , Humedales , Ecosistema , Monitoreo del Ambiente , India
14.
Environ Monit Assess ; 192(3): 198, 2020 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-32107638

RESUMEN

Forests are important carbon pools as they provide pathway to mitigate climate change. Quantification of forest carbon has gained momentum after Paris Agreement in 2015. This information is a prerequisite for REDD+ implementation and carbon trading. Temperate and subtropical mountain systems of Khyber Pakhtunkhwa province host about one third of Pakistan's 4.51 million ha forests. Present study estimated forest carbon stocks in the Khyber Pakhtunkhwa province of Pakistan. The data was collected from 449 sites in different forests across the province using a stratified cluster sampling technique. Total carbon stock in the forests of the province was estimated at 144.71 million tons with an average of 127.66 ± 9.32 t/ha. Aboveground carbon stock was 68.15 million tons accounting for 48% of the total forest carbon stock of the province. Further, belowground biomass and litter accounted for 10% and 1% respectively. The mean aboveground carbon stock was 59.98 ± 4.26 t/ha. The highest aboveground carbon stock was found in dry temperate forests (99.41 t/ha) followed by moist temperate (85.04 t/ha). Overall, temperate forests have aboveground carbon stock of 90.52 t/ha. Temperate and subtropical forests of Pakistan with high carbon densities have ample potential for reducing forest sector emissions. Therefore, forests of Khyber Pakhtunkhwa province having substantial carbon stocks must be conserved for climate change mitigation. Present study provides a framework for carbon stock assessments in other temperate and subtropical regions of the world.


Asunto(s)
Carbono , Cambio Climático , Bosques , Biomasa , Conservación de los Recursos Naturales , Monitoreo del Ambiente , Pakistán , Árboles
15.
BMJ ; 368: m108, 2020 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-32041707

RESUMEN

OBJECTIVE: To assess short term mortality risks and excess mortality associated with exposure to ozone in several cities worldwide. DESIGN: Two stage time series analysis. SETTING: 406 cities in 20 countries, with overlapping periods between 1985 and 2015, collected from the database of Multi-City Multi-Country Collaborative Research Network. POPULATION: Deaths for all causes or for external causes only registered in each city within the study period. MAIN OUTCOME MEASURES: Daily total mortality (all or non-external causes only). RESULTS: A total of 45 165 171 deaths were analysed in the 406 cities. On average, a 10 µg/m3 increase in ozone during the current and previous day was associated with an overall relative risk of mortality of 1.0018 (95% confidence interval 1.0012 to 1.0024). Some heterogeneity was found across countries, with estimates ranging from greater than 1.0020 in the United Kingdom, South Africa, Estonia, and Canada to less than 1.0008 in Mexico and Spain. Short term excess mortality in association with exposure to ozone higher than maximum background levels (70 µg/m3) was 0.26% (95% confidence interval 0.24% to 0.28%), corresponding to 8203 annual excess deaths (95% confidence interval 3525 to 12 840) across the 406 cities studied. The excess remained at 0.20% (0.18% to 0.22%) when restricting to days above the WHO guideline (100 µg/m3), corresponding to 6262 annual excess deaths (1413 to 11 065). Above more lenient thresholds for air quality standards in Europe, America, and China, excess mortality was 0.14%, 0.09%, and 0.05%, respectively. CONCLUSIONS: Results suggest that ozone related mortality could be potentially reduced under stricter air quality standards. These findings have relevance for the implementation of efficient clean air interventions and mitigation strategies designed within national and international climate policies.


Asunto(s)
Contaminación del Aire/efectos adversos , Exposición a Riesgos Ambientales/efectos adversos , Salud Global/estadística & datos numéricos , Mortalidad , Ozono/efectos adversos , Contaminación del Aire/análisis , Ciudades/estadística & datos numéricos , Cambio Climático/mortalidad , Exposición a Riesgos Ambientales/normas , Política Ambiental , Humanos , Cooperación Internacional , Ozono/análisis , Estaciones del Año
16.
Oecologia ; 192(3): 713-722, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32100152

RESUMEN

Population decline and the threat of extinction are realities currently facing many species. Yet, in most cases, the detailed demographic data necessary to identify causes of population decline are unavailable. Using 43 years (1975-2017) of data from a box-nesting population of tree swallows (Tachycineta bicolor), we identified reduced survival of offspring as a probable demographic cause of population decline. Poor fledging success was associated with increased predation and poor weather conditions during early nestling development. Low juvenile survival and subsequent recruitment was linked to poor weather conditions during the post-fledging period and may also be linked to conditions on the wintering grounds. Regional weather conditions during critical stages of breeding (early nestling and post-fledging) have become progressively worse over the 43-year study period. None of the other factors linked to offspring survival have similarly deteriorated. Overall, our results suggest tree swallows should be added to the growing list of species challenged by climate change, and that other species of aerial insect specialists may face similar impacts of climate change.


Asunto(s)
Golondrinas , Animales , Cruzamiento , Cambio Climático , Árboles , Tiempo (Meteorología)
17.
Bioresour Technol ; 304: 123018, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32087547

RESUMEN

Adoption of circular practices within environmental management is gaining worldwide recognition owing to rapid resource depletion and detrimental effects of climate change. The present study therefore attempted to ascertain the linkages between circular economy (CE) and sustainable development (SD) by examining the role of renewable energy (RE) and waste management (WM) sectors in CE combined with policy setup and enabling frameworks boosting the influx of circularity principles in the Indian context. Results revealed that research dedicated towards energy recovery from waste in India lacks integration with SD. Findings also revealed that although India is extremely dedicated towards attainment of the SDGs, penetration of CE principles within administration requires considerable efforts especially since WM regulations for municipal, plastic and e-waste lack alignment with CE principles. Integration of WM and RE policies under an umbrella CE policy would provide further impetus to the attainment of circularity and SD within the Indian economy.


Asunto(s)
Administración de Residuos , Cambio Climático , India , Fenómenos Físicos , Energía Renovable , Residuos Sólidos
18.
J Environ Manage ; 260: 110127, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32090826

RESUMEN

During the period 1998-2017, floods were responsible for 11% of the loss of life and 23% of the economic loss caused by climate-related and geophysical-related disasters worldwide. An integrated and effective definition of flood risk management strategies therefore still requires synthesized and comprehensive knowledge about the driving forces of flood risk. In this study, 278 Portuguese municipalities are analyzed and classified according to flood hazard, exposure, and vulnerability. After evaluating the three components that describe risk, an index of the flood risk is calculated and a cluster analysis is further performed to understand the role of the risk drivers (hazard, exposure, and vulnerability) in each municipality. The proposed approach therefore provides flood risk indexes on a municipal basis, which are built upon different sources of both cell-by-cell data and an aggregation of municipal-level data that has been statistically validated. Municipalities both in the NW part of the country and along the valleys of major rivers demonstrate a significant superimposition of high levels of exposure and hazard, while vulnerability presents a disperse pattern throughout the country. The results obtained using this approach should contribute to the diversification of flood risk management strategies. This is still lacking in the majority of the national-level flood risk governance processes, namely those strategies that focus on the contingency of daily activities and those aiming at a long-term reduction of the exposure, vulnerability, and hazard components that shape flood disasters.


Asunto(s)
Desastres , Inundaciones , Ciudades , Cambio Climático , Ríos
19.
J Environ Manage ; 260: 110148, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32090840

RESUMEN

To tackle climate change, Chinese government has applied an array of mitigating measures to reduce CO2 emissions. During the 11th Five-year Plan, Chinese government set the emission reduction target policy to reduce energy consumption per unit of gross domestic product (GDP) by 20%. This paper attempts to estimate the effect of this emission reduction target policy on industrial performance from complexity perspective. The result shows more complex industrial structure is related to less coal consumption. In general, emission reduction target policy has a negative effect on the probability of branching into new industries and lower the productivity and profitability of a given industry. However, this negative effect is weaker for more complex industries. Only for industries with very high complexity, emission reduction target policy can improve the performance of an industry rather than exerting a negative effect. Our finding not only helps to design a more effective policy to achieve industrial development strategy, but also provides a potential way to achieve economic growth while reduce the emission of greenhouse gases at the same time.


Asunto(s)
Dióxido de Carbono , Gases de Efecto Invernadero , China , Cambio Climático , Desarrollo Económico , Industrias
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