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1.
Environ Monit Assess ; 192(11): 678, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33025274

RESUMO

Detecting the probable impact of climate change responses on hydrological components is most important for understanding such changes on water resources. The impact of climate change on virtual parameters of water was assessed through hydrological modeling of the Wunna, Mahanadi (Middle), and Bharathpuzha watersheds. In this article, future hydrological component responses under two Representative Concentration Pathway (RCP) 4.5 and 8.5 scenarios were considered for investigating the runoff, sediment, and water storage components. RegCM4 CSIRO-Mk3.6.0 CORDEX South Asia of RCM model was used which is specially downscaled for the Asian region by IITM-India. Delta change method was adopted to remove bias correction in RCM data. Hydrological simulation for current and future periods was performed by GIS interfaced Soil Water and Assessment Tool (SWAT) model. The surface runoff of Wunna and Bharathpuzha watersheds and the yield of sediment are expected to increase further under RCP8.5 than RCP4.5 and in contrast to Mahanadi watershed. Both blue water storage (BW) and green water storage (GWS) of Wunna watershed are expected to decline under RCP4.5, and rise under RCP8.5 scenario. Both BW and GWS of Bharathpuzha are expected to increase in the future except in western region under RCP4.5 scenario. BW of Mahanadi is expected to increase in the future. However, GWS will decrease in some of the sub-basins. The model-generated results will be helpful for future water resources planning and development.


Assuntos
Mudança Climática , Hidrologia , Ásia , Monitoramento Ambiental , Índia , Modelos Teóricos
2.
Environ Monit Assess ; 192(11): 679, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33025331

RESUMO

In this study, the impacts of land use/land cover (LULC) and climate change on the streamflow and sediment yield were investigated for the Payaswani River Basin, Western Ghats, India. The LULC was determined using Landsat images, and climate data were procured from five general circulation models for representative concentration pathway (RCP) 4.5 (moderate emission) and 8.5 (high emission). The land change modeler was used to derive the future LULC and its changes from 1988 (historical) to 2030 (future) by using the transition matrix method. The SWAT model was used to assess the impacts of LULC and climate change for the streamflow and sediment yield. The results showed that decrease in forests and grasslands and increase in plantation, agricultural, and urban areas from 1988 to 2030 would lead to an increase in the mean streamflow (11.23%) and sediment yield (17.41%). Under RCP 4.5, climate change would decrease the streamflow by 2.38% in 2030. However, under RCP 8.5, climate change would increase the streamflow by 0.12% in 2030. The sediment yield under RCP 4.5 and 8.5 would increase by 1.23% and 3.33%, respectively. In comparison with the baseline condition, by 2030 future changes in the LULC and climate would increase the streamflow by 7.05% and 11.71% under RCP 4.5 and 8.5, respectively. The sediment yield would increase by 7.92% and 27.11% under RCP 4.5 and 8.5, respectively. The streamflow and sediment yield were predicted to increase in the summer and winter but decrease in the monsoon season.


Assuntos
Mudança Climática , Rios , Monitoramento Ambiental , Previsões , Índia
3.
Environ Monit Assess ; 192(11): 691, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33037483

RESUMO

Climate change is responsible for changes in the world's vegetation. This study was aimed to investigate the effect of long-term variations in the air temperature, precipitation, and dust concentration on normalized difference vegetation index (NDVI) variations in the spring, summer, and growing season over arid regions of Iran. The results showed that the precipitation had a positive association with the NDVI in the spring and growing seasons (ß > + 0.28; P < 0.05), while air temperature had a negative relationship with the NDVI changes in these seasons (ß > - 0.34; P = 0.013). Our results also showed a negative relationship between the accumulated dust concentration (ADC) and NDVI in the spring (ß = - 0.23; P = 0.09) and growing seasons (ß = - 0.24; P = 0.003). Spatially, the strongest linkage between NDVI and climatic variables was observed in about two-thirds of the study region. In total, our findings indicate that the use of dust concentration, air temperature, and precipitation helps us to make a more accurate approach for evaluating the impacts of climate change on vegetation variations in the arid environments.


Assuntos
Poeira , Monitoramento Ambiental , Mudança Climática , Irã (Geográfico) , Temperatura
5.
Rev Sci Tech ; 39(2): 481-490, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33046927

RESUMO

Climate change is predicted to change the nature and distribution of global farming systems, and strategies will be needed to adapt and optimise global food-producing systems. If genomic technologies are to be useful in this scenario, there is a need for the careful definition of phenotypes and routine sample collection, as well as large-scale genotyping of animal populations. Genomic tools will greatly enhance the characterisation of available germplasm and exploration of local genetic resources, while faster and cheaper DNA sequencing is leading to an increased understanding of the underlying genetic basis of traits. The use of genomic tools to increase animal resilience, reduce methane emissions from cattle and sheep, improve disease resistance, decrease environmental impact, reduce competition for land and water and, finally, increase production may be the most feasible path for the future of livestock production. In this review, the authors discuss various genomic strategies in the light of climate change, focusing on the selection of resistant/tolerant animals, landscape genomics, metagenomics and gene editing.


Assuntos
Mudança Climática , Genômica , Agricultura , Animais , Bovinos , Genoma , Gado , Ovinos
6.
Rev Sci Tech ; 39(2): 461-470, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33046929

RESUMO

In recent times, there has been an increased focus on animal health and zoonotic diseases that have the potential to trigger epidemics or pandemics that disproportionately affect the poor and most vulnerable. The recent Ebola, Zika and COVID-19 outbreaks demonstrate the devastating human, social and economic impacts of such diseases if they are not prevented or controlled, ideally at source. The risk drivers for zoonoses, which are complex and often interdependent, include climate change and related disasters, antimicrobial resistance, and anthropogenic drivers such as land-use changes and animal production practices. Understanding these drivers requires a better understanding of the ecology of zoonotic diseases at the human-animal-environment interface. Biosecurity and biosafety are critical for reducing the risk of accidental or deliberate release and should be included in risk management strategies. International frameworks for sustainable development, climate change, and disaster risk reduction have all integrated health as one of the core areas of work, calling for better preparedness and response to biological hazards and increased health system resilience. To improve their ability to prevent, prepare for, and respond to emerging and re-emerging threats, countries should address these risk drivers, taking a multidisciplinary One Health approach that involves the animal and human health and environment sectors. Cross-border cooperation is also vital, as diseases know no boundaries.


Assuntos
Infecções por Coronavirus , Desastres , Pandemias , Pneumonia Viral , Infecção por Zika virus , Zika virus , Animais , Betacoronavirus , Mudança Climática , Emergências/veterinária , Humanos , Gestão de Riscos , Infecção por Zika virus/veterinária , Zoonoses/epidemiologia
7.
J Environ Qual ; 49(2): 314-323, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33016430

RESUMO

Soil freeze-thaw cycles (FTCs) profoundly influence biophysical conditions and modify biogeochemical processes across many northern-hemisphere and alpine ecosystems. How FTCs will contribute to global processes in seasonally snow-covered ecosystems in the future is of particular importance as climate change progresses and winter snowpacks decline. Our understanding of these contributions is limited because there has been little consideration of inter- and intrayear variability in the characteristics of FTCs, in part due to a limited appreciation for which of these characteristics matters most with respect to a given biogeochemical process. Here, we introduce the concept of effective FTCs: those that are most likely linked to changes in key soil processes. We also propose a set of parameters to quantify and characterize effective FTCs using standard field soil temperature data. To put these proposed parameters into effective practice, we present FTCQuant, an R package of functions that quantifies FTCs based on a set of user-defined parameter criteria and, importantly, summarizes the individual characteristics of each FTC counted. To demonstrate the utility of these new concepts and tools, we applied the FTCQuant package to re-analyze data from two published studies to help explain over-winter changes to N2 O emissions and wet-aggregate stability. We found that effective FTCs would be defined differently for each of these response variables and that effective FTCs provided a 76 and 33% increase in model fit for wet-aggregate stability and cumulative N2 O emission, respectively, relative to conventional FTC quantification methods focusing on fluctuations around 0 °C. These results demonstrate the importance of identifying effective FTCs when scaling soil processes to regional or global levels. We hope our contributions will inform future deductions, hypothesis generation, and experimentation with respect to expected changes in freeze-thaw cycling globally.


Assuntos
Ecossistema , Solo , Mudança Climática , Congelamento , Neve
9.
Sci Total Environ ; 747: 142084, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33076212

RESUMO

Forest habitats change significantly under the influence of global warming. It is important to predict the effects of these changes, especially in primeval forests which currently represent a small percentage of temperate forests. Such changes often manifest themselves in an acceleration of the frequency of mass seeding of trees, which causes cascading effects in various organisms. We evaluated changes in: tree masts (oak Quercus robur and hornbeam Carpinus betulus), rodent abundance (yellow-necked mouse Apodemus flavicollis), folivorous caterpillar abundance (winter moth Operophtera brumata), and the breeding success of a cavity-nesting songbird (collared flycatcher Ficedula albicollis) in over a 30-year period in the Bialowieza Forest (E Poland). We also analysed temperature, precipitation and snow cover to determine the effects of weather on each trophic level. Previous studies have exposed the indirect effect of tree masting on songbirds breeding in open nests. Our study uniquely highlights the relationships between trees, rodents, caterpillars, and a cavity-nesting bird. Precipitation was positively correlated with the fructification of trees, abundance of caterpillars, and the breeding losses of flycatchers (in July, August, October in the previous year, in May in the current year, respectively). We found that along with the changing climate, the frequency of mast years of oak increased, which caused an increasing frequency of rodent outbreaks. The abundance of mice was positively correlated with the predation on flycatcher broods (current year) and negatively - with the abundance of caterpillars (following year). We predict that current global trends in climate change will have a negative impact on the flycatcher due to the cascading effects from the above species. Bearing in mind that F. albicollis is one of the most numerous bird species, it can be assumed that more frequent masting will result in substantial changes in the entire bird assemblage, and presumably also other groups of animals.


Assuntos
Aves Canoras , Árvores , Animais , Cruzamento , Mudança Climática , Florestas , Camundongos , Polônia
10.
Environ Monit Assess ; 192(11): 707, 2020 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-33068183

RESUMO

Among the problems related to water security, the effects of climate change on water availability stand out. Researchers have used hydrological models integrated with climate models in order to predict the streamflow behaviour in different hydrographic basins. This work aimed to analyse future climate scenarios for the Ribeirão do Lobo River Basin, located in the state of São Paulo, Brazil. The stochastic generator PGECLIMA_R was used in the simulation of climate data, which were used as input data in the hydrological model SMAP, after it was calibrated and validated for the study site. In all, five future scenarios were generated, with scenarios A, B, C and D projected based on the 5th report of the IPCC and scenario E based on the trend of climate data in the region. Among the scenarios generated, scenario D, which considers an increase of 4.8 °C in air temperature and a reduction of 10% in rainfall, is responsible for the worst water condition in the basin and can reduce up to 72.41% of the average flow and up to 55.50%, 54.18% and 38.17% of the low flow parameters Q90%, Q95% and Q7,10, respectively, until the end of the twenty-first century. However, the E scenario also becomes a matter of concern, since it was responsible for greater increases in temperature and greater reductions in rainfall and, consequently, more drastic monthly reductions in streamflow, which may negatively impact water resources and affect the various uses of water in the Ribeirão do Lobo River Basin.


Assuntos
Mudança Climática , Modelos Teóricos , Brasil , Monitoramento Ambiental , Hidrologia
11.
Lakartidningen ; 1172020 10 12.
Artigo em Sueco | MEDLINE | ID: mdl-33051860

RESUMO

The 2030 Agenda for Sustainable Development and its seventeen Sustainable Development Goals were adopted by the United Nations General Assembly in 2015. It is a bold agenda for global social, environmental and economic development, with human health as a central theme. Even though substantial improvements in health have been achieved during the last decades, every year over 5 million children die, mostly from preventable causes, and 300 000 women die in conjunction with childbirth. Premature deaths from non-communicable diseases are increasing, and our ability to treat infections is under threat through widespread anti-microbial resistance. Climate change is recognized as the biggest threat to health in our time. When the world now starts to plan for how society and our health systems should be reorganized after the COVID-19 pandemic the 2030 Agenda could and should play a central role. In this context, Agenda 2030 provides an ambitious roadmap for development, with its emphasis on collaboration across borders and disciplines. The agenda is achievable but reaching its goals will require strong commitment at all levels and societal change on a large scale.


Assuntos
Infecções por Coronavirus , Saúde Global , Pandemias , Pneumonia Viral , Desenvolvimento Sustentável , Betacoronavirus , Criança , Mortalidade da Criança , Mudança Climática , Feminino , Humanos
12.
Environ Monit Assess ; 192(11): 716, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33083864

RESUMO

In this research, sea surface temperature (SST) variability for the summer season in the Aegean Sea was analysed over a period of 30 years by using the Landsat thermal infrared bands. A total of 88 Landsat 5, 7, and 8 thermal infrared satellite images from June, July, and August were used for each year from 1989 to 2019. To estimate SST from the thermal infrared band data, thermal infrared sensor at-sensor spectral radiance, and thermal infrared sensor top-of-atmosphere brightness temperatures were used. SST pixel values were extracted from thermal images for the 3-month summer season of each year. In order to validate the findings, regression analysis was performed between the Mediterranean Sea Ultra High Resolution SST L4 data and Landsat data for the 2008-2019 period. Regression constant R-squared values were found to be 0.9672 for June, 0.9550 for July, 0.9634 for August, and 0.9634 for all summer seasons. It was calculated that the minimum value of the average SST was 18.44 ± 2.87 °C in 1992, and the maximum value of the average SST was 23.45 ± 0.70 °C in 2018. According to the Landsat data, over the past 30 years, the annual average SST changes were estimated to be 0.11 °C, and the total changes of average SST were estimated to be 3.19 ± 1.26 °C. As a result of the analysis and the validation, we can see that there is a rising trend in sea surface temperature in the Aegean Sea. However, it is difficult to determine whether this upward trend is related to global climate change.


Assuntos
Mudança Climática , Monitoramento Ambiental , Mar Mediterrâneo , Estações do Ano , Temperatura
13.
Nat Commun ; 11(1): 4945, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009378

RESUMO

Spring warming substantially advances leaf unfolding and flowering time for perennials. Winter warming, however, decreases chilling accumulation (CA), which increases the heat requirement (HR) and acts to delay spring phenology. Whether or not this negative CA-HR relationship is correctly interpreted in ecosystem models remains unknown. Using leaf unfolding and flowering data for 30 perennials in Europe, here we show that more than half (7 of 12) of current chilling models are invalid since they show a positive CA-HR relationship. The possible reason is that they overlook the effect of freezing temperature on dormancy release. Overestimation of the advance in spring phenology by the end of this century by these invalid chilling models could be as large as 7.6 and 20.0 days under RCPs 4.5 and 8.5, respectively. Our results highlight the need for a better representation of chilling for the correct understanding of spring phenological responses to future climate change.


Assuntos
Mudança Climática , Temperatura Baixa , Folhas de Planta/fisiologia , Estações do Ano , Betula/fisiologia , Temperatura Alta , Modelos Lineares , Modelos Biológicos
14.
Nat Commun ; 11(1): 4943, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009384

RESUMO

Despite their high vulnerability, insular ecosystems have been largely ignored in climate change assessments, and when they are investigated, studies tend to focus on exposure to threats instead of vulnerability. The present study examines climate change vulnerability of islands, focusing on endemic mammals and by 2050 (RCPs 6.0 and 8.5), using trait-based and quantitative-vulnerability frameworks that take into account exposure, sensitivity, and adaptive capacity. Our results suggest that all islands and archipelagos show a certain level of vulnerability to future climate change, that is typically more important in Pacific Ocean ones. Among the drivers of vulnerability to climate change, exposure was rarely the main one and did not explain the pattern of vulnerability. In addition, endemic mammals with long generation lengths and high dietary specializations are predicted to be the most vulnerable to climate change. Our findings highlight the importance of exploring islands vulnerability to identify the highest climate change impacts and to avoid the extinction of unique biodiversity.


Assuntos
Mudança Climática , Ilhas , Mamíferos/fisiologia , Animais , Dieta , Análise de Componente Principal , Especificidade da Espécie
15.
Nature ; 586(7829): 336, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33046881
17.
Nat Commun ; 11(1): 4978, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020475

RESUMO

Tropical forests modify the conditions they depend on through feedbacks at different spatial scales. These feedbacks shape the hysteresis (history-dependence) of tropical forests, thus controlling their resilience to deforestation and response to climate change. Here, we determine the emergent hysteresis from local-scale tipping points and regional-scale forest-rainfall feedbacks across the tropics under the recent climate and a severe climate-change scenario. By integrating remote sensing, a global hydrological model, and detailed atmospheric moisture tracking simulations, we find that forest-rainfall feedback expands the geographic range of possible forest distributions, especially in the Amazon. The Amazon forest could partially recover from complete deforestation, but may lose that resilience later this century. The Congo forest currently lacks resilience, but is predicted to gain it under climate change, whereas forests in Australasia are resilient under both current and future climates. Our results show how tropical forests shape their own distributions and create the climatic conditions that enable them.


Assuntos
Florestas , Clima Tropical , África , Ásia Sudeste , Austrália , Mudança Climática , Conservação dos Recursos Naturais , Ecossistema , Retroalimentação , Chuva , América do Sul
18.
Proc Biol Sci ; 287(1931): 20201140, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-33043866

RESUMO

An improved understanding of life-history responses to current environmental variability is required to predict species-specific responses to anthopogenic climate change. Previous research has suggested that cooperation in social groups may buffer individuals against some of the negative effects of unpredictable climates. We use a 15-year dataset on a cooperative breeding arid zone bird, the southern pied babbler Turdoides bicolor, to test (i) whether environmental conditions and group size correlate with survival of young during three development stages (egg, nestling, fledgling) and (ii) whether group size mitigates the impacts of adverse environmental conditions on survival of young. Exposure to high mean daily maximum temperatures (mean Tmax) during early development was associated with reduced survival probabilities of young in all three development stages. No young survived when mean Tmax > 38°C, across all group sizes. Low survival of young at high temperatures has broad implications for recruitment and population persistence in avian communities given the rapid pace of advancing climate change. Impacts of high temperatures on survival of young were not moderated by group size, suggesting that the availability of more helpers in a group is unlikely to buffer against compromised offspring survival as average and maximum temperatures increase with rapid anthropogenic climate change.


Assuntos
Mudança Climática , Temperatura Alta , Passeriformes , Animais , Aves , Cruzamento
19.
Environ Monit Assess ; 192(10): 632, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32902796

RESUMO

This study assessed the climate change in Pauri district, Uttarakhand, India, a region highly vulnerable to climate change with potentially high loss of livelihoods and lives. The scale of change in the district's climate was analyzed using meteorological station data (1901-2000) and grid data (1985-2015). Perceptions of climate change among forest-dependent communities in three altitude zones (< 1200 m asl (zone A); 1200-1800 m asl (zone B), and > 1800 m asl (zone C)) in the study region were surveyed with respect to 14 climate-specific indicators. Annual mean, maximum, and minimum temperature of seasonal data indicated increasing trends except monsoon. Percentage cloud cover showed an increase, of approximately 3%, while diurnal temperature displayed decreasing trends. Rainfall in the district showed a decreasing trend, with more than 50% of years 1985-2015 receiving less rainfall than the annual average. More than 90% of respondents in zones A and B, and around 65-70% respondents in zone C, reported changes in climate parameters. These findings confirm the long-term observable changes in climate in the region and demonstrate the utility of station data, grid data, and surveys of local communities' perceptions when analyzing climate change. The analysis provided important clues about the nature of climate changes in the district. The results can be used to reduce the gap between bottom-up understanding and top-down policies and to formulate precautionary and ongoing site-specific adaptation practices for communities in different altitude zones in the study region, leading to effective and efficient mitigation of climate change impacts.


Assuntos
Mudança Climática , Meteorologia , Monitoramento Ambiental , Florestas , Índia
20.
Mar Environ Res ; 160: 105025, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32907735

RESUMO

Disturbance is a key factor in most natural environments and, globally, disturbance regimes are changing, driven by increased anthropogenic influences, including climate change. There is, however, still a lack of understanding about how disturbance interacts with species dispersal capacity to shape marine assemblage structure. We examined the impact of ice scour disturbance history (2009-2016) on the nearshore seafloor in a highly disturbed region of the Western Antarctic Peninsula by contrasting the response of two groups with different dispersal capacities: one consisting of high-dispersal species (mobile with pelagic larvae) and one of low-dispersal species (sessile with benthic larvae). Piecewise Structural Equation Models were constructed to test multi-factorial predictions of the underlying mechanisms, based on hypothesised responses to disturbance for the two groups. At least two or three disturbance factors, acting at different spatial scales, drove assemblage composition. A comparison between both high- and low-dispersal models demonstrated that these mechanisms are dispersal dependent. Disturbance should not be treated as a single metric, but should incorporate remote and direct disturbance events with consideration of taxa-dispersal and disturbance legacy. These modelling approaches can provide insights into how disturbance shapes assemblages in other disturbance regimes, such as fire-prone forests and trawl fisheries.


Assuntos
Mudança Climática , Meio Ambiente , Larva , Animais , Regiões Antárticas , Oceanos e Mares , Movimentos da Água
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