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1.
Eur J Psychotraumatol ; 12(1): 1956746, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34603634

RESUMEN

The human circadian system creates and maintains cellular and systemic rhythmicity essential for the temporal organization of physiological processes promoting homeostasis and environmental adaptation. Sleep disruption and loss of circadian rhythmicity fundamentally affects master homeostasic regulating systems at the crossroads of peripheral and central susceptibility pathways, similar to acute or chronic stress and, thus, may play a central role in the development of stress-related disorders. Direct and indirect human and animal PTSD research accordingly suggests circadian-system-linked sleep, neuroendocrine, immune, metabolic and autonomic dysregulation, linking circadian misalignment to PTSD pathophysiology. Additionally, there is evidence that sleep and circadian disruption may represent a vital pre-existing risk factor in the prediction of PTSD development, while sleep-related symptoms are among the most prominent in trauma-associated disorders. These facts may represent a need for a shift towards a more chronobiological understanding of traumatic sequel and could support better prevention, evaluation and treatment of sleep and circadian disruption as first steps in PTSD management. In this special issue, we highlight and review recent advances from human sleep and chronobiological research that enhances our understanding of the development and maintenance of trauma-related disorders.

2.
J Environ Sci (China) ; 109: 15-25, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34607664

RESUMEN

Emission intensity and climate change control the transport flux and fate of persistent organic pollutants (POPs) in multiple environmental compartments. This study applied a multimedia model (BETR model) to explore alternations in the spatio-temporal trends of concentrations and transport flux of benzopyrene (BaP), phenanthrene (Phe), perfluorooctane sulfonates (PFOS) and polychlorinated biphenyls (PCBs) in the Chaohu watershed, located in the lower reaches of the Yangtze River, China in response to changes in source emissions and climate. The potential historic and future risks of these pollutants also were assessed. The results suggest that current trends in concentrations and transport were similar to that of their emissions between 2005 and 2018. During the next 100 years, temporal trends and spatial patterns were not predicted to change significantly, which is consistent with climate change. Based on sensitivity and correlation analyses, climate change had significant effects on multi-media concentrations and transport fluxes of BaP, Phe, PFOS and PCBs, and rainfall intensity was the predominant controlling factor. Risk quotients (RQs) of BaP and Phe-in soil increased from 0.42 to 0.95 and 0.06 to 0.35, respectively, from 2005 to 2090, indicating potential risks. The RQs of the other examined contaminants exhibited little potential risk in soil, water, or sediment. Based on spatial patterns, it was inferred that the ecosystem around Lake Chaohu is the most at risk. The study provides insights needed for local pollution control of POPs in the Chaohu watershed. In addition, the developed approach can be applied to other watersheds world-wide.


Asunto(s)
Cambio Climático , Contaminantes Químicos del Agua , China , Ecosistema , Monitoreo del Ambiente , Multimedia , Contaminantes Orgánicos Persistentes , Contaminantes Químicos del Agua/análisis
3.
Environ Monit Assess ; 193(11): 721, 2021 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-34648091

RESUMEN

Past studies indicate that increasing temperatures would accelerate the Earth's water cycle and in turn would increase the evaporation rate. Increased evaporation will result in more frequent and intense storms; hence, most researchers focus on climate change and its effect on Earth, particularly the precipitation. In the last two decades, the Udaipur district, India, faces water scarcity and flooding situations twice. The present study focuses on the prediction of rainfall using the most advanced soft computing techniques (SCT) such as multivariate adaptive regression splines (MARS), classification and regression trees (CART), and gene expression programming (GEP) in India's Udaipur district. The performance of these SCT was evaluated to test the capability to predict the rainfall. Results showed that the MARS model for rainfall prediction showed better performance than the GEP model.


Asunto(s)
Monitoreo del Ambiente , Inundaciones , Cambio Climático , India
4.
Environ Monit Assess ; 193(10): 649, 2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34523031

RESUMEN

The present study aims to assess the recent changes and trends in the extreme climate indices in the Kashmir basin using the observational records from 1980 to 2016. The extreme climate indices were computed using the ClimPACT2 software and a total of 39 indices were selected for the analysis having particular utility to various sectors like agriculture, water resources, energy consumption, and human health. Besides adopting the station scale analysis, regional averages were computed for each index. In terms of the mean climatology, an increase has been observed in the annual mean temperature with a magnitude of 0.024 °C/year. Further, differential warming patterns have been observed in the mean maximum and minimum temperatures with mean maximum temperature revealing higher increases than mean minimum temperature. On the other hand, the annual precipitation shows a decrease over most of the region, and the decreases are more pronouncing in the higher altitudes. The trend analysis of the extreme indices reveals that in consonance with the rising temperature there has been an increase in the warm temperatures and decrease in the cold temperatures across the Kashmir basin. Furthermore, our analysis suggests a decrease in the extreme precipitation events. The drought indices viz., Standardised Precipitation Index (SPI), and Standardised Precipitation Evapotranspiration Index (SPEI) manifest decreasing trends with the tendency towards drier regimes implying the need for better water resource management in the region under changing climate.


Asunto(s)
Cambio Climático , Monitoreo del Ambiente , Sequías , Humanos , Meteorología , Temperatura
5.
BMC Public Health ; 21(1): 1631, 2021 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-34488695

RESUMEN

BACKGROUND: Hot weather leads to increased illness and deaths. The Heatwave Plan for England (HWP) aims to protect the population by raising awareness of the dangers of hot weather, especially for those most vulnerable. Individuals at increased risk to the effects of heat include older adults, particularly 75+, and those with specific chronic conditions, such as diabetes, respiratory and heart conditions. The HWP recommends specific protective actions which relate to five heat-health alert levels (levels 0-4). This study examines the attitudes to hot weather of adults in England, and the protective measures taken during a heatwave. METHODS: As part of a wider evaluation of the implementation and effects of the HWP, a survey (n = 3153) and focus groups, a form of group interview facilitated by a researcher, were carried out after the June 2017 level 3 heat-health alert. Survey respondents were categorised into three groups based on their age and health status: 'vulnerable' (aged 75+), 'potentially vulnerable' (aged 18-74 in poor health) and 'not vulnerable' (rest of the adult population) to hot weather. Multivariable logistic regression models identified factors associated with these groups taking protective measures. In-person group discussion, focused on heat-health, were carried out with 25 people, mostly aged 75 + . RESULTS: Most vulnerable and potentially vulnerable adults do not consider themselves at risk of hot weather and are unaware of the effectiveness of important protective behaviours. Only one-quarter of (potentially) vulnerable adults reported changing their behaviour as a result of hearing hot weather-related health advice during the level 3 alert period. Focus group findings showed many vulnerable adults were more concerned about the effects of the sun's ultra-violet radiation on the skin than on the effects of hot temperatures on health. CONCLUSIONS: Current public health messages appear to be insufficient, given the low level of (potentially) vulnerable adults changing their behaviour during hot weather. In the context of increasingly warmer summers in England due to climate change, public health messaging needs to convince (potentially) vulnerable adults of all the risks of hot weather (not just effects of sunlight on the skin) and of the importance of heat protective measures.


Asunto(s)
Cambio Climático , Calor , Anciano , Actitud , Inglaterra/epidemiología , Humanos , Estaciones del Año , Tiempo (Meteorología)
6.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 33(4): 359-364, 2021 Aug 30.
Artículo en Chino | MEDLINE | ID: mdl-34505442

RESUMEN

OBJECTIVE: To evaluate the impact of environmental and climatic factors on the distribution of suitable habitats of Haemaphysalis longicornis, and to predict the potential distribution of H. longicornis under different climate patterns in China. METHODS: Data pertaining to the distribution of H. longicornis were retrieved from public literatures. The effects of 19 climatic factors (annual mean temperature, annual mean temperature difference between day and night, isothermality, standard deviation of seasonal variation of temperature, maximum temperature of the warmest month, minimum temperature of the coldest month, temperature annual range, mean temperature of the wettest season, mean temperature of the driest season, mean temperature of the warmest season, mean temperature of the coldest season, annual mean precipitation, precipitation of the wettest month, precipitation of the driest month, coefficient of variance of precipitation, precipitation of the wettest season, precipitation of the driest season, precipitation of the warmest season and precipitation of the coldest season) and 4 environmental factors (elevation, slope, slope aspect and vegetation coverage) on the potential distribution of H. longicornis were assessed using the maximum entropy (MaxEnt) model based on the H. longicornis distribution data and climatic and environmental data, and the potential distribution of H. longicornis was predicted under the RCP 2.6 and 8.5 emissions scenarios. RESULTS: Among the environmental and climatic factors affecting the geographical distribution of H. longicornis in China, the factors contributing more than 10% to the distribution of H. longicornis mainly included the precipitation of the driest month (26.0%), annual mean temperature (11.2%), annual mean precipitation (10.0%) and elevation (24.2%). Under the current climate pattern, the high-, medium- and low-suitable habitats of H. longicornis are 1 231 900, 1 696 200 km2 and 1 854 400 km2 in China, respectively. The distribution of H. longicornis increased by 336 100 km2 and 367 300 km2 in 2050 and 2070 under the RCP 2.6 emissions scenario, and increased by 381 000 km2 and 358 000 km2 in 2050 and 2070 under the RCP 8.5 emissions scenario in China, respectively. CONCLUSIONS: Climatic and environmental factors, such as precipitation, temperature and elevation, greatly affect the distribution of H. longicornis in China, and the suitable habitats of H. longicornis may expand in China under different climate patterns in future.


Asunto(s)
Cambio Climático , Ecosistema , China , Clima , Predicción , Temperatura
7.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 33(4): 365-372, 2021 Aug 19.
Artículo en Chino | MEDLINE | ID: mdl-34505443

RESUMEN

OBJECTIVE: To investigate the current distribution of ticks and predict the suitable habitats of ticks in the Yangtze River Delta urban agglomeration in 2017, so as to provide insights into tick control and management of tick-borne diseases in these areas. METHODS: All publications pertaining to tick and pathogen distribution in the Yangtze River Delta urban agglomeration were retrieved, and the geographical location of tick distribution was extracted. The effects of 19 climatic factors on the distribution of ticks were examined using the jackknife method, including the mean temperature of the wettest quarter, precipitation of the coldest quarter, mean temperature of the driest quarter, maximum temperature of the warmest month, precipitation of the driest month, minimal temperature of the coldest month, annual precipitation, mean daily temperature range, precipitation seasonality, annual temperature range, temperature seasonality, annual mean temperature, mean temperature of the warmest quarter, precipitation of the wettest quarter, isothermality, mean temperature of the coldest quarter, precipitation of the wettest month, precipitation of the driest quarter and precipitation of the warmest quarter. The distribution of ticks was analyzed in 2020 using the maximum entropy (MaxEnt) model, and the potential suitable habitats of ticks were predicted in 2070 using the MaxEnt model based on climatic data. RESULTS: A total of 380 Chinese and English literatures were retrieved, and 148 tick distribution sites were extracted, with 135 sites included in the subsequent analysis. There were 7 genera (Haemaphysalis, Rhipicephalus, Ixodes, Dermacentor, Boophilus, Hyalomma and Amblyomma) and 27 species of ticks detected in the Yangtze River Delta urban agglomeration. The climatic factors affecting the distribution of ticks in the Yangtze River Delta urban agglomeration mainly included the mean temperature of the wettest quarter and the precipitation of the coldest quarter, with 26.1% and 23.6% contributions to tick distributions. The high-, medium- and low-suitable habitats of ticks were 20 337.08, 40 017.38 km2 and 74 931.43 km2 in the Yangtze River Delta urban agglomeration in 2020, respectively. The climate changes led to south expansion of the suitable habitats of ticks in the Yangtze River Delta urban agglomeration in 2070, and the total areas of suitable habitats of ticks was predicted to increase by 18 100 km2. In addition, the high-, medium- and low-suitable habitats of ticks were predicted to increase to 24 317.84, 45 283.02 km2 and 83 766.38 km2 in the Yangtze River Delta urban agglomeration in 2070, respectively. CONCLUSIONS: Multiple tick species are widespread in the Yangtze River Delta urban agglomeration, and the future climate changes may lead to expansion of tick distribution in these areas.


Asunto(s)
Ixodes , Ríos , Animales , Cambio Climático , Ecosistema , Temperatura
8.
Nature ; 597(7876): 366-369, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34526704

RESUMEN

Southeast Australia experienced intensive and geographically extensive wildfires during the 2019-2020 summer season1,2. The fires released substantial amounts of carbon dioxide into the atmosphere3. However, existing emission estimates based on fire inventories are uncertain4, and vary by up to a factor of four for this event. Here we constrain emission estimates with the help of satellite observations of carbon monoxide5, an analytical Bayesian inversion6 and observed ratios between emitted carbon dioxide and carbon monoxide7. We estimate emissions of carbon dioxide to be 715 teragrams (range 517-867) from November 2019 to January 2020. This is more than twice the estimate derived by five different fire inventories8-12, and broadly consistent with estimates based on a bottom-up bootstrap analysis of this fire episode13. Although fires occur regularly in the savannas in northern Australia, the recent episodes were extremely large in scale and intensity, burning unusually large areas of eucalyptus forest in the southeast13. The fires were driven partly by climate change14,15, making better-constrained emission estimates particularly important. This is because the build-up of atmospheric carbon dioxide may become increasingly dependent on fire-driven climate-carbon feedbacks, as highlighted by this event16.


Asunto(s)
Dióxido de Carbono/análisis , Imágenes Satelitales , Incendios Forestales/estadística & datos numéricos , Atmósfera/química , Australia , Teorema de Bayes , Monóxido de Carbono/análisis , Cambio Climático , Eucalyptus , Bosques , Pradera , Incertidumbre
9.
Horm Metab Res ; 53(9): 575-587, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34496408

RESUMEN

Global warming and the rising prevalence of obesity are well described challenges of current mankind. Most recently, the COVID-19 pandemic arose as a new challenge. We here attempt to delineate their relationship with each other from our perspective. Global greenhouse gas emissions from the burning of fossil fuels have exponentially increased since 1950. The main contributors to such greenhouse gas emissions are manufacturing and construction, transport, residential, commercial, agriculture, and land use change and forestry, combined with an increasing global population growth from 1 billion in 1800 to 7.8 billion in 2020 along with rising obesity rates since the 1980s. The current Covid-19 pandemic has caused some decline in greenhouse gas emissions by limiting mobility globally via repetitive lockdowns. Following multiple lockdowns, there was further increase in obesity in wealthier populations, malnutrition from hunger in poor populations and death from severe infection with Covid-19 and its virus variants. There is a bidirectional relationship between adiposity and global warming. With rising atmospheric air temperatures, people typically will have less adaptive thermogenesis and become less physically active, while they are producing a higher carbon footprint. To reduce obesity rates, one should be willing to learn more about the environmental impact, how to minimize consumption of energy generating carbon dioxide and other greenhouse gas emissions, and to reduce food waste. Diets lower in meat such as a Mediterranean diet, have been estimated to reduce greenhouse gas emissions by 72%, land use by 58%, and energy consumption by 52%.


Asunto(s)
Cambio Climático , Obesidad/etiología , Agricultura/economía , Agricultura/tendencias , COVID-19/complicaciones , COVID-19/epidemiología , COVID-19/patología , Cambio Climático/historia , Comorbilidad , Disruptores Endocrinos/toxicidad , Ambiente , Exposición a Riesgos Ambientales/historia , Exposición a Riesgos Ambientales/estadística & datos numéricos , Gases de Efecto Invernadero/toxicidad , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Obesidad/epidemiología , Obesidad/metabolismo , Pandemias , Factores de Riesgo
10.
Environ Monit Assess ; 193(10): 654, 2021 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-34529161

RESUMEN

The Himalaya, by virtue of its location and stupendous height, acts as a great climatic divide and regulates meteorological conditions in the subcontinent regions of South Asia. However, the associated complexities and their effects are yet to be resolved to understand the meteorology of the Indian Himalayan Region (IHR). In this review volume, we synthesize the results and inferences of several studies carried out in the IHR using in situ data, remotely sensed data, and model-based meteorological observations. Results provide insights into climate change, scientific gaps, and their causes in deciphering meteorological observations from the last century to recent decades and envisage impacts of climate change on water reservoirs in the future. Warming trend of air temperature, in contrast to global temperature, has been projected in recent decades (after 1990) with a greater warming rate in the maximum temperature than the minimum temperature. This drifting of air temperature from the beginning of last century accelerates the diurnal temperature range of the Himalayas. An elevation-dependent warming trend is mostly perceived in the northwest Himalayan region, implicating an increased warming rate in the Greater Himalaya as compared to the lower and Karakoram Himalaya. No definite trends of precipitation have been observed over different regions of the IHR, suggesting heterogeneous cryosphere-climate interaction between western and central Himalaya. In this review, we have tried to emphasize to the scientific community and policy-makers for enhancing the knowledge of physical and dynamical processes associated with meteorological parameters in the Himalayan terrain.


Asunto(s)
Altitud , Meteorología , Cambio Climático , Monitoreo del Ambiente , Temperatura
11.
Rev Sci Tech ; 40(2): 431-438, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34542104

RESUMEN

Climate change due to increasing greenhouse gas (GHG) emissions is one of the most pressing issues facing society on a global scale. The growth of GHG emissions between 2000 and 2010 was higher than in each of the previous three decades, and each of the past four decades has been successively warmer than any preceding decades since 1850. Continued GHG emissions will cause further warming and changes in the climate system. Climate change affects livestock production in multiple ways, both directly and indirectly. Many of the impacts on the livestock sector result from increasing frequency and magnitude of weather and climate extremes such as droughts, flash floods, untimely rains, frost, hail and severe storms. This article describes some of the most vulnerable disaster communities in Asia, Africa, Australia, Europe and South America. It then describes the importance of meteorological information provided by national Meteorological and Hydrological Services to help Veterinary Services support sustainable management of livestock in vulnerable pastoral communities.


Asunto(s)
Desastres , Gases de Efecto Invernadero , Animales , Cambio Climático , Sequías , Efecto Invernadero , Ganado
12.
Rev Sci Tech ; 40(2): 421-430, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34542106

RESUMEN

Climate change due to increasing greenhouse gas (GHG) emissions is one of the most pressing issues facing society on a global scale. The growth of GHG emissions between 2000 and 2010 was higher than in each of the previous three decades, and each of the past four decades has been successively warmer than any preceding decades since 1850. Continued GHG emissions will cause further warming and changes in the climate system. Climate change affects livestock production in multiple ways, both directly and indirectly. Many of the impacts on the livestock sector result from increasing frequency and magnitude of weather and climate extremes such as droughts, flash floods, untimely rains, frost, hail and severe storms. This article describes some of the most vulnerable disaster communities in Asia, Africa, Australia, Europe and South America. It then describes the importance of meteorological information provided by national Meteorological and Hydrological Services to help Veterinary Services support sustainable management of livestock in vulnerable pastoral communities.


Asunto(s)
Desastres , Gases de Efecto Invernadero , Animales , Cambio Climático , Sequías , Efecto Invernadero , Ganado
13.
Nat Commun ; 12(1): 5226, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34471105

RESUMEN

Marine phytoplankton and zooplankton form the basis of the ocean's food-web, yet the impacts of climate change on their biodiversity are poorly understood. Here, we use an ensemble of species distribution models for a total of 336 phytoplankton and 524 zooplankton species to determine their present and future habitat suitability patterns. For the end of this century, under a high emission scenario, we find an overall increase in plankton species richness driven by ocean warming, and a poleward shift of the species' distributions at a median speed of 35 km/decade. Phytoplankton species richness is projected to increase by more than 16% over most regions except for the Arctic Ocean. In contrast, zooplankton richness is projected to slightly decline in the tropics, but to increase strongly in temperate to subpolar latitudes. In these latitudes, nearly 40% of the phytoplankton and zooplankton assemblages are replaced by poleward shifting species. This implies that climate change threatens the contribution of plankton communities to plankton-mediated ecosystem services such as biological carbon sequestration.


Asunto(s)
Biodiversidad , Calentamiento Global , Biología Marina , Plancton/clasificación , Animales , Regiones Árticas , Cambio Climático , Ecosistema , Cadena Alimentaria , Fitoplancton , Temperatura , Zooplancton
16.
Nature ; 597(7876): 360-365, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34526707

RESUMEN

Fish and other aquatic foods (blue foods) present an opportunity for more sustainable diets1,2. Yet comprehensive comparison has been limited due to sparse inclusion of blue foods in environmental impact studies3,4 relative to the vast diversity of production5. Here we provide standardized estimates of greenhouse gas, nitrogen, phosphorus, freshwater and land stressors for species groups covering nearly three quarters of global production. We find that across all blue foods, farmed bivalves and seaweeds generate the lowest stressors. Capture fisheries predominantly generate greenhouse gas emissions, with small pelagic fishes generating lower emissions than all fed aquaculture, but flatfish and crustaceans generating the highest. Among farmed finfish and crustaceans, silver and bighead carps have the lowest greenhouse gas, nitrogen and phosphorus emissions, but highest water use, while farmed salmon and trout use the least land and water. Finally, we model intervention scenarios and find improving feed conversion ratios reduces stressors across all fed groups, increasing fish yield reduces land and water use by up to half, and optimizing gears reduces capture fishery emissions by more than half for some groups. Collectively, our analysis identifies high-performing blue foods, highlights opportunities to improve environmental performance, advances data-poor environmental assessments, and informs sustainable diets.


Asunto(s)
Acuicultura , Ecosistema , Monitoreo del Ambiente , Alimentos Marinos , Desarrollo Sostenible , Animales , Acuicultura/tendencias , Cambio Climático , Dieta , Ecología , Política Ambiental , Explotaciones Pesqueras , Abastecimiento de Alimentos/métodos , Gases de Efecto Invernadero , Humanos , Moluscos , Nitrógeno , Fósforo , Alimentos Marinos/provisión & distribución , Algas Marinas , Desarrollo Sostenible/tendencias
17.
Ambio ; 50(11): 2009-2021, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34559390

RESUMEN

An assessment of the socio-ecological system of the Nature Park "Numto" in West Siberia was carried out based on ecosystem services (ES) mapping, applying a "cascade approach" which was modified according to the specific conditions of low commercial land-use by Indigenous Peoples and adopted with a focus on making it practicable and understandable by decision-makers. The ES values were defined through stakeholder analysis, while the mapping was based on the biophysical traits of the ecosystems and related spatial distribution of ecosystem functions. The mapped ecosystem values differ from the perceived ones. The assessment identified conflicting land uses and groups of stakeholders, including Indigenous Peoples vulnerable to future climate change-induced deficits in access to ES. The ES that are important for climate change mitigation and adaptation are not valued highly by Indigenous Peoples. ES mapping is suggested as an appropriate method for the development of straightforward recommendations for Nature Park management.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Biodiversidad , Cambio Climático , Humanos , Siberia
18.
Ambio ; 50(11): 1991-2008, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34519957

RESUMEN

We present climate-dependent changes in the high-mountain forest ecotone, old-growth forests, alpine phytocenoses, and deglaciated forelands in the Aktru glacial basin (Altai Republic, Russia). A number of independent sources (variations in upper treeline altitude, dendrochronological data, analysis of lacustrine sediments and botanical and geographical studies linked with the dynamics of glacial-dammed lakes in the Chuya and Kurai intermountain depressions) suggest Holocene temperatures reached about 4 °C higher than today. Unlike the European Alps, glaciers in the continental Altai Mountains disappeared before forming again. Also, the upper altitudinal limit of mountain forests during the Holocene was greater than in the European Alps. The high variability of mountain ecosystems in southern Siberia suggests their potential instability in a currently changing climate. However, periglacial successions associated with the strong continental climate and glacier retreat represent an area of increasing biodiversity and plant cover. The historical and current sensitivity of the continental mountains to climate variations which exceeds that of the European Alps requires greater understanding, environmental protection, and increased social responsibility for the consequences of anthropogenic contributions to climate change: the isolated Altai areas contribute little to climate changes, but are greatly affected by them.


Asunto(s)
Biodiversidad , Cambio Climático , Ecosistema , Cubierta de Hielo , Bosques , Federación de Rusia
19.
J Environ Manage ; 300: 113748, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34543962

RESUMEN

Land-use/cover change is the major cause of terrestrial ecosystem degradation. However, its impacts will be exacerbated due to climate change and population growth, driving agricultural expansion because of higher demand of food and lower agricultural yields in some tropical areas. International strategies aimed to mitigate impacts of climate change and land use-cover change are challenging in developing regions. This study aims to evaluate alternatives to minimize the impacts of these threats under socioeconomic trajectories, in one of the biologically richest regions in Guatemala and Mexico. This study is located at the Usumacinta watershed, a transboundary region that shares a common history, with similar biophysical properties and economic constraints which have led to large land use/cover changes. To understand the impacts on deforestation and carbon emissions of different land-management practices, we developed three scenarios (1): business as usual (BAU), (2) a reducing emissions scenario aimed to reduce deforestation and degradation (REDD+), and (3) zero-deforestation from 2030 onwards based on the international commitments. Our results suggest that by 2050, natural land cover might reduce 22.3 and 12.2% of its extent under the BAU and REDD + scenarios, respectively in comparison with 2012. However, the zero-deforestation scenario shows that by 2050, it would be possible to avoid losing 22.4% of the forested watershed (1.7 million ha) and recover 5.9% (0.4 million hectares) of it. In terms of carbon sequestration, REDD + projects can reduce the carbon losses in natural vegetation, but a zero-deforestation policy can double the carbon sequestration produced by REDD + projects only. This study shows that to reduce the pressures on ecosystems, particularly in regions highly marginalized with significant migration, it is necessary to implement transboundary land-management policies that also integrate poverty alleviation strategies.


Asunto(s)
Cambio Climático , Ecosistema , Agricultura , Conservación de los Recursos Naturales , Bosques
20.
Environ Monit Assess ; 193(10): 676, 2021 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-34586508

RESUMEN

We studied the patterns of pre-collapse communities, the small-scale and the large-scale signals of collapses, and the environmental events before the collapses using four paleoecological and one modern data series. We applied and evaluated eight indicators in our analysis: the relative abundance of species, hierarchical cluster analysis, principal component analysis, total abundance, species richness, standard deviation (without a rolling window), first-order autoregression, and the relative abundance of the dominant species. We investigated the signals at the probable collapse triggering unusual environmental events and at the collapse zone boundaries, respectively. We also distinguished between pulse and step environmental events to see what signals the indicators give at these two different types of events. Our results show that first-order autoregression is not a good environmental event indicator, but it can forecast or indicate the collapse zones in climate change. The rest of the indicators are more sensitive to the pulse events than to the step events. Step events during climate change might have an essential role in initiating collapses. These events probably push the communities with low resilience beyond a critical threshold, so it is crucial to detect them. Before collapses, the total abundance and the species richness increase, the relative abundance of the species decreases. The hierarchical cluster analysis and the relative abundance of species together designate the collapse zone boundaries. We suggest that small-scale signals should be involved in analyses because they are often earlier than large-scale signals.


Asunto(s)
Cambio Climático , Monitoreo del Ambiente , Biodiversidad , Ecosistema
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