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1.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 33(4): 359-364, 2021 Aug 30.
Artigo em Chinês | MEDLINE | ID: mdl-34505442

RESUMO

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.


Assuntos
Mudança Climática , Ecossistema , China , Clima , Previsões , Temperatura
2.
Nat Commun ; 12(1): 5102, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34429405

RESUMO

Range shifts of infectious plant disease are expected under climate change. As plant diseases move, emergent abiotic-biotic interactions are predicted to modify their distributions, leading to unexpected changes in disease risk. Evidence of these complex range shifts due to climate change, however, remains largely speculative. Here, we combine a long-term study of the infectious tree disease, white pine blister rust, with a six-year field assessment of drought-disease interactions in the southern Sierra Nevada. We find that climate change between 1996 and 2016 moved the climate optimum of the disease into higher elevations. The nonlinear climate change-disease relationship contributed to an estimated 5.5 (4.4-6.6) percentage points (p.p.) decline in disease prevalence in arid regions and an estimated 6.8 (5.8-7.9) p.p. increase in colder regions. Though climate change likely expanded the suitable area for blister rust by 777.9 (1.0-1392.9) km2 into previously inhospitable regions, the combination of host-pathogen and drought-disease interactions contributed to a substantial decrease (32.79%) in mean disease prevalence between surveys. Specifically, declining alternate host abundance suppressed infection probabilities at high elevations, even as climatic conditions became more suitable. Further, drought-disease interactions varied in strength and direction across an aridity gradient-likely decreasing infection risk at low elevations while simultaneously increasing infection risk at high elevations. These results highlight the critical role of aridity in modifying host-pathogen-drought interactions. Variation in aridity across topographic gradients can strongly mediate plant disease range shifts in response to climate change.


Assuntos
Basidiomycota , Mudança Climática , Doenças das Plantas , Ribes , Clima , Secas , Florestas , Interações Hospedeiro-Patógeno , Doenças das Plantas/microbiologia , Plantas , Prevalência , Água
3.
J Insect Sci ; 21(4)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34369564

RESUMO

The recent introduction of the Asian giant hornet, Vespa mandarinia Smith, in the United States in late 2019 has raised concerns about its establishment in the Pacific Northwest and its potential deleterious effects on honey bees, Apis spp., and their pollination services in the region. Therefore, we conducted a risk assessment of the establishment of V. mandarinia in Washington, Oregon, Montana, and Idaho on a county-by-county basis. Our highly conservative tier-1 qualitative and semiquantitative risk assessment relied on the biological requirements and ecological relationships of V. mandarinia in the environments of the Pacific Northwest. Our risk characterization was based on climate and habitat suitability estimates for V. mandarinia queens to overwinter and colonize nests, density and distribution of apiaries, and locations of major human-mediated introduction pathways that may increase establishment of the hornet in the counties. Our results suggest that 32 counties in the region could be at low risk, 120 at medium risk, and 23 at high risk of establishment. Many of the western counties in the region were estimated to be at the highest risk of establishment mainly because of their suitable climate for queens to overwinter, dense forest biomass for nest colonization, and proximity to major port and freight hubs in the region. By design, our tier-1 risk assessment most likely overestimates the risk of establishment, but considering its negative effects, these counties should be prioritized in ongoing monitoring and eradication efforts of V. mandarinia.


Assuntos
Espécies Introduzidas , Vespas , Animais , Abelhas , Clima , Monitorização de Parâmetros Ecológicos , Ecossistema , Medição de Risco , Estados Unidos , Vespas/fisiologia
4.
Sci Rep ; 11(1): 16852, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34413343

RESUMO

The COVID-19 pandemic caused disruptions of public life and imposed lockdown measures in 2020 resulted in considerable reductions of anthropogenic aerosol emissions. It still remains unclear how the associated short-term changes in atmospheric chemistry influenced weather and climate on regional scales. To understand the underlying physical mechanisms, we conduct ensemble aerosol perturbation experiments with the Community Earth System Model, version 2. In the simulations reduced anthropogenic aerosol emissions in February generate anomalous surface warming and warm-moist air advection which promotes low-level cloud formation over China. Although the simulated response is weak, it is detectable in some areas, in qualitative agreement with the observations. The negative dynamical cloud feedback offsets the effect from reduced cloud condensation nuclei. Additional perturbation experiments with strongly amplified air pollution over China reveal a nonlinear sensitivity of regional atmospheric conditions to chemical/radiative perturbations. COVID-19-related changes in anthropogenic aerosol emissions provide an excellent testbed to elucidate the interaction between air pollution and climate.


Assuntos
COVID-19/epidemiologia , Clima , SARS-CoV-2/fisiologia , Aerossóis , Poluentes Atmosféricos , Atmosfera , COVID-19/transmissão , China , Controle de Doenças Transmissíveis , Extremo Oriente , Humanos , Pandemias , Tempo (Meteorologia)
5.
Environ Int ; 156: 106778, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34425646

RESUMO

Given the important role of green environments playing in healthy cities, the inequality in urban greenspace exposure has aroused growing attentions. However, few comparative studies are available to quantify this phenomenon for cities with different population sizes across a country, especially for those in the developing world. Besides, commonly used inequality measures are always hindered by the conceptual simplification without accounting for human mobility in greenspace exposure assessments. To fill this knowledge gap, we leverage multi-source geospatial big data and a modified assessment framework to evaluate the inequality in urban greenspace exposure for 303 cities in China. Our findings reveal that the majority of Chinese cities are facing high inequality in greenspace exposure, with 207 cities having a Gini index larger than 0.6. Driven by the spatiotemporal variability of human distribution, the magnitude of inequality varies over different times of the day. We also find that exposure inequality is correlated with low greenspace provision with a statistical significance (p-value < 0.05). The inadequate provision may result from various factors, such as dry cold climate and urbanization patterns. Our study provides evidence and insights for central and local governments in China to implement more effective and sustainable greening programs adjusted to different local circumstances and incorporate the public participatory engagement to achieve a real balance between greenspace supply and demand for developing healthy cities.


Assuntos
Parques Recreativos , Urbanização , China , Cidades , Clima , Humanos
6.
Sci Total Environ ; 791: 148407, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34412394

RESUMO

The combined trends of urban heat island (UHI) intensification and global warming led to an increased tendency towards on the greening of cities as a tool for UHI mitigation. Our study examines the range of research approaches and findings regarding the role of green roofs in mitigating urban heat and enhancing human comfort. This review provides an overview of 89 studies conducted in three main climate types (hot-humid, temperate, and dry), from 2000 till 2020. All of the reviewed studies confirm the cooling effect of green roofs and its contribution to reduced heat island intensity regardless of the background climatic condition. However, dry climate has the highest (3 °C) median cooling effect of green roofs among all the climates investigated. Hot-humid climate presents the lowest cooling potential (median = 1 °C) of green roofs among all the climate types. Moreover, green roofs contribute a median surface temperature reduction of 30 °C in hot-humid cities. This value is relatively low for temperate climates (28 °C). Notably, no study has examined the impact of green roofs on surface temperature reduction in dry climates. This review can benefit urban planners and various stakeholders.


Assuntos
Temperatura Baixa , Temperatura Alta , Cidades , Clima , Humanos , Transição de Fase
7.
Sci Total Environ ; 791: 148283, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34412411

RESUMO

Canopy conductance, one of the key variables in simulating evapotranspiration, is strongly influenced by the physiological status of a plant and environmental factors, including photosynthetically active radiation, vapor pressure deficit, air temperature, soil moisture and so on. However, the restrictive functions used to represent these factors rarely consider the dynamics of physiological and environmental factors. This study proposed an improved canopy conductance model by regarding radiation and vapor pressure deficit as the two main influencing factors, quantifying the temporal variation in stomatal responses to radiation that notably adjust stomatal behavior, parameterizing maximum stomatal conductance with plant type-specific functions and proposing a new restrictive function for the VPD. The improved canopy conductance model was incorporated in a surface conductance model for estimating surface conductance and evapotranspiration at 8 flux stations at the Heihe River Basin and the Haihe River Basin. The estimated results were the most accurate when comparing to two other models. Furthermore, the model performance was acceptable when most of the parameters were assumed to be constant across the sites except the reference canopy conductance Gc, ref and the soil evaporation parameter αs, which suggests that the improved canopy conductance model could be used as a parsimony model for improving canopy conductance predictions and water use efficiency over typical climate zones and underlying surface types in North of China.


Assuntos
Transpiração Vegetal , Água , Clima , Rios , Temperatura
8.
Huan Jing Ke Xue ; 42(9): 4140-4150, 2021 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-34414712

RESUMO

This study analyzed the seasonal variation, sources, and source-specific health risks of PM2.5-bound metals in Xinxiang city, Henan province. A total of 112 daily PM2.5 samples were collected over four consecutive seasons during 2019-2020. In total, 19 elements were identified using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The annual concentrations of PM2.5 and 11 heavy metals were calculated to be (66.25±35.73) µg·m-3 and (1.32±0.84) µg·m-3, respectively. Strong seasonal variations were observed in PM2.5 concentrations and the concentrations of associated metal elements, with the lowest concentrations all occurring in summer. The highest concentrations of dust-related elements (e.g., Al, Ca, Fe, Mg,and Ti) were recorded in spring, differing significantly from other elements, which all exhibited the highest mass concentrations in winter. The results apportioned from positive matrix factorization (PMF) and potential source contribution function (PSCF) models showed that the major sources of PM2.5-bound elements were Ni-and Co-related emissions (5.8%), motor vehicles (13.7%), Cd-related emissions(5.1%), combustion emissions (18.2%), and dust (57.3%). Health risk models showed that there were no obvious non-carcinogenic risks associated with these metals, because their hazard quotient (HQ) values were all below 1. Lifetime carcinogenic risks of the five apportioned sources were all higher than the acceptable level (1×10-6). Of these five sources, combustion emissions were the largest contributors to cancer risk (8.74×10-6, 36.9%) and non-cancer risk (0.60, 25.6%). This study suggests that control strategies to mitigate exposure risk in Xinxiang should emphasize reducing the sources of combustion emissions.


Assuntos
Metais Pesados , Material Particulado , Clima , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Material Particulado/efeitos adversos , Material Particulado/análise , Estações do Ano
9.
Braz J Med Biol Res ; 54(10): e11035, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34378675

RESUMO

In this eight-year retrospective study, we evaluated the associations between climatic variations and the biological rhythms in plasma lipids and lipoproteins in a large population of Campinas, São Paulo state, Brazil, as well as temporal changes of outcomes of cardiovascular hospitalizations. Climatic variables were obtained at the Center for Meteorological and Climatic Research Applied to Agriculture (University of Campinas - Unicamp, Brazil). The plasma lipid databases surveyed were from 27,543 individuals who had their lipid profiles assessed at the state university referral hospital in Campinas (Unicamp). The frequency of hospitalizations was obtained from the Brazilian Public Health database (DATASUS). Temporal statistical analyses were performed using the methods Cosinor or Friedman (ARIMA) and the temporal series were compared by cross-correlation functions. In normolipidemic cases (n=11,892), significantly different rhythmicity was observed in low-density lipoprotein (LDL)- and high-density lipoprotein (HDL)-cholesterol (C) both higher in winter and lower in summer. Dyslipidemia (n=15,651) increased the number and amplitude of lipid rhythms: LDL-C and HDL-C were higher in winter and lower in summer, and the opposite occurred with triglycerides. The number of hospitalizations showed maximum and minimum frequencies in winter and in summer, respectively. A coincident rhythmicity was observed of lower temperature and humidity rates with higher plasma LDL-C, and their temporal series were inversely cross-correlated. This study shows for the first time that variations of temperature, humidity, and daylight length were strongly associated with LDL-C and HDL-C seasonality, but moderately to lowly associated with rhythmicity of atherosclerotic outcomes. It also indicates unfavorable cardiovascular-related changes during wintertime.


Assuntos
Doenças Cardiovasculares/epidemiologia , Clima , Lipídeos , Lipoproteínas , Brasil/epidemiologia , HDL-Colesterol/sangue , Humanos , Lipídeos/sangue , Lipoproteínas/sangue , Periodicidade , Estudos Retrospectivos , Estações do Ano , Triglicerídeos/sangue
10.
Nat Commun ; 12(1): 4759, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362916

RESUMO

Eco-evolutionary dynamics are essential in shaping the biological response of communities to ongoing climate change. Here we develop a spatially explicit eco-evolutionary framework which features more detailed species interactions, integrating evolution and dispersal. We include species interactions within and between trophic levels, and additionally, we incorporate the feature that species' interspecific competition might change due to increasing temperatures and affect the impact of climate change on ecological communities. Our modeling framework captures previously reported ecological responses to climate change, and also reveals two key results. First, interactions between trophic levels as well as temperature-dependent competition within a trophic level mitigate the negative impact of climate change on biodiversity, emphasizing the importance of understanding biotic interactions in shaping climate change impact. Second, our trait-based perspective reveals a strong positive relationship between the within-community variation in preferred temperatures and the capacity to respond to climate change. Temperature-dependent competition consistently results both in higher trait variation and more responsive communities to altered climatic conditions. Our study demonstrates the importance of species interactions in an eco-evolutionary setting, further expanding our knowledge of the interplay between ecological and evolutionary processes.


Assuntos
Evolução Biológica , Mudança Climática , Animais , Biodiversidade , Clima , Ecossistema , Modelos Biológicos , Fenótipo , Temperatura
11.
Nat Commun ; 12(1): 4866, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381045

RESUMO

Plants invest a considerable amount of leaf nitrogen in the photosynthetic enzyme ribulose-1,5-bisphosphate carboxylase-oxygenase (RuBisCO), forming a strong coupling of nitrogen and photosynthetic capacity. Variability in the nitrogen-photosynthesis relationship indicates different nitrogen use strategies of plants (i.e., the fraction nitrogen allocated to RuBisCO; fLNR), however, the reason for this remains unclear as widely different nitrogen use strategies are adopted in photosynthesis models. Here, we use a comprehensive database of in situ observations, a remote sensing product of leaf chlorophyll and ancillary climate and soil data, to examine the global distribution in fLNR using a random forest model. We find global fLNR is 18.2 ± 6.2%, with its variation largely driven by negative dependence on leaf mass per area and positive dependence on leaf phosphorus. Some climate and soil factors (i.e., light, atmospheric dryness, soil pH, and sand) have considerable positive influences on fLNR regionally. This study provides insight into the nitrogen-photosynthesis relationship of plants globally and an improved understanding of the global distribution of photosynthetic potential.


Assuntos
Nitrogênio/metabolismo , Fotossíntese , Folhas de Planta/metabolismo , Clorofila/metabolismo , Clima , Ecossistema , Internacionalidade , Modelos Teóricos , Fósforo/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo , Solo/química
12.
Nat Commun ; 12(1): 4675, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34344875

RESUMO

Recent studies conclude that the global coronavirus (COVID-19) pandemic decreased power sector CO2 emissions globally and in the United States. In this paper, we analyze the statistical significance of CO2 emissions reductions in the U.S. power sector from March through December 2020. We use Gaussian process (GP) regression to assess whether CO2 emissions reductions would have occurred with reasonable probability in the absence of COVID-19 considering uncertainty due to factors unrelated to the pandemic and adjusting for weather, seasonality, and recent emissions trends. We find that monthly CO2 emissions reductions are only statistically significant in April and May 2020 considering hypothesis tests at 5% significance levels. Separately, we consider the potential impact of COVID-19 on coal-fired power plant retirements through 2022. We find that only a small percentage of U.S. coal power plants are at risk of retirement due to a possible COVID-19-related sustained reduction in electricity demand and prices. We observe and anticipate a return to pre-COVID-19 CO2 emissions in the U.S. power sector.


Assuntos
COVID-19/epidemiologia , Centrais Elétricas/estatística & dados numéricos , Poluentes Atmosféricos/análise , Dióxido de Carbono/análise , Clima , Carvão Mineral/análise , Carvão Mineral/economia , Eletricidade , Combustíveis Fósseis/análise , Humanos , Centrais Elétricas/economia , Centrais Elétricas/tendências , SARS-CoV-2 , Estados Unidos/epidemiologia
13.
Sci Total Environ ; 794: 148718, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34217088

RESUMO

Amazonia experienced unusually devastating fires in August 2019, leading to huge regional and global environmental and economic losses. The increase in fires has been largely attributed to anthropogenic deforestation, but anomalous climate conditions could also have contributed. This study investigates the climate influence on Amazonia fires in August 2019 and underlying mechanisms, based on statistical correlation and multiple linear regression analyses of 2001-2019 satellite-based fire products and multiple observational or reanalyzed climate datasets. Positive fire anomalies in August 2019 were mainly located in southern Amazonia. These anomalies were mainly driven by low precipitation and relative humidity, which increased fuel dryness and contributed to 38.9 ± 9.5% of the 2019 anomaly in pyrogenic carbon emissions over the southern Amazonia. The dry conditions were associated with southerly wind anomalies over southern Amazonia that suppressed the climatological southward transport of water vapor originating from the Atlantic. The southerly wind anomalies were caused by the combination of a Gill-type cyclonic response to the warmer North Atlantic sea surface temperature (SST), and enhancement of the Walker and Hadley circulations over South America due to the colder SST in the eastern Pacific, and a mid-latitude wave train triggered by the warmer condition in the western Indian Ocean. Our study highlights, for the first time, the important role of Indian Ocean SST for fires in Amazonia. It also reveals how cold SST anomalies in the tropical eastern Pacific link the warm phase of the El Niño-Southern Oscillation (ENSO) in the preceding December-January to the dry-season fires in Amazonia. Our findings can develop theoretical basis of global tropical SST-based fire prediction, and have potential to improve prediction skill of extreme fires in Amazonia and thus to take steps to mitigate their impacts which is urgency given that dry conditions led to the extreme fires are becoming common in Amazonia.


Assuntos
Clima , Incêndios , Brasil , Mudança Climática , Estações do Ano
14.
PLoS One ; 16(7): e0255212, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34324570

RESUMO

Inferring the impact of climate upon the transmission of SARS-CoV-2 has been confounded by variability in testing, unknown disease introduction rates, and changing weather. Here we present a data model that accounts for dynamic testing rates and variations in disease introduction rates. We apply this model to data from Colombia, whose varied and seasonless climate, central port of entry, and swift, centralized response to the COVID-19 pandemic present an opportune environment for assessing the impact of climate factors on the spread of COVID-19. We observe strong attenuation of transmission in climates with sustained daily temperatures above 30 degrees Celsius and simultaneous mean relative humidity below 78%, with outbreaks occurring at high humidity even where the temperature is high. We hypothesize that temperature and relative humidity comodulate the infectivity of SARS-CoV-2 within respiratory droplets.


Assuntos
COVID-19/transmissão , SARS-CoV-2/patogenicidade , COVID-19/virologia , Clima , Colômbia , Humanos , Umidade , Pandemias/prevenção & controle , Temperatura , Tempo (Meteorologia)
15.
Environ Int ; 156: 106771, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34273873

RESUMO

Good-quality emission data are essential to validate national climate commitments and implement domestic policies. However, conventional bottom-up data collection is costly and subject to potential manipulation by stakeholders when data pass through their hands, which could pose challenges on the efficiency and effectiveness of compliance monitoring especially in developing countries. Satellite observations, specifically OCO-2 XCO2 measurements, are utilized in this study to develop a relatively independent and timely dataset for screening the attainment statuses of national and subnational CO2 mitigation goals in China's 13th Five-Year Plan (FYP, 2016-2020). We establish CO2 emission estimation models at both pixel and provincial levels. As interpolated with the pixel-level model, CO2 emissions of prefecture-level municipalities indicate that approximately three fifth of them had accomplished their individualized FYP mitigation goals by 2019, while our provincial-level estimation suggests that three quarters of provinces had attained theirs. More resources for compliance monitoring could thus be directed to other presumably-unattaining local governments. National aggregate absolute emissions showed 8.0-18.3% reduction in 2019 across three provincial models from the 2015 level, while national CO2 intensity dropped by 28.8-36.8% to imply attaining the 18% reduction goals.


Assuntos
Dióxido de Carbono , Objetivos , Dióxido de Carbono/análise , China , Clima
16.
Mar Environ Res ; 170: 105408, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34303298

RESUMO

The present study describes the larval and juvenile fish fauna of an estuary and its adjacent coastal area (Mondego estuary, Northwest coast of Portugal) and evaluates their function as nurseries for marine fish. For this, larvae and juveniles were sampled in both systems. The temporal and spatial patterns of the ichthyoplankton community were described for each system and related to the influence of environmental factors. Additionally, the recruitment pattern was evaluated based on the composition of juveniles. Results show a seasonal variation of larval density and community structure between and within systems, indicating a degree of segregation according to their ecological functional classification. Temperature was the most important environmental factor structuring the communities. The juvenile recruitment patterns observed show a different nursery function of the estuary and coastal area for early life stages of different species, reinforcing the need to integrate larval and juvenile stages to better understand fish life cycles and the connectivity between systems.


Assuntos
Ecossistema , Estuários , Animais , Clima , Peixes , Estações do Ano
17.
J Environ Manage ; 297: 113334, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34311250

RESUMO

Dam removal in the United States is becoming a common practice for stream restoration as these structures age, climate driven precipitation patterns change, and ecological uplift becomes desirable. Yet in highly urbanized watersheds, these dams may operate as retention basins removing pollutants and mitigating hydrological change. While elimination may be ecologically and economically advantageous, sediment and pollutant removal processes may be better protective of water quality and damaging flooding. In Central Virginia, we compared a watershed split between an urbanized subwatershed (>20% impervious surface encompassing 37.8% of the total watershed land surface) flowing through a 18 Ha reservoir with a rural subwatershed (<5% impervious encompassing 63.2% of the total watershed land surface) located in the James River and Chesapeake Bay watersheds. This reservoir is scheduled for removal in the near future. Comparisons of data suggest that while portions of the urbanized watershed are degraded, this condition is not reflected at the confluence where water quality more closely resembles the rural and minimally impervious subwatershed. This conclusion was further strengthened from data collected following an unexpected dam overtopping in August 2018 where the reservoir was temporarily drained because of safety concerns. After the draining, water quality reversed with the confluence resembling the urbanized rather than the rural subwatershed. Most significantly, water quality flowing into the James River quickly and significantly shifted from a good to a degraded condition. This case study suggests reservoirs in highly urbanized watersheds may serve as critical water quality improvement structures and removal as part of a stream restoration strategy must be carefully considered.


Assuntos
Rios , Poluentes Químicos da Água , Clima , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Qualidade da Água
18.
Nat Commun ; 12(1): 4116, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34238930

RESUMO

Increasing body and brain size constitutes a key macro-evolutionary pattern in the hominin lineage, yet the mechanisms behind these changes remain debated. Hypothesized drivers include environmental, demographic, social, dietary, and technological factors. Here we test the influence of environmental factors on the evolution of body and brain size in the genus Homo over the last one million years using a large fossil dataset combined with global paleoclimatic reconstructions and formalized hypotheses tested in a quantitative statistical framework. We identify temperature as a major predictor of body size variation within Homo, in accordance with Bergmann's rule. In contrast, net primary productivity of environments and long-term variability in precipitation correlate with brain size but explain low amounts of the observed variation. These associations are likely due to an indirect environmental influence on cognitive abilities and extinction probabilities. Most environmental factors that we test do not correspond with body and brain size evolution, pointing towards complex scenarios which underlie the evolution of key biological characteristics in later Homo.


Assuntos
Evolução Biológica , Encéfalo/anatomia & histologia , Fósseis/anatomia & histologia , Animais , Tamanho Corporal , Clima , Hominidae , Modelos Biológicos , Tamanho do Órgão , Filogenia , Temperatura
19.
Artigo em Inglês | MEDLINE | ID: mdl-34199394

RESUMO

Multiple sclerosis (MS) is a neurological disorder that progressively distorts the myelination of axons within the central nervous system (CNS). Increased core body temperature or metabolism as a result of exercise are common causes of short-term exacerbations of neurological symptoms in MS. About 60-80% of patients with MS experience a worsening of their symptoms when exposed to heat. In comparison, less data are available on the relationship between ambient meteorological conditions (e.g., temperature and relative humidity (RH)) and fluctuations in such variables in relation to MS symptoms. Thus, this study examined associations between time-lagged exposure to meteorological conditions and risk of a clinic visit due to MS among US veterans between 2010 and 2013. This study leveraged data from the Veterans Affairs (VA) and National Climactic Data Center (NCDC) for the continental US, partitioned into eight climate zones. We used a case crossover design to assess the risk of a MS clinic visit with respect to several meteorological conditions. Location-specific time-lagged daily (ambient) exposure to temperature, RH, and temperature variations (standard deviation (SD) of temperature) were computed (up to 30 days) for each case (i.e., day of MS visit) and control (a randomly assigned date ± 90-270 days prior to visit). Statistical analyses were conducted to examine independent associations between the selected meteorological conditions and risk of MS visits at the national and regional levels. A total of 533,066 patient visits received a MS diagnosis (International Classifications of Diseases (ICD)-9 code = 340). The Northeast (NE) and Upper Midwest (UMW) regions reported the highest frequency of clinic visits due to MS. Clinic visits were 9% more likely to occur in the spring, summer, and fall months (March-October) than in the winter (OR = 1.089; 95% CI = 1.076-1.103; p < 0.01). In the univariate analyses, the SD of temperature, temperature, and temperature-RH interaction were positively associated with an elevated risk of a MS clinic visit, while the RH was negatively associated with the risk for a clinic visit. In multivariate analyses, the strongest association of a MS clinic visit was observed with the SD of the temperature (OR = 1.012; 95% CI 1.008-1.017; p < 0.01). These associations between MS clinic visits and meteorological conditions varied across climate regions, with the strongest associations being observed in the LMW, UMW, DSW, and NE zones. The SD of the temperature was again the strongest associated predictor when examined regionally. Temperature variations and temperature-RH interactions (a proxy of the heat index) showed significant associations with MS clinic visits. These associations varied across climate regions when examined geographically. Our findings have implications for the management of MS in severe or recurrent cases, especially considering the impending changes in the daily temperature variations and intensity of the heatwaves expected with the intensification of global warming.


Assuntos
Temperatura Alta , Esclerose Múltipla , Clima , Humanos , Esclerose Múltipla/epidemiologia , Estações do Ano , Temperatura
20.
Ying Yong Sheng Tai Xue Bao ; 32(6): 1903-1918, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34212594

RESUMO

Co-driven by environmental change and human activity, global ecosystem has been experiencing rapid changes, with cascading effects on resources and environment. The changes of ecosystem status and its spatiotemporal evolution drivers, and the related resource and environmental effects have been recognized as the long standing topics of large-scale terrestrial ecosystem science. The coordinated observation networks distributed across different continents and the globe provide the valuable tools for observing and evaluating ecosystem state change, for revealing and elaborating mechanisms underlying ecosystem response, for cognizing and understanding ecosystem evolution, and for predicting and early-warning of ecosystem change. Committing to serving the continental-scale ecosystem science and supporting regional ecological environmental governance, this review first comprehensively analyzed the current status of ecological environment observation research networks, then proposed their development directions. This review advocated to develop a collaborative observation system with characteristics of multi-element, multi-interface, multi-medium, multi-process, multi-scale and multi-method, and to establish the new generation of continental ecosystem observation-experiment research network composed of high technology integration, regional distribution network, network management intellectualization, long-term observation & experiment, multi-functional model simulations, and remote data integration and resource sharing. We elaborated on the function orientation, design philosophy, design scheme, construction objectives and technical system of the research network. We hoped provide references for the development of terrestrial ecosystem observation network in China.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Clima , Política Ambiental , Humanos
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