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1.
Glob Chang Biol ; 30(7): e17391, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38946293

RESUMO

Heat released from soil organic carbon (SOC) decomposition (referred to as microbial heat hereafter) could alter the soil's thermal and hydrological conditions, subsequently modulate SOC decomposition and its feedback with climate. While understanding this feedback is crucial for shaping policy to achieve specific climate goal, it has not been comprehensively assessed. This study employs the ORCHIDEE-MICT model to investigate the effects of microbial heat, referred to as heating effect, focusing on their impacts on SOC accumulation, soil temperature and net primary productivity (NPP), as well as implication on land-climate feedback under two CO2 emissions scenarios (RCP2.6 and RCP8.5). The findings reveal that the microbial heat decreases soil carbon stock, predominantly in upper layers, and elevates soil temperatures, especially in deeper layers. This results in a marginal reduction in global SOC stocks due to accelerated SOC decomposition. Altered seasonal cycles of SOC decomposition and soil temperature are simulated, with the most significant temperature increase per unit of microbial heat (0.31 K J-1) occurring at around 273.15 K (median value of all grid cells where air temperature is around 273.15 K). The heating effect leads to the earlier loss of permafrost area under RCP8.5 and hinders its restoration under RCP2.6 after peak warming. Although elevated soil temperature under climate warming aligns with expectation, the anticipated accelerated SOC decomposition and large amplifying feedback on climate warming were not observed, mainly because of reduced modeled initial SOC stock and limited NPP with heating effect. These underscores the multifaceted impacts of microbial heat. Comprehensive understanding of these effects would be vital for devising effective climate change mitigation strategies in a warming world.


Assuntos
Carbono , Mudança Climática , Temperatura Alta , Solo , Solo/química , Carbono/análise , Microbiologia do Solo , Modelos Teóricos , Estações do Ano
2.
PeerJ ; 12: e17408, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38948203

RESUMO

Background: Over the last few decades, diabetes-related mortality risks (DRMR) have increased in Florida. Although there is evidence of geographic disparities in pre-diabetes and diabetes prevalence, little is known about disparities of DRMR in Florida. Understanding these disparities is important for guiding control programs and allocating health resources to communities most at need. Therefore, the objective of this study was to investigate geographic disparities and temporal changes of DRMR in Florida. Methods: Retrospective mortality data for deaths that occurred from 2010 to 2019 were obtained from the Florida Department of Health. Tenth International Classification of Disease codes E10-E14 were used to identify diabetes-related deaths. County-level mortality risks were computed and presented as number of deaths per 100,000 persons. Spatial Empirical Bayesian (SEB) smoothing was performed to adjust for spatial autocorrelation and the small number problem. High-risk spatial clusters of DRMR were identified using Tango's flexible spatial scan statistics. Geographic distribution and high-risk mortality clusters were displayed using ArcGIS, whereas seasonal patterns were visually represented in Excel. Results: A total of 54,684 deaths were reported during the study period. There was an increasing temporal trend as well as seasonal patterns in diabetes mortality risks with high risks occurring during the winter. The highest mortality risk (8.1 per 100,000 persons) was recorded during the winter of 2018, while the lowest (6.1 per 100,000 persons) was in the fall of 2010. County-level SEB smoothed mortality risks varied by geographic location, ranging from 12.6 to 81.1 deaths per 100,000 persons. Counties in the northern and central parts of the state tended to have high mortality risks, whereas southern counties consistently showed low mortality risks. Similar to the geographic distribution of DRMR, significant high-risk spatial clusters were also identified in the central and northern parts of Florida. Conclusion: Geographic disparities of DRMR exist in Florida, with high-risk spatial clusters being observed in rural central and northern areas of the state. There is also evidence of both increasing temporal trends and Winter peaks of DRMR. These findings are helpful for guiding allocation of resources to control the disease, reduce disparities, and improve population health.


Assuntos
Diabetes Mellitus , Humanos , Florida/epidemiologia , Estudos Retrospectivos , Diabetes Mellitus/mortalidade , Diabetes Mellitus/epidemiologia , Feminino , Masculino , Teorema de Bayes , Disparidades nos Níveis de Saúde , Pessoa de Meia-Idade , Fatores de Risco , Estações do Ano , Idoso , Adulto
3.
PeerJ ; 12: e17618, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38948218

RESUMO

Leaf inclination angle (LIA) and tillering impact the winter wheat (Triticum aestivum L.) population canopy structure. Understanding their effects on water use (WU) parameters and yield can guide water-saving strategies through population control. In this study, six near-isogenic lines (NILs) and their parents were selected as materials. These special materials were characterized by varying tillering at the current sowing density, a similar genetic background, and, particularly, a gradient in mean flag leaf LIA. The investigation focused on the jointing to early grain-filling stage, the peak water requirement period of wheat crops. Population-scale transpiration (PT) and evaporation from the soil surface (E) were partitioned from total evapotranspiration (ET) by the means of micro-lysimeters. The results showed decreased PT, E, and ET with increased population density (PD) within a narrow density range derived from varying tillering across genotypes. Significant correlations existed between PD and ET, E, and PT, especially in the wettest 2017-2018 growing season. Within such narrow PD range, all the correlations between WU parameters and PD were negative, although some correlations were not statistically significant, thereby suggesting the population structure's predominant impact. No significant correlation existed between LIA and both ET and PT within the LIA range of 35°-65°. However, significant correlations occurred between LIA and E in two growing seasons. Genotypes with similar LIA but different PD produced varied ET; while with similar PD, the four pairs of genotypes with different LIA each consumed similar ET, thus highlighting PD's more crucial role in regulating ET. The yield increased with higher LIA, and showed a significant correlation, emphasizing the LIA's significant effect on yield. However, no correlation was observed with PD, indicating the minor effect of tillering at the current sowing density. Therefore these results might offer valuable insights for breeding water-saving cultivars and optimizing population structures for effective field water conservation.


Assuntos
Folhas de Planta , Transpiração Vegetal , Solo , Triticum , Triticum/genética , Triticum/fisiologia , Triticum/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Solo/química , Estações do Ano , Água/metabolismo , Genótipo
4.
Int J Chron Obstruct Pulmon Dis ; 19: 1433-1445, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38948907

RESUMO

Background: Exacerbations of chronic obstructive pulmonary disease (COPD) were reported less frequently during the COVID-19 pandemic. We report real-world data on COPD exacerbation rates before and during this pandemic. Methods: Exacerbation patterns were analysed using electronic medical records or claims data of patients with COPD before (2017-2019) and during the COVID-19 pandemic (2020 through early 2022) in France, Germany, Italy, the United Kingdom and the United States. Data from each country were analysed separately. The proportions of patients with COPD receiving maintenance treatment were also estimated. Results: The proportion of patients with exacerbations fell 45-78% across five countries in 2020 versus 2019. Exacerbation rates in most countries were reduced by >50% in 2020 compared with 2019. The proportions of patients with an exacerbation increased in most countries in 2021. Across each country, seasonal exacerbation increases seen during autumn and winter in pre-pandemic years were absent during the first year of the pandemic. The percentage of patients filling COPD prescriptions across each country increased by 4.53-22.13% in 2019 to 9.94-34.17% in 2021. Conclusion: Early, steep declines in exacerbation rates occurred in 2020 versus 2019 across all five countries and were accompanied by a loss of the seasonal pattern of exacerbation.


Assuntos
COVID-19 , Progressão da Doença , Doença Pulmonar Obstrutiva Crônica , Humanos , COVID-19/epidemiologia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , SARS-CoV-2 , Estados Unidos/epidemiologia , França/epidemiologia , Reino Unido/epidemiologia , Pandemias , Itália/epidemiologia , Fatores de Tempo , Estações do Ano
5.
JAMA Netw Open ; 7(7): e2419258, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949812

RESUMO

Importance: In the context of emerging SARS-CoV-2 variants or lineages and new vaccines, it is key to accurately monitor COVID-19 vaccine effectiveness (CVE) to inform vaccination campaigns. Objective: To estimate the effectiveness of COVID-19 vaccines administered in autumn and winter 2022 to 2023 against symptomatic SARS-CoV-2 infection (with all circulating viruses and XBB lineage in particular) among people aged 60 years or older in Europe, and to compare different CVE approaches across the exposed and reference groups used. Design, Setting, and Participants: This case-control study obtained data from VEBIS (Vaccine Effectiveness, Burden and Impact Studies), a multicenter study that collects COVID-19 and influenza data from 11 European sites: Croatia; France; Germany; Hungary; Ireland; Portugal; the Netherlands; Romania; Spain, national; Spain, Navarre region; and Sweden. Participants were primary care patients aged 60 years or older with acute respiratory infection symptoms who were recruited at the 11 sites after the start of the COVID-19 vaccination campaign from September 2022 to August 2023. Cases and controls were defined as patients with positive and negative, respectively, reverse transcription-polymerase chain reaction (RT-PCR) test results. Exposures: The exposure was COVID-19 vaccination. The exposure group consisted of patients who received a COVID-19 vaccine during the autumn and winter 2022 to 2023 vaccination campaign and 14 days or more before symptom onset. Reference group included patients who were not vaccinated during or in the 6 months before the 2022 to 2023 campaign (seasonal CVE), those who were never vaccinated (absolute CVE), and those who were vaccinated with at least the primary series 6 months or more before the campaign (relative CVE). For relative CVE of second boosters, patients receiving their second booster during the campaign were compared with those receiving 1 booster 6 months or more before the campaign. Main Outcomes and Measures: The outcome was RT-PCR-confirmed, medically attended, symptomatic SARS-CoV-2 infection. Four CVE estimates were generated: seasonal, absolute, relative, and relative of second boosters. CVE was estimated using logistic regression, adjusting for study site, symptom onset date, age, chronic condition, and sex. Results: A total of 9308 primary care patients were included, with 1687 cases (1035 females; median [IQR] age, 71 [65-79] years) and 7621 controls (4619 females [61%]; median [IQR] age, 71 [65-78] years). Within 14 to 89 days after vaccination, seasonal CVE was 29% (95% CI, 14%-42%), absolute CVE was 39% (95% CI, 6%-60%), relative CVE was 31% (95% CI, 15% to 44%), and relative CVE of second boosters was 34% (95% CI, 18%-47%) against all SARS-CoV-2 variants. In the same interval, seasonal CVE was 44% (95% CI, -10% to 75%), absolute CVE was 52% (95% CI, -23% to 82%), relative CVE was 47% (95% CI, -8% to 77%), and relative CVE of second boosters was 46% (95% CI, -13% to 77%) during a period of high XBB circulation. Estimates decreased with time since vaccination, with no protection from 180 days after vaccination. Conclusions and Relevance: In this case-control study among older Europeans, all CVE approaches suggested that COVID-19 vaccines administered in autumn and winter 2022 to 2023 offered at least 3 months of protection against symptomatic, medically attended, laboratory-confirmed SARS-CoV-2 infection. The effectiveness of new COVID-19 vaccines against emerging SARS-CoV-2 variants should be continually monitored using CVE seasonal approaches.


Assuntos
Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Estações do Ano , Eficácia de Vacinas , Humanos , Idoso , COVID-19/prevenção & controle , COVID-19/epidemiologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/uso terapêutico , Feminino , Europa (Continente)/epidemiologia , Masculino , SARS-CoV-2/imunologia , Pessoa de Meia-Idade , Estudos de Casos e Controles , Idoso de 80 Anos ou mais , Vacinação/estatística & dados numéricos , População Europeia
6.
Recurso na Internet em Português | LIS - Localizador de Informação em Saúde | ID: lis-49634

RESUMO

Quando se trata de proteção contra a gripe, Antônio Marcos Ferreira da Silva, 60 anos, aposentado, não perde tempo. Todos os anos, assim que fica sabendo que a imunização está aberta ao seu público, ele corre para a unidade básica de saúde mais próxima.


Assuntos
Vacinação , Influenza Humana , Estações do Ano
7.
J Med Virol ; 96(6): e29719, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38873911

RESUMO

This study aimed to determine the timing patterns of the initial respiratory syncytial virus (RSV) infection and to identify the factors influencing disease severity in infants of varying health status. A retrospective study was conducted at the Affiliated Children's Hospital of Chongqing Medical University from 2012 to 2022. The timing of the first RSV infection was estimated in infants with differing health status using correlation analysis, considering their birth time. Logistic regression was utilized to identify factors influencing severe RSV infection in these infants. RSV detection primarily occurred in the winter and spring. Epidemic season and peak timing of RSV were not significantly affected by health status or the COVID-19 pandemic. A strong positive correlation was observed between the age at RSV infection and the interval from birth to the RSV peak season. Infants born during the RSV epidemic season exhibited a higher likelihood of infection within the first 2 months postbirth. In contrast, those born outside the RSV epidemic season were more susceptible to infection during the subsequent peak. Notably, infants with pre-existing health conditions contracted RSV at an earlier age compared to their healthy counterparts. Among healthy infants, severe RSV infection was associated with sex, age, and timing of infection. For infants with underlying conditions, severe RSV infection was primarily related to age and timing of infection. The initial timing of RSV infection in infants varied depending on their health status. Young age and infection timing during the RSV epidemic season were significant risk factors for severe RSV infection. These findings provide a theoretical basis for optimizing immunization strategies for infants with diverse health conditions.


Assuntos
Infecções por Vírus Respiratório Sincicial , Estações do Ano , Índice de Gravidade de Doença , Humanos , Infecções por Vírus Respiratório Sincicial/epidemiologia , Lactente , Masculino , Feminino , Estudos Retrospectivos , Recém-Nascido , Vírus Sincicial Respiratório Humano , Hospitalização/estatística & dados numéricos , Fatores de Risco , COVID-19/epidemiologia , Nível de Saúde , China/epidemiologia , Fatores de Tempo
8.
Sci Total Environ ; 939: 173573, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38823703

RESUMO

The impact of global warming on plant abundance has been widely discussed, but it remains unclear how warming affects plant physiological traits, and how these traits contribute to the abundance of aquatic plants. We explored the adjustments in physiological traits of two common aquatic plant species (Potamogeton crispus L. and Elodea canadensis Michx.) and their links to plant abundance in three temperature treatments by determining twelve physiological traits and plant abundance over an 11-month period in outdoor mesocosms. This mesocosms facility has been running uninteruptedly for 16 years, rendering the plants a unique opportunity to adapt to the warming differences. We found that 1) warming reduced the starch storage in winter for P. crispus and in summer for E. canadensis while increased the nitrogenous substances (e.g., TN, FAA, and proline) in winter for P. crispus. 2) For E. canadensis, TC, starch, SC, and sucrose contents were higher in summer than in winter regardless of warming, while TC, SC, and sucrose contents were lower in summer for P. crispus. 3) Warming decreased the association strength between physiological traits and plant abundance for P. crispus but enhanced it for E. canadensis. 4) E. canadensis showed increased interaction strength among physiological traits under warming, indicating increased metabolic exertion in the response to warming, which contributed to the reduction in abundance. Trait interaction strength of P. crispus was reduced under warming, but with less impact on plant abundance compared with E. canadensis. Our study emphasizes that warming alters the network of plant physiological traits and their contribution to abundance and that different strengths of susceptibility to warming of the various plant species may alter the composition of plant communities in freshwater ecosystems.


Assuntos
Aquecimento Global , Hydrocharitaceae/fisiologia , Potamogetonaceae/fisiologia , Estações do Ano , Plantas
9.
Infect Dis Now ; 54(4S): 104889, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38849256

RESUMO

The XXXIIIrd Paris Summer Olympics followed by the XVIIth Paralympics Games will take place in France, predominantly in and around Paris, from July 26 to September 8, 2024. Public health stakeholders and decision-makers are called upon to set up or strengthen surveillance systems in areas hosting Olympic or Paralympic Games (OPGs) or large-scale international competitions, the objective being to detect and manage outbreaks should they occur during that period. We undertook a narrative review of the literature so as to identify major reported infectious disease outbreaks linked with or during OPGs / international sporting events during warm seasons. Our review found that since 1992, Summer Olympic and Paralympic games and international football competitions have been associated with sporadic cases of infectious diseases, principally respiratory, gastrointestinal/foodborne, but not with any major communicable or other infectious disease outbreak. Communicable disease risks should be assessed for the population taken as a whole, an integrated ecosystem with several population compartments potentially exchanging pathogens among one another. Although the Games afford an opportunity to federate or invent new surveillance systems to fill a gap, surveillance should be based on existing medical and laboratory systems, proven tools reinforced with the necessary human and financial resources. The performance of the public health surveillance system is ultimately predicated on trust on the part of participating clinicians, policymakers and international partners.


Assuntos
Doenças Transmissíveis , Surtos de Doenças , Estações do Ano , Esportes , Humanos , Doenças Transmissíveis/epidemiologia , Saúde Pública/métodos , Monitoramento Epidemiológico
10.
BMJ Open ; 14(6): e084804, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858146

RESUMO

BACKGROUND: Long-term exposure to air pollution has been linked to cancer incidence. However, the evidence is limited regarding the effect of short-term exposure to air pollution on cancer mortality. OBJECTIVES: This study aimed to investigate associations between short-term exposure to air pollutants (sulfur dioxide (SO2), nitrogen dioxide (NO2), particulate matter with an aerodynamic diameter <10 mm (PM10) and PM2.5) and cancer daily mortality. METHODS: This study used air quality, meteorological and daily cancer death data from 2014 to 2019 in Hangzhou, China. Generalised additive models (GAM) with quasi-Poisson regression were used to analyse the associations between air pollutants and cancer mortality with adjustment for confounding factors including time trends, day of week, temperature and humidity. Then, we conducted stratified analyses by sex, age, season and education. In addition, stratified analyses of age, season and education were performed within each sex to determine whether sex difference was modified by such factors. RESULTS: After adjusting for potential confounders, the GAM results indicated a statistically significant relationship between increased cancer mortality and elevated air pollution concentrations, but only in the female population. For every 10 µg/m3 rise in pollutant concentration, the increased risk of cancer death in females was 6.82% (95% CI 3.63% to 10.10%) for SO2 on lag 03, and 2.02% (95% CI 1.12% to 2.93%) for NO2 on lag 01 and 0.89% (95% CI 0.46% to 1.33%) for PM10 on lag 03 and 1.29% (95% CI 0.64% to 1.95%) for PM2.5 on lag 03. However, no statistically significant association was found among males. Moreover, the differences in effect sizes between males and females were more pronounced during the cold season, among the elderly and among subjects with low levels of education. CONCLUSIONS: Increased cancer mortality was only observed in females with rising concentrations of air pollutants. Further research is required to confirm this sex difference. Advocate for the reduction of air pollutant emissions to protect vulnerable groups.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Exposição Ambiental , Neoplasias , Dióxido de Nitrogênio , Material Particulado , Dióxido de Enxofre , Humanos , Neoplasias/mortalidade , China/epidemiologia , Feminino , Masculino , Poluição do Ar/efeitos adversos , Material Particulado/efeitos adversos , Material Particulado/análise , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Pessoa de Meia-Idade , Exposição Ambiental/efeitos adversos , Dióxido de Enxofre/análise , Dióxido de Enxofre/efeitos adversos , Idoso , Dióxido de Nitrogênio/análise , Dióxido de Nitrogênio/efeitos adversos , Adulto , Estações do Ano , Adulto Jovem , Adolescente , Criança , Fatores Sexuais
11.
PLoS One ; 19(6): e0303841, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38865352

RESUMO

A significant crop pest, Mythimna loreyi, migrates annually to Korea and has been frequently observed in rice and corn fields. However, the phenology of this pest, particularly in relation to its ecological interactions and host crop seasons in Korea, remains poorly understood. This study aims to clarify the timing of the second generation of M. loreyi in Korea to enhance pest management strategies. To achieve this, we developed temperature-dependent models for developmental and ovipositional rates, studying these processes across five constant temperatures (15, 20, 25, 30, and 35°C). Our models, which showed a high correlation with observed data (r2 ≥ 0.93), include a theoretical approach that combines the developmental variation of immatures with the necessary degree-days for 50% egg laying and complete egg development. These predictions allow for the forecasting of the second generation's occurrence, with relatively small deviations (one to three days) observed at two different field sites. The insights from this study are critical for both understanding the ecology of M. loreyi and for informing practical management decisions, such as optimal placement of barriers to prevent immigration and strategies for controlling local populations.


Assuntos
Oviposição , Temperatura , Animais , Oviposição/fisiologia , Feminino , República da Coreia , Mariposas/fisiologia , Mariposas/crescimento & desenvolvimento , Modelos Biológicos , Estações do Ano
12.
PLoS One ; 19(6): e0302433, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38865356

RESUMO

The timing of American horseshoe crab (Limulus polyphemus) spawning behavior along the coast of Florida (United States) is generally associated with the highest tides during the spring and fall lunar cycles. All Florida estuaries support horseshoe crab populations, but tidal characteristics vary markedly among locations, which may influence the timing of horseshoe crab spawning behavior. The Indian River Lagoon is a large microtidal estuary on Florida's east coast. Given the microtidal nature of the lagoon, it is unclear which environmental factors affect horseshoe spawning. In 2019, volunteers of Florida Horseshoe Crab Watch conducted daily surveys at two sites in the northern Indian River Lagoon during peak spawning months (February-April). During each survey, volunteers counted all spawning horseshoe crabs and recorded environmental variables, including water temperature, air temperature, wind speed, wind direction, salinity, and tide height. We developed a suite of negative-binomial regression models to quantify relationships between the number of spawning horseshoe crabs and environmental factors. Modeling results indicated a positive relationship between onshore wind speed and number of spawning horseshoe crabs. Our study suggests that in the absence of tidal cues, onshore wind speed may be an important driver of horseshoe crab spawning activity in microtidal estuarine systems.


Assuntos
Caranguejos Ferradura , Animais , Florida , Caranguejos Ferradura/fisiologia , Temperatura , Estações do Ano , Estuários , Reprodução/fisiologia , Vento , Ondas de Maré , Salinidade , Rios
13.
PLoS One ; 19(6): e0305369, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38865434

RESUMO

Determining space use for species is fundamental to understanding their ecology, and tracking animals can reveal insights into their spatial ecology on home ranges and territories. Recent technological advances have led to GPS-tracking devices light enough for birds as small as ~30 g, creating novel opportunities to remotely monitor fine-scale movements and space use for these smaller species. We tested whether miniaturized GPS tags can allow us to understand space use of migratory birds away from their capture sites and sought to understand both pre-breeding space use as well as territory and habitat use on the breeding grounds. We used GPS tags to characterize home ranges on the breeding grounds for a migratory songbird with limited available breeding information, the Golden-crowned Sparrow (Zonotrichia atricapilla). Using GPS points from 23 individuals across 26 tags (three birds tagged twice), we found home ranges in Alaska and British Columbia were on average 44.1 ha (95% kernel density estimate). In addition, estimates of territory sizes based on field observations (mean 2.1 ha, 95% minimum convex polygon [MCP]) were three times smaller than 95% MCPs created using GPS tags (mean 6.5 ha). Home ranges included a variety of land cover classes, with shrubland particularly dominant (64-100% of home range cover for all but one bird). Three birds tracked twice returned to the same breeding area each year, supporting high breeding site fidelity for this species. We found reverse spring migration for five birds that flew up to 154 km past breeding destinations before returning. GPS-tracking technology allowed for critical ecological insights into this migratory species that breeds in very remote locations.


Assuntos
Migração Animal , Sistemas de Informação Geográfica , Comportamento de Retorno ao Território Vital , Estações do Ano , Pardais , Animais , Migração Animal/fisiologia , Pardais/fisiologia , Comportamento de Retorno ao Território Vital/fisiologia , Cruzamento , Ecossistema , Colúmbia Britânica , Alaska , Comportamento de Nidação/fisiologia
14.
Sci Total Environ ; 941: 173572, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823707

RESUMO

Forest canopy gaps can influence understorey microclimate and ecosystem functions such as decomposition. Gaps can arise from silviculture or tree mortality, increasingly influenced by climate change. However, to what degree canopy gaps affect the buffered microclimate in the understorey under macroclimatic changes is unclear. We, therefore, investigated the effect of forest gaps differing in structure and size (25 gaps: single tree gaps up to 0.67 ha cuttings) on microclimate and soil biological activity compared to closed forest in a European mixed floodplain forest. During the investigation period in the drought year 2022 between May and October, mean soil moisture and temperature as well as soil and air temperature fluctuations increased with increasing openness. In summer, the highest difference of monthly means between cuttings and closed forest in the topsoil was 3.98 ± 9.43 % volumetric moisture and 2.05 ± 0.89 °C temperature, and in the air at 30 cm height 0.61 ± 0.35 °C temperature. For buffering, both the over- and understorey tree layers appeared as relevant with a particularly strong influence of understorey density on soil temperature. Three experiments, investigating soil biological activity by quantifying decomposition rates of tea and wooden spatulas as well as mesofauna feeding activity with bait-lamina stripes, revealed no significant differences between gaps and closed forest. However, we found a positive significant effect of mean soil temperature on feeding activity throughout the season. Although soil moisture decreased during this period, it showed no counteracting effect on feeding activity. Generally, very few significant relationships were observed between microclimate and soil biological activity in single experiments. Despite the dry growing season, decomposition rates remained high, suggesting temperature had a stronger influence than soil moisture. We conclude that the microclimatic differences within the gap gradient of our experiment were not strong enough to affect soil biological activity considerably.


Assuntos
Mudança Climática , Florestas , Microclima , Solo , Solo/química , Temperatura , Árvores , Ecossistema , Estações do Ano
15.
EBioMedicine ; 104: 105182, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38838470

RESUMO

BACKGROUND: Human milk oligosaccharides (HMOs), their determinants, infant gut microbiota and health are under extensive research; however, seldom jointly addressed. Leveraging data from the HELMi birth cohort, we investigated them collectively, considering maternal and infant secretor status. METHODS: HMO composition in breastmilk collected 3 months postpartum (n = 350 mothers) was profiled using high-performance liquid chromatography. Infant gut microbiota taxonomic and functional development was studied at 3, 6, and 12 months (n = 823 stool samples) via shotgun metagenomic sequencing, focusing on HMO metabolism via glycoside hydrolase (GH) analysis. Maternal and infant secretor statuses were identified through phenotyping and genotyping, respectively. Child health, emphasizing allergies and antibiotics as proxies for infectious diseases, was recorded until 2 years. FINDINGS: Mother's parity, irritable bowel syndrome, gestational diabetes, and season of milk collection associated with HMO composition. Neither maternal nor infant secretor status associated with infant gut microbiota, except for a few taxa linked to individual HMOs. Analysis stratified for birth mode revealed distinct patterns between the infant gut microbiota and HMOs. Child health parameters were not associated to infant or maternal secretor status. INTERPRETATION: This comprehensive exploration unveils intricate links between secretor genotype, maternal factors, HMO composition, infant microbiota, and child health. Understanding these nuanced relationships is paramount for refining strategies to optimize early life nutrition and its enduring impact on long-term health. FUNDING: Sweet Crosstalk EU H2020 MSCA ITN, Academy of Finland, Mary and Georg C. Ehrnrooth Foundation, Päivikki and Sakari Sohlberg Foundation, and Tekes.


Assuntos
Microbioma Gastrointestinal , Leite Humano , Oligossacarídeos , Paridade , Estações do Ano , Humanos , Leite Humano/química , Leite Humano/metabolismo , Oligossacarídeos/metabolismo , Oligossacarídeos/análise , Feminino , Finlândia , Lactente , Coorte de Nascimento , Metagenômica/métodos , Gravidez , Recém-Nascido , Adulto , Metagenoma , Masculino , Fezes/microbiologia
16.
Sci Total Environ ; 941: 173664, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38838998

RESUMO

Ecological stoichiometry serves as a valuable tool for comprehending biogeochemical cycles within grassland ecosystems. The impact of grazing time on the concentration and stoichiometric characteristics of carbon (C), nitrogen (N), and phosphorus (P) in desert steppe ecosystems remains ambiguous. This research was carried out in a desert grassland utilizing a completely randomized experimental design. Four distinct grazing time treatments were implemented: fenced grassland (FG, control), delay to start and early to end grazing grassland (DEG), delay to start grazing grassland (DG), and traditional grazing grassland (TG). The patterns of C, N, and P concentrations and their stoichiometry in various components of the ecosystem, as well as their driving factors under different grazing times were examined. The results showed that grazing time positively influenced C and N concentrations in leaves, while negatively affecting N concentrations in roots. TG had a significant positive effect on soil P concentrations but a negative effect on soil C:P and N:P ratios. Plant C:N, C:P, and N: P ratios were mainly influenced by N and P. The soil C:N ratio was primarily influenced by soil N, the soil C:P ratio was affected by both soil C and P, and the soil N:P ratio was influenced by both soil N and P. The growth of plants in desert steppes is mainly limited by P; however, as grazing time increased, P limitation gradually decreased and the N cycling rate increased. C-N, C-P, and N-P in various plant organs and soils demonstrated significant anisotropic growth relationships at different grazing times. Soil organic carbon, pH, and soil total phosphorus were the main driving factors that affected changes in ecological C:N:P stoichiometry. These results will help improve grassland management and anticipate the response of grassland systems to external disturbances with greater accuracy.


Assuntos
Clima Desértico , Pradaria , Nitrogênio , Fósforo , Estações do Ano , Solo , Fósforo/análise , Nitrogênio/análise , Solo/química , Herbivoria , Ciclo do Nitrogênio , Carbono/metabolismo , Carbono/análise , China , Animais
17.
Sci Total Environ ; 941: 173659, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38839015

RESUMO

Microplastics (MPs) are found in a wide range of ecosystems, from the Arctic to the deep ocean. However, there is no data on their presence in terrestrial mammals that inhabit the Selva Maya. The aim of this study is to detect the presence of MPs in the feces of the Baird's tapir (Tapirus bairdii) from the region of Calakmul, located in the Yucatan Peninsula, Mexico. We analyzed 129 fecal samples collected during 2017 and 2018, obtaining 57 and 72 samples during the rainy and dry seasons respectively. Sixty-eight percent of the samples contained 743 MPs with a mean of 19.3 ± 28.1 MPs/kg of dry weight (DW) feces in both years. An inter-annual variation in the average abundance of microplastic was observed during the two-year period (2017-2018), with a 72 % increase in these plastic particles in feces. Fourteen polymers were identified, with ethylene vinyl acetate (EVA), polypropylene (PP) and polyester (PES) being the most abundant during both years. Although the effects of MPs on the health of tapirs are not known, their presence is cause for concern. There is an urgent need for the implementation of appropriate plastic waste management programs in communities of the Selva Maya to diminish the consumption of MPs in species including humans where they pose a significant risk to health. ENVIRONMENTAL IMPLICATIONS: The use of plastics worldwide is increasing every day, so the presence of microplastics is and will continue to be a major environmental problem. It is known that contaminants can adhere to plastics, making them hazardous materials. Microplastics can contaminate remote areas such as Biosphere Reserves. Terrestrial species such as the tapir can ingest microplastics, putting their health at risk. Knowing the dispersion of microplastics is very important in order to manage them properly, taking into account their emission sources and type of polymer.


Assuntos
Monitoramento Ambiental , Fezes , Microplásticos , Perissodáctilos , Animais , Microplásticos/análise , Fezes/química , México , Poluentes Químicos da Água/análise , Plásticos/análise , Estações do Ano
18.
J Environ Manage ; 363: 121287, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38843733

RESUMO

Despite concerted efforts in emission control, air pollution control remains challenging. Urban planning has emerged as a crucial strategy for mitigating PM2.5 pollution. What remains unclear is the impact of urban form and their interactions with seasonal changes. In this study, base on the air quality monitoring stations in the Yangtze River Delta urban agglomeration, the relationship between urban spatial indicators (building morphology and land use) and PM2.5 concentrations was investigated using full subset regression and variance partitioning analysis, and seasonal differences were further analysed. Our findings reveal that PM2.5 pollution exhibits different sensitivities to spatial scales, with higher sensitivity to the local microclimate formed by the three-dimensional structure of buildings at the local scale, while land use exerts greater influence at larger scales. Specifically, land use indicators contributed sustantially more to the PM2.5 prediction model as buffer zone expand (from an average of 2.41% at 100 m range to 47.30% at 5000 m range), whereas building morphology indicators display an inverse trend (from an average of 13.84% at 100 m range to 1.88% at 5000 m range). These results enderscore the importance of considering building morphology in local-scale urban planning, where the increasing building height can significantly enhance the disperion of PM2.5 pollution. Conversely, large-scale urban planning should prioritize the mixed use of green spaces and construction lands to mitigate PM2.5 pollution. Moreover, the significant seasonal differences in the ralationship between urban spatical indicatiors and PM2.5 pollution were observed. Particularly moteworthy is the heightened association between forest, water indicators and PM2.5 concentrations in summer, indicating the urban forests may facilitate the formation of volatile compunds, exacerbating the PM2.5 pollution. Our study provides a theoretical basis for addressing scale-related challenges in urban spatial planning, thereby forstering the sustainable development of cities.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Material Particulado , Rios , Estações do Ano , Material Particulado/análise , Poluição do Ar/análise , Poluentes Atmosféricos/análise , Rios/química , China , Urbanização
19.
J Environ Manage ; 363: 121398, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38852404

RESUMO

Scaling irrigated agriculture is a global strategy to mitigate food insecurity concerns. While expanding irrigated agriculture is critical to meeting food production demands, it is important to consider how these land use and land cover changes (LULCC) may alter the water resources of landscapes and impact the spatiotemporal epidemiology of disease. Here, a generalizable method is presented to inform irrigation development decision-making aimed at increasing crop production through irrigation while simultaneously mitigating malaria risk to surrounding communities. Changes to the spatiotemporal patterns of malaria vector (Anopheles gambiae s.s.) suitability, driven by irrigated agricultural expansion, are presented for Malawi's rainy and dry seasons. The methods presented may be applied to other geographical areas where sufficient irrigation and malaria prevalence data are available. Results show that approximately 8.60% and 1.78% of Malawi is maximally suitable for An. gambiae s.s. breeding in the rainy and dry seasons, respectively. However, the proposed LULCC from irrigated agriculture increases the maximally suitable land area in both seasons: 15.16% (rainy) and 2.17% (dry). Proposed irrigation development sites are analyzed and ranked according to their likelihood of increasing malaria risk for those closest to the schemes. Results illustrate how geospatial information on the anticipated change to the malaria landscape driven by increasing irrigated agricultural extent can assist in altering development plans, amending policies, or reassessing water resource management strategies to mitigate expected changes in malaria risk.


Assuntos
Irrigação Agrícola , Malária , Recursos Hídricos , Malária/prevenção & controle , Malaui , Doenças Transmitidas por Vetores/prevenção & controle , Animais , Estações do Ano , Agricultura/métodos , Anopheles
20.
J Environ Manage ; 363: 121297, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38852406

RESUMO

In the southeastern USA, lack of historical fire regimes often leads to hardwood encroachment into early successional plant communities and managed pine stands, reducing wildlife value and timber yields. Land managers lack information on how firing technique interacts with fire season to influence plant communities. We designed an experiment to quantify these interactions in east-central Mississippi with pairs of 4 m × 8 m plots randomly assigned a backing and heading fire in each of three seasons: February (Feb), May-June (May/Jun), and September-October (Sep/Oct). We used thermocouples to monitor fire temperature and tagged midstory trees to monitor response. We lit heading fires with an 18-25 kph wind generated by a backpack blower and backing fires into the ambient wind. Despite backing fires producing longer residence times than heading fires and raising temperature above the lethal threshold of 60 °C an average of 54 s longer, firing technique did not influence midstory response one growing season post-fire. Backing and heading fires produced similar maximum temperatures. For both firing techniques, May/Jun resulted in the highest midstory mortality rates which were 3-fold greater than Sep/Oct and 4-fold greater than Feb. Among all three fire seasons, trees with a 2.5 cm diameter at breast height (DBH) had approximately a 75% chance of top-kill which decreased to <20% as trees approached 6.5 cm DBH. We found no effects of fire season on fire temperature, rate of spread, flame height, or percent crown scorch. We found no significant interactions between fire season and firing technique. Understory analysis revealed Sep/Oct produced the greatest increase in forb coverage, May/Jun resulted in the most grass coverage, and Feb produced the most brambles (Rubus spp.). On sites with similar species, weather, and fuel conditions to ours, land managers should emphasize fire season over firing technique for midstory control and understory manipulation. Where midstory hardwood control with fire is a priority, fire return intervals should be frequent enough to prevent trees from exceeding 2.5 cm DBH to avoid trees escaping fire's reach. These data can help managers reduce midstory competition with crop trees and promote understory development for wildlife.


Assuntos
Incêndios , Estações do Ano , Árvores , Mississippi
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