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1.
Codas ; 36(3): e20220330, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38695436

RESUMO

PURPOSE: The Awake Breathing Pattern Assessment (ABPA) is a prototypical clinical grid recently designed through an international consensus of Speech and Language Pathologists (SLPs) to categorize the awake and habitual breathing pattern during the orofacial myofunctional assessment. This cross-sectional study aims to explore the psychometric properties of the ABPA in a preschool population. METHODS: 133 children from 2;11 to 6 years old were assessed with the ABPA. The percentage of time spent breathing through the mouth was objectively measured by a CO2 sensor and used as a baseline measurement. We first performed a multivariate Latent Profile Analysis based on the CO2 measurement and a parental questionnaire to define the number of categories that best characterize the breathing pattern. Subsequently, we assessed the intra- and inter-rater reliability, internal consistency criterion validity, construct validity and sensitivity and specificity. RESULTS: The awake breathing pattern can best be described by two groups: nasal and mouth breathing. The ABPA, initially designed in three groups, was adjusted accordingly. This final version showed excellent intra-rater and inter-rater reliability. There was a significant correlation between the ABPA and the CO2 measurement. The ABPA showed a fair sensitivity and a good specificity. CONCLUSION: The reference tool based on CO2 data was used in children for the first time and was found to be reliable. The ABPA is a suitable tool for SLPs to confirm the diagnosis of mouth breathing in preschool children if more sensitive screening tools, like parental questionnaires, are used beforehand.


Assuntos
Respiração Bucal , Humanos , Respiração Bucal/diagnóstico , Respiração Bucal/fisiopatologia , Pré-Escolar , Estudos Transversais , Reprodutibilidade dos Testes , Feminino , Masculino , Criança , Psicometria , Sensibilidade e Especificidade , Inquéritos e Questionários , Vigília/fisiologia , Respiração , Dióxido de Carbono/análise
2.
Sci Rep ; 14(1): 11023, 2024 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744922

RESUMO

Encroachment of vascular plants (VP) in temperate raised bogs, as a consequence of altered hydrological conditions and nutrient input, is widely observed. Effects of such vegetation shift on water and carbon cycles are, however, largely unknown and identification of responsible plant physiological traits is challenging. Process-based modelling offers the opportunity of gaining insights into ecosystem functioning beyond observations, and to infer decisive trait shifts of plant functional groups. We adapted the Soil-Vegetation-Atmosphere Transfer model pyAPES to a temperate raised bog site by calibration against measured peat temperature, water table and surface CO2 fluxes. We identified the most important traits determining CO2 fluxes by conducting Morris sensitivity analysis (MSA) under changing conditions throughout the year and simulated VP encroachment. We further investigated transferability of results to other sites by extending MSA to parameter ranges derived from literature review. We found highly variable intra-annual plant traits importance determining ecosystem CO2 fluxes, but only a partial shift of importance of photosynthetic processes from moss to VP during encroachment. Ecosystem respiration was dominated by peat respiration. Overall, carboxylation rate, base respiration rate and temperature sensitivity (Q10) were most important for determining bog CO2 balance and parameter ranking was robust even under the extended MSA.


Assuntos
Dióxido de Carbono , Ecossistema , Plantas , Estações do Ano , Áreas Alagadas , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análise , Plantas/metabolismo , Solo/química , Fotossíntese , Ciclo do Carbono , Temperatura , Modelos Teóricos , Atmosfera
3.
Curr Opin Crit Care ; 30(3): 251-259, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38690954

RESUMO

PURPOSE OF REVIEW: To describe current and near future developments and applications of CO2 kinetics in clinical respiratory and cardiovascular monitoring. RECENT FINDINGS: In the last years, we have witnessed a renewed interest in CO2 kinetics in relation with a better understanding of volumetric capnography and its derived parameters. This together with technological advances and improved measurement systems have expanded the monitoring potential of CO2 kinetics including breath by breath continuous end-expiratory lung volume and continuous noninvasive cardiac output. Dead space has slowly been gaining relevance in clinical monitoring and prognostic evaluation. Easy to measure dead space surrogates such as the ventilatory ratio have demonstrated a strong prognostic value in patients with acute respiratory failure. SUMMARY: The kinetics of carbon dioxide describe many relevant physiological processes. The clinical introduction of new ways of assessing respiratory and circulatory efficiency based on advanced analysis of CO2 kinetics are paving the road to a long-desired goal in clinical monitoring of critically ill patients: the integration of respiratory and circulatory monitoring during mechanical ventilation.


Assuntos
Capnografia , Dióxido de Carbono , Humanos , Dióxido de Carbono/análise , Capnografia/métodos , Monitorização Fisiológica/métodos , Respiração Artificial/métodos , Cinética , Débito Cardíaco/fisiologia , Biomarcadores , Espaço Morto Respiratório/fisiologia
4.
PLoS One ; 19(5): e0302139, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38717995

RESUMO

Cover crops have the potential to mitigate climate change by reducing negative impacts of agriculture on ecosystems. This study is first to quantify the net climate change mitigation impact of cover crops including land-use effects. A systematic literature and data review was conducted to identify major drivers for climate benefits and costs of cover crops in maize (Zea maize L.) production systems. The results indicate that cover crops lead to a net climate change mitigation impact (NCCMI) of 3.30 Mg CO2e ha-1 a-1. We created four scenarios with different impact weights of the drivers and all of them showing a positive NCCMI. Carbon land benefit, the carbon opportunity costs based on maize yield gains following cover crops, is the major contributor to the NCCMI (34.5% of all benefits). Carbon sequestration is the second largest contributor (33.8%). The climate costs of cover crops are mainly dominated by emissions from their seed production and foregone benefits due to land use for cover crops seeds. However, these two costs account for only 15.8% of the benefits. Extrapolating these results, planting cover crops before all maize acreage in the EU results in a climate change mitigation of 49.80 million Mg CO2e a-1, which is equivalent to 13.0% of the EU's agricultural emissions. This study highlights the importance of incorporating cover crops into sustainable cropping systems to minimize the agricultural impact to climate change.


Assuntos
Agricultura , Sequestro de Carbono , Mudança Climática , Produtos Agrícolas , Ecossistema , Zea mays , Produtos Agrícolas/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento , Agricultura/métodos , Agricultura/economia , Dióxido de Carbono/análise , Dióxido de Carbono/metabolismo
6.
Hum Vaccin Immunother ; 20(1): 2335722, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38698759

RESUMO

We provide estimates for (I) annual herpes zoster (HZ) cases, (II) carbon costs related to healthcare utilization, and (III) annual carbon emissions due to HZ among ≥50 years of age (YOA) United States (US) population. We estimated the annual number of HZ cases in the US based on available incidence data and demographic data of individuals ≥50 YOA. Both the healthcare resource utilization (HCRU) associated with HZ cases and the unit carbon dioxide equivalent (i.e. CO2e) costs associated with each type of HCRU in the US were estimated based on literature and studies available online. The carbon footprint associated with HZ annually among US adults ≥50 YOA was estimated by multiplying the unit carbon estimates by the HCRU. In the US population aged ≥50 YOA in 2020 (i.e. approximately 118 million), approximately 1.1 million cases of HZ occur annually assuming no vaccination. Based on 2 sources of HCRU the average kgCO2e per HZ patient ranged from 61.0 to 97.6 kgCO2e, with values by age group ranging from 40.9 kgCO2e in patients aged 50-59 to 195.9 kgCO2e in patients ≥80 YOA. The total annual HZ associated carbon ranged between 67,000 and 107,000 tons of CO2e in the US population aged ≥50 YOA. The impact of HZ on carbon footprint in the US results in considerable greenhouse gas (GHG)emissions. Assuming no vaccination, the burden of HZ is projected to rise over the coming years with the aging populations consequently worsening its impact on GHG emissions. (Figure 1).


Assuntos
Pegada de Carbono , Herpes Zoster , Humanos , Herpes Zoster/epidemiologia , Estados Unidos/epidemiologia , Idoso , Pegada de Carbono/estatística & dados numéricos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Masculino , Feminino , Incidência , Dióxido de Carbono/análise
7.
Crit Care ; 28(1): 146, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38693569

RESUMO

PURPOSE: A systematic review and meta-analysis to evaluate the impact of extracorporeal carbon dioxide removal (ECCO2R) on gas exchange and respiratory settings in critically ill adults with respiratory failure. METHODS: We conducted a comprehensive database search, including observational studies and randomized controlled trials (RCTs) from January 2000 to March 2022, targeting adult ICU patients undergoing ECCO2R. Primary outcomes were changes in gas exchange and ventilator settings 24 h after ECCO2R initiation, estimated as mean of differences, or proportions for adverse events (AEs); with subgroup analyses for disease indication and technology. Across RCTs, we assessed mortality, length of stay, ventilation days, and AEs as mean differences or odds ratios. RESULTS: A total of 49 studies encompassing 1672 patients were included. ECCO2R was associated with a significant decrease in PaCO2, plateau pressure, and tidal volume and an increase in pH across all patient groups, at an overall 19% adverse event rate. In ARDS and lung transplant patients, the PaO2/FiO2 ratio increased significantly while ventilator settings were variable. "Higher extraction" systems reduced PaCO2 and respiratory rate more efficiently. The three available RCTs did not demonstrate an effect on mortality, but a significantly longer ICU and hospital stay associated with ECCO2R. CONCLUSIONS: ECCO2R effectively reduces PaCO2 and acidosis allowing for less invasive ventilation. "Higher extraction" systems may be more efficient to achieve this goal. However, as RCTs have not shown a mortality benefit but increase AEs, ECCO2R's effects on clinical outcome remain unclear. Future studies should target patient groups that may benefit from ECCO2R. PROSPERO Registration No: CRD 42020154110 (on January 24, 2021).


Assuntos
Dióxido de Carbono , Humanos , Dióxido de Carbono/análise , Dióxido de Carbono/sangue , Troca Gasosa Pulmonar/fisiologia , Respiração Artificial/métodos , Insuficiência Respiratória/terapia
8.
Proc Natl Acad Sci U S A ; 121(21): e2316497121, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38739807

RESUMO

Decreased production of crops due to climate change has been predicted scientifically. While climate-resilient crops are necessary to ensure food security and support sustainable agriculture, predicting crop growth under future global warming is challenging. Therefore, we aimed to assess the impact of realistic global warming conditions on rice cultivation. We developed a crop evaluation platform, the agro-environment (AE) emulator, which generates diverse environments by implementing the complexity of natural environmental fluctuations in customized, fully artificial lighting growth chambers. We confirmed that the environmental responsiveness of rice obtained in the fluctuation of artificial environments is similar to those exhibited in natural environments by validating our AE emulator using publicly available meteorological data from multiple years at the same location and multiple locations in the same year. Based on the representative concentration pathway, real-time emulation of severe global warming unveiled dramatic advances in the rice life cycle, accompanied by a 35% decrease in grain yield and an 85% increase in quality deterioration, which is higher than the recently reported projections. The transcriptome dynamism showed that increasing temperature and CO2 concentrations synergistically changed the expression of various genes and strengthened the induction of flowering, heat stress adaptation, and CO2 response genes. The predicted severe global warming greatly alters rice environmental adaptability and negatively impacts rice production. Our findings offer innovative applications of artificial environments and insights for enhancing varietal potential and cultivation methods in the future.


Assuntos
Aquecimento Global , Oryza , Oryza/crescimento & desenvolvimento , Oryza/genética , Mudança Climática , Produtos Agrícolas/crescimento & desenvolvimento , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análise , Agricultura/métodos , Regulação da Expressão Gênica de Plantas , Temperatura , Transcriptoma
9.
Environ Sci Technol ; 58(19): 8299-8312, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38690832

RESUMO

Accurate estimates of fossil fuel CO2 (FFCO2) emissions are of great importance for climate prediction and mitigation regulations but remain a significant challenge for accounting methods relying on economic statistics and emission factors. In this study, we employed a regional data assimilation framework to assimilate in situ NO2 observations, allowing us to combine observation-constrained NOx emissions coemitted with FFCO2 and grid-specific CO2-to-NOx emission ratios to infer the daily FFCO2 emissions over China. The estimated national total for 2016 was 11.4 PgCO2·yr-1, with an uncertainty (1σ) of 1.5 PgCO2·yr-1 that accounted for errors associated with atmospheric transport, inversion framework parameters, and CO2-to-NOx emission ratios. Our findings indicated that widely used "bottom-up" emission inventories generally ignore numerous activity level statistics of FFCO2 related to energy industries and power plants in western China, whereas the inventories are significantly overestimated in developed regions and key urban areas owing to exaggerated emission factors and inexact spatial disaggregation. The optimized FFCO2 estimate exhibited more distinct seasonality with a significant increase in emissions in winter. These findings advance our understanding of the spatiotemporal regime of FFCO2 emissions in China.


Assuntos
Poluentes Atmosféricos , Dióxido de Carbono , Combustíveis Fósseis , China , Dióxido de Carbono/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental
10.
J Hazard Mater ; 471: 134294, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38669928

RESUMO

Biodegradable plastics promise eco-friendliness, yet their transformation into microplastics (bio-MPs) raises environmental alarms. However, how those bio-MPs affect the greenhouse gases (GHGs) and volatile organic compounds (VOCs) in soil ecosystems remains largely unexplored. Here, we investigated the effects of diverse bio-MPs (PBAT, PBS, and PLA) on GHGs and VOCs emission in typical paddy or upland soils. We monitored the carbon dioxide (CO2) and methane (CH4) fluxes in-situ using the self-developed portable optical gas sensor and analyzed VOC profiles using a proton-transfer reaction mass spectrometer (PTR-MS). Our study has revealed that, despite their biodegradable nature, bio-MPs do not always promote soil GHG emissions as previously thought. Specifically, PBAT and PLA significantly increased CO2 and CH4 emissions up to 1.9-7.5 and 115.9-178.5 fold, respectively, compared to the control group. While PBS exhibited the opposite trend, causing a decrease of up to 39.9% for CO2 and up to 39.9% for CH4. In addition, different types of bio-MPs triggered distinct soil VOC emission patterns. According to the Mann-Whitney U-test and Partial Least Squares Discriminant Analysis (PLS-DA), a recognizable VOC pattern associated with different bio-MPs was revealed. This study claims the necessity of considering polymer-specific responses when assessing the environmental impact of Bio-MPs, and providing insights into their implications for climate change.


Assuntos
Dióxido de Carbono , Metano , Microplásticos , Compostos Orgânicos Voláteis , Dióxido de Carbono/análise , Compostos Orgânicos Voláteis/análise , Metano/análise , Microplásticos/análise , Solo/química , Ecossistema , Poluentes do Solo/análise , Gases de Efeito Estufa/análise , Monitoramento Ambiental , Biodegradação Ambiental , Poluentes Atmosféricos/análise
11.
Curr Environ Health Rep ; 11(2): 225-237, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38600409

RESUMO

PURPOSE OF REVIEW: To describe the role of health equity in the context of carbon capture, utilization, and sequestration (CCUS) technologies. RECENT FINDINGS: CCUS technologies have the potential to both improve and worsen health equity. They could help reduce greenhouse gas emissions, a major contributor to climate change, but they could also have negative health impacts like air and noise pollution. More research is needed to fully understand the health equity implications of CCUS technologies. CCUS technologies have both health equity risks and benefits. Implementing misguided CCUS projects in vulnerable communities could exacerbate environmental injustice and health disparities and have the potential to increase carbon emissions. However, well-conceived projects could benefit communities through economic development. Governments, industry, and society should prioritize and expedite the reduction of CO2 emissions before considering carbon reductions via CCUS. Furthermore, CCUS projects must be thoroughly evaluated and should only proceed if they have demonstrated a net reduction in CO2 emissions and provide more benefits than risks to local communities. This underscores the importance of prioritizing health equity in the planning of CCUS projects.


Assuntos
Sequestro de Carbono , Equidade em Saúde , Humanos , Mudança Climática , Poluição do Ar/prevenção & controle , Dióxido de Carbono/análise , Gases de Efeito Estufa/análise
12.
Mar Pollut Bull ; 202: 116329, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38581735

RESUMO

This study investigates AIS data from March 2019 to February 2020 in Shanghai Port waters. The ship activities of berthing, waiting, and ingress/egress are extracted in detail to elucidate the emission characteristics of ships in Shanghai Port, differentiating emissions patterns across various ship activity. The findings reveal that the top three pollutants within Shanghai Port are CO2, NOX, and SO2. Container ships have the highest emissions, followed by bulk carriers. Berthed container ships and oil tankers exhibit the highest emission. Waiting container ships emit the most, followed by oil tankers and bulk carriers. Among ships entering and leaving the port, low-speed navigation produces the most emissions, followed by maneuvering and steady-speed navigation. Emission hotspots include the Yangtze River Estuary Anchorage and the main navigation channel into and out of the port. This study offers robust data support for an in-depth understanding and evaluation of ship emission characteristics in Shanghai Port.


Assuntos
Monitoramento Ambiental , Navios , China , Poluentes Atmosféricos/análise , Dióxido de Carbono/análise , Dióxido de Enxofre/análise
13.
Sci Total Environ ; 929: 172439, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621540

RESUMO

Biochar and soil carbon sequestration hold promise in mitigating global warming by storing carbon in the soil. However, the interaction between biochar properties, soil carbon-nitrogen cycling, and nitrogen fertilizer application's impact on soil carbon-nitrogen balance remained unclear. Herein, we conducted batch experiments to study the effects and mechanisms of rice straw biochar application (produced at 300, 500, and 700 °C) on net greenhouse gas emissions (CO2, N2O, CH4) in upland soils under different forms of nitrogen fertilizers. The findings revealed that (NH4)2SO4 and urea significantly elevated soil carbon dioxide equivalent emissions, ranging from 28 to 61.7 kg CO2e/ha and 8.2 to 37.7 kg CO2e/ha, respectively. Conversely, KNO3 reduced soil CO2e emissions, ranging from 2.2 to 13.6 kg CO2e/ha. However, none of these three nitrogen forms exhibited a significant effect on CH4 emissions. The pyrolysis temperature of biochar was found negatively correlated with soil CO2 and N2O emissions. The alkaline substances presented in biochar pyrolyzed at 500-700 °C raised soil pH, increased the ratio of Gram-negative to Gram-positive bacteria, and enhanced the relative abundance of Sphingomonadaceae. Moreover, the co-application of KNO3 based nitrogen fertilizer and biochar increased the total carbon/inorganic nitrogen ratio and reduces the relative abundance of Nitrospirae. This series of reactions led to a significant increase in soil DOC content, meanwhile reduced soil CO2 emissions, and inhibited the nitrification process and decreased the emission of soil N2O. This study provided a scientific basis for the rational application of biochar in soil.


Assuntos
Dióxido de Carbono , Carvão Vegetal , Fertilizantes , Nitrogênio , Óxido Nitroso , Solo , Carvão Vegetal/química , Fertilizantes/análise , Solo/química , Óxido Nitroso/análise , Nitrogênio/análise , Dióxido de Carbono/análise , Poluentes Atmosféricos/análise , Gases de Efeito Estufa/análise , Agricultura/métodos
14.
Sci Total Environ ; 927: 172272, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38583626

RESUMO

To combat with climate change, most countries have set carbon neutrality target. However, our understanding on carbon removal, release and sequestration by mariculture remains unclear. Here, carbon removal, release and sequestration by maricultured seaweeds, shellfish and fish in Shandong Province during 2003-2022 were assessed using a comprehensive method that considers the processes of biological metabolism, seawater chemistry and carbon footprint. Saccharina japonica productivity has been largely enhanced since 2014, resulting in increased production and CO2 removal and sequestration. Seaweeds removed 172 Gg C and sequestered 62 Gg C in 2022. CO2 removal and release by shellfish demonstrated a slow increase trend, ranging from 231 to 374 Gg C yr-1 and 897 to 1438 Gg C yr-1 during 2003-2022, respectively. Contrary to seaweed and shellfish, maricultured fish added CO2 to seawater due to the use of feeds. The added CO2 by fish culture achieved the peak of 60 Gg C in 2011 and decreased to 25 Gg C in 2022. Most of this added CO2 was released to atmosphere by microbial mineralization and it was in the range of 21-52 Gg C yr-1 during 2003-2022. After summing up the contribution of seaweeds, shellfish and fish, both total CO2 removal (from 110 to 259 Gg C yr-1) and total CO2 release (from 929 to 1429 Gg C yr-1) increased remarkably during the past 20 years. To neutralize CO2 release by shellfish and fish, Pyropia yezoensis needs the largest culture area (1.65 ± 0.15 × 106 ha) while Gracilariopsis lemaneiformis requires the smallest area (0.11 ± 0.03 × 106 ha). In addition, there are enough available areas for culturing G. lemaneiformis, Ulva prolifera and Sargassum fusifarme to neutralize total CO2 emission in Shandong Province. This study elucidates carbon removal, release and sequestration capacities of mariculture and indicates that seaweed culture has a tremendous potential to achieve carbon neutrality target in Shandong.


Assuntos
Aquicultura , Sequestro de Carbono , China , Alga Marinha/metabolismo , Dióxido de Carbono/análise , Mudança Climática , Água do Mar/química , Animais , Carbono/metabolismo , Carbono/análise , Frutos do Mar , Peixes/metabolismo , Monitoramento Ambiental
15.
Mar Pollut Bull ; 202: 116289, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38564822

RESUMO

Seaweeds are ecosystem engineers that can serve as habitat, sequester carbon, buffer ecosystems against acidification, and, in an aquaculture setting, represent an important food source. One health issue regarding the consumption of seaweeds and specifically, kelp, is the accumulation of some trace elements of concern within tissues. As atmospheric CO2 concentrations rise, and global oceans acidify, the concentrations of elements in seawater and kelp may change. Here, we cultivated the sugar kelp, Saccharina latissima under ambient (~400 µatm) and elevated pCO2 (600-2400 µatm) conditions and examined the accumulation of trace elements using x-ray powder diffraction, sub-micron resolution x-ray imaging, and inductively coupled plasma mass spectrometry. Exposure of S. latissima to higher concentrations of pCO2 and lower pH caused a significant increase (p < 0.05) in the iodine and arsenic content of kelp along with increased subcellular heterogeneity of these two elements as well as bromine. The iodine-to­calcium and bromine-to­calcium ratios of kelp also increased significantly under high CO2/low pH (p < 0.05). In contrast, high CO2/low pH significantly reduced levels of copper and cadmium in kelp tissue (p < 0.05) and there were significant inverse correlations between concentrations of pCO2 and concentrations of cadmium and copper in kelp (p < 0.05). Changes in copper and cadmium levels in kelp were counter to expected changes in their free ionic concentrations in seawater, suggesting that the influence of low pH on algal physiology was an important control on the elemental content of kelp. Collectively, these findings reveal the complex effects of ocean acidification on the elemental composition of seaweeds and indicate that the elemental content of seaweeds used as food must be carefully monitored as climate change accelerates this century.


Assuntos
Dióxido de Carbono , Algas Comestíveis , Kelp , Laminaria , Água do Mar , Oligoelementos , Kelp/química , Oligoelementos/análise , Água do Mar/química , Concentração de Íons de Hidrogênio , Dióxido de Carbono/análise , Oceanos e Mares , Poluentes Químicos da Água/análise , Acidificação dos Oceanos
16.
Sci Total Environ ; 928: 172452, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38615757

RESUMO

Greenhouse gas (GHG) fluxes from peatland soils are relatively well studied, whereas tree stem fluxes have received far less attention. Simultaneous year-long measurements of soil and tree stem GHG fluxes in northern peatland forests are scarce, as previous studies have primarily focused on the growing season. We determined the seasonal dynamics of tree stem and soil CH4, N2O and CO2 fluxes in a hemiboreal drained peatland forest. Gas samples for flux calculations were manually collected from chambers at different heights on Downy Birch (Betula pubescens) and Norway Spruce (Picea abies) trees (November 2020-December 2021) and analysed using gas chromatography. Environmental parameters were measured simultaneously with fluxes and xylem sap flow was recorded during the growing season. Birch stems played a greater role in the annual GHG dynamics than spruce stems. Birch stems were net annual CH4, N2O and CO2 sources, while spruce stems constituted a CH4 and CO2 source but a N2O sink. Soil was a net CO2 and N2O source, but a sink of CH4. Temporal dynamics of stem CH4 and N2O fluxes were driven by isolated emissions' peaks that contributed significantly to net annual fluxes. Stem CO2 efflux followed a seasonal trend coinciding with tree growth phenology. Stem CH4 dynamics were significantly affected by the changes between wetter and drier periods, while N2O was more influenced by short-term changes in soil hydrologic conditions. We showed that CH4 emitted from tree stems during the wetter period can offset nearly half of the soil sink capacity. We presented for the first time the relationship between tree stem GHG fluxes and sap flow in a peatland forest. The net CH4 flux was likely an aggregate of soil-derived and stem-produced CH4. A dominating soil source was more evident for stem N2O fluxes.


Assuntos
Betula , Monitoramento Ambiental , Florestas , Gases de Efeito Estufa , Metano , Solo , Gases de Efeito Estufa/análise , Solo/química , Metano/análise , Estações do Ano , Dióxido de Carbono/análise , Óxido Nitroso/análise , Picea , Caules de Planta , Poluentes Atmosféricos/análise
17.
PLoS One ; 19(4): e0296787, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635585

RESUMO

In the context of green and sustainable development and rural revitalization, analysis of the relationship between economic development and the evolution of carbon metabolism is of great significance for China's future transformation of development models. This study analyzed the spatial characteristics and spatiotemporal evolution pattern of the decoupling status between carbon metabolism and economic development of Laiwu during two periods from 2001 to 2018 at the village and town unit scales by using the Tapio decoupling model. The results showed that the growth rate of carbon metabolism from 2001 to 2009 was significantly higher than that from 2009 to 2018. The spatial heterogeneity of the decoupling states between economic development and carbon metabolism from 2009 to 2018 was significantly stronger than that from 2001 to 2009 in two units. From 2001 to 2018, the development trend gradually trended towards spatial imbalance. The decoupling status between villages and towns had a high degree of consistency from 2001 to 2009 and inconsistency from 2009 to 2018. From 2001 to 2009, the decoupling status of about 78% of villages was consistent with that of towns. Moreover, from 2009 to 2018, the consistency reduced to 32.2%, and the decoupling status of about 48% of villages was weaker than that of towns. According to the reclassification results of different decoupling state change types, from 2001 to 2018, about 52.2% of the villages had a decoupling state evolution type of eco-deteriorated economic development, which is an unsatisfactory development trend in a short time. Moreover, about 12.1% of the villages had a decoupling state evolution type of eco-improved economic development, which is a satisfactory development trend.


Assuntos
Carbono , Desenvolvimento Econômico , Humanos , Cidades , Carbono/análise , População Rural , China , Dióxido de Carbono/análise
18.
PLoS One ; 19(4): e0292260, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635691

RESUMO

Pollution in the environment is today the biggest issue facing the globe and the main factor in the development of many fatal diseases. The main objective of the study to investigate green investments, economic growth and financial development on environmental pollution in the G-7 countries. This study used annual penal data from 1997 to 2021. The panel NARDL (Non-linear autoregressive distributed lag) results affirm that the positive change of green investment and negative shock in green investment have a significant and positive association with environment pollution in G-7 nations. Our findings provide more evidence for the long-term asymmetry between financial development and environmental performance. However, the findings confirm that a positive modification in financial development has a positive and significant effect on environment pollution. Whereas negative shock in financial development is negative and insignificant relationship with environment pollution. Moreover, the outcomes of the study reveal that both positive shock in gross domestic product growth and negative shock of economic growth have a significant and positive link with environment pollution in G-7 countries. According to the findings, by lowering carbon dioxide emissions, green investments reduced environmental pollution in the G-7 nations over the long and short term. Moreover, it is an innovative research effort that provides light on the connection between green investments, financial development, and the environment while making mention to the EKC in G-7 countries. After all these, our recommendation is to increases green investment expenditures to reduce environmental pollution in the G-7 nations based on our findings. Additionally, one important way for the nation to achieve its sustainable development goals is to improve advancements in the financial sector.


Assuntos
Poluição Ambiental , Desenvolvimento Sustentável , Poluição Ambiental/análise , Investimentos em Saúde , Dióxido de Carbono/análise , Desenvolvimento Econômico
19.
Methods Mol Biol ; 2790: 63-76, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38649566

RESUMO

Stomata can be distributed exclusively on the abaxial or adaxial leaf surface, but they are most commonly found on both leaf surfaces. Variations in stomatal arrangement, patterning, and the impact on photosynthesis can be measured using an infrared gas exchange system. However, when using standard gas exchange techniques, both surfaces are measured together and averaged to provide leaf-level values. Employing an innovative gas exchange apparatus with two infrared gas analyzers, separate gaseous flux from both leaf surfaces can be quantified simultaneously and independently. Here, we provide examples of typical measurements that can be performed using a "split chamber" gas exchange system.


Assuntos
Fotossíntese , Estômatos de Plantas , Estômatos de Plantas/metabolismo , Estômatos de Plantas/fisiologia , Gases/química , Folhas de Planta/metabolismo , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análise , Dióxido de Carbono/química
20.
Methods Mol Biol ; 2790: 95-120, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38649568

RESUMO

The recent development of an infrared gas analyzer capable of making carbon dioxide flux measurements from aquatic samples has enabled a new sphere of photosynthesis research. This study details key photosynthesis measurements on four aquatic and hydrophytic species, diverse in their morphology, physiology, and habitat. This guide specifies the methods and procedures needed to make reliable and accurate gas exchange measurements, with examples of data correction and presentation.


Assuntos
Dióxido de Carbono , Carbono , Fotossíntese , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análise , Carbono/metabolismo , Organismos Aquáticos/metabolismo , Ecossistema
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