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1.
Water Environ Res ; 96(10): e11131, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39327691

RESUMO

This study aims to investigate the response mechanisms of groundwater microbial-toxicological indicators, specifically total bacteria count (TBC) and total coliform count (TCC), to water quality indicators and environmental conditions. Using data from a water source in the western plateau of China, a predictive model focusing on TBC and TCC was developed. An orthogonal experimental design was employed to manipulate environmental conditions such as temperature, pH, and porosity, facilitating laboratory experiments. These experiments measured pH, chemical oxygen demand (COD), oxidation-reduction potential (ORP), TBC, and TCC at varying depths and environmental conditions. Principal component analysis elucidated the mechanisms by which water quality indicators and environmental conditions affect groundwater microbial-toxicological indicators. A prediction model for these indicators in plateau regions was established based on a backpropagation neural network (BP-NN), using TBC and TCC as target variables and the newly extracted principal components as influencing factors. The results demonstrate that environmental conditions and water quality indicators primarily influence the evolution of groundwater microbial-toxicological indicators by altering the ionic charge quantities, redox conditions, and temperature of the groundwater. The predictive model for groundwater microbial-toxicological indicators shows trends consistent with experimental outcomes, with an average relative error of less than 15%, meeting engineering requirements. PRACTITIONER POINTS: The values of total bacteria count (TBC) and total coliform count (TCC) under different conditions were obtained by column experiments. The influence mechanism of environmental conditions and groundwater indicators on TBC and TCC was elaborated by principal component analysis. TBC and TCC prediction models were established through the investigation of water sources in a plateau area and laboratory experiments.


Assuntos
Água Subterrânea , Água Subterrânea/microbiologia , Microbiologia da Água , Qualidade da Água , Monitoramento Ambiental/métodos , Enterobacteriaceae/isolamento & purificação , China
2.
Environ Manage ; 74(4): 715-728, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39033246

RESUMO

The impacts of landscape patterns on river water quality are commonly acknowledged, but understanding the complex processes by which landscape patterns affect water quality is still limited, especially in densely populated urban areas. Exploring the mechanisms through which landscape characteristics influence water quality changes in urbanized rivers will benefit regional water resource protection and landscape-scale resource development and utilization. Utilizing daily water quality monitoring data from rivers in the urbanized area of the Pearl River Delta in 2020, our research employed canonical analysis and partial least squares structural equation modeling (PLS-SEM) to explore the processes and mechanisms of the influence of urbanized river landscape patterns on surface water quality. The results indicated that total nitrogen (TN) was the critical indicator limiting the water quality of rivers in the Pearl River Delta. The landscape composition and configuration indexes exhibited non-linear variations with scale, and the landscape fragmentation was higher closer to the river. Landscape patterns had the most significant influence on water quality under the characteristic scale of a 5.50 km circular buffer zone, and landscape composition dominated the change of water quality of urbanized rivers, among which 30.64% of the percentage patch area of construction (C_PLAND) contributed 46.40% to the explanation rate of water quality change, which was the key landscape index affecting water quality. Moreover, landscape patterns had a higher interpretive rate of 39.29% on water quality in the wet season compared to 36.62% in the dry season. Landscape composition had an indirect negative impact on water quality, with a value of 0.47, by affecting the processes of runoff and nutrient migration driven by human activities, while landscape configuration had an indirect negative impact on water quality, with a value of 0.11. Our research quantified the impacts of landscape patterns driven by human activities on surface water quality and proposed management measures to optimize the allocation of landscape resources in riparian zones of urbanized rivers. The results provide a scientific basis for water quality management and protection in urbanized rivers.


Assuntos
Monitoramento Ambiental , Rios , Urbanização , Qualidade da Água , Rios/química , China , Monitoramento Ambiental/métodos , Nitrogênio/análise
3.
J Environ Manage ; 362: 121222, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38833928

RESUMO

The carbon generalized system of preferences (CGSP) is an innovative incentive mechanism implemented by the Chinese government, which has also become an important part of carbon emission reduction at the living end, and it is of great significance to study whether the Pilot Policy can reduce the carbon emissions of residents. This study firstly accounts for the total carbon emissions and per capita carbon emissions of the residents of 284 cities in China, and on this basis, adopts the SCM method to quantitatively study and analyze the overall and local implementation effects of CGSP in China by taking the first batch of CGSP pilots in China as an example, and further applies the mediation effect model to test the pathways of the role of CGSP. The main findings of the study are as follows: (1) During the period of 2010-2020, the total carbon emissions from urban residents' living in China showed a yearly growth trend, from 36,623.98 ×10-2Mt in 2010-85,241.20 ×10-2Mt in 2020, an increase of 8.83%. Total carbon emissions present a structural difference of "electricity consumption > central heating > private transport > gas (oil, natural gas) consumption". (2) Overall, the implementation of the CGSP had a robust positive impact on the overall carbon emission reduction in the pilot cities, with an average annual emission reduction effect value of 36.53 ×10-2Mt. Locally, the annual net policy effect values of Dongguan, Zhongshan, Heyuan, and Guangzhou are 6169.79 ×10-2, 26,600.17 ×10-2, 17,081.34 ×10-2 and 9393.36 ×10-2Mt respectively. (3) CGSP has a good carbon emission reduction effect by suppressing the impact on residents' carbon emissions through enhancing the city's innovation capacity and promoting electricity saving and consumption reduction, while the mediating effect played by the promotion of green and low-carbon travel in the pilot policy is not significant. Finally, based on the research findings, relevant suggestions are targeted.


Assuntos
Carbono , Cidades , China , Humanos , Poluição do Ar/prevenção & controle , Dióxido de Carbono/análise
4.
Sci Rep ; 14(1): 11310, 2024 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760375

RESUMO

Seeds, as the initial products in agricultural systems, play a pivotal role in ensuring quality, fundamental to national food security and sustainable agricultural development. This study introduces a concept integrating public governance and evolutionary game theory to construct a quadripartite evolutionary game model involving seed companies, certification agencies, farmers, and governmental departments. It considers the strategic choices of these stakeholders under varying economic motivations and market mechanisms, as well as the influence of external regulation and incentives on game strategies. The existence conditions for evolutionarily stable strategy combinations are determined using the Lyapunov first method, and MATLAB is employed for numerical simulation analysis to validate the game analysis under initial conditions. The simulation results reveal two potential equilibrium points corresponding to different strategic choices among stakeholders. The study finds that producing high-quality seeds and the refusal of certification agencies to engage in rent-seeking are crucial for ensuring seed quality. Additionally, the cost-benefit ratio of seed companies, the speculative cost of certification agencies, and the rights-protection cost of farmers are key determinants in the evolution of seed quality assurance strategies. This research also holds practical significance in enhancing seed quality assurance mechanisms and fostering sustainable development in agriculture.


Assuntos
Agricultura , Sementes , Agricultura/métodos , Teoria dos Jogos , Humanos
5.
Philos Trans R Soc Lond B Biol Sci ; 379(1902): 20230323, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38583467

RESUMO

Monitoring the extent to which invasive alien species (IAS) negatively impact the environment is crucial for understanding and mitigating biological invasions. Indeed, such information is vital for achieving Target 6 of the Kunming-Montreal Global Biodiversity Framework. However, to-date indicators for tracking the environmental impacts of IAS have been either lacking or insufficient. Capitalizing on advances in data availability and impact assessment protocols, we developed environmental impact indicators to track realized and potential impacts of IAS. We also developed an information status indicator to assess the adequacy of the data underlying the impact indicators. We used data on 75 naturalized amphibians from 82 countries to demonstrate the indicators at a global scale. The information status indicator shows variation in the reliability of the data and highlights areas where absence of impact should be interpreted with caution. Impact indicators show that growth in potential impacts are dominated by predatory species, while potential impacts from both predation and disease transmission are distributed worldwide. Using open access data, the indicators are reproducible and adaptable across scales and taxa and can be used to assess global trends and distributions of IAS, assisting authorities in prioritizing control efforts and identifying areas at risk of future invasions. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'.


Assuntos
Biodiversidade , Espécies Introduzidas , Animais , Reprodutibilidade dos Testes , Anfíbios , Ecossistema
6.
Front Microbiol ; 15: 1397683, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650885

RESUMO

Freshwater wetlands are the wetland ecosystems surrounded by freshwater, which are at the interface of terrestrial and freshwater ecosystems, and are rich in ecological composition and function. Biodiversity in freshwater wetlands plays a key role in maintaining the stability of their habitat functions. Due to anthropogenic interference and global change, the biodiversity of freshwater wetlands decreases, which in turn destroys the habitat function of freshwater wetlands and leads to serious degradation of wetlands. An in-depth understanding of the effects of biodiversity on the stability of habitat function and its regulation in freshwater wetlands is crucial for wetland conservation. Therefore, this paper reviews the environmental drivers of habitat function stability in freshwater wetlands, explores the effects of plant diversity and microbial diversity on habitat function stability, reveals the impacts and mechanisms of habitat changes on biodiversity, and further proposes an outlook for freshwater wetland research. This paper provides an important reference for freshwater wetland conservation and its habitat function enhancement.

7.
Environ Sci Pollut Res Int ; 31(4): 5699-5715, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38123778

RESUMO

Existing studies on urbanization and carbon emissions are mostly based on a single pathway and lack the support of a theoretical framework. This study innovatively integrates Grossman's perspective of environmental effects analysis to develop a new framework to interpret the mechanism of multidimensional urbanization (MU) and carbon emissions (CEs). We first explored the spatial effects of MUs and CEs in the Yangtze River Delta urban agglomeration (YRDUA) and then introduced the "population-land-economic" urbanization variables into the S-STIRPAT model to determine the impact mechanisms of each factor on CEs under different urbanization dimensions. The results show that the spatiotemporal development patterns of MUs and CEs overlap to some extent. The Shanghai-Nanjing line is a high-value area of urbanization with different dimensions, as some edge cities are in low-value areas. However, there are local differences in the different dimensions of urbanization, e.g., population urbanization in the southern area is in a high-value area. CEs show a core-edge structure of "high in the center and low in the north and south". All factors, except for population urbanization, affect CEs locally, and their spillover effects are all positive, except for energy intensity, which has a negative influence on CEs in neighboring regions. Land urbanization has the largest positive impact on CEs, with a total effect coefficient of 0.409; economic urbanization has a coefficient of 0.195, and population urbanization has a coefficient of only 0.070. The findings can help to maximize urbanization growth while minimizing harmful environmental externalities.


Assuntos
Carbono , Urbanização , Carbono/análise , China , Cidades , Desenvolvimento Econômico , Rios
8.
Environ Sci Pollut Res Int ; 30(24): 66254-66273, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37097574

RESUMO

This study employed fixed effects (FE) models, difference-in-differences (DID) methods, and mediating effect (ME) models to explore the total effect, structural effect, heterogeneous characteristics, and impact mechanism of digital inclusive finance (DIF) on green technology innovation (GTI) from 2011 to 2020. We derived the following results. First, DIF can significantly improve the level of GTI, and the positive role of internet digital inclusive finance is greater than that of traditional banks, but the three dimensions of the DIF index have different impacts on such innovation. Second, the impact of DIF on GTI has a "siphon effect," which is significantly promoted in regions with stronger economic power and inhibited in those with weaker economic power. Finally, there is an influence mechanism of "digital inclusive finance → financing constraints → green technology innovation." Our findings provide evidence to establish a lasting effect mechanism for DIF to promote GTI, and they have important reference value for other countries to develop DIF.


Assuntos
Internet , Tecnologia , China , Valores de Referência , Desenvolvimento Econômico
9.
Environ Sci Pollut Res Int ; 29(59): 89132-89155, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35843972

RESUMO

This paper explores the impact of green credit (Cre) on low-carbon transition (Lct) and its influence mechanisms. Theoretically, Cre promotes environmentally induced R&D (ER&D), which in turn affects Lct. Empirically, using a panel data of 30 Chinese provinces and cities from 2004 to 2019, we measure the provincial ER&D and carbon emission performance (Cep), based on which we conduct an econometric analysis. It is observed that Cre promotes Lct (that is, Cre reduces carbon emission and improves Cep). This conclusion still holds after a series of robustness tests and endogeneity treatments. And the impact of Cre on Lct is asymmetrical due to regional differences in physical and geoclimatic characteristics, income levels, and financing constraint levels. Second, ER&D is an important mechanism of action for Cre enhancing Lct. Further analysis reveals that ER&D can affect Lct through energy transition effects and green innovation effects. Finally, the positive effect of Cre on ER&D is significant in high level of Lct regions, but insignificant in low level of Lct regions. Based on this, specific policy recommendations from the perspective of developing Cre and establishing an incentive mechanism for ER&D are put forward.


Assuntos
Dióxido de Carbono , Carbono , Carbono/análise , Cidades , Dióxido de Carbono/análise , China , Desenvolvimento Econômico
10.
Sci Med Footb ; 6(3): 331-339, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35311487

RESUMO

Soccer athletes experience repetitive head impacts (RHI) through purposeful heading and unintentional head impacts, which may be associated with acute and chronic brain injury. Previous soccer studies have sought to quantify and characterize RHI, but to-date no consistent, standardized methods exist. The Heads-Up Checklist (HUC), originally used for characterizing head impacts in hockey, was modified to be used in soccer (soccer HUC [SHUC]). Our aim was to determine the reliability of quantifying ball-to-head impacts using video verification and to develop and test the reliability of the SHUC to characterize RHI in soccer. Two trained reviewers used the SHUC to quantify ball-to-head impacts and characterize non-ball-to-head impacts in 38 male and female collegiate soccer matches. Intraclass correlation coefficient (ICC) and Cohen's Kappa were used to assess interrater reliability. Independent t-tests and chi-square analyses were used to examine sex differences. The interrater reliability for quantifying ball-to-head impacts was excellent (ICC = 0.97); however, only half of the non-ball-to-head impact characteristics had acceptable interrater reliability with two reviewers. The number of ball-to-head-impacts and RHI characteristics were consistent between males and females (gggp > 0.05). Our results suggest that the SHUC is an applicable standardized method to quantify and characterize RHI from video footage of soccer matches; however, accurately characterizing some aspects of RHI is a challenging task that may be supplemented by head impact sensor data.


Assuntos
Concussão Encefálica , Hóquei , Futebol , Atletas , Feminino , Hóquei/lesões , Humanos , Masculino , Reprodutibilidade dos Testes , Futebol/lesões
11.
J Hazard Mater ; 424(Pt D): 127750, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34838359

RESUMO

Microplastics (MPs) are creating an emerging threat on the soil ecosystems and are of great global concern. However, the distribution in soil-plant system, as well as the phytotoxicity and impact mechanisms of MPs remain largely unexplored so far. This study introduced the diverse sources of MPs and showed the significant spatial variation in the global geographic distribution of MPs contamination based on data collected from 116 studies (1003 sampling sites). We systematically discussed MPs phytotoxicity, such as plant uptake and migration to stems and leaves, delaying seed germination, impeding plant growth, inhibiting photosynthesis, interfering with nutrient metabolism, causing oxidative damage, and producing genotoxicity. We further highlighted the alterations of soil structure and function by MPs, as well as their self and load toxicity, as potential mechanisms that threaten plants. Finally, this paper provided several preventive strategies to mitigate soil MPs pollution and presented research gaps in the biogeochemical behavior of MPs in soil-plant systems. Meanwhile, we recommended that methods for the quantitative detection of MPs accumulated in plant tissues should be explored and established as soon as possible. This review will improve the understanding of the environmental behavior of MPs in soil-plant systems and provide a theoretical reference to better assess the ecological risk of MPs.


Assuntos
Microplásticos , Poluentes do Solo , Ecossistema , Plásticos/toxicidade , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
12.
J Hazard Mater ; 343: 191-199, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-28950207

RESUMO

In this work, the impact of organic matter on the degradation of polycyclic aromatic hydrocarbons (PAHs) in textile dyeing sludge by ultrasound-Fenton process has been studied. Sludge organic matter (SOM) was characterized and the degradation efficiencies of PAHs at various oxidation intensities (Fenton's reagent of 20, 70, and 140mmol/L, ultrasonic densities of 0.36, 0.90, and 1.80W/cm3, and reaction time of 15, 25, and 40min) were determined. The results showed that 75.52-84.40% of PAHs and 16.32-31.13% of SOM had degraded after ultrasound-Fenton treatment, confirming the competitive relation between both of them for degradation. The aliphatic SOM fractions were preferentially oxidized owing to their easily degradable properties, while equimolar amounts of the aromatic moieties would require more oxidant compared to the aliphatic fractions. Correlation analysis demonstrated that SOM with its lower content, stronger polarity, and a higher proportion of labile organic fraction was more favourable for PAHs degradation. In addition, the SOM fractions were decomposed to biodegradable matter after treatment, which further enhance the biodegradability of sludge. This study provides insights into the role of SOM in PAHs removal by AOPs, and confirms that the ultrasound-Fenton treatment could not only effectively degrade PAHs, but also modify SOM.


Assuntos
Peróxido de Hidrogênio/química , Ferro/química , Hidrocarbonetos Policíclicos Aromáticos/química , Ondas Ultrassônicas , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Corantes , Resíduos Industriais , Esgotos , Têxteis
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