Phytotoxicity and uptake of chlorpyrifos in cabbage

Chinese cabbage, Brassica chinensis L., and cabbage, Brassica oleracea L. var. capitata, are the main daily foliar vegetables of the vast majority of the population of eastern and southern China. Cabbages are also planted and consumed widely in other countries. The insecticide and acaricide chlorpyrifos is registered in many countries. Chlorpyrifos controls a variety of insects in plants and soils, and chlorpyrifos is extensively used in the Chinese market. Food poisoning due to the presence of organophosphorus pesticide residues in vegetables has been reported in China provinces. Plant uptake of pesticide residues in air, water, and soil is a source of pesticide residues in vegetables. Here, phytotoxicity and uptake of chlorpyrifos by Chinese cabbage and cabbage were studied in the laboratory using the batch technique. From 0 to 16 days after chlorpyrifos treatment, vegetables roots, stems, leaves, and culture water samples were collected, and the residues of chlorpyrifos in culture water, plant tissues were analyzed using GC-FPD. The results demonstrate that culture solutions with chlorpyrifos had no significant inhibitory effects on vegetable plant height. However, at 1.0 mg/l, it had significant inhibitory effects on the root length and fresh weight of Chinese cabbage. Then, at 10.0 mg/l, it had only significant inhibitory effects on the root length and fresh weight of cabbage compared to the control treatment. The disappearance rates of chlorpyrifos in solutions were in sequence as: nutrition solution with Chinese cabbage, nutrition solution with cabbage, pond water, nutrition solution. The results showed also that chlorpyrifos can be taken up by roots of Chinese cabbage and cabbage from water and subsequently translocated as a function of time. Uptake dynamics of chlorpyrifos from culture solutions by the two cabbage plants were similar.     

The explosion overpressure field and flame propagation of methane/air and methane/coal dust/air mixtures

The explosion of the methane/air mixture and the methane/coal dust/air mixture under 40 J center spark ignition condition was experimentally studied in a large-scale system of 10 m³ vessel. Five pressure sensors were arranged in space with different distances from the ignition point. A high-speed camera system was used to record the growth of the flame. The maximum overpressure of the methane/air mixture appeared at 0.75 m away from the ignition point; the thickness of the flame was about 10 mm and the propagation speed of the flame fluctuated around 2.5 m/s with the methane concentration of 9.5%. The maximum overpressure of the methane/coal dust/air mixture appeared at 0.5 m. The flame had a structure of three concentric zones from outside were the red zone, the yellow illuminating zone and the bright white illuminating zone respectively; the thickness and the propagation speed of the flame increased gradually, the thickness of red zone and yellow illuminating zone reached 3.5 cm and 1 cm, the speed reached 9.2 m/s at 28 ms.     

WASP模型湖库水环境模拟国内外研究进展综述

WASP（The water quality analysis simulation program）模型是美国环保局（EPA）推荐使用的水质模型之一,数年来被广泛应用于各类水体的水质模拟、预测和决策制定.本文简述了WASP模型的基本原理,针对湖泊和水库较为相似的水环境特征,阐述了WASP模型在湖库水环境中应用的国内外进展,总结和分析了WASP模型的应用前景和不足之处,为进行湖库水环境模拟研究和模型的选用提供一定的参考依据.     

环境监测与环境监理之间关系研究

随着社会经济不断发展,环境破坏和污染问题愈演愈烈,全球环境恶化问题已对经济可持续发展形成阻碍作用,环境保护问题已提上全球人类长远发展进程中.环境保护工程作为实现经济可持续发展的最重要环节之一,其最主要改革内容为环境监测和环境监理,因此研究二者之间的关系成为环境保护工作中的重要课题.本文分析了环境监测和环境监理之间的联系,探讨了环境监测对环境监理促进意义的问题,并提出了可行性建议和措施.只有环境监测和环境监理工作协同发展,才能使中国经济与环境的可持续发展取得长足进步.     

油罐车导静电拖地带防静电效果研究

通过对油罐车对地泄放电阻值的检测,并对比导静电拖地带接地前后油罐车对地泄放的电阻值,研究不同情况下导静电拖地带对油罐车静电泄放的效果,探讨导静电带作为静电泄放途径存在的必要性。     

Classification technology of domestic waste from 2000 to 2019: a bibliometrics-based review

Environmental Science and Pollution Research - Waste classification is to reduce solid waste and its associated environmental pollution. This paper applied bibliometrics to assess publications...     

Potential ecological and health risk assessment of different kiwifruit orchards in Qianjiang district,Chongqing city,China

Environmental Science and Pollution Research - Heavy metal (HM) pollution in orchards is becoming serious in many countries, and some fruit HMs exceed the safety limits. In this study, contents of...     

Heterogeneous impacts of financial development on carbon emissions: evidence from China’s provincial data

The effect of financial development on carbon emissions is a hot topic. Although some researches study the heterogeneous impacts of financial development on carbon emissions at the country level, few paper has investigated their heterogeneous relations within the same country. This paper, applying geographically and temporally weighted regression (GTWR), studies the spatial–temporal heterogeneity of the impacts of financial development on carbon emissions across China’s 30 provinces from 2003 to 2017. The results show that financial development proxied by bank credit indicators curbs carbon emissions in most provinces most of the time, while that proxied by stock market indicator exhibits nonlinear relationships in most provinces, such as U-shaped, inverse U-shaped, and inverse N-shaped. The paper concludes first that financial development proxied by different indicators may exert varied impacts on carbon emissions. Second, the impact of financial development on carbon emissions shows great heterogeneity among different provinces and different years: it may be curbing or increasing, and even it is curbing, its curbing effects differ greatly across provinces and years. Third, the impact of financial development on CO2 is not always monotonic; instead, it may be nonlinear. Regional segmentation of financial markets may explain the heterogeneity. Some policy suggestions are also given.

     

Analysis of the influencing factors of atmospheric particulate matter accumulation on coniferous species: measurement methods,pollution level,and leaf traits

Environmental Science and Pollution Research - Urban trees, especially their leaves, have the potential to capture atmospheric particulate matter (PM) and improve air quality. However, the amount...