Comparisons of Measured and Modelled Ozone Deposition to Forests in Northern Europe

The performance of a new dry deposition module, developedfor the European-scale mapping and modelling of ozone flux to vegetation, was tested against micrometeorological ozone and water vapour flux measurements. The measurement data are for twoconiferous (Scots pine in Finland, Norway spruce in Denmark) and one deciduous forest (mountain birch in Finland). On average, themodel performs well for the Scots pine forest, if local inputdata are used. The daytime deposition rates are somewhat over-predicted at the Danish site, especially in the afternoon. The mountain birch data indicate that the generic parameterisationof stomatal responses is not very representative of this northernspecies. The module was also tested by using modelled meteorological data that constitute the input for a photochemical transport model.     

An on-line instrument for mobile measurements of the spatial variability of hexavalent and trivalent chromium in urban air

The Steam-Jet Aerosol Collector-long Pathlength Absorbance Spectroscopy (SJAC-LPAS), an on-line continuous instrument for mobile measurements of spatial distribution of water-soluble hexavalent and trivalent chromium in ambient aerosols, has been developed and is presented here. The system collects particles with the SJAC and analyzes the collected sample on-line using the diphenycarbazide (DPC) colorimetric method. By using a Teflon AF (Amorphous Fluoropolymer) liquid core wave guide, the limit of detection has been significantly improved, allowing on-line measurements at ambient concentrations. The limit of detection for Cr(VI) is 0.2 ng m⁻³. Water-soluble Cr(III) can also be measured by oxidizing it to Cr(VI) in a parallel line using hydrogen peroxide before the detection with the DPC method. The concentration of Cr(III) is then determined as the difference between the two lines (Cr(VI) and Cr(VI) plus Cr(III)). The instrument was specifically designed to be used on a mobile platform to study spatial distribution of the pollutant within a city on a scale of 100 m. Special attention was given to the time resolution and the stability of the instrument performance under driving conditions. The time resolution of the instrument is 15 s. At a typical driving speed of 30 km h⁻¹ the instrument can detect variations in chromium concentration (“hot spots”) on the scale of about 150 m. The instrument has proven to operate reliably and capture temporal and spatial variability of Cr(VI) concentration during four mobile measurement campaigns in Wilmington, DE.     

房地产开发项目的环境污染和防治措施

随着我国房地产事业的蓬勃发展 ,建设开发过程中的环境问题日益突出 ,如果防治措施不当 ,会对环境造成一定危害。根据房地产开发项目的污染特点 ,分别采取不同的防治措施后 ,可以实现项目开发和环境保护的双赢。     

资源环境领域脱钩分析研究进展

为掌握资源环境领域脱钩分析的研究进展,论文采用概括和比较分析的手段,从脱钩概念界定、脱钩分析的主要关注领域、脱钩分析的测度方法以及脱钩指标4个方面对资源环境领域的脱钩分析进行了梳理和概括。归纳出已有研究的几个特点:①不同研究对于脱钩的定义和类型划分不同,就脱钩而言,主要区别在于所包含绝对脱钩、相对脱钩和衰退性脱钩中的类型不同;②目前脱钩分析的研究领域主要集中在宏观层面以及部分行业(产业)层面的环境(资源)压力与其驱动因素之间的脱钩分析;③不同研究所采用的脱钩测度方法有很大差别,目前大致有8类不同的脱钩测度方法;④脱钩指标也是脱钩分析中的一项重要研究内容,目前还没有一个统一的指标体系,越来越多的研究将各类有关环境压力和资源消耗的指标应用到脱钩分析作为脱钩指标。最后探讨了还需要进一步深入研究的内容。     

First in situ UV profile across the UTLS accompanied by ozone measurement over the Tibetan Plateau

Ultraviolet radiation (UV) and ozone can greatly affect human health and the Earth's ecological environment. By deploying a UV radiometer aboard a stratospheric balloon released at Qaidam (QDM) during the Asian summer monsoon (ASM) period in 2019, we provided in situ measurement of the UV profiles from the surface to the upper troposphere and lower stratosphere over the Tibetan Plateau (TP), China, for the first time. Based on two in situ UV profiles accompanied by four ozonesonde measurements, this study exhibited detailed variations of downwelling UV and vertical ozone distributions over the TP during the ASM period. The UV differences between the surface and stratospheric balloon flight altitudes were 16.7, 15.8, 12.6 and 18.0 Wm^?2 during the four ozonesonde launches. Due to the diurnal variations in photochemical production and the stratosphere-troposphere exchange, the integrated ozone columns below 30 km ranged from 184.4 to 221.6 DU from four ozonesonde measurements. A positive correlation between UV attenuation and ozone column was exhibited under low cloud cover and clear sky conditions. The results of this study are expected to improve our understanding of UV and ozone properties, as well as their potential effects on terrestrial ecosystems and living environments over this significant plateau.     

农业面源污染防治研究现状与展望

农业面源污染是影响水环境质量的重要污染源,对水环境的污染贡献率逐年提高,逐渐成为制约农业可持续发展和实现农村现代化的环境瓶颈。文章在广泛调研国内外相关领域研究成果的基础上,综述了农业面源污染防治相关领域的研究进展,主要包括:农业面源污染物流失特性研究、土地利用方式影响研究、农业面源污染控制和治理技术研究、面源污染模型研究、现代电子信息技术的应用以及最佳管理措施(BMPs)的研究与实践等。最后,对农业面源污染控制领域未来重点研究方向进行了展望,并提出了相关建议。