Long term changes in atmospheric N and S throughfall deposition and effects on soil solution chemistry in a Scots pine forest in the Netherlands

In a Scots pine forest the throughfall deposition and the chemical composition of the soil solution was monitored since 1984. (Inter)national legislation measures led to a reduction of the deposition of nitrogen and sulphur. The deposition of sulphur has decreased by approximately 65%. The total mineral-nitrogen deposition has decreased by ca. 25%, which is mainly due to a reduction in ammonium-N deposition (−40%), since nitrate-N deposition has increased (+50%). The nitrogen concentration in the upper mineral soil solution at 10 cm depth has decreased, leading to an improved nutritional balance, which may result in improved tree vitality. In the drainage water at 90 cm depth the fluxes of NO₃⁻ and SO₄²⁻ have decreased, resulting in a reduced leeching of accompanying base cations, thus preserving nutrients in the ecosystem. It may take still several years, however, before this will meet the prerequisite of a sustainable ecosystem.     

Impacts of pollution heterogeneity on population exposure in dense urban areas using ultra-fine resolution air quality data

Traditional air quality data have a spatial resolution of 1 km or above, making it challenging to resolve detailed air pollution exposure in complex urban areas. Combining urban morphology, dynamic traffic emission, regional and local meteorology, physicochemical transformations in air quality models using big data fusion technology, an ultra-fine resolution modeling system was developed to provide air quality data down to street level. Based on one-year ultra-fine resolution data, this study investigated the effects of pollution heterogeneity on the individual and population exposure to particulate matter (PM_2.5 and PM₁₀), nitrogen dioxide (NO₂), and ozone (O₃) in Hong Kong, one of the most densely populated and urbanized cities. Sharp fine-scale variabilities in air pollution were revealed within individual city blocks. Using traditional 1 km average to represent individual exposure resulted in a positively skewed deviation of up to 200% for high-end exposure individuals. Citizens were disproportionally affected by air pollution, with annual pollutant concentrations varied by factors of 2 to 5 among 452 District Council Constituency Areas (DCCAs) in Hong Kong, indicating great environmental inequities among the population. Unfavorable city planning resulted in a positive spatial coincidence between pollution and population, which increased public exposure to air pollutants by as large as 46% among districts in Hong Kong. Our results highlight the importance of ultra-fine pollutant data in quantifying the heterogeneity in pollution exposure in the dense urban area and the critical role of smart urban planning in reducing exposure inequities.     

水培蔬菜法对富营养化水体中氮磷的去除特性研究

利用水培蔬菜法净化富营养化河水，考察了不同形态的氮磷在处理前后的变化，在此基础上阐明水培法去除富营养化水体中氮磷的过程与机理。     

城市污水硝化反硝化及生物脱氮计算

本文论述城市污水硝化反硝化及生物脱氮的设计计算，并用计算示例加以说明．     

应用投加粉末活性炭的膜生物反应器处理生活污水的研究

应用向间歇曝气的膜生物反应器内投加粉末活性炭的新工艺，进行了处理模拟生活污水的研究，将此研究结果与未投加粉末活性炭时的研究结果相比较，表明该工艺不仅可以取得更优的出水水质，而且可以从根本上减少膜阻力，维持高膜通量。     

菏泽市城区酸雨成因分析与对策

大气污染带来的危害已明显影响到人民群众的身心健康，菏泽市城区“十五”以来降水监测的酸雨现状表明菏泽市酸雨污染呈逐年加重趋势，指出了菏泽市城区酸雨污染成因和发展趋势，进而提出了改善城市大气环境质量的建议与对策。     

沈阳区域环境空气中一氧化氮与二氧化氮时空分布规律

以沈阳区域环境空气监测分析结果为依据 ,分析了 1 994～ 1 998年内空气中一氧化氮与二氧化氮时空分布状况及其变化趋势     

观音阁水库水体中氮、磷污染现状及其防治对策

本文通过对观音阁水库的水质进行监测和调查分析，了解观音阁水库水体中氮、磷污染状况及来源。根据监测和调查结果可以判断，磷是观音阁水库中限制性营养盐。通过采取必要的防治对策和措施，控制氮、磷的浓度，不仅可以控制观音阁水库水体富营养化程度，而且还能产生一定的经济效益。     

中国城市污水强化一级处理研究现状与进展

综述了近年来中国城市污水强化一级处理的一些技术方法：化学强化一级处理；生物絮凝吸附强化一级处理；化学一生物联合絮凝强化一级处理。结合当前中国城市水污染控制现状以及亟待解决的突出问题，阐述了城市污水强化一级处理的重要性，同时提出了城市污水强化处理的建议和对策。     

矿化垃圾生物反应床处理NO_X废气的研究

矿化垃圾(稳定化垃圾)是一种良好的生物介质,可作为生物反应床的填料处理NOX废气。实验室研究表明,稳定化垃圾反应床可有效地处理NOX气体,其硝化能力(以N计)可达0.83g/(kg·d)(干重)。NOX去除率受停留时间的影响显著,NOX去除率随着停留时间的缩短而降低。当空床停留时间为1.5min时,NOX气体的平均去除率为76.7%;空床停留时间为15min时,NOX气体的平均去除率为91.0%。在NOX进气负荷低于110mmol/(m3·h)时,NOX消除能力随进气负荷的增加而线性增加。当进气流量一定时,NOX去除能力随着进气NOX浓度的增加而线性增加。