酸雨的研究现状及新兴趋式的可视化分析

以Web of Science核心集中的SCI-E、SSCI、CPCI-S及中国知网CNKI为数据源,以2000—2017年所发表的有关酸雨研究的2 333篇SCI及2 107篇中文文献为分析对象,分析了相关文献的时空分布。使用可视化软件Cite Space V生成了期刊共被引图谱、作者合作图谱、作者共被引图谱、关键词共现图谱及参考文献共被引图谱,分析了该研究领域的研究现状及新兴趋式。国际上,该领域近4年来的研究热度逐年上升,高产期刊为Atmospheric Environment,高被引期刊为Wa-ter,Air,&Soil Pollution,中国和美国是从事酸雨研究的主要国家,该领域的高产机构是中国科学院。同时还介绍了从事酸雨研究的主要科研团队和有影响力的个人。由关键词共现分析和参考文献共被引分析可知,中国的酸雨问题是目前的研究热点,酸雨对植物光合作用的影响和中国南方的酸雨问题是当前研究出现的新兴趋式。国内方面,我国于2010年左右对酸雨研究的热度达到顶峰,主要的研究机构是江南大学、南京大学及浙江大学。此外,也介绍了国内从事酸雨研究的主要个人及科研团队。     

中小城市污水排水问题及对策研究

为解决中小城市污水排水问题,进一步加强城市排水管理,改善城市水环境,杜绝雨污混排,提高污水处理率,分析和探讨了中小城市在污水排水系统建设、管理、维护中存在的问题,针对排水法规不健全、污水管网不完善、雨污分流难、管理不到位等问题进行原因分析,提出加强排水制度建设、加快排水设施的建设、加强排水管理、加强宣传教育等措施.     

深圳市近年来酸性降水特征及其成因分析研究

通过研究深圳市2006年-2012年的酸雨时空分布、降水的化学组成及其成因分析,结果表明,深圳市降水pH值的范围在3.18~8.73之间,平均值为5.36,属于酸雨污染较为严重的地区。深圳市在2006年-2012年间,降水的pH值有逐步下降的趋势,深圳市春夏季降水酸化程度较低,秋冬季酸化程度较高,主要与降水量直接相关。通过对降水的化学组分进行分析发现,深圳市酸雨类型硫酸和硝酸混合型,硫酸根和硝酸根对降雨中的pH值影响较大,雨水中的硫酸根和硝酸根主要来自工业和交通污染。     

THROUGHFALL IN PLANTED STANDS OF FOUR SOUTHERN PINE SPECIES IN EAST TEXAS1

Throughfall was measured during 1978–79 beneath the canopies of adjacent stands of four major southern pine species, all on identical soil type and topography in the Stephen F. Austin Experimental Forest. Observations from 44 storms in a randomized network of 15, 5.08 cm PVC gages in a 0.4 ha plot of each species showed that throughfall expressed as percent of storm precipitation, is greatest under longleaf pine and least under loblolly pine; throughfall under shortleaf and slash pine did not differ significantly. Generally, through-fall decreased with storm size and intensity, with distance from the nearest tree stem, and is greater during summer half-year (May–October). Canopy drips, apparently accounting for the greater throughfall for the gage position closer to the stems, were more numerous than reported elsewhere. The 5.08 cm PVC gages proved to be acceptable substitutes for standard nonrecording gages in measuring throughfall. A network of 15 such gages was sufficient to sample throughfall data with 90 percent accuracy in each of the four southern pine plantations.     

AN EVALUATION OF PRECIPITATION GAGE DENSITY IN A MOUNTAINOUS TERRAIN1

ABSTRACT: Inter-station analysis was employed to evaluate the adequacy of the precipitation network in topographically complex West Virginia. A 25-year period was determined as the minimum lingth of record needed for relatively stable and fairly accurate estimates of long-term (50-year) precipitation and in frequency analysis. Data from the 83 National Weather Service stations with 25-year records were adjusted for consistency and evaluated separately by zones east (31 stations) and west (52 stations) of the Appalachian divide. Correlation coefficients (r) and average standard errors of estimate were computed for all station pairs within 50 miles distance and 1000 feet elevation difference of each other. The third polynomial equation of inter-station distance eliminated using elevation and land slope as the criteria in network design in this mountainous terrain. A network with (r) = 0.9 estimates annual precipitation with accuracy as great as 5 percent, but requires about 250 additional gages (i.e., about 200 percent of the present density).     

长江中游致洪暴雨天气气候特征

本文从建国以来长江中游地区发生的所有暴雨事件中选出四个典型年，并从这些典型年的暴雨个例中得出暴雨和大暴雨和大暴雨的分布范围和暴雨特征，由此而造成的特大洪水情况，以及洪涝灾害对国民经济的影响。最后应用天气归纳方法分析了暴雨的大尺度环流背景。     

Acid-forming emissions in Alberta,Canada

The sulphur dioxide and nitrogen oxides emissions from all sources in Alberta, Canada, during 1982 amounted to 488,297 and 353,511 tonnes, respectively. During this year deposition of wet sulphate from all stations in the province, 8 kg ha^–1 yr^–1, compares well with the five-year average (1978–1982) value of 10 kg ha^–1 yr^–1. These measurements are about one-half of the wet sulphate deposition criteria of 20 kg ha^–1 yr^–1 established for protecting the moderately sensitive aquatic ecosystem in eastern Canada. Due to dry, cold, continental climate conditions of Alberta, dry sulphate or sulphur deposition is equally or more important than wet deposition. No effects of the long-range transport of atmospheric pollutants (LRTAP) on the ecosystems in Alberta have been observed to date. Atmospheric deposition target loadings of SO₄ ^–2, NO₃ ^–, and H⁺ for Alberta and western Canadian environmental conditions should be developed to protect the highly sensitive ecosystems. Some future research and monitoring priorities for Alberta and western Canada are outlined.     

Urban air pollution and atmospheric diffusion research in China

Air pollution has become a serious problem in China as a result of that country's efforts in the last 30 years to become a great industrial power. The burning of coal, which currently provides over 70% of all China's energy needs, is a major source of air pollution. Because Chinese coal is high in sulfur and ash content and because most combustion devices in China have low efficiencies, SO₂ and particulate emissions are a serious problem and are comparable to or exceed those found in many countries that are much more industrialized. Although most coal is burned in North China, acid precipitation is most severe in South China because of the lack of buffering loess dust found in the former region.The Chinese government has already taken major steps to mitigate air pollution, such as relocating polluting industries, supplying coal with lower sulfur content, using gas instead of coal for residential heating, and levying fines on industries that exceed pollution standards. Atmospheric environmental impact assessment (AEIA) is also required for all major new projects. This article describes three types of mathematical diffusion models and field and wind-tunnel experiments that are used in such assessments.The Chinese authorities believe that a range of technological, managerial, locational, and behavioral changes must be effected before the air of Chinese cities can be significantly improved.     

Management strategy for acidic deposition in Western and Northern Canada

The governments of British Columbia, Alberta, Saskatchewan, Manitoba, Northwest Territories, and Canada held joint consultations in 1980 to review the available information on acid rain from Western and Northern Canada. It was concluded that acid rain might become a problem in the future and, hence, a research, monitoring, and management strategy for acidic deposition was needed. An overview of the joint governments' management strategy, organization of research and monitoring programs, and accomplishments to date are discussed in this article.The authors are members of the Technical Committee for the Long Range Transport of Atmospheric Pollutants (LRTAP)/Acid Deposition in Western and Northern Canada, and represent Alberta and British Columbia, respectively.