Spatial variability in emissions reduction strategies for sulphur and nitrogen in the UK

The roles of sulphur (S) and nitrogen (N) in causing critical loads exceedance across the UK show considerable spatial variability at the present time. Over much of lowland Britain it appears that the environment can only be protected by reducing N deposition, whilst in upland areas (e.g. most of Scotland and Wales) reductions in S deposition are the primary requirement. Using the Hull Acid Rain Model (HARM) the effects of current and possible future emissions control legislation on critical loads exceedance can be explored. Based on HARM output, the implementation of the UNECE Sulphur Protocol (1994) will bring about a substantial reduction in the amount of S being deposited in the UK, especially in central and southern parts of the country. Some areas will remain where additional reductions in S are required. Over most of the country, however, the need to reduce N deposition will become paramount. The changing contributions and significance of non-UK sources can be estimated.     

Interdependence of air,water, and soil pollution control strategies in a power plant and a kraft mill

An analysis of cross-media (air, water, and soil) emissions resulting from various control strategies is necessary in the evaluations of emission standards as well as control strategies. This paper presents such analysis on seven control strategies for a coal-fired power plant and ten control strategies for a kraft pulp and paper mill. The data illustrated include uncontrolled and controlled emissions to all three environmental media as well as power requirement, and capital and operating costs.     

Control techniques and strategies for regional air pollution control from energy and industrial sectors

The technological options currently available to reduce SO₂ and NO_x emissions including abatement technologies and high efficient energy conversion technologies are reviewed. The energy emission model EFOMENV (Energy Flow Optimization Model-Environment) which takes into account all relevant emission reduction measures is used to determine the cost optimized energy pathway, the ranking of reduction measures and the corresponding costs as a function of given reduction levels of SO₂ and/or NO_x emissions for different scenarios in selected Central and Eastern European countries. It is shown that restructuring of the energy system is a major emission reduction option in all countries but with a potential varying greatly from country to country depending mainly on the existing structure and the age of the plants and on the development of the energy demand. The emission reduction costs for SO₂ in Central and Eastern European countries are 50% to 70% lower than in Western countries due to high potential of fuel/technology switching and energy saving measures. Cost efficient measures to reduce CO₂ emissions also lead to a significant decrease of SO₂ and NO_x emissions.     

Control techniques and strategies for regional air pollution from the transport sector the European case

We still have insufficient knowledge about the way that different types of vehicles are actually used (loads, driving behaviour etc.). This means that most statements on specific and aggregate emissions as well as on the cost-effectiveness of different measures should be judged with caution. There is still large scope for reducing emissions from transport by technical measures. This is particularly true for shipping, off-road vehicles and for most types of road vehicles. Improved maintenance and extended durability of emission control systems seem to be among the most cost-effective measures where road transport is concerned. The contribution from improved grades of diesel and petrol towards lower aggregate emissions of acidifying substances is likely to be small. Changing the modal split could be expected to be an expensive way of reducing air pollution from road transport except for regions suffering from congestion.     

Recent and future advances in air pollution instrumentation

Currently used instruments for the measurement of O₃, SO₂, and the oxides of nitrogen are briefly described. The first utilizes the chemiluminescence of the gas phase reaction of O₃ with ethylene, the second uses the chemiluminescence of excited diatomic sulfur formed in the cool hydrogen flame by reaction between SO₂ and H atoms, while the third depends upon the chemiluminescent reaction NO+O₃. Nitrogen dioxide is thermally dissociated into NO and measured as such. Newer instruments, now under development, that are described include (1) a photofragment detector for NO₂, operating on photolytic cleavage to yield O atoms, which are then measured via the luminescence of their reaction with an excess of added NO, and (2) the UV fluorescence instrument of Okabe.     

Analytical air pollution advection and diffusion models

A review of non-Gaussian analytical solutions of the advection diffusion equation is presented. Their utilization to mathematical models of air pollution diffusion is discussed and the application of a particular solution is suggested. The suggested KAPPAG model uses the Demuth's (1978) solution and can incorporate smoothed observed vertical wind and diffusion coefficient profiles. It is shown that Demuth's solution can represent the realistic situations of the diminishing vertical exchange coefficient at the top of boundary layer.     

Mercury pollution of effluent,air, and soil near a battery factory in Tanzania

Effluent, air, and soil samples near a battery factory in Dar es Salaam, Tanzania, where HgCl₂ is used to prevent mold growth, were collected to explore the potential for pollution of the environment from industrial discharge of Hg. Flameless atomic absorption spectrophotometry was used for Hg determinations. The concentration of Hg in the effluent ranged from <0.2 to 5.2 mg L^?1 and the Hg concentration varied greatly within and among sampling days, showing different peaks. Air contained a mean of 4.0 μg m^?3 with little variation within and between sampling days. Soils near the factory contained high Hg levels, from 6.7 to 472 mg kg^?1 in the immediate vicinity, the highest level being associated with disposal of solid waste (defective batteries). Downwind the concentration of Hg decreased with increasing distance from the factory resulting in a soil concentration of 1.0 mg Hg kg^?1 about 2 km away. Upwind the Hg concentration decreased drastically within a distance of 100 to 200 m.     

Tree bark as a bioindicator of air pollution in Navarra,Spain

During a two year research period from 1992 to 1993, samples of different species of trees were taken in 17 forest stands located in Navarra, Spain. From these samples, bark extracts were prepared in which the pH and the conductivity were measured. The health of the sampling trees was also evaluated by determining the degree of defoliation and decoloration of the canopies. The bark tissue analysis revealed the presence of an environmental acidity gradient that decreased from NW to SE. This coincides with the location of important sources of pollution and their course of transport and dispersion. On the other hand, in the samples ofQuercus ilex a significant correlation between the pH and the defoliation levels (P≤0.01, r=0.62) was found. This fact reveals the potential usefulness of tree bark as a health bioindicator of trees.     

亚洲热带地区的土壤资源及土地利用

Tropical Asia is a region comprising South and Southeast Asia and under strong influence of the Asian monsoon climate.It is characterized by and extremely high population density and by high land use intensity.Paddy rice cultivation is the most important form of agriculture in the greater aprt of the region.Soil resources of tropical Asia have a specific feature in comparison with tropical Africa and America.Ultisols dominate in uplands,and lowland soils like Inceptisols and Histosols are relatively abundant.The latter point is made clearer if we take the landforms of the region with a vast extent of lowlands into consideration.Geologically,tropical Asia with the Himalayan orogeny and active volcanism exhibits a conspicuous contrast to tropical Africa and America with the dominance of the shield structure.This along with the monsoon climate should have determined the basic features of landforms and soil,and acoordingly all the agricultural and social characteristics of tropical Asia today,Although paddy rice cultivation in the lowland is highly sustainable,upland cultivation in extensive Ultisol areas tends to be handicapped by low fertility and high erodibility of the soil,resulting in low sustainability.Land shortage is compelling people to exploit slopelands in hills and mountains,on the one hand,and thus far unutilized coastal lowlands,on the other,Both of these new reclamations are facing to serious land degradation problems todary.Torpical Asia will continue to be the most densely populated region of the wolrd with ever-increasing population.In order to meet the increasing food demand lowlang rice cultivation should beintensified by the infrastructure development to ease the stresses on slopelands and vulnerable coastal lowlands.At the same time,upland crop production in Ultisol areas should be stabilized and enhanced,providing integrated nutrient management and measures for soil conservation.     

Harmonization of air pollution control in the European community

In the first Action Programme of the Environment approved by the Council of Ministers on 22 November, 1973, the Commission of the European Communities was requested to determine criteria, to propose quality objectives and standards, to develop exchanges between Member States of measurement data from pollution control networks, to harmonize produce specification and actions with the industrial sector. A critical review is given in this presentation of the progress made in this respect at Community level and of the difficulties met. It can be stated that important progress has been made to harmonize national policies and to elaborate a Community policy in this field, notwithstanding the difficulties of smoothing away differences in existing and established national policies and situations.     

The cost of air pollution damage in Austria 1970

Using recently published emission factors and the official Austrian consumption data the total emissions of air pollutants in Austria in 1974 are calculated. Comparing these emissions to the U.S. emissions in 1968 and assuming comparable situations and a linear cost-emission relation, Austrian cost of air pollution damage figures are derived from the estimated U.S. figures.     

新疆农田残膜污染现状及防控策略

塑料污染是全球性的难点问题,残膜污染是塑料污染在农田的表现形式。新疆是中国重要的农产品生产基地,覆膜种植总面积达347.8万hm2,年地膜投入量超过20万t,是全国残膜污染最为严重区域,具有代表性。总结新疆农田残膜污染的特点、综合治理现状以及存在问题对全国农田残膜污染的治理有较大的借鉴作用。该文应用文献检索归纳、信息查阅以及田野调查等研究方法,对新疆农田残膜残留区域分布特点与残膜在土壤中的空间分布特点进行了总结归纳;分析了地膜投入成本、地膜力学性能以及回收因素等残膜产生成因;对近年来农田残膜污染综合治理技术进行了梳理,总结了农艺防治、可降解地膜、多种回收组合模式以及机械化回收等4大类综合治理技术。最后,探讨了目前残膜污染综合治理中存在的农机农艺融合综合治理、残膜机械化回收、系统性农艺措施以及监测评价等问题,分析了完善残膜污染治理法规、把握农机-农艺-农膜相结合理念、加大耕层残膜的分级治理、研究新型地膜技术以及创新地膜应用栽培模式等污染防控策略。研究表明:现阶段PE地膜仍是农业生产的主要应用方式,开发新型地膜与可降解地膜,实现PE地膜的完全替代是未来的研究目标;新疆农田残膜污染治理应坚持"遏制增量,减少存量"的方针,加大地膜的机械化回收,规范农用地膜的使用与回收再利用,优化种植模式,建立残膜污染治理的可循环模式,以期对典型区农田残膜污染综合治理提供借鉴参考与解决思路。     

Carbon sequestration in Norway spruce in south Sweden as influenced by air pollution,water availability,and fertilization

Carbon sequestration in 30 yr old Norway spruce in south Sweden following manipulation of nutrient and water availability is presented. The site has an annual precipitation of 1100 mm and a deposition of about 20 kg N and 25 kg S per ha^?1 yr^?1. The soil type is a poorly developed podzol. Treatment include irrigation; artificial drought; ammonium sulphate addition; nitrogen-free-fertilization and irrigation with liquid fertilizers including a complete set of nutrients. The experiment has a randomized block design with four replicates per treatment. A comprehensive investigation of the above ground C storage on an areal basis was made at the start of the experiment and after 3 yr of treatment. After 3 yr of treatment with simulated N-S deposition using ammonium sulphate (100 kg N, 114 kg S ha^?1 yr^?1), C accumulation rates in the above ground compartments had increased by 37%. Similarly, irrigation caused increased C accumulation rates by 25%, whereas simulated drought during the vegetation period during 2 yr followed by 1 yr of recovery caused a 15% reduction of the C accumulation rates. Irrigation combined with liquid fertilization (100 kg N ha^?1 yr^?1), including all important nutrient elements, led to 65% increase in C accumulation rates compared to the control. The C sequestration of the latter treatment gradually increased and, during yr 5 of treatment, 8.6 Mg C ha^?1 accumulated in stems and branches, compared to 3.6 Mg ha^?1 for the control. It is concluded that there is a strong interaction between N-deposition and C accumulation rates in Norway spruce in south Sweden. The C accumulation rates are also sensitive to water availability. The study indicates a great potential to cultivate Norway spruce in south Sweden as a renewable energy source. A shift in energy source from fossil fuels to renewable energy sources will directly reduce the net emissions of CO₂ to the atmosphere.     

Observations of water,air and soil pollution in Israel and vicinity from the ERTS-1 imagery

Israel is a participant in the Earth Resources Technology Satellite Program (ERTS). The imagery of Israel and vicinity taken by the Multi Spectral Scanner of the ERTS-1 Satellite has been the subject of analysis in a multidisciplinary research program. The objectives of the program are mapping of agricultural crops, mainly wheat and orange groves, mapping of natural vegetation, and studies for Israeli hydrology, arid regions research, geology, and oceanography. Cases of water, air, and soil pollution have been observed in the imagery on several dates, and are reported in this paper. These are: oil slicks in the Gulf of Suez and possibly near Haifa; smoke plumes, extending over some 100 km in a nearly straight line along the Gulf of Suez, and soil pollution caused by copper mine effluents in the Arava Valley in Israel. The images of these cases of pollution are presented and ‘space signatures’, i.e., the radiometric spectral characteristics of these cases of pollution as seen from space are also given.     

Effects of ambient air pollution on wheat and rice yield in Pakistan

Open-top chambers ventilated with ambient or chiarcoal-filtered air were used to assess the impact of air pollution on the yield of local cultivars of wheat and rice, at a site on the outskirts of Lahore. At this location, 6-h mean O₃ concentrations reach 60 ppb in certain months, and annual mean NO₂ concentrations are 20–25 ppb. The experiments showed significant yield reduction in two successive seasons which ranged from 33% to 46% in wheat and from 37% to 51% in rice. The major yield parameter affected was the number of ears or panicles per plant, although there was also evidence of small effects on 1000 grain weight and on the number of grains per ear/panicle. These results have significance in terms of the maintenance of agricultural yields as pollution emissions rise in south and south-east Asia.     

The problem of aliasing in inferring long-range air pollution transport to Mauna Loa,Hawaii

Water, Air, & Soil Pollution - Choice of sampling strategy or criteria for selection of aerosol concentration data from a time series record can lead to errors in estimating periodic...     

Role of air pollution in forest decline in Eastern North America

Evidence for and against three general mechanisms by which air pollution stress may cause or contribute to forest decline in eastern North America is examined. These mechanisms are (1) soil acidification, cation nutrient depletion, and subsequent Al toxicity, (2) direct and indirect effects of gaseous pollutants on the physiology and growth of forest trees; and (3) excess nitrogen deposition and subsequent soil acidification or physiological injury. Recent studies have revealed reductions in base saturation in some sites (both polluted and pristine), but the consequences of these changes to forest health and nutrition are not resolved. Aluminum toxicity may contribute to forest decline in red spruce (Picearubens L.) in high-elevation sites, but the data are contradictory. In forested landscapes in which regional decline (reduced tree growth and/or dieback) is reported, O₃ is the only gaseous pollutant documented as a contributing factor in the eastern North America. Whereas this secondary pollutant exhibits a regional distribution and occurs at potentially phytotoxic levels, a linkage between O₃ and forest decline is substantive only for loblolly pine (Pinustaeda Sarg.) in the southeast. Studies in high elevations do not support the hypothesis that O₃ or hydrogen peroxide directly affects the growth of red spruce or fraser fir (Abiesfraseri Poir.).However, preliminary data link chronic-level O₃ exposure with indirect effects, principally changes in drought tolerance in low-elevations (e.g., P. taeda) nd winter hardiness in high elevations (e.g., P. rubens).The emerging data on the role of air pollution as an environmental stress indicate that indirect effects (i.e., responses in which pollution alters the plant's ability to compete for limited resources or withstand other environmental stresses) are more important than direct effects (e.g., foliar necrotic lesions). Nitrogen saturation has been offered as an hypothesis for P. rubens decline, but no experimental data exist supporting this hypothesis.     

Organization of long range transport of air pollution monitoring in Europe

In the 1950s a network of stations for observation of the chemical composition of air and precipitation was established in Europe. Analyzing these data, Oden (1968) was able to show that a central area in Europe with highly acid precipitation was expanding from year to year. This was further substantiated by Granat (1972), and the explanation is the increasing use of fossil fuels in Europe. In 1969, the problem was examined by OECD, and on the initiative of the Scandinavian countries, a joint research program to study the long range transport of air pollutants was started in 1972. The program will be completed with a final report in 1976. In this program, atmospheric dispersion models are used to describe emission, dispersion and deposition of SO₂ and sulphate with particular emphasis on the acidification of the precipitation. An emission field has been constructed for Europe, and data from the European weather forecasting system are used for the dispersion calculations. Calculated concentrations and deposition are compared with data from about 70 ground stations and measurements from aircraft. Results show that the main cause for acidification of precipitation is the increasing use of fossil fuels. Large amounts of H₂SO₄ can be transported over distances up to a few thousand kilometers. In southern Scandinavia where the soil is highly acid (podsol), this has caused severe damage to life in rivers and lakes, and it is feared that in the future, there will be serious damage to forestry. In the Alps, where the soil has a high carbonate content, such effects are not expected. The long range transport of air pollutants has also been shown to increase the corrosion of materials. Work is now in progress to establish a more permanent system for the monitoring of air pollutants in Europe. The first plans for such a system were presented at the meeting in Oslo in December 1974, where countries from both Eastern and Western Europe participated. The work is supported by the Economic Commission for Europe, UN, in cooperation with other international organizations such as the World Meteorological Organization and the GEMS program of the United Nations Environment Programme. In this connection, studies have also been taken up in several countries concerning the effects of the long range transport of air pollutants. In the future monitoring system, a coordination of these efforts is envisaged.     

Significance of leaf surface characteristics in plant responses to air pollution

Plant responses to air pollution were found to vary with type of leaf vesture. Considerable reduction in leaf area, leaf biomass, total plant biomass and chlorophyll content was observed in plants having pilose or pubescent leaf surface as compared to plants with glabrescent leaf surface. The study shows the importance of leaf vesture in determining response of plants to air pollution.