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1.
Acid rain has become a major environmental concern, the current extent of which is illustrated in this paper. Maps of both pH and H+ deposition in precipitation have been developed for the continental United States by analyzing laboratory pH data from nine precipitation chemistry networks and two single stations spread across the continental United States and southern Canada during the late 1970's. Average laboratory pH values were obtained or calculated for approximately 100 stations, and isopleths of weighted mean pH and mean annual H+ deposition in precipitation were drawn. Results of this analysis show that in spite of a wide variety of collection methods and sampling intervals, there is remarkable uniformity in the average pH among the various stations. The northeastern United States continues to exhibit the most acidic precipitation, with remaining portions of the eastern United States, states along the western coastline and a pocket in central Colorado also experiencing acid precipitation.  相似文献   

2.
Due to acidification, 18 Norwegian stocks of Atlantic salmon are extinct and an additional 8 are threatened. In the two southernmost counties, salmon is eradicated. Due to the high acid sensitivity, production of salmon was greatly reduced as early as 1920, several decades before acid rain was recognized as an environmental problem. International agreements on reduced atmospheric emissions will reduce acidification effects in Norway substantially during the coming 20 to 50 years. However, the extreme acid sensitivity of salmon makes the destiny of this species in Southern Norway uncertain. Liming is an effective measure to protect and restore fish populations in acidified waters. Liming of acidified salmon rivers has become important in Norway in recent years which in combination with reduced emissions will be an important contribution to protection of the Atlantic salmon species. In this paper we give an overview of the effects of acidification on Norwegian salmon and discuss different aspects of mitigation measures; the expected effect of international agreements on reduced atmospheric emissions, the expected effect of liming on salmon production and the possibilities of re-establishing self sustaining salmon stocks in limed rivers.  相似文献   

3.

Purpose  

Acid rain is a problem of increasing agricultural, environmental, and ecological concerns worldwide. In recent years, coupled studies have been conducted to evaluate impacts of simulated acid rain (SAR) on Latosol in China. However, no efforts have been devoted to investigating which soil parameters are most sensitive to the influences of SAR. In this study, we addressed the issue using the principal component analysis (PCA) and principal factor analysis (PFA) techniques.  相似文献   

4.
中国农田土壤环境质量管理现状与展望   总被引:7,自引:1,他引:7       下载免费PDF全文
农田土壤环境质量保护与管理是保障粮食安全和农业可持续发展的重要前提。近年来,随着我国社会经济的快速发展,农田土壤环境质量退化和土壤污染问题逐渐凸显。经过几十年的努力,我国目前基本形成以"土壤污染防治法"和"土壤污染防治行动计划"为核心政策,相关配套管理办法、标准和技术规范等为基础的土壤环境质量管理体系。本文简要梳理了我国农田土壤环境质量状况与污染成因,回顾了我国农田土壤环境保护及环境管理的发展历程,总结了我国农田土壤环境质量管理与标准体系建设的最新进展,对比分析了农田土壤环境管理的国际经验,针对性地提出了我国农田土壤环境管理的对策与展望,以期为我国农田土壤环境质量管理及污染防控提供参考和借鉴。  相似文献   

5.
Zheng  Wenhui  Li  Renshan  Yang  Qingpeng  Zhang  Weidong  Huang  Ke  Guan  Xin  Wang  Silong 《Journal of Soils and Sediments》2019,19(3):1239-1249
Journal of Soils and Sediments - Acid rain is a primary environmental problem in Southern China. However, the effect of acid rain on soil respiration rarely received attention, especially in...  相似文献   

6.
Nowadays, acid rain is generally noticed as a global environmental problem. While acid rain has very much to do with the air pollutants, the relation between air pollution and chemical constituents in precipitation is not understood clearly yet. It is important to measure a variation of ion concentration in precipitation in short term for understanding the formation mechanism of acid rain. Therefore, an automatic continuous measurement system of chemical constituents in precipitation was developed and put into practical use in this study. The developed system was able to collect automatically every 1mm of precipitation and analyze major ions within 20 minutes.  相似文献   

7.
Acid rain at a rural site in Chongwon (KHN), central Korea has been under observation since 1990. To substantiate the 10-year observations, rain samples from six other sites were also collected and analyzed. Results show that acid rain occurred frequently at all sites. At KHN, seasonal and annual variability of pH values had a 10-year VWM value of 4.67 and an arithmetic mean value of 5.09. In general, a high value of pH occurred during springtime when the occurrence of yellow sand (dust) was prevalent in East Asia; during summer, heavy rain usually contained neutral pH values. During other seasons, the degree of acidic precipitation usually coincided with certain air flows. Most frequently, air flows and cyclones coming from south and central China often resulted in precipitation with low pH values observed in Korea. Using daily satellite observations from 1996, we have also been monitoring the long-range and large-scale transport of air pollutants (LSTAP) over East Asia. Many samples of LSTAP were obtained when they were crossing the Yellow Sea and moving over the Korean Peninsula and to SW Japan. The width of the Yellow Sea is ca. 350~700 km and air pollutants take 1~2 days to cross it. Cases of acid rain in Korea clearly correlate wth the LSTAP from source regions in China.  相似文献   

8.
K. MINAMI 《土壤圈》2005,15(2):156
To feed an increasing population, large amounts of chemical nitrogen fertilizer have been used to produce much of our food, feed and fiber thereby increasing nitrogen levels in soils, natural waters, crop residues, livestock wastes, and municipal and agricultural wastes, with national and international concern about its potential adverse effects on environmental quality and public health. To understand these phenomena and problems, first the nitrogen cycle and the environment are described. Then recent trends for nitrogen cycling through the food and feed system, N2O emissions from fertilized upland and paddy soils, and NO3- pollution in ground water in Japan are reported. Finally, mitigation strategies in Japan for reducing N2O emission and NO3- pollution are proposed, including nitrification inhibitors, controlled release fertilizers, utilization of plant species that could suppress nitrification, utilizing the toposequence, government policy, and appropriate agricultural practices. Of all the technologies presented, use of nitrification inhibitors and controlled release fertilizers are deemed the most important with further development of these aspects of technologies being expected. These practices, if employed worldwide, could help reduce the load, or environmental deterioration, on the Earth''s biosphere.  相似文献   

9.
Questions concerning the value society places on the benefits and costs of control measures for acidic deposition cannot be fully achieved without considering the views held by the public-at-large. While numerous opinion polls have been conducted on acid rain, to date no systematic review of these data has been undertaken to identify underlying trends. This paper summarizes a comprehensive analysis of existing public opinion data in Canada and the U.S. from 1979 to the present, with particular attention given to identifying longitudinal trends, comparisons across jurisdictions, demographic group differences and comparisons with other issues. It is concluded that over the past five years, the North American public has become aware of acid rain as an environmental issue and, despite a limited understanding of the problem, believe it to be a serious one. Concern about acid rain has by now reached the level where most believe concrete actions must be taken, and a majority are willing to help pay for abatement programs. Canadians and residents of regions susceptible to acid rain damage have typically been more informed and concerned about acid rain, but such regional and national differences have diminished over time as the issue has become more widely recognized. These findings are discussed in terms of implications for policy and education strategies.  相似文献   

10.
为了客观反映环境质量变化趋势以及为环境管理决策提供科学依据,以陕西省环境质量监测数据为基础,采用Spearman秩相关系数法,对陕西省2001-2007年空气、酸雨、地表水及噪声等方面的环境质量变化情况进行了分析.结果表明,"十五"以来,陕西省环境质量总体呈好转趋势,城市空气质量持续改善,城市尘污染防治成效显著;酸雨发生率普遍较低,仅有局部地区出现酸雨,分布相对稳定;水环境质量总体恶化的趋势得到遏制,地表水污染呈减轻趋势;城市噪声污染控制效果明显,城市区域噪声和交通噪声质量明显改善.  相似文献   

11.
Shah  Jitendra J.  Nagpal  Tanvi  Johnson  Todd  Li  Jia  Peng  C. 《Water, air, and soil pollution》2001,130(1-4):235-240
China's continuing dependence on coal suggests a need for a cost-effective strategy to address SO2 and acid rain impacts. Results of modeling studies show that although there are important transboundary aspects of acid rain in Asia, the majority of emissions and damages lie within China. This implies that intra-regional cooperation within China, and cost-effective sulfur control are paramount for limiting acid rain damages. This article discusses the costs and benefits of six primary and secondary control and policy options using the RAINS-ASIA and UR-BAT models. The local health benefits were estimated to be an order of magnitude larger than the ecosystem benefits at the regional level. All abatement options involve substantial costs, except intensive energy efficiency which is the most cost effective with the rate of return of almost 200 per dollar as compared to around 6 for the other options.  相似文献   

12.
Simulated acid rain did not alter respiration rates of microbial associations on dead Spartina alterniora from Delaware salt marshes or on dead Carex lyngbyei from Oregon brackish marshes. Since these dead plant-microbe associations have a strong buffering capacity for acid rain, the microbial associations did not experience a low pH. In contrast, Phragmites australis has a low buffering capacity and microbial respiration was reduced at least 25 % by acid rain. When dead plant-microbe associations from freshwater marshes and various terrestrial plant populations were immersed in simulated acid rain, the rain water equilibrated at pH's from 3.9 to 5.0 and were characteristic of the various species. The different buffering capacities of such dead plant-microbe associations may explain the inconsistent results published from decomposition studies and may serve as a quick and easy method of assessing the probable impact of acidic deposition on decomposition processes.  相似文献   

13.
Several multilateral initiatives on acid rain control were advocated in the 1990s, and extended through multiple channels in East Asia. There is, however, little coordination between those initiatives. The geopolitical make-up of the region has also hampered further progress in regional cooperation on the issue. In this paper we first examine the major features and weaknesses of existing regional environmental cooperative schemes. Second, we review collective initiatives on the acid rain issue, and examine how further progress has been hindered by the inherent inadequacies of the schemes. Finally, we consider whether and how regional cooperation on the acid rain issue may be promoted, and try to draw some implications from the European experience that might help enhance regional cooperation.  相似文献   

14.
Concern for the better management of environmental resources grew during the 1980s. While this concern encompassed the misuse of the Third World's resources, those nations' governments and their peoples showed less awareness of the environmental damage being done in their quest for development. Environmental degradation has reached serious proportions in Algeria where oil wealth has masked failings of agricultural production and, together with industrialization, has provided a ‘veneer’ of economic development. The vulnerability of Algeria's natural environment and the fragility of its ecosystems have been stressed by Cǒte (1983). Once cleared, Algeria's woodlands and forests are slow to re-establish and surface deposits are easily erodable. Soils were largely formed under past climatic conditions, and so cannot be restored naturally by present pedogenetic processes. Such an environment is difficult and delicate to exploit to any high degree of agricultural intensification and is under increasing demographic pressure. Culturally and organizationally the agricultural system is far from ideal if agriculture is to be sustained. Often in Algeria the highest rainfall falls on the steeper slopes while the gentler slopes receive insufficient for agriculture. Only 500 000 hectares out of Northern Algeria's 38–40 million hectares receive more than 600 mm of rainfall and have slopes of less than three per cent (Cǒte, 1983). As much as 20 million hectares of Northern Algeria were identified by Dregne (1983) as … ‘vulnerable to desertification’ with large areas falling into his ‘severe’ risk category. This study seeks to demonstrate the dimensions of environmental degradation through observations and the monitoring (during the 1980s) of Algeria's media: largely newspaper and television reports. Particular emphasis is placed on the growing environmental ‘crisis’ since 1988. It should be stressed that the Algerian Government uses a controlled media to disseminate official information. Misuse and overuse of environmental resources have combined with inadequate government economic policies and a neglect of ecological issues to cause the ‘crisis’.  相似文献   

15.
Boyle  J. F.  Rose  N. L.  Bennion  H.  Yang  H.  Appleby  P. G. 《Water, air, and soil pollution》1999,112(1-2):21-40
There is growing concern about the environmental impact of rapid economic growth in China. The problem is compounded by the scarcity of baseline data on the state of China's natural environment. As a step towards solving this problem, palaeolimnological methods have been applied to seven lakes in the Jianghan Plain, China, to evaluate recent changes in human impact. Lake sediment cores show enhanced concentrations of fossil fuel derived spheroidal carbonaceous particles (SCP) and Pb at all sites across the Jianghan Plain. The distribution of these industrial contaminants shows the overwhelming influence of the industrial cities. Wuhan dominates the fossil fuel derived pollution, while the copper smelter at Daye dominates the heavy metal pollution. Analysis of sediment diatom assemblages indicates mean total phosphorus concentrations of greater than 40 μg L-1 P in the lakes of the more intensely agricultural western part of the Jianghan Plain. The sediment concentration profiles for biogenic elements at these sites indicates a post-1960 eutrophication. Evidence for eutrophication in the eastern lakes is much weaker, though some evidence is present at all sites. The tracers of industrial pollution (Pb and SCP) correlate with Mn in the many of the lake sediments. This is compatible with both soil acidification, and soil gleyification due to intensified rice production.  相似文献   

16.
Wind-blown rain, rain splash, and films of free moisture play important roles in the epidemiology of many plant diseases. The effects of simulated rain acidified with sulfuric acid were studied on several host-parasite systems. Plants were exposed in greenhouse or field to simulated rain of pH 3.2 ± 0.1 or pH 6.0 ± 0.2. Simulated ‘rain’ of pH 3.2 resulted in: (1) an 86% inhibition in telia production of Cronartium fusiforme on Quercus phellos; (2) a 66% inhibition of reproduction of Meloidogyne hapla on field-grown Phaseolus vulgaris; (3) a 10% decrease in the severity of Uromyces phaseoli on field-grown Phaseolus vulgaris; and (4) an inhibition of Rhizobium nodulation of Phaseolus vulgaris and Glycine max by an average of 73%. Effects on halo blight of kidney bean (caused by Pseudomonas phaseolicola) depended upon the segment of the disease cycle in which the ‘rain’ occurred: (a) simulated rain of pH 3.2 applied to plants before inoculation stimulated disease development; (b) suspension of inoculum in ‘rain’ of pH 3.2 decreased inoculum potential; and (c) ‘rain’ of pH 3.2 applied to plants after infection inhibited disease development. Scanning electron microscopy of epicuticular waxes on leaves of Quercus phellos and Phaseolus vulgaris showed marked erosion of those surfaces by ‘rain’ of pH 3.2, indicating possible influences on the structure and function of plant cuticles. These results suggest that the acidity of rain is a new parameter of environmental concern, and underline the need for study of the consequences of prolonged exposure of both agronomic and natural ecosystems to this stress factor.  相似文献   

17.
In recent years it has become increasingly recognized that resolving desertification is better achieved by winning over the local population than by imposing an ‘expert’ solution from above. However, little research has so far been conducted into the environmental perceptions of the general public in China. This study aimed to contribute to this important area of research by empirically exploring the lay public's environmental perceptions regarding desertification in Minqin County in Gansu Province, northern China. The study adopted as its theoretical underpinnings Zube and Sell's Process Model of the Perception of, and Response to, Environmental Change (1986). The primary data was collected via a questionnaire survey (n = 1138) administered between 14 and 31 December 2002. The major findings of the questionnaire survey were: (1) although many respondents were aware of desertification, they did not fully understand the various issues involved; (2) respondents' perceptions of desertification were significantly affected by their personal attributes; and (3) there was a considerable difference in the way in which desertification in Minqin County was perceived by experts and laymen respectively. As far as the policy implications of these findings are concerned, two approaches are essential to encourage self‐motivated social participation to resolve desertification in Minqin County: (1) the different perceptions of laymen and experts of the problem must be addressed at the outset in the formulation of any desertification‐mitigating policies; and (2) any attempts to educate the lay public should not assume the existence of a homogenous community of like‐minded people. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

18.
ZHAO Qi-Guo 《土壤圈》2001,11(4):289-299
Problems in water-land resources and environmental quality increase with the fast economic development in the coastal region of southeastern China,This region has the highest density in population,industry and towns in China,and the large export-oriented economy makes itself a strategic importance while China enters into international markets.The problems facing to this region include arable land reduction,land degradation aggravation,high percentage of built-up land with high rate of expansion,expanded non-point pollution,deteriorated water quality,decreasing biodiversity,destroyed ecosystems,sever air pollution,frequently occurred acid rain,and multi-pollutants.The important reaarch fields in the near future should include a )influence of high-intensity exploitaion of resources on changes of environment quality and its feedback;b) influence processes ,key mechanisms and adjustment principles for degradation of water,land-,and air-resources and environmental quality;c)evolvement processes and nurturing theory of bioiversity and ecological resourcs;and d) spatio-temporal variaiton and human-induced effects on regional resources and environment quality .Strategies for sustainable development in the region are as follows:a) controlling to ensure basic cultivated land area;b) enforcing remediation of polluted water environment,and controlling non-point pollution;c) strengthening ecological construciton and ecological security;and d) controlling multi-pollution and preventing trace toxic pollutants.  相似文献   

19.
The RAINS (Regional Air Pollution INformation and Simulation) model was developed at IIASA as an integrated assessment tool to assist policy advisors in evaluating options for reducing acid rain. In recent years, the European implementation of this model has been used to support the negotiations on an updated, effect-based Sulphur Protocol under the Convention on Long-range Transboundary Air Pollution. The development of future strategies for reducing the environmental damage caused by air pollutants requires a multi-pollutant, multi-effect approach. In this context, the RAINS model is being further developed to include ozone. This paper outlines the development of an integrated assessment model for tropospheric ozone, which combines information on the emissions of ozone precursors (NOx and VOCs), the available control technologies and abatement costs, the formation and transport of ozone and its environmental effects in Europe.  相似文献   

20.
代表性国家和地区耕地休耕补助政策及其对中国的启示   总被引:8,自引:5,他引:3  
为保证耕地休耕制度的顺利实施和成效的长久保持,中国近年来不断探索制定科学合理的耕地休耕补助政策.美国、日本、欧盟、中国台湾等国家和地区已经具有多年的休耕实践经验,且都十分重视对休耕农民的补助问题.该文采用文献资料法、对比分析法及归纳总结法,在分析美国、日本、欧盟、中国台湾等代表性国家和地区休耕补助实践的基础上,对休耕补助目的、实施模式、补助形式、补助依据及资金来源等进行了梳理和归纳.针对中国休耕补助政策中可能存在的问题,提出今后应从补助目的动态化、补助效益最大化、补助类型差异化、资金来源多样化、配套措施制度化等方面完善补助政策的改进建议,并尝试构建了中国耕地休耕补助政策的初步框架.  相似文献   

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