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Sample records for acid rain ph

  1. Acid Rain, pH & Acidity: A Common Misinterpretation.

    ERIC Educational Resources Information Center

    Clark, David B.; Thompson, Ronald E.

    1989-01-01

    Illustrates the basis for misleading statements about the relationship between pH and acid content in acid rain. Explains why pH cannot be used as a measure of acidity for rain or any other solution. Suggests that teachers present acidity and pH as two separate and distinct concepts. (RT)

  2. Acid Rain

    USGS Publications Warehouse

    Bricker, Owen P.; Rice, Karen C.

    1995-01-01

    Although acid rain is fading as a political issue in the United States and funds for research in this area have largely disappeared, the acidity of rain in the Eastern United States has not changed significantly over the last decade, and it continues to be a serious environmental problem. Acid deposition (commonly called acid rain) is a term applied to all forms of atmospheric deposition of acidic substances - rain, snow, fog, acidic dry particulates, aerosols, and acid-forming gases. Water in the atmosphere reacts with certain atmospheric gases to become acidic. For example, water reacts with carbon dioxide in the atmosphere to produce a solution with a pH of about 5.6. Gases that produce acids in the presence of water in the atmosphere include carbon dioxide (which converts to carbonic acid), oxides of sulfur and nitrogen (which convert to sulfuric and nitric acids}, and hydrogen chloride (which converts to hydrochloric acid). These acid-producing gases are released to the atmosphere through natural processes, such as volcanic emissions, lightning, forest fires, and decay of organic matter. Accordingly, precipitation is slightly acidic, with a pH of 5.0 to 5.7 even in undeveloped areas. In industrialized areas, most of the acid-producing gases are released to the atmosphere from burning fossil fuels. Major emitters of acid-producing gases include power plants, industrial operations, and motor vehicles. Acid-producing gases can be transported through the atmosphere for hundreds of miles before being converted to acids and deposited as acid rain. Because acids tend to build up in the atmosphere between storms, the most acidic rain falls at the beginning of a storm, and as the rain continues, the acids "wash out" of the atmosphere.

  3. Acid Rain.

    ERIC Educational Resources Information Center

    Openshaw, Peter

    1987-01-01

    Provides some background information on acid deposition. Includes a historical perspective, describes some effects of acid precipitation, and discusses acid rain in the United Kingdom. Contains several experiments that deal with the effects of acid rain on water quality and soil. (TW)

  4. The Acid Rain Reader.

    ERIC Educational Resources Information Center

    Stubbs, Harriett S.; And Others

    A topic which is often not sufficiently dealt with in elementary school textbooks is acid rain. This student text is designed to supplement classroom materials on the topic. Discussed are: (1) "Rain"; (2) "Water Cycle"; (3) "Fossil Fuels"; (4) "Air Pollution"; (5) "Superstacks"; (6) "Acid/Neutral/Bases"; (7) "pH Scale"; (8) "Acid Rain"; (9)…

  5. Acid rain

    SciTech Connect

    Elsworth, S.

    1985-01-01

    This book was written in a concise and readable style for the lay public. It's purpose was to make the public aware of the damage caused by acid rain and to mobilize public opinion to favor the elimination of the causes of acid rain.

  6. Acid Rain

    MedlinePlus

    ... EPA Is Doing Acid Rain Program Cross-State Air Pollution Rule Progress Reports Educational Resources Kid's Site for ... Monitoring National Atmospheric Deposition Program (NADP) Exit Interstate Air Pollution Transport Contact Us to ask a question, provide ...

  7. Acid Rain

    USGS Publications Warehouse

    Bricker, Owen P.; Rice, Karen C.

    1993-01-01

    Acid deposition, or acid rain as it is more commonly referred to, has become a widely publicized environmental issue in the U.S. over the past decade. The term usually conjures up images of fish kills, dying forests, "dead" lakes, and damage to monuments and other historic artifacts. The primary cause of acid deposition is emission of S02 and NOx to the atmosphere during the combustion of fossil fuels. Oxidation of these compounds in the atmosphere forms strong acids - H2SO4 and HNO3 - which are returned to the Earth in rain, snow, fog, cloud water, and as dry deposition.Although acid deposition has only recently been recognized as an environmental problem in the U.S., it is not a new phenomenon (Cogbill & Likens 1974). As early as the middle of the 17th century in England, the deleterious effects of industrial emissions on plants, animals, and humans, and the atmospheric transport of pollutants between England and France had become issues of concern (Evelyn 1661, Graunt 1662). It is interesting that well over three hundred years ago in England, recommendations were made to move industry outside of towns and build higher chimneys to spread the pollution into "distant parts." Increasing the height of smokestacks has helped alleviate local problems, but has exacerbated others. In the U.S. the height of the tallest smokestack has more than doubled, and the average height of smokestacks has tripled since the 1950s (Patrick et al 1981). This trend occurred in most industrialized nations during the 20th century and has had the effect of transforming acid rain from a local urban problem into a problem of global scale.

  8. Acid Rain

    USGS Publications Warehouse

    Bricker, Owen P.; Rice, Karen C.; Dietrich, W.E.; Sposito, Garrison

    1997-01-01

    Acid deposition, or acid rain as it is more commonly referred to, has become a widely publicized environmental issue in the U.S. over the past decade. The term usually conjures up images of fish kills, dying forests, "dead" lakes, and damage to monuments and other historic artifacts. The primary cause of acid deposition is emission of S02 and NOx to the atmosphere during the combustion of fossil fuels. Oxidation of these compounds in the atmosphere forms strong acids - H2SO4 and HNO3 - which are returned to the Earth in rain, snow, fog, cloud water, and as dry deposition.Although acid deposition has only recently been recognized as an environmental problem in the U.S., it is not a new phenomenon (Cogbill & Likens 1974). As early as the middle of the 17th century in England, the deleterious effects of industrial emissions on plants, animals, and humans, and the atmospheric transport of pollutants between England and France had become issues of concern (Evelyn 1661, Graunt 1662). It is interesting that well over three hundred years ago in England, recommendations were made to move industry outside of towns and build higher chimneys to spread the pollution into "distant parts." Increasing the height of smokestacks has helped alleviate local problems, but has exacerbated others. In the U.S. the height of the tallest smokestack has more than doubled, and the average height of smokestacks has tripled since the 1950s (Patrick et al 1981). This trend occurred in most industrialized nations during the 20th century and has had the effect of transforming acid rain from a local urban problem into a problem of global scale.

  9. Acid rain

    SciTech Connect

    Sweet, W.

    1980-06-20

    Acid precipitation includes not only rain but also acidified snow, hail and frost, as well as sulfur and nitrogen dust. The principal source of acid precipitation is pollution emitted by power plants and smelters. Sulfur and nitrogen compounds contained in the emissions combine with moisture to form droplets with a high acid content - sometimes as acidic as vinegar. When sufficiently concentrated, these acids can kill fish and damage material structures. Under certain circumstances they may reduce crop and forest yields and cause or aggravate respiratory diseases in humans. During the summer, especially, pollutants tend to collect over the Great Lakes in high pressure systems. Since winds typically are westerly and rotate clockwise around high pressure systems, the pollutants gradually are dispersed throughout the eastern part of the continent.

  10. Acid rain

    SciTech Connect

    Not Available

    1984-06-01

    An overview is presented of acid rain and the problems it causes to the environment worldwide. The acidification of lakes and streams is having a dramatic effect on aquatic life. Aluminum, present in virtually all forest soils, leaches out readily under acid conditions and interferes with the gills of all fish, some more seriously than others. There is evidence of major damage to forests in European countries. In the US, the most severe forest damage appears to be in New England, New York's Adirondacks, and the central Appalachians. This small region is part of a larger area of the Northeast and Canada that appears to have more acid rainfall than the rest of the country. It is downwind from major coal burning states, which produce about one quarter of US SO/sub 2/ emissions and one sixth of nitrogen oxide emissions. Uncertainties exist over the causes of forest damage and more research is needed before advocating expensive programs to reduce rain acidity. The President's current budget seeks an expansion of research funds from the current $30 million per year to $120 million.

  11. Acid rain

    SciTech Connect

    Boyle, R.H.; Boyle, R.A.

    1983-01-01

    Acid rain, says Boyle is a chemical leprosy eating into the face of North America and Europe, perhaps the major ecological problem of our time. Boyle describes the causes and scope of the phenomenon; the effects on man, wildlife, water, and our cultural heritage. He probes the delays of politicians and the frequent self-serving arguments advanced by industry in the face of what scientists have proved. The solutions he offers are to strengthen the Clean Air Act and require emission reductions that can be accomplished by establishing emission standards on a regional or bubble basis, burn low-sulfur coal, install scrubbers at critical plants, and invest in alternative energy sources. 73 references, 1 figure.

  12. [Effects of simulated acid rain on respiration rate of cropland system with different soil pH].

    PubMed

    Zhu, Xue-zhu; Zhang, Gao-chuan; Li, Hui

    2009-10-15

    To evaluate the effects of acid rain on the respiration rate of cropland system, an outdoor pot experiment was conducted with paddy soils of pH 5.48 (S1), pH 6.70 (S1) and pH 8.18 (S3) during the 2005-2007 wheat-growing seasons. The cropland system was exposed to acid rain by spraying the wheat foliage and irrigating the soil with simulated rainwater of T1 (pH 6.0), T2 (pH 6.0, ionic concentration was twice as rainwater T1), and T3 (pH 4.4, ionic concentration was twice as rainwater T1), respectively. The static opaque chamber-gas chromatograph method was used to measure CO2 fluxes from cropland system. The results showed that acid rain affected the respiration rate of cropland system through crop plant, and the cropland system could adapt to acid rain. Acid rainwater significantly increased the average respiration rate in alkaline soil (S3) cropland system, while it had no significant effects on the average respiration rate in neutral soil (S2) and acidic soil (S1) cropland systems. During 2005-2006, after the alkaline soil cropland system was treated with rainwater T3, the average respiration rate was 23.6% and 27.6% higher than that of alkaline soil cropland system treated with rainwater T1 and T2, respectively. During March to April, the respiration rate was enhanced with the increase of rainwater ionic concentration, while it was dropped with the decrease of rainwater pH value in acidic soil cropland system. It was demonstrated that soil pH and crop plant played important roles on the respiration rate of cropland system.

  13. Effect of acid rain pH on leaching behavior of cement stabilized lead-contaminated soil.

    PubMed

    Du, Yan-Jun; Wei, Ming-Li; Reddy, Krishna R; Liu, Zhao-Peng; Jin, Fei

    2014-04-30

    Cement stabilization is a practical approach to remediate soils contaminated with high levels of lead. However, the potential for leaching of lead out of these stabilized soils under variable acid rain pH conditions is a major environmental concern. This study investigates the effects of acid rain on the leaching characteristics of cement stabilized lead contaminated soil under different pH conditions. Clean kaolin clay and the same soil spiked with 2% lead contamination are stabilized with cement contents of 12 and 18% and then cured for 28 days. The soil samples are then subjected to a series of accelerated leaching tests (or semi-dynamic leaching tests) using a simulated acid rain leachant prepared at pH 2.0, 4.0 or 7.0. The results show that the strongly acidic leachant (pH ∼2.0) significantly altered the leaching behavior of lead as well as calcium present in the soil. However, the differences in the leaching behavior of the soil when the leachant was mildly acidic (pH ∼4.0) and neutral (pH ∼7.0) prove to be minor. In addition, it is observed that the lead contamination and cement content levels can have a considerable impact on the leaching behavior of the soils. Overall, the leachability of lead and calcium is attributed to the stability of the hydration products and their consequent influence on the soil buffering capacity and structure.

  14. Understanding Acid Rain

    ERIC Educational Resources Information Center

    Damonte, Kathleen

    2004-01-01

    The term acid rain describes rain, snow, or fog that is more acidic than normal precipitation. To understand what acid rain is, it is first necessary to know what an acid is. Acids can be defined as substances that produce hydrogen ions (H+), when dissolved in water. Scientists indicate how acidic a substance is by a set of numbers called the pH…

  15. Acid Rain: An Educational Opportunity?

    ERIC Educational Resources Information Center

    Marion, James I.

    1984-01-01

    Deals with how educators can handle the subject of acid rain; illustrates suggestions with experiences of grade nine students visiting Frost Valley Environmental Education Center (Oliverea, New York) to learn scientific concepts through observation of outdoor phenomena, including a stream; and discusses acid rain, pH levels, and pollution control…

  16. Be an acid rain detective

    SciTech Connect

    Atwill, L.

    1982-07-01

    Acid rain is discussed in a question and answer format. The article is aimed at educating sport fishermen on the subject, and also to encourage them to write their congressmen, senators, and the President about the acid rain problem. The article also announces the availability of an acid rain test kit available through the magazine, ''Sports Afield.'' The kit consists of pH-test paper that turns different shades of pink and blue according to the pH of the water tested. The color of the test paper is then compared to a color chart furnished in the kit and an approximate pH can be determined.

  17. Acid Rain Study Guide.

    ERIC Educational Resources Information Center

    Hunger, Carolyn; And Others

    Acid rain is a complex, worldwide environmental problem. This study guide is intended to aid teachers of grades 4-12 to help their students understand what acid rain is, why it is a problem, and what possible solutions exist. The document contains specific sections on: (1) the various terms used in conjunction with acid rain (such as acid…

  18. USGS Tracks Acid Rain

    USGS Publications Warehouse

    Gordon, John D.; Nilles, Mark A.; Schroder, LeRoy J.

    1995-01-01

    The U.S. Geological Survey (USGS) has been actively studying acid rain for the past 15 years. When scientists learned that acid rain could harm fish, fear of damage to our natural environment from acid rain concerned the American public. Research by USGS scientists and other groups began to show that the processes resulting in acid rain are very complex. Scientists were puzzled by the fact that in some cases it was difficult to demonstrate that the pollution from automobiles and factories was causing streams or lakes to become more acidic. Further experiments showed how the natural ability of many soils to neutralize acids would reduce the effects of acid rain in some locations--at least as long as the neutralizing ability lasted (Young, 1991). The USGS has played a key role in establishing and maintaining the only nationwide network of acid rain monitoring stations. This program is called the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). Each week, at approximately 220 NADP/NTN sites across the country, rain and snow samples are collected for analysis. NADP/NTN site in Montana. The USGS supports about 72 of these sites. The information gained from monitoring the chemistry of our nation's rain and snow is important for testing the results of pollution control laws on acid rain.

  19. What Is Acid Rain?

    ERIC Educational Resources Information Center

    Likens, Gene E.

    2004-01-01

    Acid rain is the collective term for any type of acidified precipitation: rain, snow, sleet, and hail, as well as the presence of acidifying gases, particles, cloud water, and fog in the atmosphere. The increased acidity, primarily from sulfuric and nitric acids, is generated as a by-product of the combustion of fossil fuels such as coal and oil.…

  20. Acidification and Acid Rain

    NASA Astrophysics Data System (ADS)

    Norton, S. A.; Veselã½, J.

    2003-12-01

    endangers the existing biota. Concerns about acid (or acidic) rain in its modern sense were publicized by the Swedish soil scientist Svante Odén (1968). He argued, initially in the Swedish press, that long-term increases in the atmospheric deposition of acid could lower the pH of surface waters, cause a decline in fish stocks, deplete soils of nutrients, and accelerate damage to materials. By the 1970s, acidification of surface waters was reported in many countries in Europe as well as in North America. The late twentieth-century rush to understand the impact of acid rain was driven by: (i) reports of damaged or threatened freshwater fisheries and (ii) damaged forests. Perhaps the earliest linkage between acidic surface water and damage to fish was made by Dahl (1921) in southern Norway. There, spring runoff was sufficiently acidic to kill trout. It was not until the 1970s that a strong link was established between depressed pH, mobilization of aluminum from soil, and fish status ( Schofield and Trojnar,1980). The relationship between acidification of soils and forest health started with hypotheses in the 1960s and has slowly developed. Acid rain enhances the availability of some nutrients (e.g., nitrogen), and may either enhance or diminish the availability of others (e.g., calcium, magnesium, potassium, and phosphorus). Damage to anthropogenic structures, human health, and visibility have also raised concerns. The history of these early developments was summarized by Cowling (1982). Since the 1970s, sulfur and nitrogen emissions to the atmosphere have been reduced by 50-85% and 0-30%, respectively, both in North America and Europe. The emission reductions have occurred as a consequence of knowledge gained and economic factors. While recovery of water quality is underway in some areas, problems of acidification persist, and are now complicated by the effects of climate change ( Schindler, 1997).

  1. Difficult Decisions: Acid Rain.

    ERIC Educational Resources Information Center

    Miller, John A.; Slesnick, Irwin L.

    1989-01-01

    Discusses some of the contributing factors and chemical reactions involved in the production of acid rain, its effects, and political issues pertaining to who should pay for the clean up. Supplies questions for consideration and discussion. (RT)

  2. Acid Rain. LC Science Tracer Bullet.

    ERIC Educational Resources Information Center

    Hollmann, Pauline, Comp.

    The term "acid rain," also called "acid precipitation," generally refers to any precipitation having a pH value of less than 5.6. This guide to the literature on acid rain in the collections of the Library of Congress is not necessarily intended to be a comprehensive bibliography. It is designed to provide the reader with a set…

  3. Nickel toxicity to microbes: effect of pH and implications for acid rain

    SciTech Connect

    Babich, H.; Stotzky, G.

    1982-12-01

    A broad spectrum of microorganisms, including eubacteria (nonmarine and marine), actinomycetes, yeasts, and filamentous fungi, were evaluated for their sensitivities to nickel. Wide extremes in sensitivity to Ni were noted among the filamentous fungi, whereas the range of tolerance to Ni of the yeasts, eubacteria, and actinomycetes was narrower. With all microorganisms, the toxicity of Ni has not been defined, although the formation of hydroxylated Ni species with differing toxicities was not involved. The enhanced toxicity of Ni at acidic levels may have implications for the toxicity of Ni in environments stressed by acid precipitation.

  4. Effects of acid rain on grapevines

    SciTech Connect

    Forsline, P.L.; Musselman, R.C.; Dee, R.J.; Kender, W.J.

    1983-01-01

    Mature vineyard-growing Concord grapevines (Vitis labrusca, Bailey) were sprayed with simulated acid rain solutions ranging from pH 2.5 to pH 5.5 both as acute treatments at anthesis and chronically throughout the season in 1980 and 1981. In 1981, eight additional varieties were also treated with simulated acid rain solutions at pH 2.75 and pH 3.25. With Concord in 1981, few foliar lesions on leaves were visible at pH 2.75. In contrast, many leaf lesions with decreased fruit soluble solids in the absence of acid rain leaf lesions at pH>2.5 remains unclear. Acute sprays (pH 2.75) at anthesis reduced pollen germination in four grape cultivars. However, fruit set was reduced in only one of these. Only the cultivars de Chaunac and Ives had reduced berry soluble solids with chronic weekly sprays at pH 2.75. Reduction in soluble solids was not associated with increased oxidant stipple (ozone injury) in Concord and de Chaunac cultivars, but this association was observed in Ives. There was no evidence that acid rain in combination with ozone increased oxidant stipple as occurs when ozone and SO/sub 2/ are combined. Grape yields were not influenced by acid rain treatments. There was no evidence that acid rain at ambient pH levels had negative effects on grape production or fruit quality.

  5. The Acid Rain Debate.

    ERIC Educational Resources Information Center

    Oates-Bockenstedt, Catherine

    1997-01-01

    Details an activity designed to motivate students by incorporating science-related issues into a classroom debate. Includes "The Acid Rain Bill" and "Position Guides" for student roles as committee members, consumers, governors, industry owners, tourism professionals, senators, and debate directors. (DKM)

  6. Acid Rain Investigations.

    ERIC Educational Resources Information Center

    Hugo, John C.

    1992-01-01

    Presents an activity in which students investigate the formation of solid ammonium chloride aerosol particles to help students better understand the concept of acid rain. Provides activity objectives, procedures, sample data, clean-up instructions, and questions and answers to help interpret the data. (MDH)

  7. The Acid Rain Game.

    ERIC Educational Resources Information Center

    Rakow, Steven J.; Glenn, Allen

    1982-01-01

    Provides rationale for and description of an acid rain game (designed for two players), a problem-solving model for elementary students. Although complete instructions are provided, including a copy of the game board, the game is also available for Apple II microcomputers. Information for the computer program is available from the author.…

  8. Acid Rain Classroom Projects.

    ERIC Educational Resources Information Center

    Demchik, Michael J.

    2000-01-01

    Describes a curriculum plan in which students learn about acid rain through instructional media, research and class presentations, lab activities, simulations, design, and design implementation. Describes the simulation activity in detail and includes materials, procedures, instructions, examples, results, and discussion sections. (SAH)

  9. The Acid Rain Debate.

    ERIC Educational Resources Information Center

    Bybee, Rodger; And Others

    1984-01-01

    Describes an activity which provides opportunities for role-playing as industrialists, ecologists, and government officials. The activity involves forming an international commission on acid rain, taking testimony, and, based on the testimony, making recommendations to governments on specific ways to solve the problem. Includes suggestions for…

  10. Acid rain bibliography

    SciTech Connect

    Sayers, C.S.

    1983-09-01

    This bibliography identifies 900 citations on various aspects of Acid Rain, covering published bibliographies, books, reports, conference and symposium proceedings, audio visual materials, pamphlets and newsletters. It includes five sections: citations index (complete record of author, title, source, order number); KWIC index; title index; author index; and source index. 900 references.

  11. Acid rain sourcebook

    SciTech Connect

    Elliott, T.C.; Schwieger, R.G.

    1984-01-01

    Discusses the problem of acid rain and how it can be controlled. The book is divided into seven key sections: the problem and the legislative solutions; international mitigation programs; planning the US program; emissions reduction-before combustion; emissions/reduction-during combustion; emissions reduction-after combustion and engineering solutions under development. 13 papers have been abstracted separately.

  12. The acid rain sourcebook

    SciTech Connect

    Elliott, T.C.; Schwieger, R.G.

    1985-01-01

    A reference collection of specialized information discussions on areas critical to the acid rain issue: problem definition, impact of legislation, emissions standards, international perspective, cost scenarios, and engineering solutions. The text is reinforced with 130 illustrations and about 50 tables. Contents: International mitigation programs. Emissions reduction: before combustion; during combustion; after combustion. Engineering solutions under development.

  13. Effects of acid rain on grapevines

    SciTech Connect

    Forsline, P.L.; Musselman, R.C.; Dee, R.J.; Kender, W.J.

    1983-01-01

    Mature vineyard-growing Concord grapevines were sprayed with simulated acid rain solutions ranging from pH 2.5 to 5.5 both as acute treatments at anthesis and chronically throughout the season in 1980 and 1981. In 1981, 8 additional varieties were also treated with simulated acid rain solutions at pH 2.75 and 3.25. With Concord in 1981, few foliar lesions on leaves were visible at pH 2.75. In contrast, many leaf lesions with decreased fruit soluble solids were observed at pH 2.5 in 1980. The relationship between acid-rain and oxidant stipple, chlorosis, and soluble solids in the absence of acid rain leaf lesions at pH>2.5 remains unclear. Acute sprays (pH2.75) at anthesis reduced pollen germination in four grape cultivars. However, fruit set was reduced in only one of these. Grape yields were not influenced by acid rain treatments. There was no evidence that acid-rain at ambient pH levels had negative effects on grape production or fruit quality.

  14. The politics of acid rain

    SciTech Connect

    Wilcher, M.E. )

    1989-01-01

    This work examines and compares the acid rain policies through the different political systems of Canada, Great Britain and the United States. Because the flow of acid rain can transcend national boundaries, acid rain has become a crucial international problem. According to the author, because of differences in governmental institutions and structure, the extent of governmental intervention in the industrial economy, the degree of reliance on coal for power generation, and the extent of acid rain damage, national responses to the acid rain problem have varied.

  15. A Demonstration of Acid Rain

    ERIC Educational Resources Information Center

    Fong, Man Wai

    2004-01-01

    A demonstration showing acid rain formation is described. Oxides of sulfur and nitrogen that result from the burning of fossil fuels are the major pollutants of acid rain. In this demonstration, SO[subscript 2] gas is produced by the burning of matches. An acid-base indicator will show that the dissolved gas turns an aqueous solution acidic.

  16. Acid rain in Asia

    NASA Astrophysics Data System (ADS)

    Bhatti, Neeloo; Streets, David G.; Foell, Wesley K.

    1992-07-01

    Acid rain has been an issue of great concern in North America and Europe during the past several decades. However, due to the passage of a number of recent regulations, most notably the Clean Air Act in the United States in 1990, there is an emerging perception that the problem in these Western nations is nearing solution. The situation in the developing world, particularly in Asia, is much bleaker. Given the policies of many Asian nations to achieve levels of development comparable with the industrialized world—which necessitate a significant expansion of energy consumption (most derived from indigenous coal reserves)—the potential for the formation of, and damage from, acid deposition in these developing countries is very high. This article delineates and assesses the emissions patterns, meteorology, physical geology, and biological and cultural resources present in various Asian nations. Based on this analysis and the risk factors to acidification, it is concluded that a number of areas in Asia are currently vulnerable to acid rain. These regions include Japan, North and South Korea, southern China, and the mountainous portions of Southeast Asia and southwestern India. Furthermore, with accelerated development (and its attendant increase in energy use and production of emissions of acid deposition precursors) in many nations of Asia, it is likely that other regions will also be affected by acidification in the near future. Based on the results of this overview, it is clear that acid deposition has significant potential to impact the Asian region. However, empirical evidence is urgently needed to confirm this and to provide early warning of increases in the magnitude and spread of acid deposition and its effects throughout this part of the world.

  17. An Umbrella for Acid Rain.

    ERIC Educational Resources Information Center

    Randal, Judith

    1979-01-01

    The Environmental Protection Agency has awarded several grants to study effects of and possible solutions to the problem of "acid rain"; pollution from atmospheric nitric and sulfuric acids. The research program is administered through North Carolina State University at Raleigh and will focus on biological effects of acid rain. (JMF)

  18. Acid rain threatens marine life

    SciTech Connect

    Not Available

    1988-09-01

    In freshwater, acid rain harms aquatic organisms because one of its components, sulfur dioxide, lowers the water's pH. In seawater, the damage comes from other components of acid precipitation: nitrogen oxides. Acting as a nutrient, nitrogen promotes excessive algal growth, which blocks sunlight and depletes dissolved oxygen, thereby suffocating other plants and animals. Known as eutrophication, this phenomenon has been increasing in both frequency and intensity on the Atlantic coast during the past few years. The New York City-based Environmental Defense Fund (EDF), study focused on the Chesapeake Bay, the nation's largest estuary and an important spawning ground for many species of economic importance. It has long been known that the bay is suffering from nitrogen pollution. Until now, it was assumed that most of the nitrogen was coming from sewage and agricultural runoff. However, based on data collected from both federal and state agencies, EDF scientists estimated that nitrates from acid rain are responsible for 25% of the nitrogen entering the bay. The report says that if present trends continue, airborne nitrates will contribute 42% of annual nitrogen deposits into the Chesapeake Bay by the year 2030.

  19. Acid Rain: What's the Forecast?

    ERIC Educational Resources Information Center

    Bybee, Rodger

    1984-01-01

    Discusses various types of acid rain, considered to be a century-old problem. Topics include: wet and dry deposition, effects on a variety of environments, ecosystems subject to detrimental effects, and possible solutions to the problem. A list of recommended resources on acid rain is provided. (BC)

  20. Acid rain & electric utilities II

    SciTech Connect

    1997-12-31

    This document presents reports which were presented at the Acid Rain and Electric Utilities Conference. Topics include environmental issues and electric utilities; acid rain program overview; global climate change and carbon dioxide; emissions data management; compliance; emissions control; allowance and trading; nitrogen oxides; and assessment. Individual reports have been processed separately for the United States Department of Energy databases.

  1. Acid Rain: The Scientific Challenge.

    ERIC Educational Resources Information Center

    Godfrey, Paul J.

    1991-01-01

    Documents the workings and findings of the Massachusetts Acid Rain Monitoring Project, which has pooled the volunteer efforts of more than 1,000 amateur and professional scientists since 1983. Reports on the origins of air pollution, the prediction of acid rain, and its effects on both water life and land resources. (JJK)

  2. Rain pH estimation based on the particulate matter pollutants and wet deposition study.

    PubMed

    Singh, Shweta; Elumalai, Suresh Pandian; Pal, Asim Kumar

    2016-09-01

    In forecasting of rain pH, the changes caused by particulate matter (PM) are generally neglected. In regions of high PM concentration like Dhanbad, the role of PM in deciding the rain pH becomes important. Present work takes into account theoretical prediction of rain pH by two methods. First method considers only acid causing gases (ACG) like CO2, SO2 and NOx in pH estimation, whereas, second method additionally accounts for effect of PM (ACG-PM). In order to predict the rain pH, site specific deposited dust that represents local PM was studied experimentally for its impact on pH of neutral water. After incorporation of PM correction factor, it was found that, rain pH values estimated were more representative of the observed ones. Fractional bias (FB) for the ACG-PM method reduced to values of the order of 10(-2) from those with order of 10(-1) for the ACG method. The study confirms neutralization of rain acidity by PM. On account of this, rain pH was found in the slightly acidic to near neutral range, despite of the high sulfate flux found in rain water. Although, the safer range of rain pH blurs the severity of acid rain from the picture, yet huge flux of acidic and other ions get transferred to water bodies, soil and ultimately to the ground water system. Simple use of rain pH for rain water quality fails to address the issues of its increased ionic composition due to the interfering pollutants and thus undermines severity of pollutants transferred from air to rain water and then to water bodies and soil.

  3. Can crops tolerate acid rain

    SciTech Connect

    Kaplan, J.K.

    1989-11-01

    This brief article describes work by scientists at the ARS Air Quality-Plant Growth and Development Laboratory in Raleigh, North Carolina, that indicates little damage to crops as a result of acid rain. In studies with simulated acid rain and 216 exposed varieties of 18 crops, there were no significant injuries nor was there reduced growth in most species. Results of chronic and acute exposures were correlated in sensitive tomato and soybean plants and in tolerant winter wheat and lettuce plants. These results suggest that 1-hour exposures could be used in the future to screen varieties for sensitivity to acid rain.

  4. Acid rain and its ecological consequences.

    PubMed

    Singh, Anita; Agrawal, Madhoolika

    2008-01-01

    Acidification of rain-water is identified as one of the most serious environmental problems of transboundary nature. Acid rain is mainly a mixture of sulphuric and nitric acids depending upon the relative quantities of oxides of sulphur and nitrogen emissions. Due to the interaction of these acids with other constituents of the atmosphere, protons are released causing increase in the soil acidity Lowering of soil pH mobilizes and leaches away nutrient cations and increases availability of toxic heavy metals. Such changes in the soil chemical characteristics reduce the soil fertility which ultimately causes the negative impact on growth and productivity of forest trees and crop plants. Acidification of water bodies causes large scale negative impact on aquatic organisms including fishes. Acidification has some indirect effects on human health also. Acid rain affects each and every components of ecosystem. Acid rain also damages man-made materials and structures. By reducing the emission of the precursors of acid rain and to some extent by liming, the problem of acidification of terrestrial and aquatic ecosystem has been reduced during last two decades.

  5. Acid Thunder: Acid Rain and Ancient Mesoamerica

    ERIC Educational Resources Information Center

    Kahl, Jonathan D. W.; Berg, Craig A.

    2006-01-01

    Much of Mesoamerica's rich cultural heritage is slowly eroding because of acid rain. Just as water dissolves an Alka-Seltzer tablet, acid rain erodes the limestone surfaces of Mexican archaeological sites at a rate of about one-half millimeter per century (Bravo et al. 2003). A half-millimeter may not seem like much, but at this pace, a few…

  6. Atmospheric dust and acid rain

    SciTech Connect

    Hedin, L.O.; Likens, G.E.

    1996-12-01

    Why is acid rain still an environmental problem in Europe and North America despite antipollution reforms? The answer really is blowing in the wind: atmospheric dust. These airborne particles can help neutralize the acids falling on forests, but dust levels are unusually low these days. In the air dust particles can neutralize acid rain. What can we do about acid rain and atmospheric dust? Suggestions range from the improbable to the feasible. One reasonable suggestion is to reduce emissions of acidic pollutants to levels that can be buffered by natural quantities of basic compounds in the atmosphere; such a goal would mean continued reductions in sulfur dioxide and nitrogen oxides, perhaps even greater than those prescribed in the 1990 Amendments to the Clean Air Act in the U.S. 5 figs.

  7. Geographical distribution and temporal variation of rain acidity over China

    SciTech Connect

    Wen-Xing Wang; Yan-Bo Pang; Guo-An Ding

    1996-12-31

    In recent decade, large areas of acid rain have appeared in China. With the increasing emission of SO{sub 2} and NO{sub x} year by year, the acidity of precipitation has increased, and the acid rain area is expanding. Presently, the acid rain in China has become the third largest area of acid rain in the world, next to Europe and North America. The Chinese government took action against acid rain and planned a five-year National Acid Deposition Research Project. The space-time distribution and variation of rain acidity described in this paper is a part of this project. China is a large country. The area is almost equal to that of Europe. Its climate varies greatly and spans the tropics, subtropics, temperate and frigid zone. There is a varied topography including mountain, hilly country, desert and plain, on the other hand the distribution of anthropogenic sources are not even. All of the human and natural factors caused different chemical composition in different parts of China, the acidity of precipitation varies also. The acidity of the precipitation is the most important parameter in the acid rain research. In order to obtain the regional representative distribution of rain acidity, National Acidic Deposition Research Monitoring Network with 261 monitoring sites was established in 1992. This paper summarizes the rain acidity of 21355 precipitation samples, and gave the annual, seasonal, and the monthly pH contours. Results show that the acid rain area has expanded from the south during winter. Regional differences of monthly acid precipitation exists, generally, the rain acidity level is higher during summer and fall and lower during winter and spring in the northern provinces. The 9 opposite is the case in the southern provinces. The central areas are in a transitional situation. The geographical distribution and temporal variation of rain acidity are quite different from North America and Europe.

  8. THE ACID RAIN NOX PROGRAM

    EPA Science Inventory

    Between 350,000 and 400,000 tons of annual NOx emissions have been eliminated as a result of Phase I of the Acid Rain NOx Program. As expected. the utilities have chosen emissions averaging as the primary compliance option. This reflects that, in general, NO x reductions have ...

  9. Nature in the Classroom: Acid Rain.

    ERIC Educational Resources Information Center

    Doyle, Charles

    1982-01-01

    As a lesson topic, acid rain is defined, its chemistry given, and its development since the 1950s described. The worldwide effects of acid rain are discussed along with the available technology for controlling the problem. (CM)

  10. Acid Rain: The Silent Environmental Threat.

    ERIC Educational Resources Information Center

    Zmud, Mia

    1992-01-01

    Describes the silent environmental threat posed by acid rain. Caused mainly by manmade pollutants, acid rain damages water and trees, decreases visibility, corrodes monuments, and threatens public health. The article includes guidelines for action. (SM)

  11. Acid Rain Program Opt-in Factsheet

    EPA Pesticide Factsheets

    Learn about the Opt-in Program, which allows sources not required to participate in the Acid Rain Program the opportunity to enter the program on a voluntary basis and receive Acid Rain Program allowances.

  12. Acid rain control: the costs of compliance

    SciTech Connect

    Gilleland, D.S.; Swisher, J.H.

    1985-01-01

    This document is the proceedings from a conference sponsored by the Illinois Energy Resources Commission and the Coal Extraction and Utilization Research Center, Southern Illinois University at Carbondale and held in Carbondale on March 18, 1984. Topics addressed include: the sources and impacts of acid rain, the problems inherent in modeling the impacts of acid rain legislation, the effects of acid rain legislation on the socio-economic sector, compliance costs, and the impact of acid rain legislation on related industries (railroads).

  13. [Relationship between simulated acid rain stress and leaf reflectance].

    PubMed

    Song, Xiao-dong; Jiang, Hong; Yu, Shu-quan; Zhou, Guo-mo; Jiang, Zi-shan

    2010-01-01

    Acid rain is a worldwide environmental problem. Serious acid rain pollution in subtropical China has constituted a potential threat to the health of the local forest. In the present paper, the changing properties of the chlorophyll concentration and spectral reflectance at the visible wavelengths for the six subtropical broad-leaved tree species leaves under simulated acid rain (SAR) treatment with different pH levels were studied. With the increasing strength of the SAR, the chlorophyll concentrations of the experimental species under pH 2.5 and pH 4.0 treatment were higher than that under pH 5.6; the spectral reflectance at the visible wavelengths for pH 2.5 and pH 4.0 were lower than that for pH 5.6 in general; while there weren't significant differences between pH 2.5 and pH 4.0. After the treatment with different levels of SAR, the differences in spectral reflectance at the visible wavelengths mainly focused around the green peak and red edge on the reflectance curve. The subtropical broad-leaved tree species studied were relatively not sensitive to acid rain stresses; some stronger acid rain may accelerate the growth of the tree species used here to some extent.

  14. Acid Rain: What We Must Do.

    ERIC Educational Resources Information Center

    Gorham, Eville

    1983-01-01

    Addresses questions about the nature, source, and history of acid rain. In addition, discusses the questions: Why is acid rain a problem? Is acid rain getting worse? What is the threat of further problems? Concludes that it is time to act on the problem and recommends an appropriate course of action. (JN)

  15. Acid Rain: What It Is -- How You Can Help!

    ERIC Educational Resources Information Center

    National Wildlife Federation, Washington, DC.

    This publication discusses the nature and consequences of acid precipitation (commonly called acid rain). Topic areas include: (1) the chemical nature of acid rain; (2) sources of acid rain; (3) geographic areas where acid rain is a problem; (4) effects of acid rain on lakes; (5) effect of acid rain on vegetation; (6) possible effects of acid rain…

  16. Response of soybean seed germination to cadmium and acid rain.

    PubMed

    Liu, Ting Ting; Wu, Peng; Wang, Li Hong; Zhou, Qing

    2011-12-01

    Cadmium (Cd) pollution and acid rain are the main environmental issues, and they often occur in the same agricultural region. Nevertheless, up to now, little information on the combined pollution of Cd(2+) and acid rain action on crops were presented. Here, we investigated the combined effect of Cd(2+) and acid rain on the seed germination of soybean. The results indicated that the single treatment with the low level of Cd(2+) (0.18, 1.0, 3.0 mg L(-1)) or acid rain (pH ≥3.0) could not affect the seed germination of soybean, which was resulted in the increased activities of peroxidase and catalase. The single treatment with the high concentration of Cd(2+) (>6 mg L(-1)) or acid rain at pH 2.5 decreased the activities of peroxidase and catalase, damaged the cell membrane and then decreased the seed germination of soybean. Meanwhile, the same toxic effect was observed in the combined treatment with Cd(2+) and acid rain, and the combined treatment had more toxic effect than the single treatment with Cd(2+) or acid rain. Thus, the combined pollution of Cd(2+) and acid rain had more potential threat to the seed germination of soybean than the single pollution of Cd(2+) or acid rain.

  17. Field evaluation of an acid rain-drought stress interaction.

    PubMed

    Banwart, W L

    1988-01-01

    Various methods have been proposed to simulate natural field conditions for growing agricultural crops while controlling conditions to study specific environmental effects. This report briefly describes the use of moveable rain exclusion shelters (10.4 x 40.9 m) to study the results of the interaction of acid rain and drought stress on corn and soybean yields. The rain exclusion shelters are constructed of galvanized pipe framing and covered with polyethylene film. Movement is automated by a rain switch to protect crops from ambient rainfall and to treat them with simulated acid rain The facility simulates a real environment with respect to variables such as solar exposure, wind movement, dew formation, and insect exposure, while allowing careful control of moisture regimes. Soybeans and corn were treated with average rainfall amounts, and with one-half and one-quarter of these rainfall amounts (drought stress) at two levels of rainfall acidity, pH 5.6 and 3.0. While drought stress resulted in considerable yield reduction for Amsoy and Williams soybeans, no additional reduction in yield was observed with rainfall of pH 3.0, as compared to rainfall of approximately pH 5.6. Similar results were observed for one corn cultivar, Pioneer 3377. For one year of the study however, yield of B73 x Mo17 (corn) was reduced 3139 kg ha(-1) by the most severe drought, and an additional 1883 kg ha(-1) by acid rain of pH 3.0, as compared to the control (pH 5.6). Yield reduction from acidic rain was considerably less at full water rates, resulting in a significant pH by drought stress interaction. However, during the second year of the experiment, no pH effect or drought by pH interaction was observed for this cultivar. The reason for the difference in the two years was not identified.

  18. Acid rain. Rhetoric and reality

    SciTech Connect

    Park, C.

    1988-01-01

    The book examines the implications of recent scientific studies, and sets the political debate in the main 'polluting' countries--Britain and the United States--into its proper international context. It provides a wealth of U.S. data, including a history of the development of U.S. acid rain policy. The author presents a review of the evidence for damage and the statistics of change. Data is drawn from around the world, with particular emphasis on damage in Scandinavia and West Germany.

  19. [Effects of simulated acid rain on water physiological characteristics of Myrica rubra seedlings].

    PubMed

    Yaho, Zhao-bin; Jiang, Hong; Yu, Shu-quan; Lu, Mei-juan

    2011-08-01

    Taking the seedlings of typical subtropical economic tree species Myrica rubra in Zhejiang Province as test materials, a pot experiment was conducted to study their water physiological characteristics under effects of simulated acid rain (pH 2.5 and pH 4.0), with water (pH 5.6) as the control. Season, year, and acid rain all had significant effects on the photosynthetic rate (Pn). Among the treatments, the Pn had a greater difference in summer than in spring and autumn, and was higher in treatment acid rain (pH 4.0). Season, year, acid rain, and the interactions of season and year and of the three factors had significant effects on the stomata conductance (Gs), and also, the Gs had a greater difference among the treatments in summer than in spring and autumn. Acid rain had inhibitory effect on Gs. Season, year, acid rain, and the interactions of season and year and of season and acid rain affected the transpiration rate (Tr) significantly. Same as Pn and Gs, the Tr had a greater difference among the treatments in summer than in spring and autumn. Acid rain (pH 2.5) had the strongest inhibitory effect on Tr. Acid rain and the interactions of season and year and of season and acid rain had significant effects on the water use efficiency (WUE), and acid rain (pH 2.5) had definitely positive effect on the WUE.

  20. Two groups challenge US acid rain efforts

    SciTech Connect

    Not Available

    1987-11-01

    In its report, Acid Rain Invades Our National Parks, the National Parks and Conservation Association (NPCA) says acid rain is being detected at all 27 national park monitoring sites. In 1980, 87 national parks expressed concern in a NPCA survey over acid rain. Repolled in 1986, more than half of the respondents reported that no research on acid rain was under way. The NPCA report concludes that the alarm that was sounded in 1980 fell largely on deaf ears, and calls for the structural and scientific reorganization of the National Park Service. The National Audubon Society shares NPCA's dissatisfaction with federal efforts to tackle the problem of acid rain and has taken testing into its own hands. Through its Citizens Acid Rain Monitoring Network, Audubon volunteers have collected readings of acidity at 64 monitoring stations in 31 states since July.

  1. Activity of earthworm in Latosol under simulated acid rain stress.

    PubMed

    Zhang, Jia-En; Yu, Jiayu; Ouyang, Ying

    2015-01-01

    Acid rain is still an issue of environmental concerns. This study investigated the impacts of simulated acid rain (SAR) upon earthworm activity from the Latosol (acidic red soil). Laboratory experiment was performed by leaching the soil columns grown with earthworms (Eisenia fetida) at the SAR pH levels ranged from 2.0 to 6.5 over a 34-day period. Results showed that earthworms tended to escape from the soil and eventually died for the SAR at pH = 2.0 as a result of acid toxicity. The catalase activity in the earthworms decreased with the SAR pH levels, whereas the superoxide dismutases activity in the earthworms showed a fluctuate pattern: decreasing from pH 6.5 to 5.0 and increasing from pH 5.0 to 4.0. Results implied that the growth of earthworms was retarded at the SAR pH ≤ 3.0.

  2. Acid rain information book. Draft final report

    SciTech Connect

    1980-12-01

    Acid rain is one of the most widely publicized environmental issues of the day. The potential consequences of increasingly widespread acid rain demand that this phenomenon be carefully evaluated. Reveiw of the literature shows a rapidly growing body of knowledge, but also reveals major gaps in understanding that need to be narrowed. This document discusses major aspects of the acid rain phenomenon, points out areas of uncertainty, and summarizes current and projected research by responsible government agencies and other concerned organizations.

  3. Acid Rain Students Do Original Research.

    ERIC Educational Resources Information Center

    Outdoor Communicator, 1984

    1984-01-01

    At Park Senior High School (Cottage Grove, Minnesota), 46 juniors and seniors planted 384 red pine seedlings in connection with their original research on acid rain, with advice from Dr. Harriet Stubbs, director of the Acid Precipitation Awareness Program (West Saint Paul), which has been developing acid rain teaching materials. (MH)

  4. Effect of acid rain on the growth and nutrient content of two species of hardwood tree seedlings, and on the pH, microflora and nutrient content of the soil

    SciTech Connect

    Patten, D.K.

    1983-01-01

    The purpose of this study was to determine the sensitivity of two hardwood tree species and three soils to simulated acid rain. The value of infecting tree seedlings with mycorrhizal fungi before transplanting into acid-leached soils was also examined. Dundas silt loam, Hayden loam and Luther loam supporting coleus and sorghum were leached three times each week for 20 weeks with a mixture of H/sub 2/SO/sub 4/ and HNO/sub 3/ adjusted by dilution to pH 5.5, 4.0 or 2.5 Ninety seedlings each of green ash (Fraxinus pennsylvanica Marsh.) and silver maple (Acer saccharinum L.) were transplanted into the soils and were misted twice weekly with the acid solutions. Ash seedlings misted with the pH 2.5 solution were shorter, had a smaller total leaf area and produced less leaf and stem material than ash seedlings misted wth pH 5.5 solution. In contrast, the growth and weight of the maple seedlings increased in response to the pH 2.5 treatments. Leaves of the ash exposed to the pH 2.5 treatment were covered with numerous small lesions, and the cuticular wax was partially worn away. Nitrogen concentrations in the leaves, stems and roots of both species increased with increasing acidity, while phosphorus concentration in the leaves decreased. Soils became increasingly acidic as the acid treatments continued.

  5. Pollen selection under acid rain stress

    SciTech Connect

    Zhang, Y.

    1994-01-01

    To investigate whether acid rain stress induces pollen selection in nature, three different approaches were used, based on the assumption that the response of pollen grains to acid rain is controlled by an acid sensitive gene product. Germination of pollen from homozygous and heterozygous individuals under acid rain stress was examined to detect any differences in rate of germination between populations of homogeneous and heterogeneous pollen grains. In vitro and in vivo bulked segregant analysis using RAPDs was used to search for differences in DNA constitution between the survivors of acid rain stressed and non-acid rain stressed pollen populations in vitro and between the progenies of acid rain stressed and non-acid rain stressed populations during pollination, respectively. No evidence for the pollen selection under acid rain stress was obtained in any of the test systems. Inhibition of protein synthesis using cycloheximide led to significant reduction of tube elongation at 4 hr and had no effect on pollen germination at any time interval tested. Total proteins extracted from control and acid rain stressed pollen grain populations exhibited no differences. The reduction of corn pollen germination in vitro under acid rain stress was mainly due to pollen rupture. The present data indicates the reduction of pollen germination and tube growth under acid rain stress may be a physiological response rather than a genetic response. A simple, nontoxic, and effective method to separate germinated from ungerminated pollen grains has been developed using pollen from corn (Zea mays, L. cv. Pioneer 3747). The separated germinated pollen grains retained viability and continued tube growth when placed in culture medium.

  6. Acid soil and acid rain, 2nd edition

    SciTech Connect

    Kennedy, I.R.

    1992-01-01

    This book examines the basic chemical processes involved in acidification in order to better assess their long-term effects on the status of soils, the health of plants and other living species that depend on them. It also discusses acidity, pH and protons their significance in bioenergetics and the consequent role of autotrophic organisms in acidifying ecosystems. This edition incorporates and integrates recent findings that render more explanations of the causes of the environmental impacts of acidity, especially in forests and lakes. Also explores current research into acid rain and soil in order to devise appropriate measures for their amelioration.

  7. Human Ecology: Acid Rain and Public Policy.

    ERIC Educational Resources Information Center

    Bybee, Rodger W.

    1983-01-01

    A connection between science and society can be seen in the human and ecological dimensions of one contemporary problem: acid rain. Introduces a human ecological theme and relationships between acid rain and public policy, considering scientific understanding and public awareness, scientific research and public policy, and national politics and…

  8. Acid Rain: Activities for Science Teachers.

    ERIC Educational Resources Information Center

    Johnson, Eric; And Others

    1983-01-01

    Seven complete secondary/college level acid rain activities are provided. Activities include overview; background information and societal implications; major concepts; student objectives; vocabulary/material lists; procedures; instructional strategies; and questions/discussion and extension suggestions. Activities consider effects of acid rain on…

  9. CR@BaSO4: an acid rain-indicating material.

    PubMed

    Gao, Hong-Wen; Xu, Xin-Hui

    2011-12-28

    The CR@BaSO(4) hybrid was synthesized, characterized and used as an acid rain-indicating (ARI) material. A painted ARI umbrella was discolored after exposure to simulated acid rain of pH 5 or less and returned to the initial color after the rain stopped. Such a functionalized material may make acid rain visual to remind people in real-time.

  10. Acid Rain: A Teaching Focus for the Intermediate Grades.

    ERIC Educational Resources Information Center

    Adams, Renee B.; Adams, Neil D.

    1992-01-01

    The study of acid rain provides ample opportunities for active, interdisciplinary learning. This article describes 12 hands-on activities designed to expand students' understanding of acid rain. Background information on acid rain is included. (LB)

  11. Acid rain attack on outdoor sculpture in perspective

    NASA Astrophysics Data System (ADS)

    Livingston, Richard A.

    2016-12-01

    A major concern motivating research in acid rain materials effects has been the potential for damage to cultural heritage, particularly outdoor marble and bronze sculpture. However, a combination of field and laboratory studies has failed to show a correlation between rain pH and loss of materials. In order to understand this counterintuitive lack of acid rain effect, an aqueous geochemical modeling approach was used to analyze rain runoff chemistry for the relative importance of acid rain neutralization, dry deposition, and in the case of marble, natural carbonate dissolution. This approach involved the development of pH - SO42- phase diagrams for marble (calcium carbonate) and bronze (copper) under ambient environmental conditions. This then enabled reaction path modeling of the acid neutralization process using the pH range typically found in wet deposition (3.5-6). The results were for marble that the theoretical maximum amount of Ca2+ ion that could be lost due acid rain neutralization would be 0.158 mmol/l compared to 10.5 mmol/l by dry deposition, and for bronze, the Cu2+ ion losses would be 0.21 mmol/l and 47.3 mmol/l respectively. Consequently dry deposition effects on these materials have the potential to dominate over wet deposition effects. To test these predictions the geochemical models were applied to examples of data sets from mass balance (runoff vs rainfall) studies on a marble statue in New York City and some bronze memorial plaques at Gettysburg PA. Although these data sets were collected in the early 1980s they remain valid for demonstrating the mass balance method. For the marble statue, the mean Ca2+ losses by dry deposition was about 69% of the total compared 0.3% for acid rain neutralization, which was less than the natural carbonate dissolution losses of 0.8%. For the bronze, the mean Cu2+ losses were 70.6% by SO42- dry deposition and 23% by NO3- dry deposition compared to 6.4% by acid rain neutralization. Thus for both cases the wet

  12. Differential Gene Expression of Longan Under Simulated Acid Rain Stress.

    PubMed

    Zheng, Shan; Pan, Tengfei; Ma, Cuilan; Qiu, Dongliang

    2017-03-16

    Differential gene expression profile was studied in Dimocarpus longan Lour. in response to treatments of simulated acid rain with pH 2.5, 3.5, and a control (pH 5.6) using differential display reverse transcription polymerase chain reaction (DDRT-PCR). Results showed that mRNA differential display conditions were optimized to find an expressed sequence tag (EST) related with acid rain stress. The potential encoding products had 80% similarity with a transcription initiation factor IIF of Gossypium raimondii and 81% similarity with a protein product of Theobroma cacao. This fragment is the transcription factor activated by second messenger substances in longan leaves after signal perception of acid rain.

  13. Foliar nutrient status of Pinus ponderosa exposed to ozone and acid rain

    SciTech Connect

    Anderson, P.D.; Houpis, J.L.J. )

    1991-05-01

    A direct effect of foliar exposure to acid rain may be increased leaching of nutrient elements. Ozone exposure, through degradation of the cuticle and cellular membranes, may also result in increased nutrient leaching. To test these hypotheses, the foliar concentrations of 13 nutrient elements were monitored for mature branches of three clones of Pinus ponderosa exposed to ozone and/or acid rain. The three clones represented three distinct levels of phenotypic vigor. Branches were exposed to charcoal filtered, ambient, or 2 x ambient concentrations of ozone and received no acid rain (NAP), pH 5.1 rain (5.1), or pH 3.0 (3.0) rain. Following 10 months of continuous ozone exposure and 3 months of weekly rain applications, the concentrations of P and Mg differed significantly among rain treatments with a ranking of: 5.1 < NAP < 3.0. The S concentration increased with rain application regardless of pH. For the clones of moderate and low vigor, the concentration of N decreased with increasing rain acidity. There was no evidence of significant ozone or ozone x acid rain response. Among the three families, high phenotypic vigor was associated with significantly greater concentrations of N, P, K, Mg, B and An. These results indicate generally negligible leaching as a result of exposure to acid rain and/or ozone for one growing season. Increases in foliar concentrations of S, Mg and P are possibly the result of evaporative surface deposition from the rain solution.

  14. TECHNOLOGICAL OPTIONS FOR ACID RAIN CONTROL

    EPA Science Inventory

    Discussed are acid rain control options available to the electric utility industry. They include coal switching, flue gas desulfurization, and such emerging lower cost technologies as Limestone Injection Multistage Burners (LIMB) and Advanced Silicate (ADVACATE), both developed ...

  15. Effects of acid rain and sulfur dioxide on marble dissolution

    USGS Publications Warehouse

    Schuster, Paul F.; Reddy, Michael M.; Sherwood, Susan I.

    1994-01-01

    Acid precipitation and the dry deposition of sulfur dioxide (SO2) accelerate damage to carbonate-stone monuments and building materials. This study identified and quantified environmental damage to a sample of Vermont marble during storms and their preceding dry periods. Results from field experiments indicated the deposition of SO2 gas to the stone surface during dry periods and a twofold increase in marble dissolution during coincident episodes of low rain rate and decreased rainfall pH. The study is widely applicable to the analysis of carbonate-stone damage at locations affected by acid rain and air pollution.

  16. Effects of acid rain and sulfur dioxide on marble dissolution

    SciTech Connect

    Schuster, P.F.; Reddy, M.M. ); Sherwood, S.I. )

    1994-01-01

    Acid precipitation and the dry deposition of sulfur dioxide (SO[sub 2]) accelerate damage to carbonate-stone monuments and building materials. This study identified and quantified environmental damage to a sample of Vermont marble during storms and their preceding dry periods. Results from field experiments indicated the deposition of SO[sub 2] gas to the stone surface during dry periods and a twofold increase in marble dissolution during coincident episodes of low rain rate and decreased rainfall pH. The study is widely applicable to the analysis of carbonate-stone damage at locations affected by acid rain and air pollution.

  17. [Effects of simulated acid rain on Quercus glauca seedlings photosynthesis and chlorophyll fluorescence].

    PubMed

    Li, Jia; Jiang, Hong; Yu, Shu-quan; Jiang, Fu-wei; Yin, Xiu-min; Lu, Mei-juan

    2009-09-01

    Taking the seedlings of Quercus glauca, a dominant evergreen broadleaf tree species in subtropical area, as test materials, this paper studied their photosynthesis, chlorophyll fluorescence, and chlorophyll content under effects of simulated acid rain with pH 2.5, 4.0, and 5.6 (CK). After 2-year acid rain stress, the net photosynthetic rate of Q. glauca increased significantly with decreasing pH of acid rain. The acid rain with pH 2.5 and 4.0 increased the stomatal conductance and transpiration rate, and the effect was more significant under pH 2.5. The intercellular CO2 concentration decreased in the order of pH 2.5 > pH 5.6 > pH 4.0. The maximum photosynthetic rate, light compensation point, light saturation point, and dark respiration rate were significantly higher under pH 2.5 and 4.0 than under pH 5.6, while the apparent quantum yield was not sensitive to acid rain stress. The maximal photochemical efficiency of PS II and the potential activity of PS II under pH 2.5 and 4.0 were significantly higher than those under pH 5.6. The relative chlorophyll content was in the order of pH 2.5 > pH 5.6 > pH 4.0, and there was a significant difference between pH 2.5 and 4.0. All the results suggested that the photosynthesis and chlorophyll fluorescence of Q. glauca increased under the effects of acid rain with pH 2.5 and 4.0, and the acid rain with pH 2.5 had more obvious effects.

  18. The Effects of Acid Rain on Forest Nutrient Status

    NASA Astrophysics Data System (ADS)

    Johnson, Dale W.; Turner, John; Kelly, J. M.

    1982-06-01

    The effects of acidic atmospheric inputs on forest nutrient status must be assessed within the context of natural, internal acid production by carbonic and organic acids as well as the nutrient inputs and drains by management practices such as harvesting, fire, and fertilization. In all cases the anion associated with acid inputs must be mobile in the soil if leaching is to occur; immobilization of anions can effectively prevent cation leaching. Soil acidification will occur only if the often substantial buffering capacity of the soil in question is exceeded by acid inputs and if cation weathering from primary minerals is insufficient to offset cation losses by leaching. Such circumstances are rare but certainly could occur in theory, at least, given sufficiently large acid inputs on poorly buffered soils. Soils most sensitive to change are thought to be those of moderately acid pH and low cation exchange capacity. Neither very acid soils nor neutral, highly buffered soils are sensitive to acidification by acid rain. Given extremely high acid inputs, acid rain can cause temporary increases in nitrogen mineralization and nitritication as well as Al mobilization in soils. While temporary increases in N availability can cause increased forest growth in N-deficient forests, increased Al availability can cause toxic reactions in tree roots. Little is known about tree Al toxicity levels as yet, however. It must be emphasized that assessment of acid rain effects is a problem of quantification. Given sufficiently high inputs on sensitive sites, negative effects of acid rain must occur, as is true of inputs of any substance, including H2O. Acid rain inputs of sufficient magnitude to cause acute effects, such as growth increase due to N mobilization or growth decrease due to Al mobilization, are apparently very rare under ambient field conditions. Long-term effects on forest nutrient status can be either beneficial or adverse, depending on site nutrient status, silvicultural

  19. Acid rain and atmospheric chemistry at Allegheny Mountain

    SciTech Connect

    Pierson, W.R.; Brachaczek, W.W.; Gorse, R.A. Jr.; Japar, S.M.; Norbeck, J.M.; Keeler, G.J.

    1987-07-01

    Rain chemistry was measured in August 1983 on Allegheny Mountain and Larel Hill in southwester Pennsylvania. The average composition approximated an H/sub 2/SO/sub 5//HNO/sub 3/ mixture with a volume-weighted average pH of 3.5 and an SO/sub 4//sup 2 -//NO/sub 3//sup -/ mole ratio of 1.8. There was very little undissociated (weak) acidity and very little S(IV). The acidic rains were associated with air masses traversing SO/sub 2/ source regions west of the sites; stagnation and intervening precipitation were important influences. The geographic scale for a halving of rain SO/sub 4//sup 2 -/ concentration downwind of SO/sub 2/ sources was approx.440 km. Scavenging ratios were inferred for SO/sub 2/, aerosol SO/sub 4//sup 2 -/, and HNO/sub 3/. On average about half of the rain SO/sub 4//sup 2 -/ resulted from scavenging of SO/sub 2/, the rest from scavenging of SO/sub 4//sup 2 -/. The rain H/sup +/ was attributed about 25% to HNO/sub 3/, 55% to scavenging of SO/sub 2/, and 20% to scavenging of aerosol acid SO/sub 4//sup 2 -/. Cumulative deposition totals in rain were compared with deposition in fog and with dry deposition in the same experiment. A crude acid-deposition budget was calculated as follows: 47%, H/sub 2/SO/sub 4/ in rain; 23%, SO/sub 2/ dry deposition without dew; 16%, HNO/sub 3/ in rain; 11%, HNO/sub 3/ dry deposition without dew; 2%, HNO/sub 3/ and H/sub 2/SO/sub 4/ in fog and dew; 0.5%, aerosol dry deposition without dew. 86 references, 4 figures, 8 tables.

  20. [Characteristics and the impact factors of acid rain in Fuzhou and Xiamen 1992-2012].

    PubMed

    Zheng, Qiu-Ping; Wang, Hong; Chen, Bin-Bin; Sui, Ping; Lin, Wen

    2014-10-01

    Based on the observed acid rain data, synoptic situations and mass concentrations of atmospheric pollutants data from 1992 to 2012, the temporal variation characteristics and the impact factors of acid rain were analyzed in Fuzhou and Xiamen. The results showed that acid rain and non-acid rain accounted for 38.1% and 61.9% respectively in Fuzhou, 40.6% and 59.4% respectively in Xiamen. The annual average pH was 4.1-5.5 in Fuzhou. Acid rain pollution alleviated after 2007 in Fuzhou, and alleviated after 2006 in Xiamen. Acid rain was more serious in winter and spring than in summer and autumn. Precipitation intensity could affect the acidity of rain. Acid rain was observed more serious in southeast, southwest, west and northwest wind in Fuzhou, and more serious in northeast, southwest, west and northwest wind in Xiamen. Acid rain was most severe under the condition of transformed surface cold high, while most light under the conditions of typhoon (intertropical convergence zone) and outside of typhoon (intertropical convergence zone). There was a negative correlation between the mass concentrations of atmospheric pollutants, such as SO2, NO2, PM10, and the pH of rain in Fuzhou.

  1. Canada issues booklet describing acid rain

    NASA Astrophysics Data System (ADS)

    A booklet recently released by Environment Canada describes acid rain in terms easily understood by the general public. Although Acid Rain — The Facts tends somewhat to give the Canadian side of this intercountry controversial subject, it nevertheless presents some very interesting, simple statistics of interest to people in either the U.S. or Canada. Copies of the booklet can be obtained from Inquiry Environment Canada, Ottawa, Ontario K1A OH3, Canada, tel. 613-997-2800.The booklet points out that acid rain is caused by emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx). Once released into the atmosphere, these substances can be carried long distances by prevailing winds and return to Earth as acidic rain, snow, fog, or dust. The main sources of SO2 emissions in North America are coal-fired power generating stations and nonferrous ore smelters. The main sources of NOx emissions are vehicles and fuel combustion. From economical and environmental viewpoints, Canada believes acid rain is one of the most serious problems presently facing the country: increasing the acidity of more than 20% of Canada's 300,000 lakes to the point that aquatic life is depleted and acidity of soil water and shallow groundwater is increasing, causing decline in forest growth and water fowl populations, and eating away at buildings and monuments. Acid rain is endangering fisheries, tourism, agriculture, and forest resources in an area of 2.6 million km2 (one million square miles) of eastern Canada, about 8% of Canada's gross national product.

  2. Acid Rain Materials for Classroom Use.

    ERIC Educational Resources Information Center

    Factor, Lance; Kooser, Robert G.

    This booklet contains three separate papers suitable for use in an advanced high school or college chemistry course. The first paper provides background information on acids and bases. The second paper provides additional background information, focusing on certain aspects of atmospheric chemistry as it relates to the acid rain problem. An attempt…

  3. Acid Rain: A Student's First Sourcebook.

    ERIC Educational Resources Information Center

    Kyle, Beth Ann; And Others

    The purpose of this guide is to help students better understand the science, citizen action, and research issues that are part of the acid rain problem. The guide is designed for students in grades 4-8 and their teachers. Following an introduction, the first seven sections are informative in nature. They include: (1) "Observations about Acidity";…

  4. Study on the relationship between meteorological conditions and acid rain in mid-eastern Fujian.

    PubMed

    Lin, C C; Liu, J X; Cai, Y Y; Li, B L; Wang, Z L; Chen, B B

    2009-08-01

    Based on the acid rain observation data and the contemporaneous historical synoptic charts of Mid-Eastern Fujian during the period of 1991 to 2003, we analyzed the distribution characteristics of acid rain in different seasons, weather types, precipitation grades and wind directions. The results showed that the acid pollution in Mid-Eastern Fujian was still serious. In winter, the precipitation pH value was 4.79, and the acid rain frequency was 60.62% which was twice higher than that in summer. The pH value of warm shear-type precipitation at 850 hPa was 4.79. Nearly half of these precipitations had the problems of acid rain pollution. The acid rain frequency of the inverted trough type was only 26.11% which was the lowest one in all types. There was no marked difference of the acid rain distribution characteristics between ahead-of-trough and behind-the-trough. The precipitation pH values of the five grades were lower than 5.30 and the acid rain frequency changed as an inverted U shape with the increasing of the rainfall. The pH values of precipitations in the eight wind directions were generally below 5.20, and the acid rain frequencies were about 40%.

  5. Response of plasma membrane H+-ATPase in rice (Oryza sativa) seedlings to simulated acid rain.

    PubMed

    Liang, Chanjuan; Ge, Yuqing; Su, Lei; Bu, Jinjin

    2015-01-01

    Understanding the adaptation of plants to acid rain is important to find feasible approaches to alleviate such damage to plants. We studied effects of acid rain on plasma membrane H(+)-ATPase activity and transcription, intracellular H(+), membrane permeability, photosynthetic efficiency, and relative growth rate during stress and recovery periods. Simulated acid rain at pH 5.5 did not affect plasma membrane H(+)-ATPase activity, intracellular H(+), membrane permeability, photosynthetic efficiency, and relative growth rate. Plasma membrane H(+)-ATPase activity and transcription in leaves treated with acid rain at pH 3.5 was increased to maintain ion homeostasis by transporting excessive H(+) out of cells. Then intracellular H(+) was close to the control after a 5-day recovery, alleviating damage on membrane and sustaining photosynthetic efficiency and growth. Simulated acid rain at pH 2.5 inhibited plasma membrane H(+)-ATPase activity by decreasing the expression of H(+)-ATPase at transcription level, resulting in membrane damage and abnormal intracellular H(+), and reduction in photosynthetic efficiency and relative growth rate. After a 5-day recovery, all parameters in leaves treated with pH 2.5 acid rain show alleviated damage, implying that the increased plasma membrane H(+)-ATPase activity and its high expression were involved in repairing process in acid rain-stressed plants. Our study suggests that plasma membrane H(+)-ATPase can play a role in adaptation to acid rain for rice seedlings.

  6. [Analysis of acid rain characteristics of Lin'an Regional Background Station using long-term observation data].

    PubMed

    Li, Zheng-Quan; Ma, Hao; Mao, Yu-Ding; Feng, Tao

    2014-02-01

    Using long-term observation data of acid rain at Lin'an Regional Background Station (Lin'an RBS), this paper studied the interannual and monthly variations of acid rain, the reasons for the variations, and the relationships between acid rain and meteorological factors. The results showed that interannual variation of acid rain at Lin'an RBS had a general increasing trend in which there were two obvious intensifying processes and two distinct weakening processes, during the period ranging from 1985 to 2012. In last two decades, the monthly variation of acid rain at Lin'an RBS indicated that rain acidity and frequency of severe acid rain were increasing but the frequency of weak acid rain was decreasing when moving towards bilateral side months of July. Acid rain occurrence was affected by rainfall intensity, wind speed and wind direction. High frequency of severe acid rain and low frequency of weak acid rain were on days with drizzle, but high frequency of weak acid rain and low frequency of severe acid rain occurred on rainstorm days. With wind speed upgrading, the frequency of acid rain and the proportion of severe acid rain were declining, the pH value of precipitation was reducing too. Another character is that daily dominant wind direction of weak acid rain majorly converged in S-W section ,however that of severe acid rain was more likely distributed in N-E section. The monthly variation of acid rain at Lin'an RBS was mainly attributed to precipitation variation, the increasing and decreasing of monthly incoming wind from SSE-WSW and NWN-ENE sections of wind direction. The interannual variation of acid rain could be due to the effects of energy consumption raising and significant green policies conducted in Zhejiang, Jiangsu and Shanghai.

  7. Acid rain and electric utilities 2

    SciTech Connect

    1997-12-31

    This proceedings contains more than 100 technical presentations dealing with a variety of topics concerning the Title IV acid rain provisions of the Clean Air Act Amendments of 1990. Some of the major topics addressed include: emerging environmental issues impacting electric utilities (proposed revisions to the ozone and particulate matter NAAQS), acid rain program overview, continuous emissions monitoring rule revisions, global climate change and CO{sub 2}, emissions data management, Clean Air Power Initiative and regional issues, compliance/designated representative, flow monitoring, emissions control technology, allowance and trading, emission reductions, NO{sub x} control issues, hazardous air pollutants, and CEMS advances.

  8. Acid rain: Engineering solutions, regulatory aspects

    SciTech Connect

    Schwieger, R.G.; Elliott, T.C.

    1985-01-01

    Keeping up with efforts to control acid rain, this reference presents current scientific aspects associated with the problem of political and legislative concerns and ideas for developing effective mitigation programs at reasonable cost. The contributors are the authorities in attendance at the Second International Conference on Acid Rain - and this work represents the first time engineers and managers with firsthand knowledge of systems and equipment to reduce SO/sub 2/ and NO/sub x/ emissions gathered in one place. Throughout the book, some 200 tables, charts, diagrams, and photographs augment the textual material.

  9. Scientists Puzzle Over Acid Rain

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1975

    1975-01-01

    Reports on a growing concern over increased acidity in atmospheric percipitation. Explores possible causes of the increased acidity, identifies chemical components of precipitation in various parts of the world, and presents environmental changes that might be attributed to the acidity. (GS)

  10. Occurrence of acid rain in Baton Rouge, Louisiana, Summer 1981. The role of the catalytic converter

    SciTech Connect

    Robinson, J.W.; Ghane, H.

    1982-01-01

    Between June and October 1981, acid rain falling in Baton Rouge, LA was studied. The acidity of the rain ranged for pH 3.9 to pH 5.8. Preliminary data showed that rain associated with thermal cumulo nimbus tended to be more acidic, but rain associated with active cold fronts were less acid. This may relate to dispersion and dilution of the acid aerosols by the cold front. It is proposed that exhaust from automobiles fitted with catalytic converters is a substantial contributor to the acid rain problem, and that their net value to the abatement of pollution must be questioned, particularly in regions of the country where smog is not a problem. (JMT)

  11. [Effects of simulated acid rain on decomposition of soil organic carbon and crop straw].

    PubMed

    Zhu, Xue-Zhu; Huang, Yao; Yang, Xin-Zhong

    2009-02-01

    To evaluate the effects of acid rain on the organic carbon decomposition in different acidity soils, a 40-day incubation test was conducted with the paddy soils of pH 5.48, 6.70 and 8.18. The soils were amended with 0 and 15 g x kg(-1) of rice straw, adjusted to the moisture content of 400 g x kg(-1) air-dried soil by using simulated rain of pH 6.0, 4.5, and 3.0, and incubated at 20 degrees C. The results showed that straw, acid rain, and soil co-affected the CO2 emission from soil system. The amendment of straw increased the soil CO2 emission rate significantly. Acid rain had no significant effects on soil organic carbon decomposition, but significantly affected the straw decomposition in soil. When treated with pH 3.0 acid rain, the amount of decomposed straw over 40-day incubation in acid (pH 5.48) and alkaline (pH 8.18) soils was 8% higher, while that in neutral soil (pH 6.70) was 15% lower, compared to the treatment of pH 6.0 rain. In the treatment of pH 3.0 acid rain, the decomposition rate of soil organic C in acid (pH 5.48) soil was 43% and 50% (P < 0.05) higher than that in neutral (pH 6.70) and alkaline (pH 8.18) soils, while the decomposition rate of straw in neutral soil was 17% and 16% (P < 0.05) lower than that in acid and alkaline soils, respectively.

  12. Acid Rain Program CEM audit program

    SciTech Connect

    Nguyen, K.O.T.; Alexander, T.H.; Dupree, J.C.

    1997-12-31

    This presentation will give an overview of the Acid Rain Program CEM Audit Program: electronic and field audits. The presentation will include the reasons for audits, field audit types and levels the steps used in develop in the audit program and the audit procedures.

  13. Acid Rain: A Description of Bilingual Friesland.

    ERIC Educational Resources Information Center

    Zondag, Koen

    1984-01-01

    Using acid rain as a metaphor, discusses the status of the Frisian language and culture as one which, though apparently thriving, is really threatened. Examines the sources of this threat, i.e., the education system, the church, mass communication and transportation, and the demise of the Frisian village community. (SED)

  14. TECHNOLOGICAL OPTIONS FOR ACID RAIN CONTROL

    EPA Science Inventory

    The paper discusses technological options for acid rain control. Compliance with Title IV of the Clean Air Act Amendments of 1990 will require careful scrutiny of a number of issues before selecting control options to reduce sulfur dioxide (SO2) and nitrogen oxide (NOx) emissions...

  15. Acid Rain. Teacher's Guide. LHS GEMS.

    ERIC Educational Resources Information Center

    Hocking, Colin; Barber, Jacqueline; Coonrod, Jan

    This teacher's guide presents a unit on acid rain and introduces hands-on activities for sixth through eighth grade students. In each unit, students act as real scientists and gather evidence by using science process skills such as observing, measuring and recording data, classifying, role playing, problem solving, critical thinking, synthesizing…

  16. Acid Rain: Resource Materials for Schools.

    ERIC Educational Resources Information Center

    American Biology Teacher, 1983

    1983-01-01

    Provides listings of acid rain resource material groups under: (1) printed materials (pamphlets, books, articles); (2) audiovisuals (slide/tape presentations, tape, video-cassette); (3) miscellaneous (buttons, pocket lab, umbrella); (4) transparencies; (5) bibliographies; and (6) curriculum materials. Sources and prices (when applicable) are…

  17. Effects of acid rain on crops and trees

    SciTech Connect

    Cowling, E.B.; Dochinger, L.S.

    1984-01-01

    A general treatment of the subject of acid rain and its effets are discussed along with sources of acid rain and its near-term (the last couple of decades). The effects of acid rain on terrestrial ecosystems are treated in some detail. Some treatment is given of the ecosystem-level effects of acid precipitation.

  18. Fraud in the acid rain debate

    SciTech Connect

    Bagge, C.

    1984-06-01

    Electric utility executives, according to the author, and millions of other Americans are the victims of a gigantic fraud being carried on in the name of controlling acid rain. This fraud, states the author, involves the distorted, dire image of acidity in nature being created by environmental groups, politicians and others - to gain public sympathy for their legislative goals. The alleged fraud involves the very nature of the legislation being promoted as a low-cost cure for acid rain. On the basis of scientific evidence to date there is no assurance it will reduce acidity by any appreciable amount, but on the other hand it most certainly will cost users of electricity hundreds of billions of dollars in new costs. What has already happened to the nuclear industry is also meant for coal.

  19. A collaborative effort to model plant response to acidic rain

    SciTech Connect

    Jacobson, J.; Irving, P.; Kuja, A.; Lee, J.; Shriner, D.; Troiano, J.; Perrigan, S.; Cullinan, V.

    1989-01-01

    Radish plants were exposed three times per week to simulated acidic rain at pH values of 2.6 to 5.4 over the course of four weeks in trials performed at Argonne, Illinois; Ithaca and Upton, New York; Corvallis, Oregon; Oak Ridge, Tennessee; and Toronto, Canada. Uniform genotype, soil media and planting techniques, treatment procedures, biological measurements, and experimental design were employed. Growth of plants differed among trials as a result of variation in greenhouse environmental conditions according to location and facilities. Larger plants underwent greater absolute but lower relative reductions in biomass after exposure to the higher levels of acidity. A generalized Mitscherlich function was used to model the effects of acidity of simulated rain on dry mass of hypocotyls using data from three laboratories that performed duplicate trials. The remaining data, from three other laboratories that performed only one trial each, were used to test the model. 14 refs., 2 figs., 7 tabs.

  20. Acid Rain: A Global Perspective.

    ERIC Educational Resources Information Center

    Baldwin, John H.

    1985-01-01

    Analyzes the nature, extent, consequences, and sources of problems associated with acid precipitation. Explains the dilemma in specific countries with an emphasis on Eurasia, India, and the Artic. Discusses control options and international efforts to abate acidification in the environment. (ML)

  1. Acid rain on acid soil: a new perspective

    SciTech Connect

    Krug, E.C.; Frink, C.R.

    1983-08-05

    Acid rain is widely believed to be responsible for acidifying soil and water in areas of North America and Northern Europe. However, factors commonly considered to make landscapes susceptible to acidification by acid rain are the same factors long known to strongly acidify soils through the natural processes of soil formation. Recovery from extreme and widespread careless land use has also occurred in regions undergoing acidification. There is evidence that acidification by acid rain is superimposed on long-term acidification induced by changes in land use and consequent vegetative succession. Thus, the interactions of acid rain, acid soil, and vegetation need to be carefully examined on a watershed basis in assessing benefits expected from proposed reductions in emissions of oxides of sulfur and nitrogen.

  2. Acid rain on acid soil: a new perspective

    SciTech Connect

    Krug, E.C.; Frink, C.R.

    1983-08-05

    Acid rain is widely believed to be responsible for acidifying soil and water in areas of North America and northern Europe. However, factors commonly considered to make landscapes susceptible to acidification by acid rain are the same factors long known to strongly acidify soils through the natural processes of soil formation. Recovery from extreme and widespread careless land use has also occurred in regions undergoing acidification. There is evidence that acidification by acid rain is superimposed on long-term acidification induced by changes in land use and consequent vegetative succession. Thus, the interactions of acid rain, acid soil, and vegetation need to be carefully examined on a watershed basis in assessing benefits expected from proposed reductions in emissions of oxides of sulfur and nitrogen.

  3. Acid-rain induced changes in streamwater quality during storms on Catoctin Mountain, Maryland

    USGS Publications Warehouse

    Rice, Karen C.; Bricker, O.P.

    1992-01-01

    Catoctin Mountain receives some of the most acidic (lowest pH) rain in the United States. In 1990, the U.S. Geological Survey (USGS), in cooperation with the Maryland Department of the Environment (MDE) and the Maryland Department of Natural Resources (DNR), began a study of the effects of acid rain on the quality of streamwater on the part of Catoctin Mountain within Cunningham Falls State Park, Maryland (fig. 1). Samples of precipitation collected on the mountain by the USGS since 1982 have been analyzed for acidity and concentration of chemical constituents. During 1982-91, the volume-weighted average pH of precipitation was 4.2. (Volume weighting corrects for the effect of acids being washed out of the atmosphere at the beginning of rainfall). The pH value is measured on a logarithmic scale, which means that for each whole number change, the acidity changes by a factor of 10. Thus rain with a pH of 4.2 is more than 10 times as acidic as uncontaminated rain, which has a pH of about 5.6. The acidity of rain during several rainstorms on Catoctin Mountain was more than 100 times more acidic than uncontaminated rain.

  4. Effects of simulated acid rain on soil fauna community composition and their ecological niches.

    PubMed

    Wei, Hui; Liu, Wen; Zhang, Jiaen; Qin, Zhong

    2017-01-01

    Acid rain is one of the severest environmental issues globally. Relative to other global changes (e.g., warming, elevated atmospheric [CO2], and nitrogen deposition), however, acid rain has received less attention than its due. Soil fauna play important roles in multiple ecological processes, but how soil fauna community responds to acid rain remains less studied. This microcosm experiment was conducted using latosol with simulated acid rain (SAR) manipulations to observe potential changes in soil fauna community under acid rain stress. Four pH levels, i.e., pH 2.5, 3.5, 4.5, and 5.5, and a neutral control of pH 7.0 were set according to the current pH condition and acidification trend of precipitation in southern China. As expected, we observed that the SAR treatments induced changes in soil fauna community composition and their ecological niches in the tested soil; the treatment effects tended to increase as acidity increased. This could be attributable to the environmental stresses (such as acidity, porosity and oxygen supply) induced by the SAR treatments. In addition to direct acidity effect, we propose that potential changes in permeability and movability of water and oxygen in soils induced by acid rain could also give rise to the observed shifts in soil fauna community composition. These are most likely indirect pathways of acid rain to affect belowground community. Moreover, we found that nematodes, the dominating soil fauna group in this study, moved downwards to mitigate the stress of acid rain. This is probably detrimental to soil fauna in the long term, due to the relatively severer soil conditions in the deep than surface soil layer. Our results suggest that acid rain could change soil fauna community and the vertical distribution of soil fauna groups, consequently changing the underground ecosystem functions such as organic matter decomposition and greenhouse gas emissions.

  5. 40 CFR 76.3 - General Acid Rain Program provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 16 2011-07-01 2011-07-01 false General Acid Rain Program provisions. 76.3 Section 76.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.3 General Acid Rain Program...

  6. 40 CFR 76.3 - General Acid Rain Program provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false General Acid Rain Program provisions. 76.3 Section 76.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.3 General Acid Rain Program...

  7. 40 CFR 76.3 - General Acid Rain Program provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 17 2013-07-01 2013-07-01 false General Acid Rain Program provisions. 76.3 Section 76.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.3 General Acid Rain Program...

  8. 40 CFR 76.3 - General Acid Rain Program provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 17 2014-07-01 2014-07-01 false General Acid Rain Program provisions. 76.3 Section 76.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.3 General Acid Rain Program...

  9. 40 CFR 76.3 - General Acid Rain Program provisions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 17 2012-07-01 2012-07-01 false General Acid Rain Program provisions. 76.3 Section 76.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.3 General Acid Rain Program...

  10. Acid rain in Shenandoah National Park, Virginia

    USGS Publications Warehouse

    Rice, Karen C.; Deviney, Frank A.; Olson, Gordon

    2007-01-01

    Visitors to Shenandoah National Park (SNP) enjoy the animal and plant life and the scenery but may not realize how vulnerable these features are to various threats, such as invasion of exotic plants and insects, improper use of park resources by humans, and air and water pollution. The National Park Service strives to protect natural resources from such threats to ensure that the resources will be available for enjoyment now and in the future. Because SNP has limited influence over the air pollution that envelops the region, acidic deposition--commonly known as acid rain--is one of the more challenging threats facing park managers. With the help of U.S. Geological Survey (USGS) scientists, park managers can understand how acid rain interacts with ground- and surface-water resources, which enables them to explain why reductions in air pollution can help preserve park resources. Such understanding also provides essential insight into ecosystem processes, as managers strive to unravel and resolve other environmental problems that are interrelated to acid rain.

  11. The Acid Rain Program: Monitoring the future

    SciTech Connect

    Bloomer, B.J.

    1995-12-31

    This paper presents a summary of the development of the Acid Rain Program`s approach to Continuous Emissions Monitoring Systems (CEMS) and their use in the market based pollution control program of Title IV of the Clean Air Act Amendments of 1990. The roles of the regulatory agencies are discussed and projections are put forward as to how the roles will evolve over time. In addition a discussion of the activities the regulated community is expected to focus on is presented. Finally, a discussion occurs about the requirements that new technologies and instrument providers and purchasers should keep in mind about the Acid Rain Program`s monitoring requirements as they attempt to bring new products into this market.

  12. Combined effects of lanthanum (III) chloride and acid rain on photosynthetic parameters in rice.

    PubMed

    Wang, Lihong; Wang, Wen; Zhou, Qing; Huang, Xiaohua

    2014-10-01

    Rare earth elements (REEs) pollution and acid rain are environmental issues, and their deleterious effects on plants attract worldwide attention. These two issues exist simultaneously in many regions, especially in some rice-growing areas. However, little is known about the combined effects of REEs and acid rain on plants. Here, the combined effects of lanthanum chloride (LaCl3), one type of REE salt, and acid rain on photosynthesis in rice were investigated. We showed that the combined treatment of 81.6 μM LaCl3 and acid rain at pH 4.5 increased net photosynthetic rate (Pn), stomatic conductance (Gs), intercellular CO2 concentration (Ci), Hill reaction activity (HRA), apparent quantum yield (AQY) and carboxylation efficiency (CE) in rice. The combined treatment of 81.6 μM LaCl3 and acid rain at pH 3.5 began to behave toxic effects on photosynthesis (decreasing Pn, Gs, HRA, AQY and CE, and increasing Ci), and the maximally toxic effects were observed in the combined treatment of 2449.0 μM LaCl3 and acid rain at pH 2.5. Moreover, the combined effects of LaCl3 and acid rain on photosynthesis in rice depended on the growth stage of rice, with the maximal effects occurring at the booting stage. Furthermore, the combined treatment of high-concentration LaCl3 and low-pH acid rain had more serious effects on photosynthesis in rice than LaCl3 or acid rain treatment alone. Finally, the combined effect of LaCl3 and acid rain on Pn in rice resulted from the changes in stomatic (Gs, Ci) and non-stomatic (HRA, AQY and CE) factors.

  13. [Effects of acid rain stress on Eleocarpus glabripetalus seedlings leaf chlorophyll fluorescence characteristics and growth].

    PubMed

    Yin, Xiu-Min; Yu, Shu-Quan; Jiang, Hong; Liu, Mei-Hu

    2010-06-01

    A pot experiment was conducted to study the Eleocarpus glabripetalus seedlings leaf chlorophyll fluorescence characteristics and growth in different seasons under simulated acid rain stress (heavy, pH = 2. 5; moderate, pH = 4.0; and control, pH = 5.6). In the same treatments, the leaf relative chlorophyll content (SPAD), maximum PS II photochemical efficiency (F(v)/F(m)), actual PSII photochemical quantum yield (phi(PS II)), plant height, and stem diameter in different seasons were all in the order of October > July > April > January. In the same seasons, all the parameters were in the order of heavy acid rain > moderate acid rain > control. The interactions between different acid rain stress and seasons showed significant effects on the SPAD, F(v)/F(m), plant height, and stem diameter, but lesser effects on phi(PS II), qp and qN.

  14. State acid rain permitting programs: A report from EPA

    SciTech Connect

    Miller, R.L.

    1995-12-31

    States and EPA are laying the groundwork for state acid rain permitting in Phase 2 of the Acid Rain Program. Early indications suggest a high degree of state compliance with the acid rain permitting requirements of the Acid Rain Program. Phase 2 acid rain permitting forms have been revised and are available on EPA`s Technology Transfer Network. EPA has developed a policy and rationale concerning submission of Phase 2 permit applications, as well as suggested state timing and methodology regarding adoption of 40 CFR Part 76, the NO{sub x} regulation.

  15. [Release of Si, Al and Fe in red soil under simulated acid rain].

    PubMed

    Liu, Li; Song, Cun-yi; Li, Fa-sheng

    2007-10-01

    bstract:A laboratory leaching experiment on simulated acid rain was carried out using soil columns. The release of Si, Al and Fe from soils and pH values of eluates were investigated. The results showed that under the given leaching volume, the release amounts of cations were influenced by the pH value of simulated acid rain, while their response to acid rain was different. Acid rain led to Si release, nearly none of Fe. Within the range from pH 3.0 to 5.6, a little Al release but mass Al only release at the pH below 3.0, both Si and Al had a declining release ability with the undergoing eluviation. At pH 2.5, the release amounts of Si and Al, especially Al, increased significantly with the strengthened weathering process of soil mineral. With an increase of the leaching amount of acid rain, the release of Si and Al increased, but acceleration of Si was slower than Al which was slower and slower. When the soil pH falling down to a certain grade, there are negative correlation between pH and both Al and DOC concentration of eluate. released, but most of Al derived from the aluminosilicates dissolved. Acid deposition can result in solid-phase alumino-organics broken and Al released, but most of Al derived from the aluminosilicates dissolved.

  16. NAPAP (National Acid Precipitation Assessment Program) results on acid rain

    SciTech Connect

    Not Available

    1990-06-01

    The National Acid Precipitation Assessment Program (NAPAP) was mandated by Congress in 1980 to study the effects of acid rain. The results of 10 years of research on the effect of acid deposition and ozone on forests, particularly high elevation spruce and fir, southern pines, eastern hardwoods and western conifers, will be published this year.

  17. Effects of pretreatment with simulated acid rain on the severity of dogwood anthracnose

    SciTech Connect

    Britton, K.O.; Berrang, P.; Mavity, E.

    1996-06-01

    The effects of simulated acid rain on dogwood anthracnose severity were evaluated in a series of greenhouse and field experiments over a 4-year period. In 1990 and 1991, Cornus florida seedlings received 10 weekly foliar applications of simulated rain adjusted to pH 2.5, 3.5, 4.5, and 5.5. They were then placed under mature dogwoods naturally infected with Discula destructive. In both years, the percent leaf area infected increased significantly as the pH of the simulated rain solution decreased. In 1992 and 1993, seedlings were wrapped in plastic bags below the root collar to permit separate application of simulated acid rain (pH 2.5) or normal rain (pH 5.5) to the foliage or the growing medium or both. Application of pH 2.5 rain to the growing medium increased disease severity. Foliar applications alone did not increase disease. These results suggest that changes in nutrient availability, rather than foliar damage, are responsible for the increase in anthracnose severity in dogwoods pretreated with simulated acid rain. 41 refs., 1 fig., 1 tab.

  18. Effects and mechanism of acid rain on plant chloroplast ATP synthase.

    PubMed

    Sun, Jingwen; Hu, Huiqing; Li, Yueli; Wang, Lihong; Zhou, Qing; Huang, Xiaohua

    2016-09-01

    Acid rain can directly or indirectly affect plant physiological functions, especially photosynthesis. The enzyme ATP synthase is the key in photosynthetic energy conversion, and thus, it affects plant photosynthesis. To clarify the mechanism by which acid rain affects photosynthesis, we studied the effects of acid rain on plant growth, photosynthesis, chloroplast ATP synthase activity and gene expression, chloroplast ultrastructure, intracellular H(+) level, and water content of rice seedlings. Acid rain at pH 4.5 remained the chloroplast structure unchanged but increased the expression of six chloroplast ATP synthase subunits, promoted chloroplast ATP synthase activity, and increased photosynthesis and plant growth. Acid rain at pH 4.0 or less decreased leaf water content, destroyed chloroplast structure, inhibited the expression of six chloroplast ATP synthase subunits, decreased chloroplast ATP synthase activity, and reduced photosynthesis and plant growth. In conclusion, acid rain affected the chloroplast ultrastructure, chloroplast ATPase transcription and activity, and P n by changing the acidity in the cells, and thus influencing the plant growth and development. Finally, the effects of simulated acid rain on the test indices were found to be dose-dependent.

  19. A numerical study of the acid rain in northern Taiwan in winter season

    SciTech Connect

    Chen, Ching-Sen; Deng, Zen-Sing

    1996-12-31

    Two-thirds of the land mass of Taiwan island is covered by mountains. In winter precipitation could occur in northern Taiwan when the prevailing wind was from northeastern direction. In northern Taiwan the acid rain (pH value less than 5.0) in winter time could contribute about 30 rain in the whole year. A three-dimensional numerical model with terrain following coordinated system was used to simulate the precipitation system and the characteristics of acid rain. A smooth terrain was assumed in the model. A mean sounding was used to initialize the numerical model when acid rain occurred in northern Taiwan during winter time from 1991 to 1993. Investigations of the effect of pollutions from abroad on the acid rain in northern Taiwan in winter are considered for the future.

  20. Prolonged acid rain facilitates soil organic carbon accumulation in a mature forest in Southern China.

    PubMed

    Wu, Jianping; Liang, Guohua; Hui, Dafeng; Deng, Qi; Xiong, Xin; Qiu, Qingyan; Liu, Juxiu; Chu, Guowei; Zhou, Guoyi; Zhang, Deqiang

    2016-02-15

    With the continuing increase in anthropogenic activities, acid rain remains a serious environmental threat, especially in the fast developing areas such as southern China. To detect how prolonged deposition of acid rain would influence soil organic carbon accumulation in mature subtropical forests, we conducted a field experiment with simulated acid rain (SAR) treatments in a monsoon evergreen broadleaf forest at Dinghushan National Nature Reserve in southern China. Four levels of SAR treatments were set by irrigating plants with water of different pH values: CK (the control, local lake water, pH ≈ 4.5), T1 (water pH=4.0), T2 (water pH=3.5), and T3 (water pH=3.0). Results showed reduced pH measurements in the topsoil exposed to simulated acid rains due to soil acidification. Soil respiration, soil microbial biomass and litter decomposition rates were significantly decreased by the SAR treatments. As a result, T3 treatment significantly increased the total organic carbon by 24.5% in the topsoil compared to the control. Furthermore, surface soil became more stable as more recalcitrant organic matter was generated under the SAR treatments. Our results suggest that prolonged acid rain exposure may have the potential to facilitate soil organic carbon accumulation in the subtropical forest in southern China.

  1. Technological options for acid rain control

    SciTech Connect

    Princiotta, F.T.; Sedman, C.B.

    1993-01-01

    The paper discusses technological options for acid rain control. Compliance with Title IV of the Clean Air Act Amendments of 1990 will require careful scrutiny of a number of issues before selecting control options to reduce sulfur dioxide (SO2) and nitrogen oxide (NOx) emissions. One key consideration is the effect of fuel switching or control technology upon the existing dust collector, with additional air toxics legislation looming ahead. A number of likely SO2 and NOx retrofit technologies and estimated costs are presented, along with results of retrofit case studies. New hybrid particulate controls are also being developed to meet future requirements.

  2. Acid rain reduced in eastern United States

    SciTech Connect

    Bowersox, V.C.; Lynch, J.A.; Grimm, J.W.

    1997-12-31

    Sulfate and free hydrogen ion concentrations in precipitation decreased 10 to 25 percent over large areas of the eastern United States in 1995. The largest decreases in both ions occurred in and downwind of the Ohio River Valley, the same area where Phase I of the 1990 Clean Air Act Amendments set limitations, effective January 1, 1995, on sulfur dioxide emissions from affected coal-fired sources. Based on our analysis of precipitation chemistry and emissions data, we conclude that substantial declines in acid rain occurred in the eastern United States in 1995 because of large reductions in sulfur dioxide emissions in the same region.

  3. The greenhouse effect and acid rain

    SciTech Connect

    Traeger, R.K.

    1990-01-01

    The concentrations of carbon dioxide, methane, sulfur dioxide, nitrous oxides and chlorofluorocarbons is increasing in the earth's atmosphere. Increased concentrations of these trace gases could lead to global warming, increased acid rain and increased UV radiation on the earth's surface; however, the actual impacts are still uncertain and are also the subject of great debate. Application of clean'' energy sources such as geothermal are obviously desirable for decreasing these effects and improving our overall general environment. This paper briefly summarizes the global environment concerns, providing a backdrop for the following papers which describe the geothermal role in future environmental considerations. 5 refs., 2 figs., 1 tab.

  4. [Effects of simulated acid rain on leaf photosynthate, growth, and yield of wheat].

    PubMed

    Mai, Bo-Rui; Zheng, You-Fei; Liang, Jun; Liu, Xia; Li, Lu; Zhong, Yan-Chuan

    2008-10-01

    With winter wheat variety Yamgmai 12 as test object, a field experiment was conducted to study the stress of simulated acid rain on its growth and development. The results showed that simulated acid rain had considerable effect on wheat growth and yield. When the pH of acid rain was < or = 3.5, the growth of leaf area as well as the mass of fresh leaf per unit area declined greatly, and the yield was significantly lower than CK. When pH was < or = 2.5, the plant height was obviously lowered, and the visible injury on leaf surface was observed. Under acid rain stress, the contents of leaf chlorophyll a, chlorophyll b, and carotenoid, especially chlorophyll a, decreased obviously. Acid rain also suppressed the synthesis of soluble sugar and reduced sugar, and the suppression was stronger at pH < or = 3.5, and became much stronger with increasing acidity. The total free amino acid and soluble protein contents in leaves decreased with increasing acidity, and were significantly lower than CK when the pH was < or = 3.5 and < or = 4.5, respectively.

  5. Growth and xylem water potential of white oak and loblolly pine seedlings as affected by simulated acidic rain

    SciTech Connect

    Walker, R.F. ); McLaughlin, S.B. )

    1993-01-01

    Effects of simulated acidic rainfall on the growth and water relations of white oak (Quercus albya L.) and loblolly pin (Pinus taeda L.) seedlings grown under two fertility regimes were examined. Seedling of each species grown in a loam soil were exposed to two simulated rains per week of pH 4.8, 4.2 or 3.6 for 26 wk. High and low fertility regimes were imposed by monthly application of one-half and one-quarter concentration, respectively, of Hoagland's solution No. 2. Diameter growth of both species was reduced by exposure to rains of the higher acidities regardless of fertility treatment, and seedlings that received pH 4.2 and 3.6 rains also exhibited greater foliar chlorosis and necrosis than those that received rains of pH 4.8. The high fertility treatment stimulated diameter growth of white oak, but height growth, shoot and root dry weights and total root length were no substantially affected b acid rain or fertility treatments in either species. Following the final rain applications, drought was simulated by withholding irrigation for 2 wk, and seedling xylem pressure potential was then measured using the pressure chamber technique. Xylem pressure potential of white oak seedlings which had received rains of pH 3.6 was significantly lower than that of seedlings which had received rains of higher pH, a result that became more pronounced as soil water potential decreased. Rain acidity had little effect on the xylem pressure potential of loblolly pine, however. Soil pH analyses before initiation and after completion of the rain applications indicated that rainfall of pH 3.6 increased soil acidity more than rains of pH 4.2 or 4.8, although changes in soil pH were small overall. 26 refs., 1 fig. 2 tabs.

  6. California's fog is far more polluted than acid rain

    SciTech Connect

    Roberts, L.

    1982-11-01

    In the Los Angeles area, measurements reveal that the fog has a pH between 2.5 and 3. Near congested areas, the fog is consistenly acidic and is laden with sulfate, nitrate, ammonium ion, lead, copper, nickel, vanadium and aldehydes. Acid fog formation involves a conversion of SO/sub 2/ and NO/sub x/ to sulfuric and nitric acids. Unlike acid rain, acid fog remains suspended in the air for hours and is a threat to human health as well as vegetation and materials. Fog forms close to the ground where concentrations of pollutants are higher than they are further aloft. Acid fog seems to be related to ground-based pollution sources, particularly power plant and automobile emissions. Samples were collected in locations far from major pollution sources and used to test the composition and acidity of normal fog. The pH values ranged from 3, near Los Angeles, to 7, near Morro Bay. Mathematical models are used to explain changes in acidity over time and to indicate a cyclical pattern.

  7. [Spatiotemporal trends and the impact factors of acid rain in Anhui Province].

    PubMed

    Shi, Chun-E; Qiu, Ming-Yan; Zhang, Ai-Min; Zhang, Hao; Zhang, Su; Wang, Zi-Fa

    2010-06-01

    The observational data of acid rain at seven stations in Anhui province operated by China Meteorological Administration (CMA), as well as the coal consumptions in Anhui and some surrounding provinces along with satellite measured tropospheric NO2 columns, were used to analyze the spatiotemporal trends of acid rain in Anhui and the potential reasons of the increasing occurrence frequency of acid rain. In addition, the technique of back-trajectory-cluster analysis was used to examine the impacts of transport patterns on the precipitation acidity in Anhui. The occurrence frequency shows the lowest in summer and the highest in autumn, with 3-year average pH < 5.6 during 2006-2008 at all stations, hereinto, pH values are between 5.0 and 4.5 in Hefei, Anqing, Maanshan and Bengbu. In spatial, acid rain were the most severe in southern to middle Anhui and mitigated to north. The distributions of pH were concentrative at Fuyang, Tongling and Huangshan, with more than 75% occurred between 6.00-7.50 (Fuyang), 5.00-6.00 (Tongling) and 5.00-6.50 (Huangshan); quite dispersive at other stations, with the maximum at 4.00-4.50 (Hefei and Anqing), 5.00-5.50 (Maanshan) and 5.50-6.00 (Bengbu). The occurrence frequencies of acid rain increased evidently at all stations comparing with those in the end of 1990s. The results of back-trajectories-cluster analysis show that the acid rain is closely related with the regional-range transport of acid rain precursors at each station. The air-masses from southeast and northeast, especially those passing through Jiangsu and Zhejiang, associated with the highest frequencies of acid rain with pH < 5.0, indicating that the industrial emissions in the economy developed areas of Yangtze Delta play key roles in acid rain in Anhui province. In addition, statistics shows that the occurrence frequency of acid rain in Hefei was highly correlated with the trends of the provincial coal consumptions in Anhui, Jiangsu and Zhejiang, also tropospheric NO2 column

  8. Trace element composition characteristics and acidity of central-Alabama rain

    NASA Astrophysics Data System (ADS)

    Ghorai, S. K.; Tekyi-Mensah, O.; Sims, J. F.; Williams, J. R.; Alford, W. L.

    1991-11-01

    Elemental concentrations and acidity of central Alabama rain have been studied by the proton induced X-ray emission (PIXE) method. Seventeen elements (Na, Si, P, S, Cl, Ar, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn) have been found to occur in the rain samples. Samples collected during the initial five-month period (January-May, 1985) showed characteristics that are described here. The elemental composition of southerly air flow rains was found to be different from that of northerly air flow rains with the latter containing relatively higher concentrations of S, Ca, Cu and Zn, indicating a more polluted area to the north. Correlation coefficients were calculated for pairs of elements in an attempt to determine possible sources of pollutants. A strong correlation was found between pH and logarithmic sulfur concentration for northern rains but not for southern rains.

  9. A field test of the effect of acidic rain on ion balance in a woodland salamander

    SciTech Connect

    Frisbie, M.P.; Wyman, R.L. )

    1994-06-01

    Earlier laboratory studies demonstrated that red-backed salamanders, Plethodon cinereus, are susceptible to osmotic disruption by low pH substrates. In natural systems, however, acidic input from precipitation may be mediated by soils before it impacts salamanders. We tested the effect of acidic rain on sodium balance in salamanders by confining individuals in enclosure in two forest types (hemlock, beech) for 34 d. Enclosures received artificial rain of either pH 3 or 5 every 3-4 d. Soils inside enclosures in the hemlock forest were more acidic than those in the beech forest at the outset. At termination, [H[sup +

  10. Selenium speciation in acidic environmental samples: application to acid rain-soil interaction at Mount Etna volcano.

    PubMed

    Floor, Geerke H; Iglesías, Mònica; Román-Ross, Gabriela; Corvini, Philippe F X; Lenz, Markus

    2011-09-01

    Speciation plays a crucial role in elemental mobility. However, trace level selenium (Se) speciation analyses in aqueous samples from acidic environments are hampered due to adsorption of the analytes (i.e. selenate, selenite) on precipitates. Such solid phases can form during pH adaptation up till now necessary for chromatographic separation. Thermodynamic calculations in this study predicted that a pH<4 is needed to prevent precipitation of Al and Fe phases. Therefore, a speciation method with a low pH eluent that matches the natural sample pH of acid rain-soil interaction samples from Etna volcano was developed. With a mobile phase containing 20mM ammonium citrate at pH 3, selenate and selenite could be separated in different acidic media (spiked water, rain, soil leachates) in <10 min with a LOQ of 0.2 μg L(-1) using (78)Se for detection. Applying this speciation analysis to study acid rain-soil interaction using synthetic rain based on H(2)SO(4) and soil samples collected at the flanks of Etna volcano demonstrated the dominance of selenate over selenite in leachates from samples collected close to the volcanic craters. This suggests that competitive behavior with sulfate present in acid rain might be a key factor in Se mobilization. The developed speciation method can significantly contribute to understand Se cycling in acidic, Al/Fe rich environments.

  11. Effects of simulated sulfuric acid rain on yield, growth, and foliar injury of several crops

    SciTech Connect

    Lee, J.J.; Neely, G.E.; Perrigan, S.C.; Grothaus, L.C.

    1980-10-01

    This study was designed to reveal patterns of response of major United States crops to sulfuric acid rain. Potted plants were grown in field chambers and exposed to simulated sulfuric acid rain (pH 3.0, 3.5 or 4.0) or to a control rain (pH 5.6). At harvest, the weights of the marketable portion, total aboveground portion and roots were determined for 28 crops. Of these, marketable yield production was inhibited for 5 crops (radish, beet, carrot, mustard greens, broccoli), stimulated for 6 crops (tomato, green pepper, strawberry, alfalfa, orchardgrass, timothy), and ambiguously affected for 1 crop (potato). In addition, stem and leaf production of sweet corn was stimulated. Visible injury of tomatoes might have decreased their marketability. No statistically significant effects on yield were observed for the other 15 crops. The results suggest that the likelihood of yield being affected by acid rain depends on the part of the plant utilized, as well as on species. Effects on the aboveground portions of crops and on roots are also presented. Plants were regularly examined for foliar injury associated with acid rain. Of the 35 cultivars examined, the foliage of 31 was injured at pH 3.0, 28 at pH 3.5, and 5 at pH 4.0. Foliar injury was not generally related to effects on yield. However, foilar injury of swiss chard, mustard greens and spinach was severe enough to adversely affect marketability.

  12. Collaborative effort to model plant response to acidic rain

    SciTech Connect

    Jacobson, J.; Kuja, A.; Shriner, D.; Perrigan, S.; Irving, P.; Lee, J.; Troiano, J.; Cullinan, V.

    1988-06-01

    Radish plants were exposed three times per week to simulated acidic rain at pH values of 2.6 to 5.4 over the course of four weeks in trials performed at Argonne, Illinois; Ithaca and Upton, New York; Corvallis, Oregon; Oak Ridge, Tennessee; and Toronto, Canada. Uniform genotype, soil media and planting techniques, treatment procedures, biological measurements, and experimental design were employed. Growth of plants differed among trials as a result of variation in greenhouse environmental conditions according to location and facilities. Larger plants underwent greater absolute but lower relative reductions in biomass after exposure to the higher levels of acidity. A generalized Mitscherlich function was used to model the effects of acidity of simulated rain or dry mass of hypocotyls using data from three laboratories that performed duplicate trials. The remaining data, from three other laboratories that performed only one trial each, were used to test the model. When the laboratory by trial effect was removed, lack of fit to the Mitscherlich function was insignificant. Thus, a single mathematical model satisfactorily characterized the relationship between acidity and mean plant response.

  13. Acid rain at Kennedy Space Center, Florida - Recent observations

    NASA Technical Reports Server (NTRS)

    Madsen, B. C.

    1981-01-01

    During the period July, 1977 to September, 1979, rainfall was collected in the vicinity of the Kennedy Space Center and subjected to appropriate chemical analysis for purposes of characterization of general composition and acidity. Results obtained form the basis for future comparisons, should significant alteration of the chemical composition of rain occur during the space shuttle era. Acidity extremes calculated on a monthly basis from event samples collected from five sites within a 200 sq km area varied from pH 5.1 in November, 1977, and April, 1978 to pH 4.3 in July, 1978 and July, 1979. Weighted average pH for the entire period was 4.55. Acidity was due to the presence of sulfuric and nitric acids. The mole ratio of excess SO4(-2):NO3(-) was typically greater than one. Monthly weighted average Cl(-) concentrations ranged from 20-240 micromoles/liter. The Cl(-):Na(+) ratio was slightly lower than that present in sea water.

  14. 40 CFR 75.3 - General Acid Rain Program provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 17 2014-07-01 2014-07-01 false General Acid Rain Program provisions. 75.3 Section 75.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTINUOUS EMISSION MONITORING General § 75.3 General Acid Rain Program provisions....

  15. 40 CFR 75.3 - General Acid Rain Program provisions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 17 2012-07-01 2012-07-01 false General Acid Rain Program provisions. 75.3 Section 75.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTINUOUS EMISSION MONITORING General § 75.3 General Acid Rain Program provisions....

  16. 40 CFR 75.3 - General Acid Rain Program provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 16 2011-07-01 2011-07-01 false General Acid Rain Program provisions. 75.3 Section 75.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTINUOUS EMISSION MONITORING General § 75.3 General Acid Rain Program provisions....

  17. 40 CFR 75.3 - General Acid Rain Program provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false General Acid Rain Program provisions. 75.3 Section 75.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTINUOUS EMISSION MONITORING General § 75.3 General Acid Rain Program provisions....

  18. 40 CFR 75.3 - General Acid Rain Program provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 17 2013-07-01 2013-07-01 false General Acid Rain Program provisions. 75.3 Section 75.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTINUOUS EMISSION MONITORING General § 75.3 General Acid Rain Program provisions....

  19. Elementary Acid Rain Kit, Interdisciplinary, Grades 4-8.

    ERIC Educational Resources Information Center

    Stubbs, Harriett S.; And Others

    An interdisciplinary approach for teaching about acid rain is offered in this curriculum guide for teachers of grades 4-8. Skill and concept areas of science, math, social studies, art, and the language arts are developed in 12 activities which focus on the acid rain problems. A matrix of the activities and subject areas indicates the coverage…

  20. Acid rain compliance: The need for regulatory guidance

    SciTech Connect

    Solomon, B.D.

    1993-07-01

    This article presents a broad view of the need for regulatory guidance when confronting the problem of acid rain. The two major topics addressed are (1) Why is guidance needed and (2) What kind of guidance is needed. Discussion of rate and accounting treatment of allowances, acid rain compliance planning, and allowance trading and energy efficiency are included.

  1. Interactions between greenhouse gas policies and acid rain control strategies

    SciTech Connect

    Klein, D.E.; Kane, R.L.; Mansueti, L.

    1997-12-31

    Conventional wisdom and much of the public policy debate have usually drawn a clean delineation between acid rain issues and global warming concerns. This traditional approach of evaluating one policy at a time is too simplistic to serve as a framework for electric utilities making major capital investment and fuel procurement decisions to comply with various environmental requirements. Potential Climate change regulation can affect acid rain compliance decisions, and acid rain compliance decisions will affect future GHG emissions. This paper explores two categories of linkages between these different environmental issues. First, the assumptions one makes regarding future climate change policies can have a profound impact on the economic attractiveness of various acid rain compliance strategies. Second, decisions regarding acid rain compliance strategy can have greenhouse gas implications that might prove more or less difficult to address in future climate change legislation.

  2. The acid rain debate. Scientific, economic, and political dimensions

    SciTech Connect

    Yanarella, E.J.

    1985-01-01

    This collection of essays focuses on the political and legal aspects of the acid rain debate, the policy options for resolving the controversy, and the international dimensions of acid rain control. The contributors highlight concerns drawn primarily from the developing study of acid rain in political science, economics, public administration, and policy analysis - concerns that are the focal point of the public debate over the nature, impact, and cost of acid rain and the mitigation of its effects. The book complements the body of research from the natural sciences and responds to the need for applied study to help resolve the current policy stalemate on this environmental issue. The essays are supplemented by a comprehensive annotated bibliography on acid rain and relevant social science research.

  3. Response of citrus and other selected plant species to simulated HCL - acid rain

    NASA Technical Reports Server (NTRS)

    Knott, W. M.; Heagle, A. S.

    1980-01-01

    Mature valencia orange trees were sprayed with hydrochloric acid solutions (pH 7.8, 2.0, 1.0, and 0.5) in the field at the full bloom stage and at one month after fruit set. Potted valencia orange and dwarf citrus trees, four species of plants native to Merritt Island, and four agronomic species were exposed to various pH levels of simulated acid rain under controlled conditions. The acid rain was generated from dilutions of hydrochloric acid solutions or by passing water through an exhaust generated by burning solid rocket fuel. The plants were injured severely at pH levels below 1.0, but showed only slight injury at pH levels of 2.0 and above. Threshold injury levels were between 2.0 and 3.0 pH. The sensitivity of the different plant species to acid solutions was similar. Foliar injury symptoms were representative of acid rain including necrosis of young tissue, isolated necrotic spots or patches, and leaf abscission. Mature valencia orange trees sprayed with concentrations of 1.0 pH and 0.5 pH in the field had reduced fruit yields for two harvests after the treatment. All experimental trees were back to full productivity by the third harvest after treatment.

  4. Acid rain phenomenon in niger delta region of Nigeria: economic, biodiversity, and public health concern.

    PubMed

    Nduka, J K C; Orisakwe, O E; Ezenweke, L O; Ezenwa, T E; Chendo, M N; Ezeabasili, N G

    2008-08-28

    Rain samples were collected from Warri and Port Harcourt, two major oil-producing cities of Nigeria in April-June, July-August, and September-October 2005 and 2006. Awka, a "non-oil" city was used as control. Samples were collected from three points, using clean plastic basins fastened to a table, 2 m above ground level and 115 m away from tall buildings and trees. Water samples were filtered and acidity determined using digital pH meter. The results show that the rain samples were acidic. The pH values for the 2 years under study show that the rainfall in Warri was more acidic than that of Port Harcourt. Oil exploration and other anthropogenic sources may be responsible for the acid rain in the Niger Delta region of Nigeria.

  5. Red herring in acid rain research

    SciTech Connect

    Havas, M.; Hutchinson, T.C.; Likens, G.E.

    1984-06-01

    Five common misconceptions, red herrings, regarding the effects of acid deposition on aquatic ecosystems are described in an attempt to clarify some of the confusion they have created. These misconceptions are the following: Bog lakes have been acidic for thousands of years; thus the acidification of lakes is not a recent phenomenon. The early methods for measuring pH are in error; therfore, no statements can be made regarding historical trends. Acidification of lakes and streams results from changed land use practices (forestry, agriculture, animal husbandry) and not acid deposition. The decrease in fish populations is caused by overfishing, disease, and water pollution, not acidification. Because lakes that receive identical rainfall can have considerable different pHs, regional lake acidification cannot be due to acid precipitation. It is easy to suggest a whole series of alternative, and often unlikely, explanations of the causes and consequences of acid deposition. These keep scientists busy for years assembling and examining data only to conclude that the explanation is not valid. These tactics cause, and perhaps are designed to cause, continuous delay in remedial action. They fail to take into account the large body of information that deals with the sources of the acid deposition and the seriousness of its effects.

  6. Acid rain reduced in Eastern United States

    SciTech Connect

    Lynch, J.A.; Bowersox, V.C.; Grimm, J.W.

    2000-03-15

    Concentrations of sulfate (SO{sub 4}{sup 2{minus}}) and free hydrogen ions (H{sup +}) in precipitation decreased from 10% to 25% over a large area of the Eastern US from 1995 through 1997 as compared to the previous 12-year (1983--1994) reference period. These decreases were unprecedented in magnitude and spatial extent. In contrast, nitrate (NO{sub 3}{sup {minus}}) concentrations generally did not change over this period. The largest decreases in both H{sup +} and SO{sub 4}{sup 2{minus}} concentrations, which nearly mimicked one another, occurred in and downwind of the Ohio River Valley, the same area where Title 4 of the 1990 Clean Air Act Amendments (CAAA) set limitations on sulfur dioxide (SO{sub 2}) emissions from a large number of utility-owned coal-fired sources. Phase 1 of the CAAA required that these limitations be met by January 1, 1995. On the basis of their analysis of precipitation chemistry and emissions data, the authors conclude that significant declines in acid rain occurred in many parts of the Eastern US from 1995 through 1997 because of large reductions in SO{sub 2} emissions in this region and a corresponding reduction in SO{sub 4}{sup 2{minus}} concentrations in precipitation.

  7. Changes in poultry litter toxicity with simulated acid rain

    SciTech Connect

    Gupta, G.; Krishnamurthy, S. )

    1991-01-01

    The Delmarva Peninsula on the Eastern Shore of Maryland ranks 4th in the nation in poultry production and generates 9,500 metric tons of poultry manure/litter per day. The poultry litter contains many macro and micro nutrients and is an excellent source of fertilizer. The litter also contains antibiotics, heavy metals, hormones and many microorganisms. Land application of this litter has been the only means of its utilization and disposal. With rainfall, surface water run-off (leachate), from land on which litter has been applied, reaches the Cheasapeake Bay from this region. This leachate with its high organic and inorganic salt contents and high biochemical oxygen demand can severely disrupt the aquatic life and cause fish kills. The objective of this research was to study the effect of simulated acid rain (pH 3, 4 and 5) on the toxicity of poultry litter extracts.

  8. [Effects of simulated acid rain on seed germination and seedling growth of different type corn Zea mays].

    PubMed

    Zhang, Hai-Yan

    2013-06-01

    Taking normal corn, waxy corn, pop corn, and sweet corn as test materials, this paper studied their seed germination and seedling growth under effects of simulated acid rain (pH 6.0, 5.0, 4.0, 3.0, 2.0, and 1.0). Simulated acid rain at pH 2.0-5.0 had no significant effects on the seed germination and seedling growth, but at pH 1.0, the germination rate of normal corn, waxy corn, pop corn, and sweet corn was 91.3%, 68.7%, 27.5%, and 11.7%, respectively. As compared with those at pH 6.0 (CK), the germination rate, germination index, vigor index, germination velocity, shoot height, root length, shoot and root dry mass, and the transformation rate of stored substances at pH 1.0 had significant decrease, and the average germination time extended apparently. At pH 1.0, the effects of acid rain were greater at seedling growth stage than at germination stage, and greater on underground part than on aboveground part. Due to the differences in gene type, normal corn and waxy corn had the strongest capability against acid rain, followed by pop corn, and sweet corn. It was suggested that corn could be categorized as an acid rain-tolerant crop, the injury threshold value of acid rain was likely between pH 1.0 and pH 2.0, and normal corn and waxy corn would be prioritized for planting in acid rain-stricken area.

  9. Antioxidant response of soybean seedlings to joint stress of lanthanum and acid rain.

    PubMed

    Liang, Chanjuan; Wang, Weimin

    2013-11-01

    Excess of rare earth elements in soil can be a serious environmental stress on plants, in particular when acid rain coexists. To understand how such a stress affects plants, we studied antioxidant response of soybean leaves and roots exposed to lanthanum (0.06, 0.18, and 0.85 mmol L(-1)) under acid rain conditions (pH 4.5 and 3.0). We found that low concentration of La3+ (0.06 mmol L(-1)) did not affect the activity of antioxidant enzymes (catalase and peroxidase) whereas high concentration of La3+ (≥0.18 mmol L(-1)) did. Compared to treatment with acid rain (pH 4.5 and pH 3.0) or La3+ alone, joint stress of La3+ and acid rain affected more severely the activity of catalase and peroxidase, and induced more H2O2 accumulation and lipid peroxidation. When treated with high level of La3+ (0.85 mmol L(-1)) alone or with acid rain (pH 4.5 and 3.0), roots were more affected than leaves regarding the inhibition of antioxidant enzymes, physiological function, and growth. The severity of oxidative damage and inhibition of growth caused by the joint stress associated positively with La3+ concentration and soil acidity. These results will help us understand plant response to joint stress, recognize the adverse environmental impact of rare earth elements in acidic soil, and develop measures to eliminate damage caused by such joint stress.

  10. Combined effects of simulated acid rain and lanthanum chloride on chloroplast structure and functional elements in rice.

    PubMed

    Hu, Huiqing; Wang, Lihong; Zhou, Qing; Huang, Xiaohua

    2016-05-01

    Acid rain and rare earth element (REE) pollution exist simultaneously in many agricultural regions. However, how REE pollution and acid rain affect plant growth in combination remains largely unknown. In this study, the combined effects of simulated acid rain and lanthanum chloride (LaCl3) on chloroplast morphology, chloroplast ultrastructure, functional element contents, chlorophyll content, and the net photosynthetic rate (P n) in rice (Oryza sativa) were investigated by simulating acid rain and rare earth pollution. Under the combined treatment of simulated acid rain at pH 4.5 and 0.08 mM LaCl3, the chloroplast membrane was smooth, proteins on this membrane were uniform, chloroplast structure was integrated, and the thylakoids were orderly arranged, and simulated acid rain and LaCl3 exhibited a mild antagonistic effect; the Mg, Ca, Mn contents, the chlorophyll content, and the P n increased under this combined treatment, with a synergistic effect of simulated acid rain and LaCl3. Under other combined treatments of simulated acid rain and LaCl3, the chloroplast membrane surface was uneven, a clear "hole" was observed on the surface of chloroplasts, and the thylakoids were dissolved and loose; and the P n and contents of functional elements (P, Mg, K, Ca, Mn, Fe, Ni, Cu, Zn and Mo) and chlorophyll decreased. Under these combined treatments, simulated acid rain and LaCl3 exhibited a synergistic effect. Based on the above results, a model of the combined effects of simulated acid rain and LaCl3 on plant photosynthesis was established in order to reveal the combined effects on plant photosynthesis, especially on the photosynthetic organelle-chloroplast. Our results would provide some references for further understanding the mechanism of the combined effects of simulated acid rain and LaCl3 on plant photosynthesis.

  11. Air quality monitor and acid rain networks

    NASA Technical Reports Server (NTRS)

    Rudolph, H.

    1980-01-01

    The air quality monitor program which consists of two permanent air monitor stations (PAMS's) and four mobile shuttle pollutant air monitor stations (SPAMS's) is evaluated. The PAMS measures SO sub X, NO sub X particulates, CO, O3, and nonmethane hydrocarbons. The SPAMS measures O3, SO2, HCl, and particulates. The collection and analysis of data in the rain monitor program are discussed.

  12. Alterations in cytosol free calcium in horseradish roots simultaneously exposed to lanthanum(III) and acid rain.

    PubMed

    Zhang, Xuanbo; Wang, Lihong; Zhou, Anhua; Zhou, Qing; Huang, Xiaohua

    2016-04-01

    The extensive use of rare earth elements (REEs) has increased their environmental levels. REE pollution concomitant with acid rain in many agricultural regions can affect crop growth. Cytosol free calcium ions (Ca(2+)) play an important role in almost all cellular activities. However, no data have been reported regarding the role of cytosol free Ca(2+) in plant roots simultaneously exposed to REE and acid rain. In this study, the effects of exposures to lanthanum(III) and acid rain, independently and in combination, on cytosol free Ca(2+) levels, root activity, metal contents, biomass, cytosol pH and La contents in horseradish roots were investigated. The simultaneous exposures to La(III) and acid rain increased or decreased the cytosol free Ca(2+) levels, depending on the concentration of La(III), and these effects were more evident than independent exposure to La(III) or acid rain. In combined exposures, cytosol free Ca(2+) played an important role in the regulation of root activity, metal contents and biomass. These roles were closely related to La(III) dose, acid rain strength and treatment mode (independent exposure or simultaneous exposure). A low concentration of La(III) (20 mg L(-1)) could alleviate the adverse effects on the roots caused by acid rain, and the combined exposures at higher concentrations of La(III) and acid rain had synergic effects on the roots.

  13. Acid Rain. Activities for Grades 4 to 12. A Teacher's Guide.

    ERIC Educational Resources Information Center

    Wood, David; Bryant, Jeannette

    This teacher's guide on acid rain is divided into three study areas to explain: (1) what causes acid rain; (2) what problems acid rain has created; and (3) what teachers and students can do to help combat acid rain. Instructions for activities within the study areas include suggested grade levels, objectives, materials needed, and directions for…

  14. 40 CFR 72.31 - Information requirements for Acid Rain permit applications.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Information requirements for Acid Rain... (CONTINUED) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Acid Rain Permit Applications § 72.31 Information requirements for Acid Rain permit applications. A complete Acid Rain permit application shall include...

  15. 40 CFR 72.31 - Information requirements for Acid Rain permit applications.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 17 2014-07-01 2014-07-01 false Information requirements for Acid Rain... (CONTINUED) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Acid Rain Permit Applications § 72.31 Information requirements for Acid Rain permit applications. A complete Acid Rain permit application shall include...

  16. 40 CFR 72.31 - Information requirements for Acid Rain permit applications.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 17 2012-07-01 2012-07-01 false Information requirements for Acid Rain... (CONTINUED) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Acid Rain Permit Applications § 72.31 Information requirements for Acid Rain permit applications. A complete Acid Rain permit application shall include...

  17. 40 CFR 72.31 - Information requirements for Acid Rain permit applications.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Information requirements for Acid Rain... (CONTINUED) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Acid Rain Permit Applications § 72.31 Information requirements for Acid Rain permit applications. A complete Acid Rain permit application shall include...

  18. Acid Rain: A Teacher's Guide. Activities for Grades 4 to 12.

    ERIC Educational Resources Information Center

    National Wildlife Federation, Washington, DC.

    This guide on acid rain for elementary and secondary students is divided into three study areas: (1) What Causes Acid Rain; (2) What Problems Acid Rain Has Created; (3) How You and Your Students Can Help Combat Acid Rain. Each section presents background information and a series of lessons pertaining to the section topic. Activities include…

  19. 40 CFR 72.31 - Information requirements for Acid Rain permit applications.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Information requirements for Acid Rain... (CONTINUED) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Acid Rain Permit Applications § 72.31 Information requirements for Acid Rain permit applications. A complete Acid Rain permit application shall include...

  20. [Combined injured effects of acid rain and lanthanum on growth of soybean seedling].

    PubMed

    Liang, Chan-juan; Pan, Dan-yun; Xu, Qiu-rong; Zhou, Qing

    2010-07-01

    Combined effects of acid rain and lanthanum on growth of soybean seedling (Glycine max) and its inherent mechanism were studied in this paper. Compared with treatments by simulated acid rain (pH 3.0, 3.5, 4.5) or rare earth La(III) (60, 100 and 300 mg x L(-1)), the decrease degree of growth parameters in combined treatments was higher, indicating that there were a synergistic effects between acid rain and La. Moreover,the inhibition effects of acid rain and La(III) were more obvious when pH value of acid rain was lower or the concentration of La(III) was higher. The changes of photosynthetic parameters were similar to those of growth, but the decrease degree of each parameter was not same in the same treatment group. The decrease degree of optimal PSII photochemical efficiency (Fv/Fm) and chlorophyll content (Chl) were 9.35%-22.75% and 9.14%-24.53%, respectively, lower than that of photosynthetic rate Pn (22.78%-84.7%), Hill reaction rate (15.52%-73.38%) and Mg2+ -ATPase activity (14.51%-71.54%), showing that the sensitivity of photosynthetic parameters to the combined factors was different. Furthermore, relative analysis showed that the change of Pn were mainly affected by Hill reaction rate and Mg2+ -ATPase activity, and was less influenced by Chl and Fv/Fm. It indicates that the effect of acid rain and La on each reaction in photosynthesis was different, and the inhibition of combined treatments on photosynthesis in plants was one of the main factors affecting growth of plant.

  1. Characterization of heavy metal desorption from road-deposited sediment under acid rain scenarios.

    PubMed

    Zhao, Bo; Liu, An; Wu, Guangxue; Li, Dunzhu; Guan, Yuntao

    2017-01-01

    Road-deposited sediments (RDS) on urban impervious surfaces are important carriers of heavy metals. Dissolved heavy metals that come from RDS influenced by acid rain, are more harmful to urban receiving water than particulate parts. RDS and its associated heavy metals were investigated at typical functional areas, including industrial, commercial and residential sites, in Guangdong, Southern China, which was an acid rain sensitive area. Total and dissolved heavy metals in five particle size fractions were analyzed using a shaking method under acid rain scenarios. Investigated heavy metals showed no difference in the proportion of dissolved fraction in the solution under different acid rain pHs above 3.0, regardless of land use. Dissolved loading of heavy metals related to organic carbon content were different in runoff from main traffic roads of three land use types. Coarse particles (>150μm) that could be efficiently removed by conventional street sweepers, accounted for 55.1%-47.1% of the total dissolved metal loading in runoff with pH3.0-5.6. The obtained findings provided a significant scientific basis to understand heavy metal release and influence of RDS grain-size distribution and land use in dissolved heavy metal pollution affected by acid rain.

  2. Effects of simulated acid rain on microbial characteristics in a lateritic red soil.

    PubMed

    Xu, Hua-qin; Zhang, Jia-en; Ouyang, Ying; Lin, Ling; Quan, Guo-ming; Zhao, Ben-liang; Yu, Jia-yu

    2015-11-01

    A laboratory experiment was performed to examine the impact of simulated acid rain (SAR) on nutrient leaching, microbial biomass, and microbial activities in a lateritic red soil in South China. The soil column leaching experiment was conducted over a 60-day period with the following six SAR pH treatments (levels): 2.5, 3.0, 3.5, 4.0, 4.5, and 5.0 and one control treatment (pH = 7). Compared with the control treatment, the concentrations of soil organic matter, total nitrogen, total phosphorus, total potassium, soil microbial biomass carbon (MBC), soil microbial biomass nitrogen (MBN), and average well color density (AWCD) in the Ecoplates were all significantly decreased by leaching with SAR at different pH levels. The decrease in MBC and MBN indicated that acid rain reduced the soil microbial population, while the decrease in AWCD revealed that acid rain had a negative effect on soil bacterial metabolic function. Soil basal respiration increased gradually from pH 4.0 to 7.0 but decreased dramatically from pH 2.5 to 3.0. The decrease in soil nutrient was the major reason for the change of soil microbial functions. A principal component analysis showed that the major carbon sources used by the bacteria were carbohydrates and carboxylic acids.

  3. Cation deficiency in the atmosphere as a probable cause of acid rains in North America

    NASA Astrophysics Data System (ADS)

    Varma, G. S.

    In North America, where almost every shower is acidic (pH < 5.65), the proper causes have been studied. It was observed that the main cause behind the acidic rains is the alkali deficient environment which fails to neutralize the acid traces formed in the atmosphere by anthropogenic, biogenic and agricultural activity and not the increase in anions in the atmosphere as was speculated earlier by many workers. The data of 12 BAPMoN stations of America from the period 1974-1980 have revealed that, at most of the stations, the trends of cations are declining and in most cases the concentration of anions have also decreased. Thus the environment in the U.S. is becoming cleaner day by day. The pH values have been correlated with both the 'cations' and 'anions' separately (Fig. 1) for all 12 the BAPMoN stations and strong positive correlations have been observed between pH and cations ( rc) while poor correlations were found for anions ( ra) which reveals that pH of rain is more influenced by cation's activity in the atmosphere which are decreasing rapidly as a result of which the rains in North America are found to be acidic. It is not due to an increase in anions caused by industrialization and automobile emissions.

  4. Acid rain and its environmental effects: Recent scientific advances

    NASA Astrophysics Data System (ADS)

    Burns, Douglas A.; Aherne, Julian; Gay, David A.; Lehmann, Christopher M. B.

    2016-12-01

    The term 'acid rain' refers to atmospheric deposition of acidic constituents that impact the earth as rain, snow, particulates, gases, and vapor. Acid rain was first recognized by Ducros (1845) and subsequently described by the English chemist Robert Angus Smith (Smith, 1852) whose pioneering studies linked the sources to industrial emissions and included early observations of deleterious environmental effects (Smith, 1872). Smith's work was largely forgotten until the mid-20th century when observations began to link air pollution to the deposition of atmospheric sulfate (SO42-) and other chemical constituents, first near the metal smelter at Sudbury, Ontario, Canada, and later at locations in Europe, North America, and Australia (Gorham, 1961). Our modern understanding of acid rain as an environmental problem caused largely by regional emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) stems from observations in the 1960s and early 1970s in Sweden by Svante Odén (Odén, 1976), and in North America by Gene Likens and colleagues (Likens and Bormann, 1974). These scientists and many who followed showed the link to emissions from coal-fired power plants and other industrial sources, and documented the environmental effects of acid rain such as the acidification of surface waters and toxic effects on vegetation, fish, and other biota.

  5. The regional costs and benefits of acid rain control

    SciTech Connect

    Berkman, M.P.

    1991-01-01

    Congress recently enacted acid rain control legislation as part of the 1990 Clean Air Act Amendments following a decade-long debate among disparate regional interests. Although Congress succeeded in drafting a law acceptable to all regions, the regional costs and benefits of the legislation remain uncertain. The research presented here attempts to estimate the regional costs and benefits and the economic impacts of acid rain controls. These estimates are made using a modeling system composed of econometric, linear programming and input-output models. The econometric and linear programming components describe markets for electricity and coal. The outputs of these components including capital investment, electricity demand, and coal production are taken as exogenous inputs by a multiregional input-output model. The input-output model produces estimates of changes in final demand, gross output, and employment. The utility linear programming model also predicts sulfur dioxide emissions (an acid-rain precursor). According to model simulations, the costs of acid rain control exceed the benefits for many regions including several regions customarily thought to be the major beneficiaries of acid rain control such as New England.

  6. Impacts of simulated acid rain on recalcitrance of two different soils.

    PubMed

    Dai, Zhongmin; Liu, Xingmei; Wu, Jianjun; Xu, Jianming

    2013-06-01

    Laboratory experiments were conducted to estimate the impacts of simulated acid rain (SAR) on recalcitrance in a Plinthudult and a Paleudalfs soil in south China, which were a variable and a permanent charge soil, respectively. Simulated acid rains were prepared at pH 2.0, 3.5, 5.0, and 6.0, by additions of different volumes of H2SO4 plus HNO3 at a ratio of 6 to 1. The leaching period was designed to represent 5 years of local annual rainfall (1,200 mm) with a 33 % surface runoff loss. Both soils underwent both acidification stages of (1) cation exchange and (2) mineral weathering at SAR pH 2.0, whereas only cation exchange occurred above SAR pH 3.5, i.e., weathering did not commence. The cation exchange stage was more easily changed into that of mineral weathering in the Plinthudult than in the Paleudalfs soil, and there were some K(+) and Mg(2+) ions released on the stages of mineral weathering in the Paleudalfs soil. During the leaching, the release of exchangeable base cations followed the order Ca(2+) >K(+) >Mg(2+) >Na(+) for the Plinthudult and Ca(2+) >Mg(2+) >Na(+) >K(+) for the Paleudalfs soil. The SARs above pH 3.5 did not decrease soil pH or pH buffering capacity, while the SAR at pH 2.0 decreased soil pH and the buffering capacity significantly. We conclude that acid rain, which always has a pH from 3.5 to 5.6, only makes a small contribution to the acidification of agricultural soils of south China in the short term of 5 years. Also, Paleudalfs soils are more resistant to acid rain than Plinthudult soils. The different abilities to prevent leaching by acid rain depend upon the parent materials, types of clay minerals, and soil development degrees.

  7. [Reponses of sugar metabolism in seed germination of three various acid-fast plants to acid rain].

    PubMed

    Wang, Li-Hong; Zhou, Qing; Zeng, Qing-Ling

    2008-03-01

    Responses of sugar metabolism during germination of rice (O. sativa ), wheat (T. aestivum) and rape (B. chinensis var. oleifera) seeds to simulated acid rain (pH 2.0, pH 2.5, pH 3.0, pH 3.5, pH 4.0, pH 4.5, pH 5.0) were investigated. The purpose was to clarify the mechanism of acid rain affecting seed germination. The results show that the alpha-amylase activity, contents of soluble sugar and reducing sugar of the rice, wheat and rape seeds decrease with increased stress level (pH 5.0 - 2.0), and are lower than CK. The response order of three indexes to stress level of acid rain is that rice (pH 3.5 - 4.0/53.88% - 77.7%) is smaller than wheat (pH 3.5 - 4.5/58.60% - 89.41%), and rape (pH 4.0 - 5.0/60.14% - 100%) is the smallest, alpha-amylase activity, contents of soluble sugar and reducing sugar of rice increase with prolonged stress time, but the three indexes of wheat and rape increase at first, and then decrease. In the same stress time (3 - 7 d), the three indexes of the three species for all treatment groups are lower than CK, and decrease with increased stress level. The stress time when the maximum damage of a-amylase activity, contents of soluble sugar and reducing sugar appeared is that rice (7 d, 7 d, 7 d) > wheat (7 d, 6 d, 5 d) > rape (3 d, 7 d, 5 d). Responses of three indexes to stress level and stress time of acid rain show that the ability of sugar metabolism resisting acid rain is that rice is stronger than wheat and rape is the worst, and the difference in sugar metabolism of 3 species is one of the internal reasons why the germination indexes behave differently.

  8. Swedish scientists take acid-rain research to developing nations

    SciTech Connect

    Abate, T.

    1995-12-01

    In the realm of acid-rain research, Sweden looms large on the world stage. It is the country where scientists first proved more than 30 years ago that airborne chemicals could and did cross international boundaries to acidify lakes and forests far from where the pollution was generated. Now, Swedish scientists are leading an international effort to map acid-rain patterns in the developing countries of Asia, where new industrial activity seems to be recreating problems that European and North American policy makers have already taken steps to solve. Topics covered in this article include acid rain on the rise in Asia; visualizing and validating the data; funding as the key to steady research.

  9. Acid rain and electric utilities: Permits, allowances, monitoring and meteorology

    SciTech Connect

    Dayal, P.

    1995-12-31

    This conference was held January 23--25, 1995 in Tempe, Arizona. The purpose of the conference was to provide a multidisciplinary forum for exchange of state-of-the-art information on the environmental effects electric utilities have in relation to air pollution and acid rain. Attention is focused on many of the permitting and monitoring issues facing the electric utilities industry. Sulfur dioxide allowances, Title IV and Title V issues, Acid Rain Program implementation and Continuing Emissions Monitoring Systems (CEMS) are some of the relevant topics covered in this proceedings. Individual papers have been processed separately for inclusion in the appropriate data bases.

  10. Response of soil respiration to acid rain in forests of different maturity in southern China.

    PubMed

    Liang, Guohua; Liu, Xingzhao; Chen, Xiaomei; Qiu, Qingyan; Zhang, Deqiang; Chu, Guowei; Liu, Juxiu; Liu, Shizhong; Zhou, Guoyi

    2013-01-01

    The response of soil respiration to acid rain in forests, especially in forests of different maturity, is poorly understood in southern China despite the fact that acid rain has become a serious environmental threat in this region in recent years. Here, we investigated this issue in three subtropical forests of different maturity [i.e. a young pine forest (PF), a transitional mixed conifer and broadleaf forest (MF) and an old-growth broadleaved forest (BF)] in southern China. Soil respiration was measured over two years under four simulated acid rain (SAR) treatments (CK, the local lake water, pH 4.5; T1, water pH 4.0; T2, water pH 3.5; and T3, water pH 3.0). Results indicated that SAR did not significantly affect soil respiration in the PF, whereas it significantly reduced soil respiration in the MF and the BF. The depressed effects on both forests occurred mostly in the warm-wet seasons and were correlated with a decrease in soil microbial activity and in fine root biomass caused by soil acidification under SAR. The sensitivity of the response of soil respiration to SAR showed an increasing trend with the progressive maturity of the three forests, which may result from their differences in acid buffering ability in soil and in litter layer. These results indicated that the depressed effect of acid rain on soil respiration in southern China may be more pronounced in the future in light of the projected change in forest maturity. However, due to the nature of this field study with chronosequence design and the related pseudoreplication for forest types, this inference should be read with caution. Further studies are needed to draw rigorous conclusions regarding the response differences among forests of different maturity using replicated forest types.

  11. Response of Soil Respiration to Acid Rain in Forests of Different Maturity in Southern China

    PubMed Central

    Chen, Xiaomei; Qiu, Qingyan; Zhang, Deqiang; Chu, Guowei; Liu, Juxiu; Liu, Shizhong; Zhou, Guoyi

    2013-01-01

    The response of soil respiration to acid rain in forests, especially in forests of different maturity, is poorly understood in southern China despite the fact that acid rain has become a serious environmental threat in this region in recent years. Here, we investigated this issue in three subtropical forests of different maturity [i.e. a young pine forest (PF), a transitional mixed conifer and broadleaf forest (MF) and an old-growth broadleaved forest (BF)] in southern China. Soil respiration was measured over two years under four simulated acid rain (SAR) treatments (CK, the local lake water, pH 4.5; T1, water pH 4.0; T2, water pH 3.5; and T3, water pH 3.0). Results indicated that SAR did not significantly affect soil respiration in the PF, whereas it significantly reduced soil respiration in the MF and the BF. The depressed effects on both forests occurred mostly in the warm-wet seasons and were correlated with a decrease in soil microbial activity and in fine root biomass caused by soil acidification under SAR. The sensitivity of the response of soil respiration to SAR showed an increasing trend with the progressive maturity of the three forests, which may result from their differences in acid buffering ability in soil and in litter layer. These results indicated that the depressed effect of acid rain on soil respiration in southern China may be more pronounced in the future in light of the projected change in forest maturity. However, due to the nature of this field study with chronosequence design and the related pseudoreplication for forest types, this inference should be read with caution. Further studies are needed to draw rigorous conclusions regarding the response differences among forests of different maturity using replicated forest types. PMID:23626790

  12. Acid loading test (pH)

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003615.htm Acid loading test (pH) To use the sharing features on this page, please enable JavaScript. The acid loading test (pH) measures the ability of the ...

  13. Innovative role of statistics in acid rain performance testing

    SciTech Connect

    Warren-Hicks, W.; Etchison, T.; Lieberman, E.R.

    1995-12-31

    Title IV of the Clean Air Act Amendments (CAAAs) of 1990 mandated that affected electric utilities reduce sulfur dioxide (SO{sub 2}) and nitrogen oxide (NO{sub x}) emissions, the primary precursors of acidic deposition, and included an innovative market-based SO{sub 2} regulatory program. A central element of the Acid Rain Program is the requirement that affected utility units install CEMS. This paper describes how the Acid Rain Regulations incorporated statistical procedures in the performance tests for continuous emissions monitoring systems (CEMS) and how statistical analysis was used to assess the appropriateness, stringency, and potential impact of various performance tests and standards that were considered for inclusion in the Acid Rain Regulations. Described here is the statistical analysis that was used to set a relative accuracy standard, establish the calculation procedures for filling in missing data when a monitor malfunctions, and evaluate the performance tests applied to petitions for alternative monitoring systems. The paper concludes that the statistical evaluations of proposed provisions of the Acid Rain Regulations resulted in the adoption of performance tests and standards that were scientifically substantiated, workable, and effective.

  14. Acid rain and its environmental effects: Recent scientific advances

    USGS Publications Warehouse

    Burns, Douglas A.; Aherne, Julian; Gay, David A.; Lehmann, Christopher M.B.

    2016-01-01

    The term ‘acid rain’ refers to atmospheric deposition of acidic constituents that impact the earth as rain, snow, particulates, gases, and vapor. Acid rain was first recognized by Ducros (1845) and subsequently described by the English chemist Robert Angus Smith (Smith, 1852) whose pioneering studies linked the sources to industrial emissions and included early observations of deleterious environmental effects (Smith, 1872). Smith's work was largely forgotten until the mid-20th century when observations began to link air pollution to the deposition of atmospheric sulfate (SO42−) and other chemical constituents, first near the metal smelter at Sudbury, Ontario, Canada, and later at locations in Europe, North America, and Australia (Gorham, 1961). Our modern understanding of acid rain as an environmental problem caused largely by regional emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) stems from observations in the 1960s and early 1970s in Sweden by Svante Odén (Odén, 1976), and in North America by Gene Likens and colleagues (Likens and Bormann, 1974). These scientists and many who followed showed the link to emissions from coal-fired power plants and other industrial sources, and documented the environmental effects of acid rain such as the acidification of surface waters and toxic effects on vegetation, fish, and other biota.

  15. [Effects of simulated acid rain on oilseed rape (Brassica napus) physiological characteristics at flowering stage and yield].

    PubMed

    Cao, Chun-Xin; Zhou, Qin; Han, Liang-Liang; Zhang, Pei; Jiang, Hai-Dong

    2010-08-01

    A pot experiment was conducted to study the effects of different acidity simulated acid rain on the physiological characteristics at flowering stage and yield of oilseed rape (B. napus cv. Qinyou 9). Comparing with the control (pH 6.0), weak acidity (pH = 4.0-5.0) simulated acid rain stimulated the rape growth to some extent, but had less effects on the plant biomass, leaf chlorophyll content, photosynthetic characteristics, and yield. With the further increase of acid rain acidity, the plant biomass, leaf chlorophyll content, photosynthetic rate, antioxidative enzyme activities, and non-enzyme antioxidant contents all decreased gradually, while the leaf malonyldialdehyde (MDA) content and relative conductivity increased significantly. As the results, the pod number per plant, seed number per pod, seed weight, and actual yield decreased. However, different yield components showed different sensitivity to simulated acid rain. With the increasing acidity of simulated acid rain, the pod number per plant and the seed number per pod decreased significantly, while the seed weight was less affected.

  16. A Gaming Approach to the Acid Rain Problem.

    ERIC Educational Resources Information Center

    Baba, Norio; And Others

    1984-01-01

    Describes an educational microcomputer gaming system for dealing with the acid rain problem in Western Europe and discusses its objectives, rules, problems, and future perspectives. Usefulness of gaming as an operational aid in formulating appropriate energy policies worldwide is emphasized. (MBR)

  17. Impacts of simulated acid rain on soil enzyme activities in a latosol.

    PubMed

    Ling, Da-Jiong; Huang, Qian-Chun; Ouyang, Ying

    2010-11-01

    Acid rain pollution is a serious environmental problem in the world. This study investigated impacts of simulated acid rain (SAR) upon four types of soil enzymes, namely the catalase, acid phosphatase, urease, and amylase, in a latosol. Latosol is an acidic red soil and forms in the tropical rainforest biome. Laboratory experiments were performed by spraying the soil columns with the SAR at pH levels of 2.5, 3.0, 3.5., 4.0, 4.5, 5.0, and 7.0 (control) over a 20-day period. Mixed results were obtained in enzyme activities for different kinds of enzymes under the influences of the SAR. The catalase activities increased rapidly from day 0 to 5, then decreased slightly from day 5 to 15, and finally decreased sharply to the end of the experiments, whereas the acid phosphatase activities decreased rapidly from day 0 to 5, then increased slightly from day 5 to 15, and finally decreased dramatically to the end of the experiments. A decrease in urease activities was observed at all of the SAR pH levels for the entire experimental period, while an increase from day 0 to 5 and then a decrease from day 5 to 20 in amylase activities were observed at all of the SAR pH levels. In general, the catalase, acid phosphatase, and urease activities increased with the SAR pH levels. However, the maximum amylase activity was found at pH 4.0 and decreased as the SAR pH increased from 4.0 to 5.0 or decreased from 4.0 to 2.5. It is apparent that acid rain had adverse environmental impacts on soil enzyme activities in the latosol. Our study further revealed that impacts of the SAR upon soil enzyme activities were in the following order: amylase>catalase>acid phosphatase>urease. These findings provide useful information on better understanding and managing soil biological processes in the nature under the influence of acid rains.

  18. 40 CFR 72.71 - Acceptance of State Acid Rain programs-general.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Acceptance of State Acid Rain programs... PROGRAMS (CONTINUED) PERMITS REGULATION Acid Rain Phase II Implementation § 72.71 Acceptance of State Acid... State Acid Rain program meeting the requirements of §§ 72.72 and 72.73. (b) The Administrator...

  19. 40 CFR 72.69 - Issuance and effective date of acid rain permits.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Federal Acid Rain Permit Issuance Procedures § 72.69 Issuance and effective date of acid rain permits. (a) After the close of the public comment period, the Administrator will issue or deny an Acid Rain permit. The Administrator will serve a copy of any Acid...

  20. 40 CFR 72.69 - Issuance and effective date of acid rain permits.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Federal Acid Rain Permit Issuance Procedures § 72.69 Issuance and effective date of acid rain permits. (a) After the close of the public comment period, the Administrator will issue or deny an Acid Rain permit. The Administrator will serve a copy of any Acid...

  1. 40 CFR 72.69 - Issuance and effective date of acid rain permits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Federal Acid Rain Permit Issuance Procedures § 72.69 Issuance and effective date of acid rain permits. (a) After the close of the public comment period, the Administrator will issue or deny an Acid Rain permit. The Administrator will serve a copy of any Acid...

  2. 40 CFR 72.71 - Acceptance of State Acid Rain programs-general.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 17 2012-07-01 2012-07-01 false Acceptance of State Acid Rain programs... PROGRAMS (CONTINUED) PERMITS REGULATION Acid Rain Phase II Implementation § 72.71 Acceptance of State Acid... State Acid Rain program meeting the requirements of §§ 72.72 and 72.73. (b) The Administrator...

  3. 40 CFR 72.71 - Acceptance of State Acid Rain programs-general.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 17 2014-07-01 2014-07-01 false Acceptance of State Acid Rain programs... PROGRAMS (CONTINUED) PERMITS REGULATION Acid Rain Phase II Implementation § 72.71 Acceptance of State Acid... State Acid Rain program meeting the requirements of §§ 72.72 and 72.73. (b) The Administrator...

  4. 40 CFR 72.69 - Issuance and effective date of acid rain permits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Federal Acid Rain Permit Issuance Procedures § 72.69 Issuance and effective date of acid rain permits. (a) After the close of the public comment period, the Administrator will issue or deny an Acid Rain permit. The Administrator will serve a copy of any Acid...

  5. 40 CFR 72.69 - Issuance and effective date of acid rain permits.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Federal Acid Rain Permit Issuance Procedures § 72.69 Issuance and effective date of acid rain permits. (a) After the close of the public comment period, the Administrator will issue or deny an Acid Rain permit. The Administrator will serve a copy of any Acid...

  6. 40 CFR 72.71 - Acceptance of State Acid Rain programs-general.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Acceptance of State Acid Rain programs... PROGRAMS (CONTINUED) PERMITS REGULATION Acid Rain Phase II Implementation § 72.71 Acceptance of State Acid... State Acid Rain program meeting the requirements of §§ 72.72 and 72.73. (b) The Administrator...

  7. 40 CFR 72.71 - Acceptance of State Acid Rain programs-general.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Acceptance of State Acid Rain programs... PROGRAMS (CONTINUED) PERMITS REGULATION Acid Rain Phase II Implementation § 72.71 Acceptance of State Acid... State Acid Rain program meeting the requirements of §§ 72.72 and 72.73. (b) The Administrator...

  8. A meteorological potential forecast model for acid rain in Fujian Province, China.

    PubMed

    Cai, Yi Yong; Lin, Chang Cheng; Liu, Jing Xiong; Wu, De Hui; Lian, Dong Ying; Chen, Bin Bin

    2010-05-01

    Based on the acid rain and concurrent meteorological observational data during the past 10 years in Fujian Province, China, the dependence of distribution characteristics of acid rain on season, rain rate, weather pattern and dominant airflow in four regions of Fujian Province is analyzed. On the annual average, the acid rain frequency is the highest (above 40%) in the southern and mid-eastern regions, and the lowest (16.2%) in the western region. The acid rain occurs most frequently in spring and winter, and least frequent in summer. The acid rain frequency in general increases with the increase of precipitation. It also depend on the direction of dominant airflows at 850 hPa. In the mid-eastern region, more than 40% acid rains appear when the dominant wind directions are NW, W, SW, S and SE. In the southern region, high acid rain occurrence happens when the dominant wind directions are NW, W, SW and S. In the northern region, 41.8% acid rains occur when the southwesterly is pronounced. In the western region, the southwesterly is associated with a 17% acid rain rate. The examination of meteorological sounding conditions over Fuzhou, Xiamen and Shaowu cities shows that the acid rain frequency increases with increased inversion thickness. Based on the results above, a meteorological potential forecast model for acid rain is established and tested in 2007. The result is encouraging. The model provides an objective basis for the development of acid rain forecasting operation in the province.

  9. Efficient inhibition of heavy metal release from mine tailings against acid rain exposure by triethylenetetramine intercalated montmorillonite (TETA-Mt).

    PubMed

    Gong, Beini; Wu, Pingxiao; Huang, Zhujian; Li, Yuanyuan; Yang, Shanshan; Dang, Zhi; Ruan, Bo; Kang, Chunxi

    2016-11-15

    The potential application of triethylenetetramine intercalated montmorillonite (TETA-Mt) in mine tailings treatment and AMD (acid mine drainage) remediation was investigated with batch experiments. The structural and morphological characteristics of TETA-Mt were analyzed with XRD, FTIR, DTG-TG and SEM. The inhibition efficiencies of TETA-Mt against heavy metal release from mine tailings when exposed to acid rain leaching was examined and compared with that of triethylenetetramine (TETA) and Mt. Results showed that the overall inhibition by TETA-Mt surpassed that by TETA or Mt for various heavy metal ions over an acid rain pH range of 3-5.6 and a temperature range of 25-40°C. When mine tailings were exposed to acid rain of pH 4.8 (the average rain pH of the mining site where the mine tailings were from), TETA-Mt achieved an inhibition efficiency of over 90% for Cu(2+), Zn(2+), Cd(2+) and Mn(2+) release, and 70% for Pb(2+) at 25°C. It was shown that TETA-Mt has a strong buffering capacity. Moreover, TETA-Mt was able to adsorb heavy metal ions and the adsorption process was fast, suggesting that coordination was mainly responsible. These results showed the potential of TETA-Mt in AMD mitigation, especially in acid rain affected mining area.

  10. Acid Rain Education and Its Implications for Curricular Development: A Teacher Survey.

    ERIC Educational Resources Information Center

    Barrow, Lloyd H.; Germann, Paul

    1987-01-01

    Describes a survey which was designed to obtain information on acid rain education. Reviews results pertaining to instructional time, instructional topics, use of labs from a common resource guide, and preference of materials related to acid rain education. (ML)

  11. A Demonstration of Acid Rain and Lake Acidification: Wet Deposition of Sulfur Dioxide.

    ERIC Educational Resources Information Center

    Goss, Lisa M.

    2003-01-01

    Introduces a science demonstration on the dissolution of sulfuric oxide emphasizing the concept of acid rain which is an environmental problem. Demonstrates the acidification from acid rain on two lake environments, limestone and granite. Includes safety information. (YDS)

  12. Learning About Acid Rain: A Teacher's Guide for Grades 6 through 8

    EPA Pesticide Factsheets

    Find on this page a link to the Acid Rain Teacher's Guide for Students Grades 6-8. This guide contains information, class discussions and experiments teachers can use to teach students about acid rain.

  13. The erosion of carbonate stone by acid rain: Laboratory and field investigations

    USGS Publications Warehouse

    Baedecker, P.A.; Reddy, M.M.

    1993-01-01

    One of the goals of research on the effects of acidic deposition on carbonate stone surfaces is to define the incremental impact of acidic deposition relative to natural weathering processes on the rate of carbonate stone erosion. If rain that impacts carbonate stone surfaces is resident on the surface long enough to approach chemical equilibrium, the incremental effect of hydrogen ion is expected to be small (i.e., 6% for a rain of pH 4.0). Under nonequilibrium (i.e., high flow rate) conditions, kinetic considerations suggest that the incremental effect of hydrogen ion deposition could be quite significant. Field run-off experiments involving the chemical analysis of rain collected from inclined stone slabs have been used to evaluate stone dissolution processes under ambient conditions of wet and dry deposition of acidic species. The stoichiometry of the reaction of stone with hydrogen ion is difficult to define from the field data due to scatter in the data attributed to hydrodynamic effects. Laboratory run-off experiments show that the stoichiometry is best defined by a reaction with H+ in which CO2 is released from the system. The baseline effect caused by water in equilibrium with atmospheric CO2 is identical in the field and in laboratory simulation. The experiments show that the solutions are close enough to equilibrium for the incremental effect of hydrogen ion to be minor (i.e., 24% for marble for a rain of pH 4.0) relative to dissolution due to water and carbonic acid reactions. Stone erosion rates based on physical measurement are approximately double the recession rates that are due to dissolution (estimated from the observed calcium content of the run-off solutions). The difference may reflect the loss of granular material not included in recession estimates based on the run-off data. Neither the field nor the laboratory run-off experiments indicate a pH dependence for the grain-removal process.

  14. The urban perspectives of acid rain. Workshop summary

    SciTech Connect

    Tonn, B.E.

    1993-06-04

    This report documents discussions held during a workshop an Urban Perspective of Acid Rain. The workshop was sponsored by the Office of the Director, National Acid Precipitation Assessment Program (NAPAP). NAPAP anticipates giving increased emphasis to the benefits in urban areas of emissions reductions. The goal of this informal, exploratory workshop was to serve as a first step towards identifying pollutant monitoring, and research and assessment needs to help answer, from an urban perspective, the two key questions posed to NAPAP by Congress: (1) what are the costs, benefits, and effectiveness of the acid rain control program, and (2) what reductions in deposition, rates are needed in order to prevent adverse effects? The workshop addressed research activities needed to respond to these questions. The discussions focused. sequentially, on data needs, data and model availability, and data and modeling gaps. The discussions concentrated on four areas of effects: human health, materials, urban forests, and visibility.

  15. Adirondack tourism: perceived consequences of acid rain

    SciTech Connect

    Metz, W.C.

    1984-03-01

    This report seeks to place in perspective the perceived effects of acid precipitation on the tourist industry in the Adirondacks. The 9375-square mile park is host to almost nine million tourists annually, not including seasonal residents. Since the park was established almost 100 years ago, there have been many changes in tourist characteristics, available recreational facilities, kinds of activities, accessibility of the area, and land use and resource management policies. The tourist industry has been influenced by both controllable and uncontrollable factors. At present the overwhelming majority of recreational opportunities and natural resources important to the Adirondack tourist industry are relatively unaffected by acid precipitation. Fishing, a significant component of the tourist industry, is the most vulnerable, but any presumed adverse economic effect has to be weighed against the location of the impacted waters, total Adirondack fishing habitat, substitution available, habitat usage, fisherman characteristics, resource management, and the declining importance of fishing as an Adirondack recreational attraction. Concern is expressed as to whether present minimal acidification impacts are the precursor of major future impacts on Adirondack terrestrial and aquatic environments, and ultimately tourism. Tourism in the Adirondacks is increasing, while many other regional employment sectors are declining. It is becoming a more stable multiseason industry. Its future growth and character will be affected by government, private organization, business community, and resident controversies regarding land use and resource management attitudes, policies, budgets, and regulations. The acid precipitation issue is only one of many related controversies. 65 references, 2 figures.

  16. [Combined effects of copper and simulated acid rain on copper accumulation, growth, and antioxidant enzyme activities of Rumex acetosa].

    PubMed

    He, Shan-Ying; Gao, Yong-Jie; Shentu, Jia-Li; Chen, Kun-Bai

    2011-02-01

    A pot experiment was conducted to study the combined effects of Cu (0-1500 mg x kg(-1)) and simulated acid rain (pH 2.5-5.6) on the copper accumulation, growth, and antioxidant enzyme activities of Rumex acetosa. With the increasing concentration of soil Cu, the Cu accumulation in R. acetosa increased, being higher in root than in stem and leaf. The exposure to low pH acid rain promoted the Cu uptake by R. acetosa. With the increase of soil Cu concentration and/or of acid rain acidity, the biomass of R. acetosa decreased, leaf and root MDA contents increased and had good correlation with soil Cu concentration, and the SOD and POD activities in leaf and root displayed a decreasing trend after an initial increase. This study showed that R. acetosa had a strong adaptive ability to Cu and acid rain stress, exhibiting a high application potential in the remediation of Cu-contaminated soil in acid rain areas.

  17. Acid rain study: Do it again

    NASA Astrophysics Data System (ADS)

    Maggs, William Ward

    James Mahoney, newly appointed head of the Reagan administration's National Acid Precipitation Assessment Program (NAPAP), got a writing assignment last week from Rep. James Scheuer (D-N.Y.) , a subcommittee chairman of the House Committee on Science, Space, and Technology (SST).At a hearing on April 27, 1988, Mahoney agreed to Scheuer's request that he rewrite by Labor Day the executive summary o f an interim report o n NAPAP's progress that was submitted to Congress during September 1987. The summary, written by Mahoney's predecessor, J. Laurence Kulp, was immediately criticized by scientists, legislators, and environmental groups as a distortion of facts and a whitewash of the scientific conclusions of the interim report. Kulp resigned within a week of the summary's release.

  18. Spatial characterization of acid rain stress in Canadian Shield lakes

    NASA Technical Reports Server (NTRS)

    Tanis, Fred J.

    1986-01-01

    The acidification of lake waters from airborne pollutants is of continental proportions both in North America and Europe. A major concern of the acid rain problem is the cumulative ecosystem damage to lakes and forest. The number of lakes affected in northeastern United States and on the Canadian Shield is though to be enormous. The principle objective is to examine how seasonal changes in lake water transparency are related to annual acidic load. Further, the relationship between variations in lake acidification and ecophysical units is being examined. Finally, the utility of Thematic Mapper (TM) based observations to measure seasonal changes in the optical transparency in acid lakes is being investigated.

  19. Spatial characterization of acid rain stress in Canadian Shield lakes

    NASA Technical Reports Server (NTRS)

    Tanis, Fred J.

    1986-01-01

    A major concern of the acid rain problem is the cumulative ecosystem damage to lakes and forests. The number of lakes affected in northeastern United States and on the Canadian Shield is thought to be enormous. Seasonal changes in lake transparency are examined relative to annual acidic load. The relationship between variations in lake acidification and ecophysical units is being examined. Finally, the utility of Thematic Mapper (TM) based observations is being used to measure seasonal changes in the optical transparency in acid lakes.

  20. Evaluation of the Acid Rain approach to monitor certification

    SciTech Connect

    Bloomer, B.J.

    1995-12-31

    November 15, 1990 saw the passage of the Clean Air Act Amendments of 1990. Within this law are the requirements for all electric utility units greater than 25 megawatts of generated electrical capacity to monitor SO{sub 2}, NO{sub x}, CO{sub 2}. This paper summarizes the Acid Rain Program`s approach to Continuous Emissions Monitoring Systems (CEMS) certification testing requirements and their purpose in this market based pollution control program, created as a result of Title IV of the Clean Air Act Amendments of 1990. This paper presents a brief introduction to the theory behind the required tests. The author then presents summary evaluation of the certification test results for CEMS installed at the Phase 1 sources affected by the Acid Rain Program.

  1. Gas dilution system results and application to acid rain utilities

    SciTech Connect

    Jolley-Souders, K.; Geib, R.; Dunn, C.

    1997-12-31

    In 1997, the United States EPA will remove restrictions preventing acid rain utilities from using gas dilution systems for calibration or linearity studies for continuous emissions monitoring, Test Method 205 in 40CFR51 requires that a gas dilution system must produce calibration gases whose measured values are within {+-}2% of predicted values. This paper presents the evaluation of the Environics/CalMat 2020 Dilution System for use in calibration studies. Internal studies show that concentrations generated by this unit are within {+-}0.5% of predicted values. Studies are being conducted by several acid rain utilities to evaluate the Environics/CalMat system using single minor component calibration standards. In addition, an internally generated study is being performed to demonstrate the system`s accuracy using a multi-component gas mixture. Data from these tests will be presented in the final version of the paper.

  2. Interactions of gaseous-pollutant and acid-rain effects

    SciTech Connect

    Shriner, D.S.

    1983-01-01

    This research addresses the significance of individual and combined effects of gaseous pollutants and acid rain on plant growth and development. It is specifically structured to determine the importance of pollutant interactions at concentrations, combinations and exposure frequencies typical of the eastern regional environment. Laboratory, greenhouse, and field studies are designed to establish pollutant-concentration thresholds for damage from SO/sub 2/, O/sub 3/, NO/sub x/, and acid rain. Research to date has determined visible-injury thresholds and growth-and-yield thresholds for a variety of cultivars of bean, wheat, radish, tomato, and loblolly pine. The thresholds vary within cultivars of a species and between species.

  3. Effects of silicon on Oryza sativa L. seedling roots under simulated acid rain stress.

    PubMed

    Ju, Shuming; Yin, Ningning; Wang, Liping; Zhang, Cuiying; Wang, Yukun

    2017-01-01

    Silicon (Si) has an important function in reducing the damage of environmental stress on plants. Acid rain is a serious abiotic stress factor, and Si can alleviate the stress induced by acid rain on plants. Based on these assumptions, we investigated the effects of silicon on the growth, root phenotype, mineral element contents, hydrogen peroxide (H2O2) and antioxidative enzymes of rice (Oryza sativa L.) seedling roots under simulated acid rain (SAR) stress. The results showed that the combined or single effects of Si and/or SAR on rice roots depend on the concentration of Si and the pH of the SAR. The combined or single effects of a low or moderate concentration of Si (1.0 or 2.0 mM) and light SAR (pH 4.0) enhanced the growth of rice roots, and the combined effects were stronger than those of the single treatment. A high concentration of Si (4.0 mM) or severe SAR (pH 2.0) exerted deleterious effects. The incorporation of Si (1.0, 2.0 or 4.0 mM) into SAR with pH 3.0 or 2.0 promoted the rice root growth, decreased the H2O2 content, increased the Si concentration and the superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and ascorbate peroxidase (APX) activities, maintained the balance of mineral element (K, Ca, Mg, Fe, Zn, and Cu) concentrations in the roots of rice seedlings compared with SAR alone. The alleviatory effects observed with a moderate concentration of Si (2.0 mM) were better than the effects obtained with a low or high concentration of Si (1.0 or 4.0 mM). The observed effects were due to disruptions in the absorption and utilization of mineral nutrients and impacts on the activity of antioxidant enzymes in roots, and this conclusion suggests that the degree of rice root damage caused by acid rain might be attributed to not only acid rain but also the level of Si in the soil.

  4. Effects of silicon on Oryza sativa L. seedling roots under simulated acid rain stress

    PubMed Central

    Wang, Liping; Zhang, Cuiying; Wang, Yukun

    2017-01-01

    Silicon (Si) has an important function in reducing the damage of environmental stress on plants. Acid rain is a serious abiotic stress factor, and Si can alleviate the stress induced by acid rain on plants. Based on these assumptions, we investigated the effects of silicon on the growth, root phenotype, mineral element contents, hydrogen peroxide (H2O2) and antioxidative enzymes of rice (Oryza sativa L.) seedling roots under simulated acid rain (SAR) stress. The results showed that the combined or single effects of Si and/or SAR on rice roots depend on the concentration of Si and the pH of the SAR. The combined or single effects of a low or moderate concentration of Si (1.0 or 2.0 mM) and light SAR (pH 4.0) enhanced the growth of rice roots, and the combined effects were stronger than those of the single treatment. A high concentration of Si (4.0 mM) or severe SAR (pH 2.0) exerted deleterious effects. The incorporation of Si (1.0, 2.0 or 4.0 mM) into SAR with pH 3.0 or 2.0 promoted the rice root growth, decreased the H2O2 content, increased the Si concentration and the superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and ascorbate peroxidase (APX) activities, maintained the balance of mineral element (K, Ca, Mg, Fe, Zn, and Cu) concentrations in the roots of rice seedlings compared with SAR alone. The alleviatory effects observed with a moderate concentration of Si (2.0 mM) were better than the effects obtained with a low or high concentration of Si (1.0 or 4.0 mM). The observed effects were due to disruptions in the absorption and utilization of mineral nutrients and impacts on the activity of antioxidant enzymes in roots, and this conclusion suggests that the degree of rice root damage caused by acid rain might be attributed to not only acid rain but also the level of Si in the soil. PMID:28291806

  5. Performance of Vicia faba plants in relation to simulated acid rain and/or endosulphan treatment

    SciTech Connect

    Singh, N.; Yunus, M.; Singh, S.N.; Ahmad, K.J. )

    1992-02-01

    The increasing human population in India is necessitating the optimum use of cultivable land for increased food production. Eradication and control of pests and pathogens is an essential component of any strategy for increased agricultural production. In this context, the use of pesticides to control the incidence of disease in crops becomes inevitable. Most of the pesticides used for foliar spraying invariably contain surfactants in their formulation, which not only increase the surface wettability but also enhance permeability of the cuticle for more cation infusion/effusion and hence they may make the leaf more susceptible to direct effects of acid rain. To evaluate the validity of this assumption, an experiment using endosulphan, the most commonly used insecticide in India, and acid rain of different pH was conducted on Vicia faba.

  6. Experimental investigation of influence of acid rain on leaching and hydraulic characteristics of cement-based solidified/stabilized lead contaminated clay.

    PubMed

    Du, Yan-Jun; Jiang, Ning-Jun; Shen, Shui-Long; Jin, Fei

    2012-07-30

    Remediation of contaminated lands in China urban areas is of great concern. Degradation of construction facilities caused by acid rain is a serious environmental pollution issue in China. This paper presents an investigation of the effects of acid rain on leaching and hydraulic properties of cement-based solidified/stabilized lead contaminated soil. Laboratory tests including infiltration test and soaking test are conducted. It is found that the soil hydraulic conductivity decreases with increase in the pore volume of flow of permeant liquids (acid rain and distilled water). The decreasing rate in the case of the acid rain is lower than that in the case of the distilled water. The soaking test results show that pH and the presence of sulfate ions of acid rain have considerable influence on the leached concentrations and leaching rate of calcium.

  7. Streams in Catskill Mountains still susceptible to acid rain

    NASA Astrophysics Data System (ADS)

    Burns, Douglas A.; Lawrence, Gregory B.; Murdoch, Peter S.

    Precipitation in North America has become less acidic over the past 2 decades because of reduced power plant emissions and compliance with the Clean Air Act Amendments [Sirois, 19937rsqb;. The 1990 Clean Air Act Amendments were developed to reduce the acidity of sensitive surface waters, which are primarily in upland forested environments, where acidified waters and associated high aluminum concentrations are toxic to many species of aquatic flora and fauna [Schindler et al., 1989]. Our studies show that in spite of less acidic precipitation, the buffering capacity of streams in upland forests of the Catskill Mountains in southeastern New York has not increased in recent years. These data suggest that long-term leaching by acid rain has lowered exchangeable calcium ion concentrations in the soil in upland areas, where the underlying, slow-weathering bedrock provides an inadequate supply of cations to neutralize acidity.

  8. Responses of tropical legumes from the Brazilian Atlantic Rainforest to simulated acid rain.

    PubMed

    Andrade, Guilherme C; Silva, Luzimar C

    2016-12-08

    We investigated the morphological and anatomical effects of simulated acid rain on leaves of two species native to the Brazilian Atlantic Rainforest: Paubrasilia echinata and Libidibia ferrea var. leiostachya. Saplings were subjected to acid rain in a simulation chamber during 10 days for 15 min daily, using H2SO4 solution pH 3.0 and, in the control, deionized water. At the end of the experiment, fragments from young and expanding leaves were anatomically analyzed. Although L. ferrea var. leiostachya leaves are more hydrophobic, rain droplets remained in contact with them for a longer time, as in the hydrophilic P. echinata leaves, droplets coalesce and rapidly run off. Visual symptomatology consisted in interveinal and marginal necrotic dots. Microscopic damage found included epicuticular wax flaking, turgor loss and epidermal cell shape alteration, hypertrophy of parenchymatous cells, and epidermal and mesophyll cell collapse. Formation of a wound tissue was observed in P. echinata, and it isolated the necrosis to the adaxial leaf surface. Acid rain increased thickness of all leaf tissues except spongy parenchyma in young leaves of L. ferrea var. leiostachya, and such thickness was maintained throughout leaf expansion. To our knowledge, this is the first report of acidity causing increase in leaf tissue thickness. This could represent the beginning of cell hypertrophy, which was seen in visually affected leaf regions. Paubrasilia echinata was more sensitive, showing earlier symptoms, but the anatomical damage in L. ferrea var. leiostachya was more severe, probably due to the higher time of contact with acid solution in this species.

  9. Spatial characterization of acid rain stress in Canadian Shield Lakes

    NASA Technical Reports Server (NTRS)

    Tanis, Fred J.

    1987-01-01

    The acidification of lake waters from airborne pollution is of continental proportions both in North America and Europe. A major concern of the acid rain problem is the cumulative ecosystem damage to lakes and forest. The number of lakes affected in northeastern U.S. and on the Canadian Shield is though to be enormous. How seasonal changes in lake transparency are related to annual acidic load was examined. The relationship between variations in lake acidification and ecophysical units was also examined. The utility of Thematic Mapper based observations to measure seasonal changes in the optical transparency in acid lakes was investigated. The potential for this optical response is related to a number of local ecophysical factors with bedrock geology being, perhaps, the most important. Other factors include sulfate deposition, vegetative cover, and terrain drainage/relief. The area of southern Ontario contains a wide variety of geologies from the most acid rain sensitive granite quartzite types to the least sensitive limestone dolomite sediments. Annual sulfate deposition ranges from 1.0 to 4.0 grams/sq m.

  10. Characterizing the release of different composition of dissolved organic matter in soil under acid rain leaching using three-dimensional excitation-emission matrix spectroscopy.

    PubMed

    Liu, Li; Song, Cunyi; Yan, Zengguang; Li, Fasheng

    2009-09-01

    Although excitation-emission matrix spectroscopy (EEMS) has been widely used to characterize dissolved organic matter (DOM), there has no report that EEMS has been used to study the effects of acid rain on DOM and its composition in soil. In this work, we employed three-dimensional EEMS to characterize the compositions of DOM leached by simulated acid rain from red soil. The red soil was subjected to leaching of simulated acid rain of different acidity, and the leached DOM presented five main peaks in its EEMS: peak-A, related to humic acid-like (HA-like) material, at Ex/Em of 310-330/395-420nm; peak-B, related to UV fulvic acid-like (FA-like) material, at Ex/Em of 230-280/400-435nm; peak-C and peak-D, both related to microbial byproduct-like material, at Ex/Em of 250-280/335-355nm and 260-280/290-320nm, respectively; and peak-E, related to simple aromatic proteins, at Ex/Em of 210-240/290-340nm. EEMS analysis results indicated that most DOM could be lost from red soil in the early phase of acid rain leaching. In addition to the effects of the pH of acid rain, the loss of DOM also depended on the properties of its compositions and the solubility of their complexes with aluminum. HA-like and microbial byproduct-like materials could be more easily released from red soil by acid rain at both higher pH (4.5 and 5.6) and lower pH (2.5 and 3) than that at middle pH (3.5). On the contrary, FA-like material lost in a similar manner under the action of different acid rains with pH ranging from 2.5 to 5.6.

  11. [THE EFFECT OF ACID RAIN ON ULTRASTRUCTURE AND FUNCTIONAL PARAMETERS OF PHOTOSYNTHETIC APPARATUS OF PEA LEAVES].

    PubMed

    Polishchuk, A V; Vodka, M V; Belyavskaya, N A; Khomochkin, A P; Zolotareva, E K

    2016-01-01

    The effects of simulated acid rain (SAR) on the ultrastructure and functional parameters of the photosynthetic apparatus were studied using 14-day-old pea leaves as test system. Pea plants were sprayed with an aqueous solution containing NaNO₃(0.2 mM) and Na₂SO₄(0.2 mM) (pH 5.6, a control variant), or with the same solution, which was acidified to pH 2.5 (acid variant). Functional characteristics were determined by chlorophyll fluorescence analysis. Acid rain application caused reduction in the efficiency of the photosynthetic electron transport by 25%, which was accompanied by an increase by 85% in the quantum yield of thermal dissipation of excess light quanta. Ultrastructural changes in chloroplast were registered by transmission electron microscopy (TEM) after two days of the SAR-treatment of pea leaves. In this case, the changes in the structure of grana, heterogeneity of thylakoids packaging in granum, namely, the increase of intra-thylakoid gaps and thickness of granal thylakoids compared to the control were found. The migration of protein complexes in thylakoid membranes of chloroplasts isolated from leaves treated with SAR was suppressed. It was shown also that carbonic anhydrase activity was inhibited in chloroplast preparations isolated from SAR-treated pea leaves. We proposed a hypothesis on the possible inactivation of thylakoid carbonic anhydrase under SAR and its involvement in the inhibition of photochemical activity of chloroplasts. The data obtained allows to suggest that acid rains negatively affect the photosynthetic apparatus disrupting the membrane system of chloroplast.

  12. Alkalization of yellow sand and its long-term effects on acid rain in East Asia: Observed Evidence and Simulation

    NASA Astrophysics Data System (ADS)

    Wang, Z.; Uno, I.; Akimoto, H.

    2001-05-01

    Acid rain has been one of the serious environmental problems in East Asia for the rapid industrialization in the last two decades. The contour line of pH value less than 5 has come up to the Yellow River region (35 deg N) from the southern China bounded by the Yangtze River (25 deg N) during these ten years. The objective of EANET ( Acid Deposition Moniroring Network in East Asia) is to create a common understanding of the state of the acid deposition problems in East Asia. There are 38 monitoring sites for wet deposition monitoring and data was collected since January 1999. The analysis of datasets in 1999 shows that aerosol has alkalization effects on pH of rain, especially in spring. An Air Quality Prediction Modeling System (AQPMS) was used to investigate the neutralization of acid rain by the yellow-sand in East Asia. The AQPMS includes all the major processes such as emission, advection, diffusion, chemistry, dry deposition, wet deposition and micro-physical processes. A new deflation module for the dust uptake is designed to estimate the dust loading (Wang et. al.,2000). The gas-phase chemical reaction scheme is a slightly modified version of the CBM-IV. Changes in trace species concentrations due to chemical reactions of soluble and reactive gases in in-cloud and below-cloud droplets are computed using a box aqueous chemical model. Numerical simulation was performed for two cases, that is, with and without the neutralization effects of Kosa in 1999. The predicted pH values and sulfate- and nitrate-ion levels of precipitation, together with the surface concentrations of gaseous pollutants, were compared with measured datasets of EANET and a reasonable agreement was obtained. The simulation results of 1999 exhibited a strong neutralization of the precipitation by the yellow-sand in the spring. The aerosol has alkalization effects on pH of rain, which reduces the H+ of rain.

  13. [Seasonality and contribution to acid rain of the carbon abundance in rainwater].

    PubMed

    Xu, Tao; Song, Zhi-guang; Liu, Jun-feng; Wang, Cui-ping

    2008-02-01

    This paper reports the results from a study of the carbon abundance in rainwater of Guangzhou city, China. The determination of TOC, DOC, POC and PEC helps to study the seasonality of carbon abundance and its contribution to the acid rain. The results display the fact that the average contents of TOC, DOC, POC and PEC are 7.10 mg/L, 3.58 mg/L, 3.60 mg/L and 0.72 mg/L, respectively. These results confirm the deep effect of the organic pollutant to the rain. The seasonality exists in the carbon abundance of rainwater. The contents of TOC and DOC are up to the maximum in spring and the minimum in summer; the contribution of POC to TOC in summer is obviously higher than that in other seasons; and the relative content of POC is clearly higher in dry season than that in wet season. The seasonality reflects the more emission of the total pollutant in spring and the solid particle pollutant in summer than those in other seasons. Moreover, the emission of the organic pollutant from the mobile vehicles is more obvious in dry season than that in wet season. The contents of TOC and DOC have the negative correlation to the pH values, which confirms the contribution effect of the organic pollutant, such as vehicle emission, to the acid rain.

  14. [Complex effects of simulated acid rain and Cu on the physiological characteristics of Paulownia fortunei and its detoxification mechanism].

    PubMed

    Wang, Jiang; Zhang, Chong-Bang; Ke, Shi-Sheng; Qian, Bao-Ying

    2010-03-01

    A pot experiment was conducted to study the effects of simulated acid rain (pH 4.0, 5.0) and Cu (0-200 mg x kg(-1)) on the physiological characteristics of Paulownia fortunei and its detoxification mechanism. With no Cu addition, the leaf chlorophyll, carotenoid, O2 division by, H2O2, and MDA contents of P. fortunei had no significant differences between the two acid rain treatments. However, with the addition of 100 and 200 mg Cu x kg(-1), the chlorophyll and carotenoid contents of treatment pH 4.0 were lower, while the O2 divided by, H2O2 and MDA contents were higher thanthose of treatment pH 5.0. The chlorophyll a/b ratio of treatments Cu was higher than that of the control. The leaf Cu content decreased obviously with the increasing acidity of stimulated acid rain, but the root Cu content was in reverse. With increasing Cu addition, both the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) and the total contents of phytochelatins (PCs) and glutathione (GSH) in treatment pH 5.0 increased, while the activities of SOD, POD, CAT and APX in treatment pH 4.0 decreased after an initial increase, and the total contents of glutathione (GSH) decreased greatly in treatment 200 mg Cu x kg(-1). All of these demonstrated that the oxidative stress of high Cu concentration to P. fortunei was aggravated by stimulated acid rain.

  15. Acid Rain: A Selective Bibliography. Second Edition. Bibliography Series Twenty-One.

    ERIC Educational Resources Information Center

    O'Neill, Gertrudis, Comp.

    Acid rain is a term for rain, snow, or other precipitation produced from water vapor in the air reacting with emissions from automobiles, factories, power plants, and other oil and coal burning sources. When these chemical compounds, composed of sulfur oxide and nitrogen oxide, react with water vapor, the result is sulfuric acid and nitric acid.…

  16. Acid rain and our nation`s capital: A guide to effects on buildings and monuments

    SciTech Connect

    McGee, E.

    1997-03-01

    This booklet focuses on acid rain and its impact on our Nation`s capital. This booklet will define acid rain, explain what effects it has on marble and limestone buildings, and show, on a walking tour, some of the places in our Nation`s capital where you can see the impact of acid precipitation.

  17. 78 FR 64496 - Acid Rain Program: Notice of Annual Adjustment Factors for Excess Emissions Penalty

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-29

    ... AGENCY Acid Rain Program: Notice of Annual Adjustment Factors for Excess Emissions Penalty AGENCY.... SUMMARY: The Acid Rain Program under title IV of the Clean Air Act provides for automatic excess emissions penalties in dollars per ton of excess emissions for sources that do not meet their annual Acid...

  18. 76 FR 71559 - Acid Rain Program: Notice of Annual Adjustment Factors for Excess Emissions Penalty

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-18

    ... AGENCY Acid Rain Program: Notice of Annual Adjustment Factors for Excess Emissions Penalty AGENCY.... SUMMARY: The Acid Rain Program under title IV of the Clean Air Act provides for automatic excess emissions penalties in dollars per ton of excess emissions for sources that do not meet their annual Acid...

  19. [Yesterday, today, tomorrow. A retrospective look at the acid rain problem].

    PubMed

    Buijsman, Ed

    2008-01-01

    Last century, at the end of the seventies, Europe was startled by a serious environmental problem: acid rain. Acid rain was held responsible for the decline of fishes in Scandinavian lakes. Later, it was suggested that acid rain could lead to forest dieback over vast areas of Europe. Forests in the Netherlands could be at great risk, as well. It was clear to everyone what it was all about, for 'rain' means water falling from the atmosphere and the meaning of 'acid' was evident, too. Acid rain caused much commotion in the eighties but, since then, it has faded into the background. Why is it, that there is so little attention paid to acid rain these days? Maybe the acid rain problem was a hype; with an exaggerated reaction to a problem that was, in fact, insignificant. This article aims to reconstruct the history of one of the most prominent environmental problems of the twentieth century. The article describes the origin of the acid rain problem in the 1960s and describes the scientific research that was carried out to develop a better understanding of the problem from an atmospheric chemical point of view. Subsequently, it treats the rise of public awareness in the seventies. The article subsequently focuses on the situation in the Netherlands. The initial research into forest health showed alarming results. This led to widespread concern within The Netherlands, which, once more, urged the government to come into action. Some measures to reduce air-polluting emissions were already taken in the early 1980s. However, these were meant, mainly, to improve local air quality. As the eighties progressed, acid rain provided an additional argument for reducing air pollution. This article presents the consequences of the emission reductions for the acidity of acid rain, and it discusses--in brief--the acid rain problem in light of current scientific knowledge. Finally, it answers the question of why forests did not die.

  20. [Effects of exogenous nitric oxide on physiological characteristics of longan (Dimocarpus longana) seedlings under acid rain stress].

    PubMed

    Liu, Jian-fu; Wang, Ming-yuan; Yang, Chen; Zhu, Ai-jun

    2013-08-01

    This paper studied the effects of exogenous nitric oxide donor sodium nitroprusside (SNP) on the chlorophyll content, antioxidant enzyme activities, and osmotic regulation substances of longan (Dimocarpus longana 'Fuyan') seedlings under acid rain (pH 3.0) stress. Under the acid rain stress, the seedling leaf superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities and chlorophyll, soluble protein and soluble sugar contents decreased obviously, while the leaf malondialdedyde content had a remarkable increase, suggesting the toxic effect of the acid rain on the seedlings. Exogenous nitric oxide had dual nature on the physiological characteristics of longan seedlings under acid rain stress. Applying 0.1-0.5 mmol x L(-1) of SNP improved the SOD, POD and CAT activities and the chlorophyll, soluble protein and soluble sugar contents significantly, and decreased the malondialdedyde content. Low concentrations SNP reduced the oxidative damage caused by the acid rain stress, and 0.5 mmol x L(-1) of SNP had the best effect. Under the application of 0.5 mmol x L(-1) of SNP, the total chlorophyll, soluble protein, and soluble sugar contents and the SOD, POD and CAT activities increased by 76.0%, 107.0%, 216.1%, 150. 0%, 350.9% and 97.1%, respectively, and the malondialdedyde content decreased by 46.4%. It was suggested that low concentration (0.1-0.5 mmol x L(-1)) SNP could alleviate the toxic effect of acid rain stress on longan seedlings via activating the leaf antioxidant enzyme activities and reducing oxidative stress, while high concentration SNP (1.0 mmol x L(-1)) lowered the mitigation effect.

  1. [Effects of simulating acid rain on photosynthesis and chlorophyll fluorescence parameters of Quercus glauca Quercus glauca].

    PubMed

    Wang, Sai; Yi, Li-Ta; Yu, Shu-Quan; Zhang, Chao; Shi, Jing-Jing

    2014-08-01

    At three levels of simulated acid rainfall intensities with pH values of 2.5 (severe), 40 (medium) and 5.6 (light) respectively, the responses of chlorophyll fluorescence and photosynthetic parameters of Quercus glauca seedlings were studied in three acid rainfall treatments, i. e. only the aboveground of seedlings exposed to acid rain (T1), both of the seedlings and soil exposed to acid rain (T2), only the soil exposed to acid rain (T3) compared with blank control (CK). Under the severe acid rainfall, T1 significantly inhibited chlorophyll synthesis, and thus reduced the primary photochemical efficiency of PS II ( F(v)/F(m)), potential activity of PS II (F(v)/F(o)) , apparent quantum (Y), net photosynthetic rate (P(n)), and transpiration rate (T(r)), but increased the light compensation point (LCP) and dark respiration rate (R(d)) of Q. glauca seedlings. T2 inhibited, but T3 played a little enhancement on the aforementioned parameters of Q. glauca seedlings. Under the conditions of medium and light acid rainfall intensities, the above parameters in the three treatments were higher than that of CK, except with lower R(d). The chlorophyll fluorescence and photosynthetic parameters showed a similar tendency in the three treatments, i. e. T2>T3 >T1. It indicated that T1 had the strongest inhibition on seedlings in condition of the severe acid rainfall, while T2 had the most dramatic facilitating effect on seedlings under the medium and light acid rainfall. Intensity of acid rainfall had significant influences on SPAD, F(v)/F(m), F(v)/F(o), Y, P(n), T(r), and maximum photosynthetic rate (A(max)), whereas treatments of acid rainfall affected SPAD, F(v)/F(m), Y, P(n), T(r), A(max) and light saturation point (LSP). The interaction of acid rainfall intensities and treatments played significant effects on SPAD, F(v)/F(m), Y, P(n) and A(max).

  2. Leaching behavior of heavy metals and transformation of their speciation in polluted soil receiving simulated acid rain.

    PubMed

    Zheng, Shun-an; Zheng, Xiangqun; Chen, Chun

    2012-01-01

    Heavy metals that leach from contaminated soils under acid rain are of increasing concern. In this study, simulated acid rain (SAR) was pumped through columns of artificially contaminated purple soil. Column leaching tests and sequential extraction were conducted for the heavy metals Cu, Pb, Cd, and Zn to determine the extent of their leaching as well as to examine the transformation of their speciation in the artificially contaminated soil columns. Results showed that the maximum leachate concentrations of Cu, Pb, Cd, and Zn were less than those specified in the Chinese Quality Standards for Groundwater (Grade IV), thereby suggesting that the heavy metals that leached from the polluted purple soil receiving acid rain may not pose as risks to water quality. Most of the Pb and Cd leachate concentrations were below their detection limits. By contrast, higher Cu and Zn leachate concentrations were found because they were released by the soil in larger amounts as compared with those of Pb and Cd. The differences in the Cu and Zn leachate concentrations between the controls (SAR at pH 5.6) and the treatments (SAR at pH 3.0 and 4.5) were significant. Similar trends were observed in the total leached amounts of Cu and Zn. The proportions of Cu, Pb, Cd, and Zn in the EXC and OX fractions were generally increased after the leaching experiment at three pH levels, whereas those of the RES, OM, and CAR fractions were slightly decreased. Acid rain favors the leaching of heavy metals from the contaminated purple soil and makes the heavy metal fractions become more labile. Moreover, a pH decrease from 5.6 to 3.0 significantly enhanced such effects.

  3. Leaching Behavior of Heavy Metals and Transformation of Their Speciation in Polluted Soil Receiving Simulated Acid Rain

    PubMed Central

    Zheng, Shun-an; Zheng, Xiangqun; Chen, Chun

    2012-01-01

    Heavy metals that leach from contaminated soils under acid rain are of increasing concern. In this study, simulated acid rain (SAR) was pumped through columns of artificially contaminated purple soil. Column leaching tests and sequential extraction were conducted for the heavy metals Cu, Pb, Cd, and Zn to determine the extent of their leaching as well as to examine the transformation of their speciation in the artificially contaminated soil columns. Results showed that the maximum leachate concentrations of Cu, Pb, Cd, and Zn were less than those specified in the Chinese Quality Standards for Groundwater (Grade IV), thereby suggesting that the heavy metals that leached from the polluted purple soil receiving acid rain may not pose as risks to water quality. Most of the Pb and Cd leachate concentrations were below their detection limits. By contrast, higher Cu and Zn leachate concentrations were found because they were released by the soil in larger amounts as compared with those of Pb and Cd. The differences in the Cu and Zn leachate concentrations between the controls (SAR at pH 5.6) and the treatments (SAR at pH 3.0 and 4.5) were significant. Similar trends were observed in the total leached amounts of Cu and Zn. The proportions of Cu, Pb, Cd, and Zn in the EXC and OX fractions were generally increased after the leaching experiment at three pH levels, whereas those of the RES, OM, and CAR fractions were slightly decreased. Acid rain favors the leaching of heavy metals from the contaminated purple soil and makes the heavy metal fractions become more labile. Moreover, a pH decrease from 5.6 to 3.0 significantly enhanced such effects. PMID:23185399

  4. Acid Rain: Federal Policy Action 1983-1985. A Guide to Government Documents and Commercial Sources.

    ERIC Educational Resources Information Center

    Lovenburg, Susan, Comp.

    The problems associated with acid rain as well as strategies on what to do and how to do it are addressed in this resource guide. The first section identifies and describes the U.S. agencies and congressional committees which play a role in acid rain research, legislation, and regulation. Actions already taken by the executive and legislative…

  5. STATE ACID RAIN RESEARCH AND SCREENING SYSTEM - VERSION 1.0 USER'S MANUAL

    EPA Science Inventory

    The report is a user's manual that describes Version 1.0 of EPA's STate Acid Rain Research and Screening System (STARRSS), developed to assist utility regulatory commissions in reviewing utility acid rain compliance plans. It is a screening tool that is based on scenario analysis...

  6. Sex Differences in Environmental Concern and Knowledge: The Case of Acid Rain.

    ERIC Educational Resources Information Center

    Arcury, Thomas A.; And Others

    1987-01-01

    Presents results of a telephone survey of 516 adults which focused on sex differences in concern and knowledge about one environmental issue, acid rain. The findings contradict predictions that women are more concerned about environmental issues: if there is a sex difference, men are found to be more concerned and knowledgeable about acid rain.…

  7. Acid Rain: A Resource Guide for Classroom, Laboratory, Field, and Debate Topics.

    ERIC Educational Resources Information Center

    Stoss, Frederick W.

    1987-01-01

    Provides a partially annotated bibliography of journals and book chapters which deal with acid rain. Includes selections which provide background information, ideas for introducing acid rain into science or social studies curricula, inventories of audio-visual aids, and non-print media to supplement classroom, laboratory, and field instruction.…

  8. Photosynthesis and oxidative stress in the restinga plant species Eugenia uniflora L. exposed to simulated acid rain and iron ore dust deposition: potential use in environmental risk assessment.

    PubMed

    Neves, Natália Rust; Oliva, Marco Antonio; da Cruz Centeno, Danilo; Costa, Alan Carlos; Ribas, Rogério Ferreira; Pereira, Eduardo Gusmão

    2009-06-01

    The Brazilian sandy coastal plain named restinga is frequently subjected to particulate and gaseous emissions from iron ore factories. These gases may come into contact with atmospheric moisture and produce acid rain. The effects of the acid rain on vegetation, combined with iron excess in the soil, can lead to the disappearance of sensitive species and decrease restinga biodiversity. The effects of iron ore dust deposition and simulated acid rain on photosynthesis and on antioxidant enzymes were investigated in Eugenia uniflora, a representative shrub species of the restinga. This study aimed to determine the possible utility of this species in environmental risk assessment. After the application of iron ore dust as iron solid particulate matter (SPM(Fe)) and simulated acid rain (pH 3.1), the 18-month old plants displayed brown spots and necrosis, typical symptoms of iron toxicity and injuries caused by acid rain, respectively. The acidity of the rain intensified leaf iron accumulation, which reached phytotoxic levels, mainly in plants exposed to iron ore dust. These plants showed the lowest values for net photosynthesis, stomatal conductance, transpiration, chlorophyll a content and electron transport rate through photosystem II (PSII). Catalase and superoxide dismutase activities were decreased by simulated acid rain. Peroxidase activity and membrane injury increased following exposure to acid rain and simultaneous SPM(Fe) application. Eugenia uniflora exhibited impaired photosynthetic and antioxidative metabolism in response to combined iron and acid rain stresses. This species could become a valuable tool in environmental risk assessment in restinga areas near iron ore pelletizing factories. Non-invasive evaluations of visual injuries, photosynthesis and chlorophyll a fluorescence, as well as invasive biochemical analysis could be used as markers.

  9. Energy technology and emissions control for acid rain abatement in Asia

    SciTech Connect

    Streets, D.G.

    1990-01-01

    After more than ten years of research, acid rain is a sufficiently serious problem in North America to warrant control action. The acid rain problem has become a threat to the Asian continent as well. Emissions of sulfur dioxide and nitrogen oxides are already high and announces plans for increases in coal use by countries in the region imply a major increase in emissions in the future. This will inevitably lead to greater incidence of acid rain and probably significant environmental damage in some locations. The purpose of this paper is to examine some of the issues relating to acid-rain-control technology in Asia and to suggest ways to include technology options in integrated simulation models of acid rain in Asia. 14 refs., 9 figs., 6 tabs. (FL)

  10. Interactive effects of cadmium and acid rain on photosynthetic light reaction in soybean seedlings.

    PubMed

    Sun, Zhaoguo; Wang, Lihong; Chen, Minmin; Wang, Lei; Liang, Chanjuan; Zhou, Qing; Huang, Xiaohua

    2012-05-01

    Interactive effects of cadmium (Cd(2+)) and acid rain on photosynthetic light reaction in soybean seedlings were investigated under hydroponic conditions. Single treatment with Cd(2+) or acid rain and the combined treatment decreased the content of chlorophyll, Hill reaction rate, the activity of Mg(2+)-ATPase, maximal photochemical efficiency and maximal quantum yield, increased initial fluorescence and damaged the chloroplast structure in soybean seedlings. In the combined treatment, the change in the photosynthetic parameters and the damage of chloroplast structure were stronger than those of any single pollution. Meanwhile, Cd(2+) and acid rain had the interactive effects on the test indices in soybean seedlings. The results indicated that the combined pollution of Cd(2+) and acid rain aggravated the toxic effect of the single pollution of Cd(2+) or acid rain on the photosynthetic parameters due to the serious damage to the chloroplast structure.

  11. Analysis of the combined effects of lanthanum and acid rain, and their mechanisms, on nitrate reductase transcription in plants.

    PubMed

    Xia, Binxin; Sun, Zhaoguo; Wang, Lihong; Zhou, Qing; Huang, Xiaohua

    2017-04-01

    Rare earth element (REE) pollution and acid rain are major global environmental concerns, and their spatial distributions overlap. Thus, both forms of pollution combine to act on plants. Nitrogen is important for plant growth, and nitrate reductase (NR) is a key plant enzyme that catalyzes nitrogen assimilation. Studying the combined effects of REEs and acid rain on plant nitrogen-based nutrients has important environmental significance. Here, soybean (Glycine max) plants, commonly used for toxicological studies, were exposed to lanthanum (La), a REE, and acid rain to study the NR activities and NR transcriptional levels in the roots. To explain how the pollution affected the NR transcriptional level, we simultaneously observed the contents of intracellular La and nutrient elements, protoplast morphology, membrane lipid peroxidation and intracellular pH. A combined treatment of 0.08mmol/L La and pH 4.5 acid rain increased the NR activity, decreased the NR transcriptional level, increased the intracellular nutrient elements' contents and caused deformations in membrane structures. Other combined treatments significantly decreased the aforementioned parameters and caused serious damage to the membrane structures. The variation in the amplitudes of combined treatments was greater than those of individual treatments. Compared with the control and individual treatments, combined treatments increased membrane permeability, the malondialdehyde content, and intracellular H(+) and La contents, and with an increasing La concentration or acid strength, the change in amplitude increased. Thus, the combined effects on NR gene transcription in soybean seedling roots were related to the intracellular nutrient elements' contents, protoplast morphology, membranous lipid peroxidation, intracellular pH and La content.

  12. Modeled dosage-response relationship on the net photosynthetic rate for the sensitivity to acid rain of 21 plant species.

    PubMed

    Deng, Shihuai; Gou, Shuzhen; Sun, Baiye; Lv, Wenlin; Li, Yuanwei; Peng, Hong; Xiao, Hong; Yang, Gang; Wang, Yingjun

    2012-08-01

    This study investigated the sensitivity of plant species to acid rain based on the modeled dosage-response relationship on the net photosynthetic rate (P (N)) of 21 types of plant species, subjected to the exposure of simulated acid rain (SAR) for 5 times during a period of 50 days. Variable responses of P (N) to SAR occurred depending on the type of plant. A majority (13 species) of the dosage-response relationship could be described by an S-shaped curve and be fitted with the Boltzmann model. Model fitting allowed quantitative evaluation of the dosage-response relationship and an accurate estimation of the EC(10), termed as the pH of the acid rain resulting in a P (N) 10 % lower than the reference value. The top 9 species (Camellia sasanqua, Cinnamomum camphora, etc. EC(10) ≤ 3.0) are highly endurable to very acid rain. The rare, relict plant Metasequoia glyptostroboides was the most sensitive species (EC(10) = 5.1) recommended for protection.

  13. Particle-facilitated lead and arsenic transport in abandoned mine sites soil influenced by simulated acid rain.

    PubMed

    Shaoping, Hu; Xincai, Chen; Jiyan, Shi; Yingxu, Chen; Qi, Lin

    2008-05-01

    The role of acid rain in affecting Pb and As transport from mine tailings was investigated by pumping simulated acid rain at a infiltration rate of 10.2 cm/h through soil columns. Simulated acid rain with pH of 3.0, 4.5 and 5.6 were used as leaching solutions. Results showed that 86.9-95.9% of Pb and 90-91.8% of As eluted from the columns were adsorbed by particles in the leachates. Scanning electron microscopy (SEM) analysis showed that particles released from the columns were mainly composed of flocculated aggregates and plate or rod shaped discrete grains. Transmission electron microscopy (TEM) coupled with energy dispersive X-ray analysis (EDX) showed that these particles were predominantly silicate minerals. Results from our experiments demonstrated that when rapid infiltration conditions or a rainstorm exist, particle-facilitated transport of contaminants is likely to the dominant metal transport pathway influenced by acid rain.

  14. Comparative proteomic analysis of differentially expressed proteins in β-aminobutyric acid enhanced Arabidopsis thaliana tolerance to simulated acid rain.

    PubMed

    Liu, Tingwu; Jiang, Xinwu; Shi, Wuliang; Chen, Juan; Pei, Zhenming; Zheng, Hailei

    2011-05-01

    Acid rain is a worldwide environmental issue that has seriously destroyed forest ecosystems. As a highly effective and broad-spectrum plant resistance-inducing agent, β-aminobutyric acid could elevate the tolerance of Arabidopsis when subjected to simulated acid rain. Using comparative proteomic strategies, we analyzed 203 significantly varied proteins of which 175 proteins were identified responding to β-aminobutyric acid in the absence and presence of simulated acid rain. They could be divided into ten groups according to their biological functions. Among them, the majority was cell rescue, development and defense-related proteins, followed by transcription, protein synthesis, folding, modification and destination-associated proteins. Our conclusion is β-aminobutyric acid can lead to a large-scale primary metabolism change and simultaneously activate antioxidant system and salicylic acid, jasmonic acid, abscisic acid signaling pathways. In addition, β-aminobutyric acid can reinforce physical barriers to defend simulated acid rain stress.

  15. Growth response of green and white ash seedlings to ozone, sulfur dioxide, and simulated acid rain. [Fraxinus pennsylvanica Marsh

    SciTech Connect

    Chappelka, A.H.; Chevone, B.I.; Burk, T.E. )

    1988-12-01

    Nine-week-old green (Fraxinus pennsylvanica Marsh.) and white (F. americana L.) ash were exposed to O{sub 3} and/or SO{sub 2} (control, 0.10 ppm O{sub 3}, 0.08 ppm SO{sub 2}, or 0.10 ppm O{sub 3} + 0.08 ppm SO{sub 2}) for 4 h d{sup {minus}1}, 5 d wk{sup {minus}1} in combination with simulated rain (pH 3.0, 4.3 or 5.6, 1 h d{sup {minus}1}, 2 d wk{sup {minus}1} at 0.75 cm h{sup {minus}1}) for 6 weeks, under controlled laboratory conditions, with rain applied either just before or after fumigation. Across all rain treatments, white ash biomass was suppressed by the application of O{sub 3} and cumulative shoot elongation of green ash exposed to O{sub 3} and/or SO{sub 2} was less than controls. The combination of O{sub 3} + SO{sub 2} did not affect the growth of either species more than the pollutants applied alone. Leaf area ratio (LAR) and root to shoot ratio (RSR) exhibited quadratic responses to rain pH in green ash, across all pollutant treatments. Significant pollutant {times} pH interactions occurred in leaf weight ratio (LWR) in green ash and LAR and RSR in white ash. Significant linear increases in LAR and decreases in RSR, with decreasing pH, were observed for O{sub 3} and SO{sub 2}-treated white ash. These findings are discussed relative to implications of the effects of gaseous pollutants in combination with acid rain on green and white ash growth.

  16. Sequestering CO(2) by mineral carbonation: stability against acid rain exposure.

    PubMed

    Allen, Daniel J; Brent, Geoff F

    2010-04-01

    Mineral carbonation is a potentially attractive alternative to storage of compressed CO(2) in underground repositories, known as geosequestration. Processes for the conversion of basic ores, such as magnesium silicates, to carbonates have been proposed by various researchers, with storage of the carbonate as backfill in the original mine representing a solid carbon sink. The stability of such carbon sinks against acid rain and other sources of strong acids is examined here. It is acknowledged that in the presence of strong acid, carbonates will dissolve and release carbon dioxide. A sensitivity analysis covering annual average rainfall and pH that may be encountered in industrialized areas of the United States, China, Europe, and Australia was conducted to determine maximum CO(2) rerelease rates from mineral carbonation carbon sinks. This analysis is based on a worst-case premise that is equivalent to assuming infinitely rapid kinetics of dissolution of the carbonate. The analysis shows that under any likely conditions of pH and rainfall, leakage rates of stored CO(2) are negligible. This is illustrated in a hypothetical case study under Australian conditions. It is thus proposed that sequestration by mineral carbonation can be considered to be permanent on practical human time scales. Other possible sources of acid have also been considered.

  17. [Effects of silicon on photosynthetic characteristics of Indocalamus barbatus under simulated acid rain stress].

    PubMed

    Xie, Yin-Feng; Yang, Wan-Hong; Lu, Mei-Rong; Cai, Xian-Lei; Zhou, Jian

    2008-06-01

    With Indocalamus barbatus as test material, the effects of silicon on the relative content of chlorophyll, diurnal variations of photosynthesis, and chlorophyll fluorescence were examined under simulated acid rain (pH 3.0) stress. The results showed that under acid rain stress, 20 and 500 mg x L(-1) of Na2SiO3 could prohibit the decrease of the relative content of chlorophyll to some extent; 100 mg x L(-1) of Na2SiO3 could get best effect, with the relative chlorophyll content being 22.7% higher than the control; while 500 mg x L(-1) of Na2SiO3 didn't have any effect. Under the stress, the midday depression of photosynthesis became more serious. The average daily net photosynthetic rate (Pn), stomatal limitation value (Ls), and stomata conductance (Gs) were all decreased significantly, while the intercellular CO2 concentration (Ci) increased. After treated with 20-100 mg x L(-1) of Na2SiO3, the Pn, Ls, and Gs increased to some extent while Ci decreased, and 100 mg x L(-1) of Na2SiO3 was most effective, with the average daily Pn increased by 39.2%. The maximum fluorescence of dark adaptation (Fm), maximal photochemical efficiency (Fv/Fm), potential activity (Fv/Fo), effective photochemical efficiency (Fv'/Fm'), maximum fluorescence of light adaptation (Fm') of PSII, photochemical quenching (qp), non-photochemical quenching (qN), and actual photochemical efficiency of PSII (PhiPSII) were all decreased obviously under simulated acid rain stress, but the minimum fluorescence of dark adaptation (Fo) and the minimum fluorescence of light adaptation (Fo') increased. 100 mg x L(-1) of Na2SiO3 could restrain the changes of fluorescence parameters obviously, with the Fv/Fm, Fv/Fo, Fv'/Fm' and PhiPSII increased by 35.2%, 146.2%, 55.0% and 24.3%, respectively, compared with the control. It was suggested that applying appropriate concentration of exogenous silicon to I. barbatus could efficiently relieve the decrease of its photosynthetic activity and the damage of its

  18. Correlation between microstructural characteristics and weight loss of natural stones exposed to simulated acid rain.

    PubMed

    Franzoni, Elisa; Sassoni, Enrico

    2011-12-15

    The correlation between stone microstructural characteristics and material degradation (in terms of weight loss), in given environmental conditions, was investigated. Seven lithotypes, having very different microstructural characteristics, were used. Four acidic aqueous solutions were prepared to simulate acid rain (two adding H(2)SO(4) and two adding HNO(3) to deionized water, in order to reach, for each acid, pH values of 5.0 and 4.0), and deionized water at pH=5.6 was used to simulate clean rain. Stone samples were then immersed in such aqueous solutions, the surface alteration being periodically inspected and the weight loss periodically measured. After 14 days of immersion, a good correlation was found between weight loss and the product of carbonate content and specific surface area in the starting materials. This was explained considering that this product accounts for the weight loss owing to the sample's fraction actually composed of calcite (the most soluble fraction) and the effective surface area exposed to dissolving solution (which depends on stone porosity and pore size distribution). Such correlation between stone microstructure and degradation may be useful for comparing the durability of different lithotypes, in given environmental conditions, and quantitatively predicting the weight loss of a lithotype, compared to another one. Hence, the correlation found in this study may be used to specifically tailor to various stone types, with different microstructural characteristics, some results that have been calculated in literature for specific stone types and then proposed as possibly representative for a broad category of stones with similar characteristics.

  19. Preliminary study of synergism of acid rain and diflubenzuron

    SciTech Connect

    Martin, P.J.S.; Clark, J.M.; Edman, J.D.

    1995-06-01

    Diflubenzuron{sup 1} (Dimilin{reg_sign}) was used on over 7 million acres in the U.S. in 1990 to control forest pests, particularly the gypsy moth. This chitin synthesis inhibitor affects insects and other anthropods. It is a restricted use pesticide due to its nontarget effects on aquatic macroinvertebrates. The effects of a single aerial application on nontarget aquatic macroinvertebrate communities were reviewed by Eisler (1992). Crustacea and immature insects (especially the true flies, mosquitoes, midges and black flies) are the most sensitive nontarget aquatic organisms to diflubenzuron. Diflubenzuron, N-[[4-(chlorophenyl)amino]carbonyl]-2,6-difluorobenzamide, is not the only mortality factor aquatic organisms face from human pollution. Acid deposition is a frequent stress factor in freshwater habitats in the Northeast USA. Acidic pulses can drop vernal pools (e.g., temporary, springtime, snowmelt pools) to pH levels below 3.0. Aquatic invertebrates vary in their tolerance to acidification. Reduced pH completely eliminates some species. A combination of stress factors could lead to synergistic effects, over and above the impact seen with a single stressor. The purpose of this study was to determine if there are synergist effects of diflubenzuron and lowered pH on the mortality of a nontarget aquatic organism. 11 refs., 1 fig.

  20. Health risks from acid rain: a Canadian perspective.

    PubMed Central

    Franklin, C A; Burnett, R T; Paolini, R J; Raizenne, M E

    1985-01-01

    Acidic deposition, commonly referred to as acid rain, is causing serious environmental damage in eastern Canada. The revenues from forest products, tourism and sport fishing are estimated to account for about 8% of the gross national product. The impact on human health is not as clearcut and a multi-department program on the Long-Range Transport of Airborne Pollutants (LRTAP) was approved by the federal government in June 1980. The objectives of the LRTAP program are to reduce wet sulfate deposition to less than 20 kg/ha per year in order to protect moderately sensitive areas. This will require a 50% reduction in Canadian SO2 emissions east of the Saskatchewan/Manitoba border and concomitant reductions in the eastern U.S.A. The objectives of the health sector of the program are to assess the risk to health posed by airborne pollutants which are subjected to long-range transport and to monitor the influence of abatement programs. Two major epidemiology studies were undertaken in 1983, one in which the health effects related to acute exposure to transported air pollutants were studied in asthmatic and nonasthmatic children, and another in which the effects of chronic exposure to these pollutants were studied in school children living in towns with high and low levels of pollutants. Preliminary analysis of the data do not indicate major health effects, but definitive conclusions must await final analysis. Studies on the indirect effects of acid deposition on water quality have shown that acidified lake water left standing in the plumbing system can adversely affect water quality and that federally set guidelines for copper and lead are exceeded. Flushing of the system before using the water rectifies the situation. Additional studies are planned to further delineate the magnitude of the health effects of acidified lake water. Images FIGURE 1. FIGURE 2. PMID:4076081

  1. Effects of simulated acid rain on germination, seedling growth and oxidative metabolism of recalcitrant-seeded Trichilia dregeana grown in its natural seed bank.

    PubMed

    Ramlall, Chandika; Varghese, Boby; Ramdhani, Syd; Pammenter, Norman W; Bhatt, Arvind; Berjak, Patricia; Sershen

    2015-01-01

    Increased air pollution in a number of developing African countries, together with the reports of vegetation damage typically associated with acid precipitation in commercial forests in South Africa, has raised concerns over the potential impacts of acid rain on natural vegetation in these countries. Recalcitrant (i.e. desiccation sensitive) seeds of many indigenous African species, e.g. must germinate shortly after shedding and hence, may not be able to avoid exposure to acid rain in polluted areas. This study investigated the effects of simulated acid rain (rainwater with pH adjusted to pH 3.0 and 4.5 with 70:30, H2 SO4 :HNO3 ) on germination, seedling growth and oxidative metabolism in a recalcitrant-seeded African tree species Trichilia dregeana Sond., growing in its natural seed bank. The results suggest that acid rain did not compromise T. dregeana seed germination and seedling establishment significantly, relative to the control (non-acidified rainwater). However, pH 3.0 treated seedlings exhibited signs of stress typically associated with acid rain: leaf tip necrosis, abnormal bilobed leaf tips, leaf necrotic spots and chlorosis, reduced leaf chlorophyll concentration, increased stomatal density and indications of oxidative stress. This may explain why total and root biomass of pH 3.0 treated seedlings were significantly lower than the control. Acid rain also induced changes in the species composition and relative abundance of the different life forms emerging from T. dregeana's natural seed bank and in this way could indirectly impact on T. dregeana seedling establishment success.

  2. Combined effects of lead and acid rain on photosynthesis in soybean seedlings.

    PubMed

    Hu, Huiqing; Wang, Lihong; Liao, Chenyu; Fan, Caixia; Zhou, Qing; Huang, Xiaohua

    2014-10-01

    To explore how lead (Pb) and acid rain simultaneously affect plants, the combined effects of Pb and acid rain on the chlorophyll content, chlorophyll fluorescence reaction, Hill reaction rate, and Mg(2+)-ATPase activity in soybean seedlings were investigated. The results indicated that, when soybean seedlings were treated with Pb or acid rain alone, the chlorophyll content, Hill reaction rate, Mg(2+)-ATPase activity, and maximal photochemical efficiency (F(v)/F(m)) were decreased, while the initial fluorescence (F 0) and maximum quantum yield (Y) were increased, compared with those of the control. The combined treatment with Pb and acid rain decreased the chlorophyll content, Hill reaction rate, Mg(2+)-ATPase activity, F(v)/F(m), and Y and increased F 0 in soybean seedlings. Under the combined treatment with Pb and acid rain, the two factors showed additive effects on the chlorophyll content in soybean seedlings and exhibited antagonistic effects on the Hill reaction rate. Under the combined treatment with high-concentration Pb and acid rain, the two factors exhibited synergistic effects on the Mg(2+)-ATPase activity, F 0, F v/F m, as well as Y. In summary, the inhibition of the photosynthetic process is an important physiological basis for the simultaneous actions of Pb and acid rain in soybean seedlings.

  3. Effect of simulated acid rain on the litter decomposition of Quercus acutissima and Pinus massoniana in forest soil microcosms and the relationship with soil enzyme activities.

    PubMed

    Wang, Congyan; Guo, Peng; Han, Guomin; Feng, Xiaoguang; Zhang, Peng; Tian, Xingjun

    2010-06-01

    With the continuing increase in human activities, ecologists are increasingly interested in understanding the effects of acid rain on litter decomposition. Two dominant litters were chosen from Zijin Mountain in China: Quercus acutissima from a broad-leaved forest and Pinus massoniana from a coniferous forest. The litters were incubated in microcosms and treated with simulated acid rain (gradient pH levels). During a six-month incubation, changes in chemical composition (i.e., lignin, total carbohydrate, and nitrogen), litter mass losses, soil pH values, and activities of degradative enzymes were determined. Results showed that litter mass losses were depressed after exposure to acid rain and the effects of acid rain on the litter decomposition rates of needles were higher than on those of leaves. Results also revealed that simulated acid rain restrained the activities of cellulase, invertase, nitrate reductase, acid phosphatase, alkaline phosphatase, polyphenol oxidase, and urease, while it enhanced the activities of catalase in most cases during the six-month decomposition process. Catalase and polyphenol oxidase were primarily responsible for litter decomposition in the broad-leaved forest, while invertase, nitrate reductase, and urease were primarily responsible for litter decomposition in the coniferous forest. The results suggest acid rain-restrained litter decomposition may be due to the depressed enzymatic activities. According to the results of this study, soil carbon in subtropical forests would accumulate as a long-term consequence of continued acid rain. This may presumably alter the balance of ecosystem carbon flux, nutrient cycling, and humus formation, which may, in turn, have multiple effects on forest ecosystems.

  4. [Response of POD and CAT during seeds of rice, wheat and rape germination on acid rain stress].

    PubMed

    Wang, Li-hong; Huang, Xiao-hua; Zhou, Qing

    2005-11-01

    The effects of simulated acid rain (pH 2.5 - 5.0) on the activities of POD and CAT were investigated during germination of rice (O. sativa), wheat (T. aestivum) and rape (B. chinensis var. oleifera) seeds. Compared with the control (CK), the amplitude of the change in the activity of CAT and POD is that rice (28.8%, 31.7%) < wheat (34.7%, 48.3%) < rape (79.3%, 50.0%), respectively. The pH significantly different (p < 0.05) from CK follows the order: rice (3.5) > wheat (4.0) > rape (5.0). All of these revealed that the ability of resisting acid rain stress is that rice is stronger than wheat and rape is the worst. Under the same condition, the amplitude of the change in the activity of CAT is more sensitivity toward acid rain stress than that of POD. The difference in free radicals removed by these 3 species is one of the reasons why the germinating indexes behaved differently.

  5. Effects of acid rain on forest nutrient status. Final report

    SciTech Connect

    Johnson, D.W.; Cole, D.W.

    1985-04-01

    In five forest sites (three in eastern Tennessee and two in western Washington) the effect of natural carbonic acid production on soil leaching was equaled or exceeded by that of atmospheric acid inputs. In a nitrogen-fixing red alder site in Washington, however, internal leaching by nitrification and nitric acid formation far exceeded atmospheric H/sup +/ inputs at any site. All other sites retained NO/sub 3//sup -/, and soil SO/sub 4//sup 2 -/ adsorption reduced the effectiveness of atmospheric H/sub 2/SO/sub 4/ inputs on soil leaching in two of the Tennessee sites and in the Washington red alder site. Atmospheric sulfur inputs exceeded the forest sulfur requirement in all five sites. Decomposer invertebrates appeared to be affected negatively by unrealistically large applications of SO/sub 4//sup 2 -/, either as KHSO/sub 4/ or K/sub 2/SO/sub 4/. Forest floor buffering prevented large changes in pH with acid SO/sub 4//sup 2 -/ treatments. Results indicate that effects of acid deposition on decomposer invertebrates are unlikely except at input levels much higher than ambient.

  6. 1997 Canadian acid rain assessment. Volume 4: The effects on Canada`s forests

    SciTech Connect

    Hall, P.

    1997-12-31

    This report reviews the state of acid rain assessment related to Canadian forests as it has progressed since the last assessment carried out in 1990. The assessment also highlights key policy issues and the uncertainties associated with addressing them. Sections of the report cover the following: Acid rain and current forest decline in coastal birch, sugar maple, and high elevation forests; the effects of acid rain on tree physiology and soil chemistry; results of forest health monitoring in national, North American, Ontario, and Quebec networks; the critical loads or levels of acid deposition, with reference to case studies; and international involvement in acid rain research and abatement. Finally, research and information needs are identified.

  7. Characterization and Evaluation of Acid Rain in East Central Florida from 1978 to 1995 and Evaluation of Some Chromatographic/Spectroscopic Results from Leachate Samples from CELSS

    NASA Technical Reports Server (NTRS)

    Madsen, Brooks C.

    1996-01-01

    The results of monitoring the chemical composition of rain in east-central Florida have shown that the rain is moderately acid. The measured acidity of rain is less than that observed in other regions of the U. S., however, it does suggest that the level of acidity is substantial. The annual chemical composition of rain at UCF and at KSC has shown moderate variability. Extreme daily and monthly variations are observed, however these variations are not addressed here. The total ionic composition of rain collected at FL99 is greater than that for rain collected at UCF, however this can be accounted for by site proximity to the ocean with the accompanying marine influence. Difference in acidity data collected from the UCF and FL99 sites which are separated by 50 km may be due in part to the differences that have been observed between laboratory and field pH measurements. Trend assessment for precipitation composition requires evaluation of data that covers some minimum time period. In fact, the subdivision of the multi-year UCF record into individual 10 year records as described above can lead to the conclusion that a significant increase, a significant decrease or no trend exists for acidity depending upon the time period chosen for evaluation. Trend evaluation has also been accomplished by linear and nonlinear regression analysis using monthly volume weighted average concentrations and deposition using the UCF data set and some of the Florida NADP data set.

  8. From the Fur Trade to Acid Rain: A Study of Canadian Natural Resources.

    ERIC Educational Resources Information Center

    Winans, Linda

    1988-01-01

    Presents a teaching module for upper elementary students that devotes eight class periods of study to Canadian resources. Includes study of the Canadian fur trade, fishing industry, forestry, and the problems caused by acid rain. Includes the unit evaluation. (DB)

  9. Supporting document for the Canada-wide acid rain strategy for post-2000

    SciTech Connect

    Not Available

    1998-01-01

    This report presents background and other information on the Canada-Wide Acid Rain Strategy for Post-2000, which puts in place a framework for addressing the remaining acid rain problem in eastern Canada, for ensuring that new acid rain problems do not occur elsewhere in Canada, and for ensuring that Canada meets its international commitments on acid rain. Background information is included on the first and second Sulphur Protocols of 1985 and 1994, the 1991 Canada-United States Air Quality Agreement, and progress to date in meeting emission targets. Key features of the strategy are then presented with respect to such matters as sulphur dioxide emission reductions, pollution prevention, and research. Finally, the positions of members of the multi-stakeholder task group who developed the supporting documentation for the strategy are outlined.

  10. Analysis of Natural Buffer Systems and the Impact of Acid Rain

    ERIC Educational Resources Information Center

    Powers, David C.; Yoder, Claude H.; Higgs, Andrew T.; Obley, Matt L.; Hess, Kenneth R.; Leber, Phyllis A.

    2005-01-01

    The environmental significance of acid rain on water systems of different buffer capacities is discussed. The most prevalent natural buffer system is created by the equilibrium between carbonate ions and carbon dioxide.

  11. Environmental Externalities in Electric Power Markets: Acid Rain, Urban Ozone, and Climate Change

    EIA Publications

    1995-01-01

    This article discusses the emissions resulting from the generation of electricity by utilities and their role in contributing to the environmental problems of acid rain, urban ozone, and climate change.

  12. Integrated Title V/acid rain permits: Transitioning through initial permit issuance and reopenings

    SciTech Connect

    Bloomfield, C.

    1995-12-31

    Titles IV and V of the Clean Air Act Amendments of 1990 (Act or CAA) created two new stationary source permitting programs, one specific to acid rain (Title IV), and a second for operating permits in general (Title V). The Phase 2 portion of the acid rain program was designed to be implemented through the Title V operating permit program, thereby subjecting all Phase 2 acid rain sources to the requirements of Title V. Permits issued pursuant to Phase 2 of the acid rain program will be viewed as a self-contained portion of the Title V operating permit and will be governed by regulations promulgated under both Title IV and Title V. The requirements imposed by Title IV may not always be consistent with the broader operating permit program requirements of Title V, and when inconsistency occurs, the acid rain requirements will take precedence. This nonalignment will perhaps be most apparent during two stages of initial permitting: (1) the transition period following Title V program approval when permit application, issuance, and effective dates differ between the two programs, and (2) at the point when acid rain permits must be reopened to incorporate Phase 2 NO{sub x} requirements. This paper explores strategies for streamlining implementation of the two programs with particular focus on these two coordination issues.

  13. [Responses of rhizosphere nitrogen and phosphorus transformations to different acid rain intensities in a hilly red soil tea plantation].

    PubMed

    Chen, Xi; Chen, Fu-sheng; Ye, Su-qiong; Yu, Su-qin; Fang, Xiang-min; Hu, Xiao-fei

    2015-01-01

    Tea (Camellia sinensis) plantation in hilly red soil region has been long impacted by acid deposition, however its effects on nitrogen (N) and phosphorus (P) transformations in rhizosphere soils remain unclear. A 25-year old tea plantation in a typical hilly red soil region was selected for an in situ simulation experiment treated by pH 4.5, pH 3.5, pH 2.5 and control. Rhizosihere and bulk soils were collected in the third year from the simulated acid deposition experiment. Soil mineral N, available P contents and major enzyme activities were analyzed using the chemical extraction and biochemical methods, and N and P mineralization rates were estimated using the indoor aerobic incubation methods. Our results showed that compared to the control, the treatments of pH 4.5, pH 3.5 and pH 2.5, respectively decreased 7.1%, 42.1% and 49.9% NO3(-)-N, 6.4%, 35.9% and 40.3% mineral N, 10.5%, 41.1% and 46.9% available P, 18.7%, 30.1% and 44.7% ammonification rate, 3.6%, 12.7% and 38.8% net N-mineralization rate, and 31.5%, 41.8% and 63.0% P mineralization rate in rhizosphere soils; however, among the 4 treatments, rhizosphere soil nitrification rate was not significantly different, the rhizosphere soil urease and acid phosphatase activities generally increased with the increasing intensity of acid rain (P<0.05). In bulk soil, compared with the control, the treatments of pH 4.5, pH 3.5 and pH 2.5 did not cause significant changes in NO3(-)-N, mineral N, available P as well as in the rates of nitrification, ammonification, net N-mineralization and P mineralization. With increasing the acid intensity, the rhizosphere effects of NH4+-N, NO3(-)-N, mineral N, ammonification and net N-mineralization rates were altered from positive to negative effects, those of urease and acid phosphatease showed the opposite trends, those of available P and P mineralization were negative and that of nitrification was positive. In sum, prolonged elevated acid rain could reduce N and P transformation

  14. Carbon fluxes in an acid rain impacted boreal headwater catchment

    NASA Astrophysics Data System (ADS)

    Marx, Anne; Hintze, Simone; Jankovec, Jakub; Sanda, Martin; Dusek, Jaromir; Vogel, Tomas; van Geldern, Robert; Barth, Johannes A. C.

    2016-04-01

    Terrestrial carbon export via inland aquatic systems is a key process in the budget of the global carbon cycle. This includes loss of carbon to the atmosphere via gas evasion from rivers or reservoirs as well as carbon fixation in freshwater sediments. Headwater streams are the first endmembers of the transition of carbon between soils, groundwater and surface waters and the atmosphere. In order to quantify these processes the experimental catchment Uhlirska (1.78 km2) located in the northern Czech Republic was studied. Dissolved inorganic, dissolved organic and particulate organic carbon (DIC, DOC, POC) concentrations and isotopes were analyzed in ground-, soil -and stream waters between 2014 and 2015. In addition, carbon dioxide degassing was quantified via a stable isotope modelling approach. Results show a discharge-weighted total carbon export of 31.99 g C m-2 yr-1 of which CO2 degassing accounts 79 %. Carbon isotope ratios (δ13C) of DIC, DOC, and POC (in ‰ VPDB) ranged from -26.6 to -12.4 ‰ from -29.4 to -22.7 ‰ and from -30.6 to -26.6 ‰ respectively. The mean values for DIC are -21.8 ±3.8 ‰ -23.6 ±0.9 ‰ and -19.5 ±3.0 ‰ for soil, shallow ground and surface water compartments. For DOC, these compartments have mean values of -27.1 ±0.3 ‰ -27.0 ±0.8 ‰ and -27.4 ±0.7 ‰Ṁean POC value of shallow groundwaters and surface waters are -28.8 ±0.8 ‰ and -29.3 ±0.5 ‰ respectively. These isotope ranges indicate little turnover of organic material and predominant silicate weathering. The degassing of CO2 caused an enrichment of the δ13C-DIC values of up to 6.8 ‰ between a catchment gauge and the catchment outlet over a distance of 866 m. In addition, the Uhlirska catchment has only negligible natural sources of sulphate, yet SO42- accounts for 21 % of major stream water ions. This is most likely a remainder from acid rain impacts in the area.

  15. A Simulation of the Interaction of Acid Rain with Soil Minerals

    ERIC Educational Resources Information Center

    Schilling, Amber L.; Hess, Kenneth R.; Leber, Phyllis A.; Yoder, Claude H.

    2004-01-01

    The atmospheric issue of acid rains is subjected to a five-part laboratory experiment by concentrating on the chemistry of the infiltration process of acid rainwater through soils. This procedure of quantitative scrutiny helps students realize the efficacy of soil minerals in the consumption of surplus acidity in rainwater.

  16. Marginal bleaching of thalli of Rhizocarpon as evidence for acid rain in the Norra Storfjället, Sweden.

    PubMed

    Mahaney, W C; Wilson, E; Boyer, M G; Hancock, R G

    1995-01-01

    Recent lichen surveys in the foreland of The Syterbäcken glacier reveal that the crustose lichens, principally species of Rhizocarpon section Rhizocarpon, exhibit marginal bleaching, readily distinguishable from normal pigmented forms. The largest elliptical thallus of Rhizocarpon measured 290 mm maximum diameter on a bedrock outcrop beyond the margin of Little Ice Age moraines in the upper Syterbäcken Valley. Many small and large thalli of Rhizocarpon suffered damage to the periphery of individual thalli. We examine here some of the possible hypotheses explaining these occurrences. Among others, these are bedrock lithology, ice crystal blasting, long-term snowbank cover, ultraviolet exposure and acid rain. While at this time none of the possibilities can be ruled out entirely, acid rain would appear to be at least one of the factors involved. Acid rain, which is known to produce a soil pH as low as 3.3 in the field area, appears to provide a high input of H(+) ions that the lichen algal component cannot withstand. However, the lack of similar effects on associated foliose or fruticose forms raises the possibility that perhaps two or more factors specific to the environment of Rhizocarpon are operating.

  17. Calcium affecting protein expression in longan under simulated acid rain stress.

    PubMed

    Pan, Tengfei; Li, Yongyu; Ma, Cuilan; Qiu, Dongliang

    2015-08-01

    Longan (Dimocarpus longana Lour. cv. Wulongling) of uniform one-aged seedlings grown in pots were selected to study specific proteins expressed in leaves under simulated acid rain (SiAR) stress and exogenous Ca(2+) regulation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) results showed that there was a protein band specifically expressed under SiAR of pH 2.5 stress for 15 days with its molecular weight of about 23 kD. A 17 kD protein band specifically expressed after SiAR stress 5 days. Compared with pH 2.5, the pH 3.5 of SiAR made a less influence to protein expression. Two-dimensional electrophoresis (2-DE) results showed that six new specific proteins including C4 (20.2 kD pI 6.0), F (24 kD pI 6.35), B3 (22.3 kD pI 6.35), B4 (23.5 kD pI 6.5), C5 (21.8 kD pI 5.6), and C6 (20.2 kD pI 5.6) specifically expressed. C4 always expressed during SiAR stress. F expressed under the stress of pH 2.5 for 15 days and expressed in all pH SiAR stress for 20 days. The expression of proteins including B3, C5, and C6 was related to pH value and stress intensity of SiAR. The expression of B4 resulted from synergistic effects of SiAR and Ca. The expression of G1 (Mr 19.3 kD, pI 4.5), G2 (Mr 17.8 kD, pI 4.65), G3 (Mr 16.6 kD, pI 4.6), and G4 (Mr 14.7 kD, pI 4.4) enhanced under the treatment of 5 mM ethylene glycol tetraacetic acid (EGTA) and 2 mM chlorpromazine (CPZ). These proteins showed antagonistic effects and might be relative to the Ca-calmodulin (Ca-CaM) system of longan in response to SiAR stress.

  18. EFFECT OF AN ACID RAIN ENVIRONMENT ON LIMESTONE SURFACES.

    USGS Publications Warehouse

    Mossotti, Victor G.; Lindsay, James R.; Hochella, Michael F.

    1987-01-01

    Salem limestone samples were exposed to weathering for 1 y in several urban and one rural environments. Samples exposed in the rural location were chemically indistinguishable from the freshly quarried limestone, whereas all samples collected from urban exposure sites developed gypsum stains on the ground-facing surfaces where the stones were not washed by precipitation. The gas-solid reaction of SO//2 with calcite was selected for detailed consideration. It appears from the model that under arid conditions, the quantity of stain deposited on an unwashed surface is independent of atmospheric SO//2 concentration once the surface has been saturated with gypsum. Under wet conditions, surface sulfation and weight loss are probably dominated by mechanisms involving wet stone. However, if the rain events are frequent and delimited by periods of dryness, the quantity of gypsum produced by a gas-solid reaction mechanism should correlate with both the frequency of rain events and the atmospheric SO//2 level.

  19. The combined effects of urea application and simulated acid rain on soil acidification and microbial community structure.

    PubMed

    Liu, Xingmei; Zhou, Jian; Li, Wanlu; Xu, Jianming; Brookes, Philip C

    2014-05-01

    Our aim was to test the effects of simulated acid rain (SAR) at different pHs, when applied to fertilized and unfertilized soils, on the leaching of soil cations (K, Ca, Mg, Na) and Al. Their effects on soil pH, exchangeable H(+) and Al(3+) and microbial community structure were also determined. A Paleudalfs soil was incubated for 30 days, with and without an initial application of urea (200 mg N kg(-1)soil) as nitrogen (N) fertilizer. The soil was held in columns and leached with SAR at three pH levels. Six treatments were tested: SAR of pH 2.5, 4.0 and 5.6 leaching on unfertilized soil (T1, T2 and T3), and on soils fertilized with urea (T4, T5 and T6). Increasing acid inputs proportionally increased cation leaching in both unfertilized and fertilized soils. Urea application increased the initial Ca and Mg leaching, but had no effect on the total concentrations of Ca, Mg and K leached. There was no significant difference for the amount of Na leached between the different treatments. The SAR pH and urea application had significant effects on soil pH, exchangeable H(+) and Al(3+). Urea application, SAR treated with various pH, and the interactions between them all had significant impacts on total phospholipid fatty acids (PLFAs). The highest concentration of total PLFAs occurred in fertilized soils with SAR pH5.6 and the lowest in soils leached with the lowest SAR pH. Soils pretreated with urea then leached with SARs of pH 4.0 and 5.6 had larger total PLFA concentrations than soil without urea. Bacterial, fungal, actinomycete, Gram-negative and Gram-positive bacterial PLFAs had generally similar trends to total PLFAs.

  20. Quantum mechanical study of atmospheric nitrogen oxides and nitric acid: Implications on acid rain

    SciTech Connect

    Richardson, M.D.; Davey, C.A.; Evanseck, J.D.

    1996-12-31

    The energetics of the nonhydrated and monohydrated reaction NO2 + OH {r_arrow} HNO3 were studied using computational methods. Energetic and structural data were obtained using high level ab initio calculations (up to MP4 for energetics). The activation energy was calculated to be around 8 kcal/mol for the nonhydrated system, but the presence of a single water molecule completely eliminated the barrier to nitric acid formation. The hydration of this atmospheric reaction significantly stabilizes the transition structure, leading to an activation energy of about -1 kcal/mol for the reaction. This suggests that enthalpically the reactants may spontaneously form nitric acid in the lower atmosphere where water is available for catalysis, resulting in further production of acid rain.

  1. Effects and mechanisms of the combined pollution of lanthanum and acid rain on the root phenotype of soybean seedlings.

    PubMed

    Sun, Zhaoguo; Wang, Lihong; Zhou, Qing; Huang, Xiaohua

    2013-09-01

    Rare earth pollution and acid rain pollution are both important environmental issues worldwide. In regions which simultaneously occur, the combined pollution of rare earth and acid rain becomes a new environmental issue, and the relevant research is rarely reported. Accordingly, we investigated the combined effects and mechanisms of lanthanum ion (La(3+)) and acid rain on the root phenotype of soybean seedlings. The combined pollution of low-concentration La(3+) and acid rain exerted deleterious effects on the phenotype and growth of roots, which were aggravated by the combined pollution of high-concentration La(3+) and acid rain. The deleterious effects of the combined pollution were stronger than those of single La(3+) or acid rain pollution. These stronger deleterious effects on the root phenotype and growth of roots were due to the increased disturbance of absorption and utilization of mineral nutrients in roots.

  2. Soil-calcium depletion linked to acid rain and forest growth in the eastern United States

    USGS Publications Warehouse

    Lawrence, Gregory B.; Huntington, T.G.

    1999-01-01

    Since the discovery of acid rain in the 1970's, scientists have been concerned that deposition of acids could cause depletion of calcium in forest soils. Research in the 1980's showed that the amount of calcium in forest soils is controlled by several factors that are difficult to measure. Further research in the 1990's, including several studies by the U.S. Geological Survey, has shown that (1) calcium in forest soils has decreased at locations in the northeastern and southeastern U.S., and (2) acid rain and forest growth (uptake of calcium from the soil by roots) are both factors contributing to calcium depletion.

  3. Federal-provincial agreements for the Eastern Canada Acid Rain Program: Annual report 1997

    SciTech Connect

    1998-12-31

    This report on the Eastern Canada Acid Rain Program compares the previous year`s emissions of sulphur dioxide in the 7 easternmost provinces to the emission targets in the program. The objective is to cap sulphur dioxide (SO{sub 2}) emissions until the year 2000. Coupled with the US Acid Rain Program it is intended to protect sensitive ecosystems from acid deposition. This report discusses emissions for the latest year, concerns, and steps to be taken. Statistical tables give emissions by province and industry, with information for some major air pollution sources in mineral extraction or electric power generation.

  4. Suppression of rice methane emission by sulfate deposition in simulated acid rain

    NASA Astrophysics Data System (ADS)

    Gauci, Vincent; Dise, Nancy B.; Howell, Graham; Jenkins, Meaghan E.

    2008-09-01

    Sulfate in acid rain is known to suppress methane (CH4) emissions from natural freshwater wetlands. Here we examine the possibility that CH4 emissions from rice agriculture may be similarly affected by acid rain, a major and increasing pollution problem in Asia. Our findings suggest that acid rain rates of SO42- deposition may help to reduce CH4 emissions from rice agriculture. Emissions from rice plants treated with simulated acid rain at levels of SO42- consistent with the range of deposition in Asia were reduced by 24% during the grain filling and ripening stage of the rice season which accounts for 50% of the overall CH4 that is normally emitted in a rice season. A single application of SO42- at a comparable level reduced CH4 emission by 43%. We hypothesize that the reduction in CH4 emission may be due to a combination of effects. The first mechanism is that the low rates of SO42- may be sufficient to boost yields of rice and, in so doing, may cause a reduction in root exudates to the rhizosphere, a key substrate source for methanogenesis. Decreasing a major substrate source for methanogens is also likely to intensify competition with sulfate-reducing microorganisms for whom prior SO42- limitation had been lifted by the simulated acid rain S deposition.

  5. Effects of acid rain, alone and in combination with gaseous pollutants, on growth and yield of crop plants

    SciTech Connect

    Shriner, D.S.; Johnston, J.W. Jr.

    1985-01-01

    Greenhouse, growth chamber, and field experiments were conducted to determine the response of crop plants to levels of acidity in simulated rain. The major objectives were: to determine the levels of acidity in rain that alter crop productivity; to evaluate varietal differences in crop response; and to determine the response of crop plants to the combined stress of acid rain and gaseous pollutants, primarily ozone. Results showed additive effects rather than synergistic ones.

  6. 40 CFR 74.3 - Relationship to the Acid Rain program requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 17 2014-07-01 2014-07-01 false Relationship to the Acid Rain program requirements. 74.3 Section 74.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) SULFUR DIOXIDE OPT-INS Background and Summary § 74.3 Relationship to the Acid...

  7. 40 CFR 74.3 - Relationship to the Acid Rain program requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Relationship to the Acid Rain program requirements. 74.3 Section 74.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) SULFUR DIOXIDE OPT-INS Background and Summary § 74.3 Relationship to the Acid...

  8. Is There Scientific Consensus on Acid Rain? -- Excerpts from Six Governmental Reports.

    ERIC Educational Resources Information Center

    Environmental Education Report and Newsletter, 1986

    1986-01-01

    Compiles a series of direct quotations from six governmental reports that reflect a scientific consensus on major aspects of acid deposition. Presents the statements in a question and answer format. Also reviews the sources, extent, and effects of acid rain. (ML)

  9. 40 CFR 74.3 - Relationship to the Acid Rain program requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Relationship to the Acid Rain program requirements. 74.3 Section 74.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) SULFUR DIOXIDE OPT-INS Background and Summary § 74.3 Relationship to the Acid...

  10. 40 CFR 74.3 - Relationship to the Acid Rain program requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 17 2012-07-01 2012-07-01 false Relationship to the Acid Rain program requirements. 74.3 Section 74.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) SULFUR DIOXIDE OPT-INS Background and Summary § 74.3 Relationship to the Acid...

  11. 40 CFR 74.3 - Relationship to the Acid Rain program requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Relationship to the Acid Rain program requirements. 74.3 Section 74.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) SULFUR DIOXIDE OPT-INS Background and Summary § 74.3 Relationship to the Acid...

  12. Simulated acid rain alters litter decomposition and enhances the allelopathic potential of the invasive plant Wedelia trilobata (Creeping Daisy)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Invasive species and acid rain cause global environmental problems. Limited information exists, however, concerning the effects of acid rain on the invasiveness of these plants. For example, creeping daisy, an invasive exotic allelopathic weed, has caused great damage in southern China where acid ra...

  13. Acid rain program: CEMS submission instructions for monitoring plans, certification test notifications, and quarterly reports

    SciTech Connect

    1995-05-12

    The Acid Rain Program regulations require all affected utility units to continuously measure, record and report SO2, NOx, volumetric flow data and CO2 emissions. All affected units also must continuously measure and record opacity, and must report opacity exceedances to the appropriate State or Local Agency. To ensure that your CEMS and fuel flowmeters are performing at an acceptable level, and providing quality assured data, you are required under 40 CFR 75.53, 75.62 (a) to submit a monitoring plan and certification test data for acid rain CEM certificaton. The purpose of this handbook is to help you fulfill your requirements under the Acid Rain Program. This handbook will walk you through the necessary steps for gaining CEMS certification, including filling out and mailing the proper forms, administering the required tests, and applying for certification and sending in electronic data to EPA.

  14. Effects of simulated acid rain on the morphology, phenology and dry biomass of a local variety of maize (Suwan-1) in Southwestern Nigeria.

    PubMed

    Macaulay, Babajide Milton; Enahoro, Gloria Ebarunosen

    2015-10-01

    Effects of acid rain on the morphology, phenology and dry biomass of maize (Suwan-1 variety) were investigated. The maize seedlings were subjected to different pH treatments (1.0, 2.0, 3.0, 4.0, 5.0 and 6.0) of simulated acid rain (SAR) with pH 7.0 as the control for a period of 90 days. The common morphological defects due to SAR application were necrosis and chlorosis. It was observed that necrosis increased in severity as the acidity increased whilst chlorosis was dominant as the acidity decreased. SAR encouraged rapid floral and cob growth but with the consequence of poor floral and cob development in pH 1.0 to 3.0 treatments. The result for the dry biomass indicates that pH treatments 2.0 to 7.0 for total plant biomass were not significantly different (P > 0.05) from one another, but were all significantly higher (P < 0.05) than pH 1.0. Therefore, it may be deduced that Suwan-1 has the potential to withstand acid rain but with pronounced morphological and phenological defects which, however, have the capacity to reduce drastically the market value of the crop. Therefore, it may be concluded that Suwan-1 tolerated acid rain in terms of the parameters studied at pH 4.0 to 7.0 which makes it a suitable crop in acid rain-stricken climes. This research could also serve as a good reference for further SAR studies on maize or other important cereals.

  15. The major role of dust in explaining 1954--1993 acid rain trends

    SciTech Connect

    Stensland, G.J.

    1995-12-31

    Calcium and other base cation levels in air and precipitation from the 1950`s to the 1990`s can be as important as sulfate and other acidic species in understanding acid rain trends (or basic rain trends). Precipitation quality data, air quality data, and estimates of sources of dust emissions are used to address the issue of calcium trends in the atmosphere. The apparent downward trend for calcium in precipitation from the 1950`s to the 1970`s is suggested to be due mainly to a change in sample collection methods while the decrease since the mid-1970`s is due to a real decrease in atmospheric calcium dust levels in the atmosphere.

  16. Acid rain and emissions trading. Implementing a market approach to pollution control

    SciTech Connect

    Raufer, R.K.; Feldman, S.L.

    1987-01-01

    A key policy proposal in the current debate over the control of acid rain and other pollutants is permitting companies to buy, sell, or lease emissions rights or ''credits.'' This book is a study of the theoretical and practical difficulties involved in the creation of a national emissions trading program, a survey of the positions of the utilities and public regulatory commissions toward such a program, and estimates of the potential environmental and economic impact of emissions trading. The authors demonstrate the advantages of controlling acid rain through a market approach rather than through a regulatory approach.

  17. The influence of polarization on millimeter wave propagation through rain. Ph.D Thesis. Interim Report

    NASA Technical Reports Server (NTRS)

    Wiley, P. H.; Bostian, C. W.; Stutzman, W. L.

    1973-01-01

    The influence of polarization on millimeter wave propagation is investigated from both an experimental and a theoretical viewpoint. First, previous theoretical and experimental work relating to the attenuation and depolarization of millimeter waves by rainfall is discussed. Considerable detail is included in the literature review. Next, a theoretical model is developed to predict the cross polarization level during rainfall from the path average rain rate and the scattered field from a single raindrop. Finally, data from the VPI and SU depolarization experiment are presented as verification of the new model, and a comparison is made with other theories and experiments. Aspects of the new model are: (1) spherical rather than plane waves are assumed, (2) the average drop diameter is used rather than a drop size distribution, and (3) it is simple enough so that the effect which changing one or more parameters has on the crosspolarization level is easily seen.

  18. Effect of acid rain on building material of the El Tajín archaeological zone in Veracruz, Mexico.

    PubMed

    Bravo A, H; Soto A, R; Sosa E, R; Sánchez A, P; Alarcón J, A L; Kahl, J; Ruíz B, J

    2006-11-01

    Three limestone slabs (approx. 20 cm2 each) were extracted from the El Tajin archaeological zone in Veracruz, Mexico. X-ray diffraction analysis revealed three components: calcite (81.2%), quartz (17.9%) and feldspar (0.9%). Calcite content by x-ray diffraction analysis was slightly higher than that determined by chemical reaction between the limestone sample and nitric acid. The latter analysis, carried out in triplicate, yielded a calcite content of 77.1%. Mean water absorption, density and porosity of the limestone samples were also determined. Dissolution of limestone samples was investigated using an experimental rainfall simulation chamber, in which the stone samples were irrigated with artificial rain matching the pH and the ionic composition with 40 rainfall samples collected at El Tajin from August 18, 2002, to April 9, 2003. According to calcium and bicarbonate net concentrations found in the effluent of the chamber, a chemical mechanism by which limestone at El Tajin is dissolved by acid rain is proposed. A model used to investigate the air transport pathways corresponding to precipitation events at El Tajin shows that air parcels come mainly from the Gulf of Mexico, although no directional preference is evident for acidic vs. non-acidic events.

  19. Atmospheric deposition and canopy exchange of anions and cations in two plantation forests under acid rain influence

    NASA Astrophysics Data System (ADS)

    Shen, Weijun; Ren, Huili; Darrel Jenerette, G.; Hui, Dafeng; Ren, Hai

    2013-01-01

    Acid deposition as a widely concerned environmental problem in China has been less studied in plantation forests compared to urban and secondary forests, albeit they constitute 1/3 of the total forested areas of the country. We measured the rainwater amount and chemistry outside and beneath the canopies of two widely distributed plantations (Acacia mangium and Dimocarpus longan) in the severe acid rain influenced Pearl River Delta region of southeastern China for two years. Our results showed that the frequency of acid rain was 96% on the basis of pH value <5.6. The volume-weighted mean (vwm) pH was 4.62 and higher in the dry (Oct.-Mar.) than in the wet (Apr.-Sep.) seasons. The major acidic anion was sulfate with vwm concentration of 140 μeq l-1 and annual deposition flux of 110.3 kg ha-1 yr-1. The major neutralizing cations were calcium (94.8 μeq l-1 and 28 kg ha-1 yr-1) and ammonium (41.2 μeq l-1 and 11.7 kg ha-1 yr-1). Over 95% of these major acidic anions and neutralizing cations were derived from anthropogenic and terrestrial sources as a result of industrial, agricultural and forestry activities. Plantation canopy had marked impacts on rainwater chemistry, with the measured anion and cation concentrations being significantly enriched in throughfall (TF) and stemflow (SF) rainwater by 1.4 (for NO) to 20-fold (for K+) compared to those in bulk precipitation (BP). Dry deposition generally contributed about 13-22% of the total deposition while canopy leaching mainly occurred for K+ (>88%) and NH (10-38%). The two tree species showed distinct impacts on rainfall redistribution and rainwater chemistry due to their differences in canopy architecture and leaf/bark texture, suggesting that species-specific effects should not be overlooked while assessing the acid deposition in forested areas.

  20. Effects of ozone and simulated acid rain on birch seedling growth and formation of ectomycorrhizae.

    PubMed

    Keane, K D; Manning, W J

    1988-01-01

    Four-week-old paper birch (Betula papyrifera Marsh.) seedlings, inoculated or non-inoculated with the ectomycorrhizal fungus Pisolithus tinctorius (Pers.) Coker & Couch and grown in steamed or non-steamed soil, were exposed to ozone (O(3)) and/or simulated acid rain (SAR). Plants were exposed to O(3) for 7 h per day on 5 days per week for 12 weeks. O(3) concentrations were maintained between 0.06 and 0.08 ppm. SAR was applied 10 min per day on 2 days per week. O(3), SAR, soil regime and mycorrhizal treatment did not significantly affect any of the measured variables. Interactions between O(3) and SAR, SAR and mycorrhizal treatment, soil regime and mycorrhizal treatment and ozone and soil regime had significant effects. Treatment of seedlings with pH 3.5 SAR caused increases in growth which were more apparent in birch exposed to O(3). Mucorrhizal treatment caused increased growth in non-steamed soil, while growth appeared to decrease in steamed soil. Birch seedlings grew much better in steamed soil. The implications of increased growth in steamed soil may demonstrate the importance of looking at the secondary effects of pollutants on soil-borne organisms.

  1. Acid rains over semi-urban atmosphere at eastern Himalaya and near coast of Bay of Bengal and alkaline rains over typical urban atmosphere in India: A study on precipitation chemistry during monsoon, 2013

    NASA Astrophysics Data System (ADS)

    Roy, Arindam; Chatterjee, Abhijit; Sarkar, Chirantan; Ghosh, Sanjay; Raha, Sibaji

    A study has been made on precipitation chemistry over three different atmosphere in India. Rain samples were collected during the entire period of monsoon (June-October) in the year of 2013 over Kolkata (22.6 (°) N, 89.4 (°) E), a mega city with typical urban atmosphere; Falta (22.3 (°) N, 88.1 (°) E), a rural atmosphere near eastern coast of Bay of Bengal and Darjeeling (27.01 (°) N, 88.15 (°) E), a high altitude (2200 m asl)hill station over eastern Himalaya in India. The major focus of the study is to investigate the composition of various types of aerosol ionic components scavenged and its effect on the acidity and how it differs between these three distinctly different atmospheres. The results showed that the sea-salt components were higher in Falta (140 mueqv/lit) followed by Kolkata (120 mueqv/lit) and minimum in Darjeeling (30 mueqv/lit). Over all the stations, Na (+) and Cl (-) showed strong correlations indicating common marine source. The marine air masses originated from Bay of Bengal (BoB) were found to significantly enrich sea-salt particles over Falta, the nearest station from BoB and having least effect on Darjeeling, the farthest station from BoB. Dust and anthropogenic aerosols particles were significantly higher over Kolkata compared to other two stations. Dust particles were found to scavenge more in the initial phase of monsoon and it gradually decreased as the monsoon progressed. The average pH of rain water over Kolkata was 6.0 indicating alkaline in nature. pH over Falta was 5.2 indicating slightly acidic in nature and the most important fact is that pH over Darjeeling was 4.6 indicating highly acidic in nature. It was found that Ca (2+) , Mg (2+) and NH _{4} (+) neutralized the acidity of rain water over all the stations with the maximum neutralizing factor for Ca (2+) . However, NH _{4} (+) played important role over Darjeeling in neutralizing rain water acidity. The major reason for high acidity of rain water was not due to high

  2. An investigation of the effects of simulated acid rain and elevated ozone on the physiology of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) seedlings and mature trees

    SciTech Connect

    Momen, B.

    1993-12-31

    This study investigated the combined effects of simulated acid rain and ozone on foliar water relations, carbon and nitrogen contents, gas exchange, and respiration of ponderosa pine seedlings and mature trees grown in the field at the USDA Forest Service Tree Improvement Center in Chico, California. Acid rain levels (pH 5.1 and 3) were applied weekly on foliage only, from January to April, 1992. Plants were exposed to ozone levels (ambient and twice ambient) during the day only, from August to December, 1990, and from September to November, 1992. Results suggested that elevated ozone, particularly in combination with strong acid, caused osmotic adjustment that may benefit plants during drought. The observed effects of pollutants are similar to the reported effects of drought on plant water relations. Elevated ozone decreased foliar nitrogen content and thus increased the C:N ratio, particularly in seedlings. Stomatal conductance was not affected by pollutants but net photosynthesis was decreased by elevated ozone, especially in mature trees. The greater sensitivity of net photosynthesis of mature trees to elevated ozone was contrary to all other plant characteristics investigated. Elevated ozone increased seedling respiration. Under controlled, temperature, light, and vapor pressure deficit conditions, net photosynthesis responded positively to increases in plant age, light intensity, and rain pH, but negatively to increases in tissue age, heat, and ozone concentration. Overall results indicated that acid rain and elevated ozone declined the carbon pool of ponderosa pine due to increased respiration and decreased net photosynthesis. Pollutant effects were more profound in mid-summer when ozone concentrations were highest. On many occasions the effects of acid rain and ozone levels interacted. Seedlings were more sensitive to pollutants than mature trees.

  3. Acid rain damage to carbonate stone: a quantitative assessment based on the aqueous geochemistry of rainfall runoff from stone

    USGS Publications Warehouse

    Reddy, M.M.

    1988-01-01

    An onsite experimental procedure was used to identify and quantify acid rain damage to carbonate stone, based on the change in rain runoff chemical composition. Onsite data obtained during the summer and fall of 1984 at three locations in the northeastern United States indicate that carbonate stone surface recession is related to acid deposition. -from Author

  4. Learning about Acid Rain: A Teacher's Guide for Grades 6 through 8. EPA 430-F-08-002

    ERIC Educational Resources Information Center

    US Environmental Protection Agency, 2008

    2008-01-01

    Acid rain is a complex environmental problem which affects the United States and many other countries around the world. The United States Environmental Protection Agency (EPA) was established in 1970 to address environmental issues, such as acid rain. Through its programs, EPA works to protect human health and the environment in the United States…

  5. Effects of simulated acid rain on the allelopathic potential of invasive weed Wedelia trilobata

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Acid rain continues to pose a major threat to natural ecosystems in rapidly-developing industrialized regions such as southern China. Despite the significant environmental impact of this phenomenon, relatively little is known concerning its effects on important aspects of ecosystem dynamics such as ...

  6. The Influence of a Collaborative Learning Environment on Primary Students' Conceptions about Acid Rain.

    ERIC Educational Resources Information Center

    Marinopoulos, Dimitrios; Stavridou, Heleni

    2002-01-01

    Investigates primary students' conceptions of acid rain formation and its consequences to people and the environment before and after a 10-hour constructivist teaching intervention. Reports improvement in conceptions of physical and chemical phenomena among the experimental group participants. (Contains 23 references.) (Author/YDS)

  7. Chemistry For Kids: Pre-Chemistry Acid Rain Activities for Kids.

    ERIC Educational Resources Information Center

    Barrow, Lloyd H.

    1985-01-01

    Presents two activities on acid rain for students in intermediate grades. Materials needed and procedures used are included. Also describes "chemical magic" shows performed by high school students for sixth-grade students in seven elementary schools in Altus, Oklahoma. (JN)

  8. Analysis of the strengths and weaknesses of acid rain electronic data reports

    SciTech Connect

    Schott, J.

    1997-12-31

    Entergy Corporation is a Phase II utility with a fossil generation base composed primarily of natural gas and low sulfur coal. This paper presents an analysis of a large Phase II utility`s continuous emissions monitoring data reported to EPA under Title IV Acid Rain. Electric utilities currently report hourly emissions of NO{sub x}, SO{sub 2}, CO{sub 2}, fuel use, and generation through electronic data reports to EPA. This paper describes strengths and weaknesses of the data reported to EPA as determined through an analysis of 1995 data. Emissions reported by this company under acid rain for SO{sub 2} and NO{sub x} are very different from emissions reported to state agencies for annual emission inventory purposes in past years and will represent a significant break with historic trends. A comparison of emissions has been made of 1995 emissions reported under Electronic Data Reports to the emissions that would have been reported using emission factors and fuel data in past years. In addition, the paper examines the impacts of 40 CFR Part 75 Acid Rain requirements such as missing data substitution and monitor bias adjustments. Measurement system errors including stack flow measurement and false NO{sub x}Lb/MMBtu readings at very low loads are discussed. This paper describes the implications for public policy, compliance, emissions inventories, and business decisions of Part 75 acid rain monitoring and reporting requirements.

  9. Environmental Policy-Making and Their Impacts in the Case of Acid Rain Abatement.

    ERIC Educational Resources Information Center

    Boehmer-Christiansen, Sonja

    1992-01-01

    Great Britain and Germany accepted European Community acid rain reduction directives. Discusses the differences in the amount of reduction required from each country, the strategies adopted to attain those reductions, and the levels of emission reductions already achieved.(52 references) (MDH)

  10. A Fresh Look at the Benefits and Costs of the US Acid Rain Program

    EPA Science Inventory

    The US Acid Rain Program (Title IV of the 1990 Clean Air Act Amendments) has achieved substantial reductions in emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) from power plants in the United States. We compare new estimates of the benefits and costs of Title IV to th...

  11. The Fugitive Literature of Acid Rain: Making Use of Nonconventional Information Sources in a Vertical File.

    ERIC Educational Resources Information Center

    Lovenburg, Susan L.; Stoss, Frederick W.

    1988-01-01

    Discusses the advantages of vertical file collections for nonconventional literature, and describes the classification scheme used for fugitive literature by the Acid Rain Information Clearinghouse at the Center for Environmental Information. An annotated list of organizations and examples of titles they offer is provided. (8 notes with…

  12. Student Teacher Understanding of the Greenhouse Effect, Ozone Layer Depletion, and Acid Rain.

    ERIC Educational Resources Information Center

    Dove, Jane

    1996-01-01

    Describes the results of a survey designed to ascertain details of student teachers' knowledge and misconceptions about the greenhouse effect, acid rain, and ozone layer depletion. Results indicate familiarity with the issues but little understanding of the concepts involved and many commonly held misconceptions. (JRH)

  13. Acid rain compliance and coordination of state and federal utility regulation

    SciTech Connect

    Nordhaus, R.R.

    1993-07-01

    The Clean Air Act Amendments of 1990 (CAAA) impose new controls on emissions by electric utilities of the two major precursors of acid rain: sulfur dioxide and oxides of nitrogen. Utilities, and the utility holding company systems and power pools of which they are members, will be subject to extensive and costly compliance obligations under the new stature. Most of these utilities, utility systems, and power pools are regulated by more than one utility regulatory authority. Utility regulators will need to coordinate their policies for ratemaking and for review of acid rain compliance strategies if least-cost solutions are to be implemented without imposing on rate payers and utility shareholders the costs and risks of inconsistent regulatory determinations. This article outlines the scope of the coordination problem and spells out possible approaches that utility regulators may take in dealing with it. Topics covered include the following: the 1990 Clean Air Act Amendments; acid rain (SO2); acid rain (NOx); costs of compliance; implications for utility regulation - federal and state utility regulatory framework; potential jurisdictional conflicts under existing state/federal utility regulatory scheme - single utility, holding companies, power pools; Utility regulatory issues under the 1990 amendments - planning conflicts, operational conflicts; methods for dealing with potential jurisdictional conflicts; coordination mechanisms - informal consultation, rulemaking,coordination of adjudicatory proceedings, FERC rate filings.

  14. pH [Measure of Acidity].

    ERIC Educational Resources Information Center

    Henderson, Paula

    This autoinstructional program deals with the study of the pH of given substances by using litmus and hydrion papers. It is a learning activity directed toward low achievers involved in the study of biology at the secondary school level. The time suggested for the unit is 25-30 minutes (plus additional time for further pH testing). The equipment…

  15. The politics of markets: The acid rain control policy in the 1990 Clean Air Act amendments

    SciTech Connect

    Kete, N.

    1993-01-01

    This thesis is a review and critique of the development of the acid rain control policy codified as Title IV of the Clean Air Act. The amendments include provisions to address acid rain-air pollution that has been transformed and transported over long distances. Title IV also embodies the first large scale adoption of market principles and economic incentives in the cause of environmental protection. The acid rain control amendments are being hailed as a break with past environmental protection practice and are being offered as a model for further regulatory reform. The thesis looks at the roots of the acid rain policy and considers the set of legal, social, and economic relations embedded in the policy which define the nature of its legal controls over pollution and its inverse, environmental quality. It explores whether the creation of the emissions allowance trading system changes the social relationships that prevailed under the pre-amended Clean Air Act. It responds to and rebuts the concerns of some critics that the policy represents an alienation of the public's right to clean air. A review of the acid rain policymaking process provides a recent and concrete example of the two central concerns inherent in public policy: the making of decisions that establish institutional arrangements, or structures, that both constrain and liberate individual action at the operational level; and the search for the boundary between autonomous behavior and collective decision making. The policy responds to regulatory reform recommendations concerned with improving the effectiveness, accountability, and cost-effectiveness of environmental protection. As a model for future policymaking, the policy goes beyond and encompasses more than the welfare economics ideal of static economic efficiency and the [open quotes]free market environmentalism[close quotes] emphasis on private property and common law.

  16. Protective effect of Mn(III)-desferrioxamine B upon oxidative stress caused by ozone and acid rain in the Brazilian soybean cultivar Glycine max "Sambaiba".

    PubMed

    Esposito, Jéssica Bordotti Nobre; Esposito, Breno Pannia; Azevedo, Ricardo Antunes; Cruz, Luciano Soares; da Silva, Luzimar Campos; de Souza, Silvia Ribeiro

    2015-04-01

    This study aimed to investigate the effects of the Mn complex (Mn(III)-desferrioxamine B (MnDFB)) on oxidative stress in the Brazilian soybean cultivar Glycine max "Sambaiba" following exposure to ozone and acid rain. We determined the suitable dose of MnDFB to apply to G. max seedlings using a dose-response curve. The highest superoxide dismutase (SOD) activity and Mn content in leaves were found upon the application of 8 μM MnDFB. Thus, G. max seedlings pretreated with 8 μM MnDFB were individually exposed to ozone and acid rain simulated. Pretreatment with MnDFB reduced lipid peroxidation upon ozone exposure and increased SOD activity in leaves; it did not alter the metal content in any part of the plant. Conversely, following acid rain exposure, neither the metal content in leaves nor SOD enzyme activity were directly affected by MnDFB, unlike pH. Our findings demonstrated that exogenous MnDFB application before ozone exposure may modulate the MnSOD, Cu/ZnSOD, and FeSOD activities to combat the ROS excess in the cell. Here, we demonstrated that the applied dose of MnDFB enhances antioxidative defenses in soybean following exposure to acid rain and especially to ozone.

  17. Spatial characterization of acid rain stress in Canadian Shield Lakes

    NASA Technical Reports Server (NTRS)

    Tanis, F. J.; Marshall, E. M.

    1989-01-01

    The lake acidification in Northern Ontario was investigated using LANDSAT TM to sense lake volume reflectance and also to provide important vegetation and terrain characteristics. The purpose of this project was to determine the ability of LANDSAT to assess water quality characteristics associated with lake acidification. Results demonstrate that a remote sensor can discriminate lake clarity based upon reflection. The basic hypothesis is that seasonal and multi-year changes in lake optical transparency are indicative of sensitivity to acidic deposition. In many acid-sensitive lakes optical transparency is controlled by the amount of dissolved organic carbon present. Seasonal changes in the optical transparency of lakes can potentially provide an indication of the stress due to acid deposition and loading.

  18. Photosynthesis and growth response of red spruce and loblolly pine to soil-applied lead and simulated acid rain. [Picea rubens; Pinus taeda

    SciTech Connect

    Seiler, J.R.; Paganelli, D.J.

    1987-09-01

    Soils from red spruce (Picea rubens Sarg.) and loblolly pine (Pinus taeda L.) stands were amended with either 0, 150, 300, 600 or 1200 mg/kg Pb as PbCl/sub 2/. Six-month-old spruce and six-week-old pine seedlings were planted in their respective native soils and treated for 19 weeks with simulated rain of either pH 4.5 or 3.0. Rain was applied directly to the soil at a rate of 1.5 cm per week. Net photosynthesis, height, and needle, shoot, and root dry weights were measured at the completion of the experiment. In both soils, pH decreased and nitrate concentration increased with the application of a simulated rain solution of pH 3.0. Despite these changes in soil chemistry, simulated rain pH had no significant effect on the growth of either species. Red spruce photosynthesis was 35% higher; however, at a pH of 3.0. Loblolly pine photosynthesis was not affected by solution pH. Growth and photosynthesis of red spruce were inhibited even at the 150 mg/kg Pb level, with additional Pb resulting in increasing inhibition. Growth of loblolly pine seedlings was less sensitive to Pb, and decreased only at the higher concentrations. Loblolly pine photosynthesis exhibited no decline even at the highest Pb level. These results suggest that both red spruce and loblolly pine are more sensitive to soil Pb than to acid precipitation. In addition, loblolly pine appears to be more tolerant of Pb than red spruce, when both species are grown in their respective native soils.

  19. Acid rain effects on aluminum mobilization clarified by inclusion of strong organic acids

    USGS Publications Warehouse

    Lawrence, G.B.; Sutherland, J.W.; Boylen, C.W.; Nierzwicki-Bauer, S. W.; Momen, B.; Baldigo, Barry P.; Simonin, H.A.

    2007-01-01

    Assessments of acidic deposition effects on aquatic ecosystems have often been hindered by complications from naturally occurring organic acidity. Measurements of pH and ANCG, the most commonly used indicators of chemical effects, can be substantially influenced by the presence of organic acids. Relationships between pH and inorganic Al, which is toxic to many forms of aquatic biota, are also altered by organic acids. However, when inorganic Al concentrations are plotted against ANC (the sum of Ca2+, Mg 2+, Na+, and K+, minus SO42-, NO3-, and Cl-), a distinct threshold for Al mobilization becomes apparent. If the concentration of strong organic anions is included as a negative component of ANC, the threshold occurs at an ANC value of approximately zero, the value expected from theoretical charge balance constraints. This adjusted ANC is termed the base-cation surplus. The threshold relationship between the base-cation surplus and Al was shown with data from approximately 200 streams in the Adirondack region of New York, during periods with low and high dissolved organic carbon concentrations, and for an additional stream from the Catskill region of New York. These results indicate that (1) strong organic anions can contribute to the mobilization of inorganic Al in combination with SO42- and NO 3-, and (2) the presence of inorganic Al in surface waters is an unambiguous indication of acidic deposition effects. ?? 2007 American Chemical Society.

  20. Acid rain effects on aluminum mobilization clarified by inclusion of strong organic acids.

    PubMed

    Lawrence, G B; Sutherland, J W; Boylen, C W; Nierzwicki-Bauer, S W; Momen, B; Baldigo, B P; Simonin, H A

    2007-01-01

    Assessments of acidic deposition effects on aquatic ecosystems have often been hindered by complications from naturally occurring organic acidity. Measurements of pH and ANCG, the most commonly used indicators of chemical effects, can be substantially influenced by the presence of organic acids. Relationships between pH and inorganic Al, which is toxic to many forms of aquatic biota, are also altered by organic acids. However, when inorganic Al concentrations are plotted against ANC (the sum of Ca2+, Mg2+, Na+, and K+, minus S042-, N03-, and Cl-), a distinct threshold for Al mobilization becomes apparent. If the concentration of strong organic anions is included as a negative component of ANC, the threshold occurs at an ANC value of approximately zero, the value expected from theoretical charge balance constraints. This adjusted ANC is termed the base-cation surplus. The threshold relationship between the base-cation surplus and Al was shown with data from approximately 200 streams in the Adirondack region of New York, during periods with low and high dissolved organic carbon concentrations, and for an additional stream from the Catskill region of New York. These results indicate that (1) strong organic anions can contribute to the mobilization of inorganic Al in combination with SO42- and N03-, and (2) the presence of inorganic Al in surface waters is an unambiguous indication of acidic deposition effects.

  1. Effect of artificial acid rain and SO2 on characteristics of delayed light emission.

    PubMed

    Wang, Chenglong; Xing, Da; Zeng, Lizhang; Ding, Chunfeng; Chen, Qun

    2005-01-01

    The structure and function of chloroplast in plant leaves can be affected by acid rain and air pollution. The photosystem II in a plant is considered the primary site where light-induced delayed light emission (DLE) is produced. With the lamina of zijinghua (Bauhinia variegata L.) and soybean (Glycine max (L.) Merr.) as testing models, we studied the effects of artificial acid rain and SO2 on characteristics of DLE by using a home-made weak luminescence detection system. The results show that the changes in DLE intensity of green plants can reflect the changes in chloroplast intactness and function. With proper calibration, DLE may provide an alternative means of evaluating environmental acid stress on plants. The changes in DLE intensity may provide a new approach for the detection of environmental pollution and its impact on the ecosystem.

  2. Enhancing tolerance of rice (Oryza sativa) to simulated acid rain by exogenous abscisic acid.

    PubMed

    Wu, Xi; Liang, Chanjuan

    2017-02-01

    Abscisic acid (ABA) regulates much important plant physiological and biochemical processes and induces tolerance to different stresses. Here, we studied the regulation of exogenous ABA on adaptation of rice seedlings to simulated acid rain (SAR) stress by measuring biomass dry weight, stomatal conductance, net photosynthesis rate, nutrient elements, and endogenous hormones. The application of 10 μM ABA alleviated the SAR-induced inhibition on growth, stomatal conductance, net photosynthesis rate, and decreases in contents of nutrient (K, Mg, N, and P) and hormone (auxin, gibberellins, and zeatin). Moreover, 10 μM ABA could stimulate the Ca content as signaling molecules under SAR stress. Contrarily, the application of 100 μM ABA aggravated the SAR-induced inhibition on growth, stomatal conductance, net photosynthesis rate, and contents of nutrient and hormone. The results got after a 5-day recovery (without SAR) show that exogenous 10 μM ABA can promote self-restoration process in rice whereas 100 μM ABA hindered the restoration by increasing deficiency of nutrients and disturbing the balance of hormones. These results confirmed that exogenous ABA at proper concentration could enhance the tolerance of rice to SAR stress.

  3. Acid rain: commentary on controversial issues and observations on the role of fuel burning

    SciTech Connect

    Szabo, M.F.; Esposito, M.P.; Spaite, P.W.

    1982-03-01

    Even though much information has been accumulated on the subject of acid precipitation, lack of knowledge in certain technical areas precludes an adequate understanding of (1) how serious the acid precipitation problem really is and (2) what effect controlling sources of acid precipitation precursors would have in reducing acidification. It is nevertheless possible to draw some broad conclusions regarding the problem and to ascertain the direction that the required further work should take. This report presents the results of an investigation of various issues associated with acid rain. The following topics are addressed: occurrence of acid precipitation; effects of acid precipitation; sources of acid precipitation; transport, transformation, and deposition of acid pollutants; and fuel trend analysis. Recommendations for further research are included. (DMC)

  4. Reduction of dehydroascorbic acid at low pH.

    PubMed

    Wechtersbach, Luka; Cigić, Blaz

    2007-08-01

    Ascorbic acid and dehydroascorbic acid are unstable in aqueous solution in the presence of copper and iron ions, causing problems in the routine analysis of vitamin C. Their stability can be improved by lowering the pH below 2, preferably with metaphosphoric acid. Dehydroascorbic acid, an oxidised form of vitamin C, gives a relatively low response on the majority of chromatographic detectors, and is therefore routinely determined as the increase of ascorbic acid formed after reduction. The reduction step is routinely performed at a pH that is suboptimal for the stability of both forms. In this paper, the reduction of dehydroascorbic acid with tris-[2-carboxyethyl] phosphine (TCEP) at pH below 2 is evaluated. Dehydroascorbic acid is fully reduced with TCEP in metaphosphoric acid in less than 20 min, and yields of ascorbic acid are the same as at higher pH. TCEP and ascorbic acid formed by reduction, are more stable in metaphosphoric acid than in acetate or citrate buffers at pH 5, in the presence of redox active copper ions. The simple experimental procedure and low probability of artefacts are major benefits of this method, over those currently applied in a routine assay of vitamin C, performed on large number of samples.

  5. Combined effects of lanthanum ion and acid rain on growth, photosynthesis and chloroplast ultrastructure in soybean seedlings.

    PubMed

    Wen, Kejia; Liang, Chanjuan; Wang, Lihong; Hu, Gang; Zhou, Qing

    2011-07-01

    Rare earth elements (REEs) have been accumulated in the agricultural environment. Acid rain is a serious environmental issue. In the present work, the effects of lanthanum ion (La(3+)) and acid rain on the growth, photosynthesis and chloroplast ultrastructure in soybean seedlings were investigated using the gas exchange measurements system, chlorophyll fluorometer, transmission electron microscopy and some biochemical techniques. It was found that although the growth and photosynthesis of soybean seedlings treated with the low concentration of La(3+) was improved, the growth and photosynthesis of soybean seedlings were obviously inhibited in the combined treatment with the low concentration of La(3+) and acid rain. At the same time, the chloroplast ultrastructure in the cell of soybean seedlings was destroyed. Under the combined treatment with the high concentration of La(3+) and acid rain, the chloroplast ultrastructure in the cell of soybean seedlings was seriously destroyed, and the growth and of photosynthesis were greatly decreased compared with those of the control, the single treatment with the high concentration of La(3+) and the single treatment with acid rain, respectively. The degree of decrease and destruction on chloroplast ultrastructure depended on the increases in the concentration of La(3+) and acid rain (H(+)). In conclusion, the combined pollution of La(3+) and acid rain obviously destroyed the chloroplast ultrastructure of cell and aggravated the harmful effect of the single La(3+) and acid rain on soybean seedlings. As a new combined pollutant, the harmful effect of REEs ions and acid rain on plant should be paid attention to.

  6. Acid rain: a review of the phenomenon in the EEC and Europe

    SciTech Connect

    Not Available

    1983-01-01

    The environmental damage that may be attributable to acid rain is examined in detail. Its effect on trees, crops and other terrestrial flora and fauna, fish and other aquatic flora and fauna, buildings, and health are discussed. The sources of acid pollutant emissions, as well as how they are thought to affect environmental change are described. Likely future trends in emissions and types of acid pollutants and their derivatives are also discussed. The need for further research into the problem is stressed and the costs and benefits of alternative emission control strategies are evaluated.

  7. Acid Rain Effects on Adirondack Streams - Results from the 2003-05 Western Adirondack Stream Survey (the WASS Project)

    USGS Publications Warehouse

    Lawrence, Gregory B.; Roy, Karen M.; Baldigo, Barry P.; Simonin, Howard A.; Passy, Sophia I.; Bode, Robert W.; Capone, Susan B.

    2009-01-01

    Traditionally lakes have been the focus of acid rain assessments in the Adirondack region of New York. However, there is a growing recognition of the importance of streams as environmental indicators. Streams, like lakes, also provide important aquatic habitat, but streams more closely reflect acid rain effects on soils and forests and are more prone to acidification than lakes. Therefore, a large-scale assessment of streams was undertaken in the drainage basins of the Oswegatchie and Black Rivers; an area of 4,585 km2 in the western Adirondack region where acid rain levels tend to be highest in New York State.

  8. Effect of Simulated Acid Rain on Bursaphelenchus xylophilus Infection of Pine Seedlings

    PubMed Central

    Bolla, R. I.; Fitzsimmons, K.

    1988-01-01

    White, Scots, and Austrian 3-year-old pine seedlings were treated with conditions simulating acid rain and inoculated with the white pine specific pathotype of Bursaphelenchus xylophilus, VPSt-1. Oleoresin concentration increased slightly and carbohydrate concentration decreased in all seedlings treated with simulated acid rain (SAR). The changes were significantly increased after inoculation of SAR-treated white and Scots pine seedlings with VPSt-1. Wilting was delayed and nematode reproduction decreased in SAR-treated white pine seedlings inoculated with VPSt-1. SAR-treated Austrian pine seedlings were resistant to VPSt-1, but SAR-treated Scots pine seedlings lost tolerance to VPSt-1 and wilted 50-60 days after inoculation. PMID:19290259

  9. Regulatory impact analysis of the proposed acid-rain implementation regulations

    SciTech Connect

    Not Available

    1991-09-16

    This regulatory impact analysis (RIA) was developed in response to Executive Order (EO) 12291, which requires Federal Agencies to assess the costs, benefits, and impacts of all 'major' regulations. In compliance with EO 12291, this RIA assesses costs, benefits and impacts for the important provisions of Title IV. EPA divided its analysis of the Acid Rain Program into two parts. First, EPA analyzed the effects of the statute in the absence of any implementation regulations. In the second part of the analysis, EPA examined a 'regulatory' case that included both the SO2 reductions and the implementation regulations. By comparing costs under the regulatory case to those under the absent regulations case, EPA was able to isolate the incremental savings provided by the regulations. At the same time, by combining the two parts of the analysis, EPA was able to show the total costs imposed by the Acid Rain Program (the statute and the regulations) as a whole.

  10. The Quality Assurance Manual and EPA`s acid rain data quality

    SciTech Connect

    Bloomer, B.J.; Winkler, J.P.

    1995-12-31

    November 15, 1990 saw the passage of the Clean Air Act Amendments of 1990. Within this law was the requirements for all electric utility units greater than 25 megawatts of generated electrical capacity to monitor SO{sub 2}, NO{sub x}, CO{sub 2}, opacity, and volumetric flow of the stack gases. This paper summarizes the Acid Rain Program`s approach to Continuous Emissions Monitoring Systems (CEMS) Quality Control and Quality Assurance requirements and their use in the market based pollution control program of Title IV of the Clean Air Act Amendments of 1990. This paper attempts to present the perspective of the authors as to what is important for excellent monitoring system availability and ensuring accurate data acquisition. Emphasis is placed upon the Quality Assurance Manual required by the Acid Rain Regulations for affected unit`s to maintain and follow.

  11. Electric Utility Phase I Acid Rain Compliance Strategies for the Clean Air Act Amendments of 1990

    EIA Publications

    1994-01-01

    The Acid Rain Program is divided into two time periods; Phase I, from 1995 through 1999, and Phase II, starting in 2000. Phase I mostly affects power plants that are the largest sources of SO2 and NOx . Phase II affects virtually all electric power producers, including utilities and nonutilities. This report is a study of the effects of compliance with Phase I regulations on the costs and operations of electric utilities, but does not address any Phase II impacts.

  12. Acid rain, air pollution, and tree growth in southeastern New York

    USGS Publications Warehouse

    Puckett, L.J.

    1982-01-01

    Whether dendroecological analyses could be used to detect changes in the relationship of tree growth to climate that might have resulted from chronic exposure to components of the acid rain-air pollution complex was determined. Tree-ring indices of white pine (Pinus strobus L.), eastern hemlock (Tsuga canadensis (L.) Cart.), pitch pine (Pinus rigida Mill.), and chestnut oak (Quercus prinus L.) were regressed against orthogonally transformed values of temperature and precipitation in order to derive a response-function relationship. Results of the regression analyses for three time periods, 1901–1920, 1926–1945, and 1954–1973 suggest that the relationship of tree growth to climate has been altered. Statistical tests of the temperature and precipitation data suggest that this change was nonclimatic. Temporally, the shift in growth response appears to correspond with the suspected increase in acid rain and air pollution in the Shawangunk Mountain area of southeastern New York in the early 1950's. This change could be the result of physiological stress induced by components of the acid rain-air pollution complex, causing climatic conditions to be more limiting to tree growth.

  13. Acid rain, air pollution, and tree growth in southeastern New York

    SciTech Connect

    Puckett, L.J.

    1982-07-01

    Whether dendroecological analyses could be used to detect changes in the relationship of tree growth to climate that might have resulted from chronic exposure to components of the acid rain-air pollution complex was determined. Tree-ring indices of white pine (Pinus strobus L.), eastern hemlock (Tsuga canadensis (L.) Carr.), pitch pine (Pinus rigida Mill.), and chestnut oak (Quercus prinus L.) were regressed against orthogonally transformed values of temperature and precipitation in order to derive a response-function relationship. Results of the regression analyses for three time periods, 1901-1920, 1926-1945, and 1954-1973 suggest that the relationship of tree growth to climate has been altered. Statistical tests of the temperature and precipitation data suggest that this change was nonclimatic. Temporally, the shift in growth response appears to correspond with the suspected increase in acid rain and air pollution in the Shawangunk Mountain area of southeastern New York in the early 1950's. This change could be the result of physiological stress induced by components of the acid rain-air pollution complex, causing climatic conditions to be more limiting to tree growth.

  14. Research on the acid rain under the short-term environment control measures of the Youth Olympic Games

    NASA Astrophysics Data System (ADS)

    Li, S.; Qing, W.; Chen, Y.; Peng, Y.

    2015-12-01

    Northern China emits the most part of acid pollution of the whole nation but turns out to be in a light acid precipitation extent. Research shows that it is the carbonate particles from dust that neutralize the acid in the rainfall. Construction in southern China becomes more and more active so that alkaline dusts from construction are receiving an increasing attention. Nanjing hosts the Youth Olympic Games in 2015 and implements a strict plan to control the emission of construction dust. Thus, The Youth Olympic Games provides a good opportunity to analyze the neutralization of alkaline dusts emitted from construction in Nanjing. Experiment is conducted by collecting the total of rainfall events from June to September in 2015, besides, TSP (total suspended particles) before and after each rainfall events is collected due to find the collaboration with rainfall. Ca2+,Mg2+,K+,Na+,Sr2+,F-,Cl-,SO42-,NO3- concentrations in rain water and water soluble fraction of TSP are analyzed using ICP-OES and ICS in Nanjing University. Results showed that Ca2+and SO42- makes the major part of total ions, indicating the fact that Nanjing is suffering from a severe acid rainfall and alkaline dusts which mainly consist of Ca2+ neutralize a large number of acid particles. pH of rainfall has a good correlation with the flux of TSP. pH of rainfall keeps falling as the YOG plan starts and picking up after the YOG, which indicates that the declination of artificial alkaline dust in TSP reduces the neutralization on the acid rainfall.

  15. Effects of simulated acid rain on soil respiration and its components in a subtropical mixed conifer and broadleaf forest in southern China.

    PubMed

    Liang, Guohua; Hui, Dafeng; Wu, Xiaoying; Wu, Jianping; Liu, Juxiu; Zhou, Guoyi; Zhang, Deqiang

    2016-02-01

    Soil respiration is a major pathway in the global carbon cycle and its response to environmental changes is an increasing concern. Here we explored how total soil respiration (RT) and its components respond to elevated acid rain in a mixed conifer and broadleaf forest, one of the major forest types in southern China. RT was measured twice a month in the first year under four treatment levels of simulated acid rain (SAR: CK, the local lake water, pH 4.7; T1, water pH 4.0; T2, water pH 3.25; and T3, water pH 2.5), and in the second year, RT, litter-free soil respiration (RS), and litter respiration (RL) were measured simultaneously. The results indicated that the mean rate of RT was 2.84 ± 0.20 μmol CO2 m(-2) s(-1) in the CK plots, and RS and RL contributed 60.7% and 39.3% to RT, respectively. SAR marginally reduced (P = 0.08) RT in the first year, but significantly reduced RT and its two components in the second year (P < 0.05). The negative effects were correlated with the decrease in soil microbial biomass and fine root biomass due to soil acidification under the SAR. The temperature coefficients (Q10) of RT and its two components generally decreased with increasing levels of the SAR, but only the decrease of RT and RL was significant (P < 0.05). In addition, the contribution of RL to RT decreased significantly under the SAR, indicating that RL was more sensitive to the SAR than RS. In the context of elevated acid rain, the decline trend of RT in the forests in southern China appears to be attributable to the decline of soil respiration in the litter layer.

  16. Judicial recourse against foreign air polluters: a case study of acid rain in Europe

    SciTech Connect

    Pallemaerts, M.

    1985-01-01

    Many European nations suffering acid damage caused primarily by pollution originating outside of their borders have had little success in persuading polluters to voluntarily reduce emissions. The author explores the opportunities for private litigation by victims against foreign sources of long-range transboundary air pollution. Such private actions would establish the illegality of transboundary air pollution and draw public attention to the magnitude of the damage as well as generate compensation. Recent actions in Norway and Britain suggest that is is procrastination to insist upon more research into the cause and effects of acid rain.

  17. Effect of organic/inorganic compounds on the enzymes in soil under acid rain stress.

    PubMed

    Liu, Guang-shen; Xu, Dong-mei; Wang, Li-ming; Li, Ke-bin; Liu, Wei-ping

    2004-01-01

    The main effects of pollutions including acid rain, Cu2+, atrazine and their combined products on the activities of urease, invertin, acid phosphatase and catalase were studied by means of orthogonal test. The results showed that H+ and Cu2+ had significant influence on the activities of four enzymes and the ability of their inhibiting followed the order: H+ > Cu2+. Al3+ and atrazine only had litter effects on the activity of urease and phosphatase, respectively. Furthermore, interaction analysis revealed that Cu2+ -H+ affected on the activity of acid phosphatase significantly and antagonism on invertin and urease, Cu2+ -atrazine only exhibited the synergism on the activity of acid phosphatase. But atrazine-H+ had non-interaction within the investigated concentration range. Among four enzymes, acid phosphatase was the most sensitive one to the contaminations.

  18. Different responses of two Mosla species to potassium limitation in relation to acid rain deposition.

    PubMed

    Wang, Meng; Gu, Bao-jing; Ge, Ying; Liu, Zhen; Jiang, De-an; Chang, Scott X; Chang, Jie

    2009-08-01

    The increasingly serious problem of acid rain is leading to increased potassium (K) loss from soils, and in our field investigation, we found that even congenerically relative Mosla species show different tolerance to K-deficiency. A hydroponic study was conducted on the growth of two Mosla species and their morphological, physiological and stoichiometric traits in response to limited (0.35 mmol K/L), normal (3.25 mmol K/L) and excessive (6.50 mmol K/L) K concentrations. Mosla hangchowensis is an endangered plant, whereas Mosla dianthera a widespread weed. In the case of M. hangchowensis, in comparison with normal K concentration, K-limitation induced a significant reduction in net photosynthetic rate (P(n)), soluble protein content, and superoxide dismutase (SOD) activity, but an increase in malondialdehyde (MDA) concentration. However, leaf mass ratio (LMR) and root mass ratio (RMR) were changed little by K-limitation. In contrast, for M. dianthera, K-limitation had little effect on P(n), soluble protein content, SOD activity, and MDA concentration, but increased LMR and RMR. Critical values of N (nitrogen):K and K:P (phosphorus) ratios in the shoots indicated that limitation in acquiring K occurred under K-limited conditions for M. hangchowensis but not for M. dianthera. We found that low K content in natural habitats was a restrictive factor in the growth and distribution of M. hangchowensis, and soil K-deficiency caused by acid rain worsened the situation of M. hangchowensis, while M. dianthera could well acclimate to the increasing K-deficiency. We suggest that controlling the acid rain and applying K fertilizers may be an effective way to rescue the endangered M. hangchowensis.

  19. Acid rain program offers free-market incentives, portends future regulation

    SciTech Connect

    Cozza, A.; Faulkner, K.F. )

    1993-05-01

    The burning of fossil fuels, particularly coal and oil, results in emissions of sulfur dioxide (SO[sub 2]) and nitrogen oxide (NOx). Such emissions and their by-products damage ecosystems and man-made materials, and threaten human health. In 1985, 23 million tons of SO[sub 2] and 19 million tons of NOx were emitted from US sources. Nearly 70% of the SO[sub 2] and almost 40% of the NOx emissions originated from electric utilities. Title IV of the CAA Amendments requires EPA to establish an acid rain program designed to reduce SO[sub 2] and NOx emissions from electric utility plants.

  20. Toward integrating environmental and economic education: lessons from the US acid rain program

    SciTech Connect

    Michael J. Ellerbrock; Ann M. Regn

    2004-04-15

    This field report presents an actual case study which illustrates that the natural and social sciences, in this case ecology and economics, can and should be integrated in environmental education and the formulation of public policy. After outlining basic economic approaches for addressing environmental problems, it focuses on the process and principles involved in the marketable permit system established by the 1990 Clean Air Act Amendments for preventing acid rain by reducing emissions of sulfur and nitrous oxides in the United States. The system has generated significant reductions in emissions and projected costs of compliance.

  1. Acid rain and tree physiology: some hypotheses for observed changes in forest productivity

    SciTech Connect

    McLaughlin, S.B.

    1983-01-01

    The experimental evidence for several principal physiological pathways of influence of acid rain and associated pollutants on forest growth processes was examined. This was accomplished by examining experimental evidence from a variety of sources which suggest likely mechanisms of response. The following mechanisms were examined: (1) altered plant-water relations, (2) altered availability of nutrients, (3) direct effects on growth and physiological processes, and (4) indirect effects on resistance to biotic and abiotic stresses. Some characteristics of recent forest declines were examined to evaluate consistencies of response patterns with physiological mechanisms. 8 references, 4 figures, 8 tables. (MF)

  2. Acid rain in China. Rapid industrialization has put citizens and ecosystems at risk

    SciTech Connect

    Thorjoern Larssen; Espen Lydersen; Dagang Tang

    2006-01-15

    Acid rain emerged as an important environmental problem in China in the late 1970s. Many years of record economic growth have been accompanied by increased energy demand, greater coal combustion, and larger emissions of pollutants. As a result of significant emissions and subsequent deposition of sulfur, widespread acid rain is observed in southern and southwestern China. In fact, the deposition of sulfur is in some places higher than what was reported from the 'black triangle' in central Europe in the early 1980s. In addition, nitrogen is emitted from agriculture, power production, and a rapidly increasing number of cars. As a result, considerable deposition of pollutants occurs in forested areas previously thought to be pristine. Little is known about the effects of acid deposition on terrestrial and aquatic ecosystems in China. This article presents the current situation and what to expect in the future, largely on the basis of results from a five-year Chinese-Norwegian cooperative project. In the years ahead, new environmental challenges must be expected if proper countermeasures are not put into place. 31 refs., 4 figs.

  3. Emissions of the natural acidic substance in the acid rain region: Dimethyl sulfide and hydrogen sulfide in the region of Xiamen, China

    SciTech Connect

    Yubao Wang; Miaoqin Lu

    1996-12-31

    The global anthropogenic emissions of sulfur, mainly SO2, are relatively well studied for most of the industrialized world, and relatively little is known to date about natural sulfur emission sources, such as, coastal waters and wetland. The most important atmospheric sulfur compounds originating from biogeochemical sources are DMS and H{sub 2}S. Previous studies suggest that biogenic DMS is mainly emitted from oceanic phytoplankton species. The global emission of sulfur by this process was estimated to be 40 Tg S/year. Major sources of biogenic H{sub 2}S in the atmosphere are believed to be bacterial sulfate reduction in anoxic soils and degradation of organic matter. The mentioned reduced sulfur compounds are partially oxidation in the troposphere to SO{sub 2} and further to sulfur acid, another strong acid produced from DMS oxidation is methane sulphonic acid (CH{sub 3}S(O{sub 2})OH). These compounds are strong acid and will influence the pH of precipitation and will be the important impact in acid rain phenomena.

  4. The role of EPA`s Acid Rain Division in the Ozone Transport Commission`s NOx budget program

    SciTech Connect

    Schary, C.; Culligan, K.

    1997-12-31

    The Ozone Transport Commission`s (OTC) Nitrogen Oxides (NO{sub x}) Budget Program will implement the emissions reduction goal of the 1994 Memorandum of Understanding between its twelve member states and the District of Columbia. The program will achieve its significant NO{sub x} reductions from electric utilities and industrial boilers using a {open_quotes}cap-and-trade{close_quotes} approach modeled after the US Environmental Protection Agency`s sulfur dioxide emissions trading under the Acid Rain Program. The similarity of the two programs has led to the development of an important partnership between the OTC states and EPA`s Acid Rain Division, Over the past two years, Acid Rain Program staff have shared their technical expertise and assisted extensively in the development of the program`s rules. Leveraging the investment EPA made in the systems used to run the Acid Rain Program, the OTC states have asked the Acid Rain Division to administer the data systems for them, and together are working to expand its existing Emissions Tracking System and to modify a clone of the sulfur dioxide Allowance Tracking System, to fulfill the unique requirements of the NO{sub x} Budget Program. This partnership is an important example of the new type of cooperation and sharing of expertise and resources that should develop between EPA and states as they launch multi-state programs to address regional pollution problems that defy a single-state solution.

  5. The Acid Rain Program`s 1995 annual reconciliation: Design and experience

    SciTech Connect

    Schary, C.; Shellabarger, M.; Smith, K.

    1997-12-31

    The completion of the first year of compliance under the US Environmental Protection Agency`s Acid Rain Program provides an excellent opportunity to analyze its results for early indications on the effectiveness of the program`s design. Established under Title IV of the 1990 Clean Air Act Amendments, the implementation of the program`s two-phased approach to reducing sulfur dioxide emissions from electric utilities proved to be more complex and more costly than its supporters anticipated. An unanticipated complication was the difficult task of accounting for shifts in electric generation from Phase I sources to those not affected until Phase II. This paper examines the results of the 1995 reconciliation process and analyzes the value of the two-phased approach in accomplishing the stated goals of the Acid Rain Program: to achieve significant emissions reductions at the lowest possible cost to the affected sources, and to society in general. The paper concludes that Phase I implementation costs were disproportionately large, imposed sizeable costs on Phase II sources as well, who had to install monitors early but did not receive any of its benefits - additional allowances. A better design might have been to include all sources in both phases while maintaining the two-step reduction schedule.

  6. Acid-rain publications by the US Fish and Wildlife Service, 1979-1989. Final report

    SciTech Connect

    Villella, R.F.

    1989-08-01

    This report is an annotated bibliography of acid-rain and related air-quality publications authored or co-authored by the U.S. Fish and Wildlife Service employees or that have been supported by Service funding. The bibliography covers 10 years of research from 1979 to 1989. Research projects have covered the effects of acidity on water chemistry, aquatic invertebrates, amphibians, fish, and waterfowl. Specific projects have addressed important fish species such as rainbow trout, brook trout, Atlantic salmon, and striped bass. In addition to lake and stream studies, wetland and some terrestrial habitat work has also been conducted. Also included in the report is research on the ecological effects of liming surface waters and surrounding watersheds.

  7. Acid rain publications by the U.S. Fish and Wildlife Service, 1979-1989

    USGS Publications Warehouse

    Villella, Rita F.

    1989-01-01

    Pollution of aquatic and terrestrial ecosystems has been a concern to society since the burning of fossil fuels began in the industrial revolution. In the past decade or so, this concern has been heightened by evidence that chemical transformation in the atmosphere of combustion by-products and subsequent long-range transport can cause environmental damage in remote areas. The extent of this damage and the rates of ecological recovery were largely unknown. "Acid rain" became the environmental issue of the 1980's. To address the increasing concerns of the public, in 1980 the Federal government initiated a 10-year interagency research program to develop information that could be used by the President and the Congress in making decisions for emission controls. The U.S. Fish and Wildlife Service has been an active participant in acid precipitation research. The Service provided support to a number of scientific conferences and forums, including the Action Seminar on Acid Precipitation held in Toronto, Canada, in 1979, an international symposium on Acidic Precipitation and Fishery Impacts in Northeastern North America in 1981, and a symposium on Acidic Precipitation and Atmospheric Deposition: A Western Perspective in 1982. These meetings as well as the growing involvement with the government's National Acidic Precipitation Assessment Program placed the Service in the lead in research on the biological effects of acidic deposition. Research projects have encompassed water chemistry, aquatic invertebrates, amphibians, fish, and waterfowl. Water quality surveys have been conducted to help determine the extent of acid precipitation effects in the northeast, Middle Atlantic, and Rocky Mountain regions. In addition to lake and stream studies, research in wetland and some terrestrial habitats has also been conducted. Specific projects have addressed important sport species such as brook trout (Salvelinus fontinalis), Atlantic salmon (Salmo salar), and striped bass (Morone

  8. Fog/cloud and rain chemistry in northern coastal California

    SciTech Connect

    Bicknell, S.H.; Lemcke, S.

    1987-07-01

    Fog, clouds and rain were sampled for 2 years at Redwood National Park (RNP) and one year at Arcata and Oakland. Fog and cloud water samples were more acidic and contained higher concentrations of Ca, Mg, K, Na, NH4, SO4, NO3 and Cl, than rain samples at all sites. Cloud/fog water and rain sample chemistry was not different for RNP and Arcata; but Oakland samples were significantly more acid and had higher concentrations of all elements. RNP and Arcata cloud/fog samples were more acid and contained higher elemental concentrations than expected under pristine conditions. Average pH's were: RNP cloud/fog - 4.12, RNP rain - 4.63, Arcata cloud/fog - 4.00, Arcata rain - 4.66, Oakland cloud/fog - 3.87, Oakland rain - 4.37.

  9. Report of the Acid Rain Peer Review Panel. Final report, July 1984

    SciTech Connect

    Not Available

    1984-01-01

    The panel was chartered to perform three tasks: (1) a peer review of the scientific basis relating to acid deposition in Eastern North America performed by three US-Canadian work groups; (2) provide further research and monitoring recommendations to reduce uncertainties in the scientific and technical knowledge regarding acid deposition; and (3) assess uncertainties in scientific and technical information on which the work groups recommendations were based. The panel views the acid rain problem as follows. Acid deposition belongs to a socially very important class of problems that only appear to be precisely soluble by a straightforward sum of existing technological and legislative fixes. This is deceptive. Rather, this class of problems is not permanently solved in a closed fashion, but must be treated progressively. As knowledge steadily increases, actions are taken which appear most effective and economical in the light of increasing understanding. There exist large uncertainties in every aspect of acid deposition - emission, transport, transformation, and eventual deposition, interaction with the biosphere, and economic consequences. Nevertheless, when all the converging partial indicators are considered, it becomes clear that acid deposition is a problem for which solutions should be sought now, and further remedial steps taken.

  10. Effects of simulated acid rain on soil and soil solution chemistry in a monsoon evergreen broad-leaved forest in southern China.

    PubMed

    Qiu, Qingyan; Wu, Jianping; Liang, Guohua; Liu, Juxiu; Chu, Guowei; Zhou, Guoyi; Zhang, Deqiang

    2015-05-01

    Acid rain is an environmental problem of increasing concern in China. In this study, a laboratory leaching column experiment with acid forest soil was set up to investigate the responses of soil and soil solution chemistry to simulated acid rain (SAR). Five pH levels of SAR were set: 2.5, 3.0, 3.5, 4.0, and 4.5 (as a control, CK). The results showed that soil acidification would occur when the pH of SAR was ≤3.5. The concentrations of NO₃(-)and Ca(2+) in the soil increased significantly when the pH of SAR fell 3.5. The concentration of SO₄(2-) in the soil increased significantly when the pH of SAR was <4.0. The effects of SAR on soil solution chemistry became increasingly apparent as the experiment proceeded (except for Na(+) and dissolved organic carbon (DOC)). The net exports of NO₃(-), SO₄(2-), Mg(2+), and Ca(2+) increased about 42-86% under pH 2.5 treatment as compared to CK. The Ca(2+) was sensitive to SAR, and the soil could release Ca(2+) through mineral weathering to mitigate soil acidification. The concentration of exchangeable Al(3+) in the soil increased with increasing the acidity of SAR. The releases of soluble Al and Fe were SAR pH dependent, and their net exports under pH 2.5 treatment were 19.6 and 5.5 times, respectively, higher than that under CK. The net export of DOC was reduced by 12-29% under SAR treatments as compared to CK. Our results indicate the chemical constituents in the soil are more sensitive to SAR than those in the soil solution, and the effects of SAR on soil solution chemistry depend not only on the intensity of SAR but also on the duration of SAR addition. The soil and soil solution chemistry in this region may not be affected by current precipitation (pH≈4.5) in short term, but the soil and soil leachate chemistry may change dramatically if the pH of precipitation were below 3.5 and 3.0, respectively.

  11. Effects of simulated acid rain, EDTA, or their combination, on migration and chemical fraction distribution of extraneous metals in Ferrosol.

    PubMed

    Wen, Fang; Hou, Hong; Yao, Na; Yan, Zengguang; Bai, Liping; Li, Fasheng

    2013-01-01

    A laboratory repacked soil-leaching column experiment was conducted to study the effects of simulated acid rain or EDTA by themselves or in combination, on migration and chemical speciation distribution of Pb and its alternative rare metals including Ag, Bi, In, Sb, and Sn. Experimental results demonstrate that leaching with simulated acid rain promoted the migration of Bi, In and Pb, and their migration reached down to 8 cm in the soil profile, no enhancement of Sb, Ag or Sn migration was observed. Addition of EDTA significantly enhanced the migration of all six metals, especially Bi, In and Pb. The migration of metals was in the order Pb>Bi>In>Sb>Sn>Ag. The individual and combined effects of acid rain and EDTA increased the environmental risk of metals, by increasing the soluble content of metals in soil solutions and the relative distribution of the exchangeable fraction. Leaching risks of Bi, In and Pb were higher than other three metals.

  12. Organic acids make Escherichia coli more resistant to pulsed electric fields at acid pH.

    PubMed

    Somolinos, M; García, D; Mañas, P; Condón, S; Pagán, R

    2010-01-01

    Stationary growth phase cells of Escherichiacoli were more pulsed electric fields (PEF) resistant in citrate-phosphate McIlvaine buffer at pH 4.0 than at pH 7.0. The greater PEF resistance was also confirmed in fruit juices of similar acid pH. In this work we studied whether the higher PEF resistance of E. coli at acid pH was due to the low pH itself or to the interaction of the components of the treatment medium with the cells. The protective effect on E. coli cells was due to the presence of organic acids such as citric, acetic, lactic or malic at pH 4.0. The protective effect of citric acid at pH 4.0 depended on its concentration. A linear relationship was observed between the Log(10) of the citric acid concentration and the degree of inactivation. Organic acids contained in laboratory treatment media (citrate-phosphate buffer) or in fruit juices did not sensitize E. coli cells to PEF but, on the contrary, they induced a protective effect that made E. coli cells more resistant at pH 4.0 than at neutral pH. This work could be useful for improving food preservation by PEF technology and it contributes to the knowledge of the mechanism of microbial inactivation by PEF.

  13. Predicting recovery from acid rain using the micro-spatial heterogeneity of soil columns downhill the infiltration zone of beech stemflow: introduction of a hypothesis.

    PubMed

    Berger, Torsten W; Muras, Alexander

    Release of stored sulfur may delay the recovery of soil pH from Acid Rain. It is hypothesized that analyzing the micro-spatial heterogeneity of soil columns downhill of a beech stem enables predictions of soil recovery as a function of historic acid loads and time. We demonstrated in a very simplified approach, how these two different factors may be untangled from each other using synthetic data. Thereafter, we evaluated the stated hypothesis based upon chemical soil data with increasing distance from the stem of beech trees. It is predicted that the top soil will recover from acid deposition, as already recorded in the infiltration zone of stemflow near the base of the stem. However, in the between trees areas and especially in deeper soil horizons recovery may be highly delayed.

  14. Physiological responses of root-less epiphytic plants to acid rain.

    PubMed

    Kováčik, Jozef; Klejdus, Bořivoj; Bačkor, Martin; Stork, František; Hedbavny, Josef

    2011-03-01

    Selected physiological responses of Tillandsia albida (Bromeliaceae) and two lichens (Hypogymnia physodes and Xanthoria parietina) exposed to simulated acid rain (AR) over 3 months were studied. Pigments were depressed in all species being affected the most in Tillandsia. Amounts of hydrogen peroxide and superoxide were elevated and soluble proteins decreased only in AR-exposed Hypogymnia. Free amino acids were slightly affected among species and only glutamate sharply decreased in AR-exposed Xanthoria. Slight increase in soluble phenols but decrease in flavonoids in almost all species suggests that the latter are not essential for tolerance to AR. Almost all phenolic acids in Tillandsia leaves decreased in response to AR and activities of selected enzymes (phenylalanine ammonia-lyase, polyphenol oxidase, ascorbate- and guaiacol-peroxidase) were enhanced by AR. In lichens, considerable increase in metabolites (physodalic acid, atranorin and parietin) in response to AR was found but amount of ergosterol was unchanged. Macronutrients (K, Ca, Mg) decreased more pronouncedly in comparison with micronutrients in all species. Xanthoria showed higher tolerance in comparison with Hypogymnia, suggesting that could be useful for long-term biomonitoring.

  15. Acid rain mitigation experiment shifts a forested watershed from a net sink to a net source of nitrogen

    PubMed Central

    Rosi-Marshall, Emma J.; Bernhardt, Emily S.; Buso, Donald C.; Driscoll, Charles T.; Likens, Gene E.

    2016-01-01

    Decades of acid rain have acidified forest soils and freshwaters throughout montane forests of the northeastern United States; the resulting loss of soil base cations is hypothesized to be responsible for limiting rates of forest growth throughout the region. In 1999, an experiment was conducted that reversed the long-term trend of soil base cation depletion and tested the hypothesis that calcium limits forest growth in acidified soils. Researchers added 1,189 kg Ca2+ ha−1 as the pelletized mineral wollastonite (CaSiO3) to a 12-ha forested watershed within the Hubbard Brook Experimental Forest in the White Mountains of New Hampshire. Significant increases in the pH and acid-neutralizing capacity of soils and streamwater resulted, and the predicted increase in forest growth occurred. An unanticipated consequence of this acidification mitigation experiment began to emerge a decade later, with marked increases in dissolved inorganic nitrogen (DIN) exports in streamwater from the treated watershed. By 2013, 30-times greater DIN was exported from this base-treated watershed than from adjacent reference watersheds, and DIN exports resulting from this experiment match or exceed earlier reports of inorganic N losses after severe ice-storm damage within the study watershed. The discovery that CaSiO3 enrichment can convert a watershed from a sink to a source of N suggests that numerous potential mechanisms drive watershed N dynamics and provides new insights into the influence of acid deposition mitigation strategies for both carbon cycling and watershed N export. PMID:27335456

  16. Acid rain mitigation experiment shifts a forested watershed from a net sink to a net source of nitrogen.

    PubMed

    Rosi-Marshall, Emma J; Bernhardt, Emily S; Buso, Donald C; Driscoll, Charles T; Likens, Gene E

    2016-07-05

    Decades of acid rain have acidified forest soils and freshwaters throughout montane forests of the northeastern United States; the resulting loss of soil base cations is hypothesized to be responsible for limiting rates of forest growth throughout the region. In 1999, an experiment was conducted that reversed the long-term trend of soil base cation depletion and tested the hypothesis that calcium limits forest growth in acidified soils. Researchers added 1,189 kg Ca(2+) ha(-1) as the pelletized mineral wollastonite (CaSiO3) to a 12-ha forested watershed within the Hubbard Brook Experimental Forest in the White Mountains of New Hampshire. Significant increases in the pH and acid-neutralizing capacity of soils and streamwater resulted, and the predicted increase in forest growth occurred. An unanticipated consequence of this acidification mitigation experiment began to emerge a decade later, with marked increases in dissolved inorganic nitrogen (DIN) exports in streamwater from the treated watershed. By 2013, 30-times greater DIN was exported from this base-treated watershed than from adjacent reference watersheds, and DIN exports resulting from this experiment match or exceed earlier reports of inorganic N losses after severe ice-storm damage within the study watershed. The discovery that CaSiO3 enrichment can convert a watershed from a sink to a source of N suggests that numerous potential mechanisms drive watershed N dynamics and provides new insights into the influence of acid deposition mitigation strategies for both carbon cycling and watershed N export.

  17. Implications of the Clean Air Act acid rain title on industrial boilers

    SciTech Connect

    Maibodi, M. )

    1991-11-01

    This paper discusses the impacts of the 1990 Clean Air Act Amendments related to acid rain controls, as they apply to industrial boilers. Emphasis is placed on explaining the Title IV provisions of the Amendments that permit nonutility sources to participate in the SO{sub 2} allowance system. The allowance system, as it pertains to industrial boiler operators, is described, and the opportunities for operators to trade and/or sell SO{sub 2} emission credits is discussed. The paper also reviews flue gas desulfurization system technologies available for industrial boiler operators who may choose to participate in the system. Furnace sorbent injection, advanced silicate process, lime spray drying, dry sorbent injection, and limestone scrubbing are described, including statements of their SO{sub 2} removing capability, commercial status, and costs. Capital costs, levelized costs and cost-effectiveness are presented for these technologies.

  18. Allowance trading activity and state regulatory rulings: Evidence from the US Acid Rain Program

    SciTech Connect

    Bailey, E.M.

    1997-12-31

    The US Acid Rain Program is one of the first, and by far the most extensive, applications of a market based approach to pollution control. From the beginning, there has been concern whether utilities would participate in allowance trading, and whether regulatory activity at the state level would further complicate utilities` decision to trade allowances. This paper finds that public utility commission regulation has encouraged allowance trading activity in states with regulatory rulings, but that allowance trading activity has not been limited to states issuing regulations. Until there is evidence suggesting that significant additional cost savings could have been obtained if additional allowance trading activity had occurred in states without regulations or that utilities in states with regulations are still not taking advantage of all cost saving trading opportunities, this analysis suggests that there is little reason to believe that allowance trading activity is impeded by public utility commission regulations.

  19. Organic acids in cloud water and rainwater at a mountain site in acid rain areas of South China.

    PubMed

    Sun, Xiao; Wang, Yan; Li, Haiyan; Yang, Xueqiao; Sun, Lei; Wang, Xinfeng; Wang, Tao; Wang, Wenxing

    2016-05-01

    To investigate the chemical characteristics of organic acids and to identify their source, cloud water and rainwater samples were collected at Mount Lu, a mountain site located in the acid rain-affected area of south China, from August to September of 2011 and March to May of 2012. The volume-weighted mean (VWM) concentration of organic acids in cloud water was 38.42 μeq/L, ranging from 7.45 to 111.46 μeq/L, contributing to 2.50 % of acidity. In rainwater samples, organic acid concentrations varied from 12.39 to 68.97 μeq/L (VWM of 33.39 μeq/L). Organic acids contributed significant acidity to rainwater, with a value of 17.66 %. Formic acid, acetic acid, and oxalic acid were the most common organic acids in both cloud water and rainwater. Organic acids had an obviously higher concentration in summer than in spring in cloud water, whereas there was much less discrimination in rainwater between the two seasons. The contribution of organic acids to acidity was lower during summer than during spring in both cloud water (2.20 % in summer vs 2.83 % in spring) and rainwater (12.24 % in summer vs 19.89 % in spring). The formic-to-acetic acid ratio (F/A) showed that organic acids were dominated by primary emissions in 71.31 % of the cloud water samples and whole rainwater samples. Positive matrix factorization (PMF) analysis determined four factors as the sources of organic acids in cloud water, including biogenic emissions (61.8 %), anthropogenic emissions (15.28 %), marine emissions (15.07 %) and soil emissions (7.85 %). The findings from this study imply an indispensable role of organic acids in wet deposition, but organic acids may have a limited capacity to increase ecological risks in local environments.

  20. Acidic pH environment induces autophagy in osteoblasts

    PubMed Central

    Zhang, Zhichao; Lai, Qingguo; Li, Yanan; Xu, Chao; Tang, Xiaopeng; Ci, Jiangbo; Sun, Shaolong; Xu, Bingbing; Li, Yan

    2017-01-01

    Osteoblasts (OBs) play an important role in bone fracture healing, yet the extreme adverse microenvironment in fracture sites has a negative impact on the survival of OBs. Therefore, it is important to study how OBs behave in the complex fracture microenvironment. Studies have shown that autophagy plays a pivotal role in maintaining cellular homeostasis and defending the cell against adverse microenvironments. In this study we found the induction of autophagy in OBs at femoral bone fracture sites, which may be a result of ischemia, oxidative stress and hypoxia within the local area. At fracture sites a low pH environment also developed. Until now it has been unclear whether the induction of autophagy in osteoblasts is triggered by the acidic pH environment. Therefore, we cultured OBs in vitro in media of different pH values, and found both autophagy and apoptosis increased in OBs in acidic conditions. However, when autophagy inhibitor chloroquine (CQ) was used, apoptosis increased significantly compared with that without CQ. Thus indicating that inhibition of autophagy may promote apoptosis in OBs in an acidic environment, which may provide a new therapeutic strategy to decrease cell apoptosis in OBs through the use of drugs that modulate the autophagic state. PMID:28382973

  1. The U.S. Acid rain program: Key insights from the design, operation, and assessment of a Cap-and-Trade program

    SciTech Connect

    Napolitano, Sam; Schreifels, Jeremy; Stevens, Gabrielle; Witt, Maggie; LaCount, Melanie; Forte, Reynaldo; Smith, Kenon

    2007-08-15

    The authors' 15 years of experience with the Acid Rain Program suggests that for regional or larger-scale air pollution problems, such as acid rain and pollution transport, a well-designed cap-and-trade program can be cost-effective, flexible, and easy to implement with clear benefits that can be sustained into the future. (author)

  2. Bolide impacts, acid rain, and biospheric traumas at the Cretaceous-Tertiary boundary

    NASA Technical Reports Server (NTRS)

    Prinn, Ronald G.; Fegley, Bruce, Jr.

    1987-01-01

    Two plausible projectiles are considered: an ice-rich long-period comet and a much smaller rock-metal asteroid. In the framework of a proposal addressed by Lewis et al. (1982), it is shown that, while the impact projectiles themselves do not shock-heat the atmosphere very extensively, the supersonic plume of water vapor and rock produced on impact does shock the atmosphere up to global scales and the shock is of sufficient intensity to produce abundant nitric oxide. For example, an ice-rich long-period comet with a mass of 1.25 x 10 to the 16th kg and a velocity of 65 km/s striking the earth would produce about 7 x 10 to the 40th molecules NO through shock-heating of the atmosphere by the high-velocity ejecta plume fragments. Specific attention is given to the fraction of the atmosphere shock-heated, the global circulation of the nitrogen oxides, the effects of the ejecta plume water on acid rain (AR) predictions, the effects of AR on continental soils, the relationship between AR production rates and the total amount of acid needed to acidify the surface oceans, and the longevity of the oceanic acidity event and the exhaled CO2 event and their implications for the environment in the first millenia or so after the impact.

  3. Lots of data, how do we use it? Strengths and inaccuracies of utility acid rain electronic data reports

    SciTech Connect

    Schott, J.

    1996-12-31

    Entergy Corporation is a Phase II utility with a fossil generation base composed primarily natural gas and low sulfur coal. This paper presents an analysis of a large Phase II utility`s continuous emissions monitoring data reported to EPA under Title IV Acid Rain. Electric utilities currently report hourly emissions of NOx, SO{sub 2}, CO{sub 2}, fuel use, and generation through electronic data reports to EPA. This paper describes strengths and weaknesses of the data reported to EPA as determined through an analysis of 1995 data. Emissions reported by this company tinder acid rain for SO{sub 2} and NOx are very different from emissions reported to state agencies for annual emission inventory purposes in past years and will represent a significant break with historic trends. A comparison of emissions has been made of 1995 emissions reported under Electronic Data Reports to the emissions that would have been reported using emission factors and fuel data in past years. In addition, the paper examines the impacts of 40 CFR Part 75 Acid Rain requirements such as missing data substitution and monitor bias adjustments. Measurement system errors including stack flow measurement and false NOx Lb/MMBtu readings at very low loads are discussed. This paper describes the implications for public policy, compliance, emissions inventories, and business decisions of Part 75 acid rain monitoring and reporting requirements.

  4. Evaluating Potential Bias in Media Coverage of the Public Debate over Acid Rain and Chlorofluorocarbons in the 1980s

    ERIC Educational Resources Information Center

    Williams, Tiffany Dawn; Moore, Rebecca; Markewitz, Daniel

    2012-01-01

    This study evaluates media coverage of two important environmental issues from the 1980s (acid rain and chlorofluorocarbons), providing historical context for current media coverage analysis. Focusing on popular magazine articles, this study identifies key characteristics of content and presentation. Content-related characteristics are inclusion…

  5. Development and Implementation of a Simple, Engaging Acid Rain Neutralization Experiment and Corresponding Animated Instructional Video for Introductory Chemistry Students

    ERIC Educational Resources Information Center

    Rand, Danielle; Yennie, Craig J.; Lynch, Patrick; Lowry, Gregory; Budarz, James; Zhu, Wenlei; Wang, Li-Qiong

    2016-01-01

    Here we describe an acid rain neutralization laboratory experiment and its corresponding instructional video. This experiment has been developed and implemented for use in the teaching laboratory of a large introductory chemistry course at Brown University. It provides a contextually relevant example to introduce beginner-level students with…

  6. An analysis of chemical composition of different rain types in `Minnan Golden Triangle' region in the southeastern coast of China

    NASA Astrophysics Data System (ADS)

    Yu, Shaocai; Gao, Chentie; Cheng, Zhemian; Cheng, Xiaojian; Cheng, Shuentian; Xiao, Jian; Ye, Wenxian

    The pollutants from anthropogenic activities can affect precipitation composition and subsequently affect aquatic and terrestrial ecosystems. Here, we reported the results from the simultaneous collection and chemical analysis (including F -, Cl -, NO 3-, SO 42-, HCOO -, CH 3COO -, Na +, NH 4+, K +, Ca 2+, Mg 2+, pH) of spring rain, mold rain and typhoon rain during 1990 and 1991 in the region of Xiamen, Quanzhou, Zhangzhou and Tongan, which is called `Minnan Golden Triangle' and is a rapidly growing urban area in the southeastern Coast of China. It was found that the average pHs of spring rain, mold rain and typhoon rain in 1990 in this region were 4.51, 4.93 and 5.14, respectively. Obviously, the spring rain was the most acidic in the three types of rains in this region. The average concentrations of formic and acetic acids in Xiamen mold rain were 5.67 and 2.91 μeq/l, respectively, and the average maximum contribution of organic acids to free acidity was in the range of 2.8% to 100% (average 66.3%). The regression equations between acidity and ions showed that SO 42, NO 3-, NH 4+ and organic acids (formic and acetic) made the major contribution to the precipitation acidity in this region. The chemical characteristics of different precipitation types in this region indicated that spring rain had the character of continental origin, but the mold rain and typhoon rain had more effects from ocean. Since spring rain, mold rain, and typhoon rain were caused by precipitation cloud approaching to this region from different directions and had different acidity, and the average pH of cloud rainwater on the mountain site was 4.90, it is suggested that acid rain in this region might be mainly caused by long-range transport of pollutants from the southern Chinese mainland, and the local pollution sources were less as significant.

  7. Effects of simulated acidic rain on yields of Raphanus sativus, Lactuca sativa, Triticum aestivum and Medicago sativa

    SciTech Connect

    Evans, L.S.; Gmur, N.F.; Mancini, D.

    1982-01-01

    Experiments were performed to determine effects of simulated acidic rain on radishes (Raphanus sativus), wheat(Triticum aestivum) and alfalfa (Medicago sativa) grown under greenhouse conditions. Experimental designs allowed the detection of statistically significant differences among means that differed by less than 10%. These results suggest that the efficiency of radish foliage in increasing; root mass decreases with increased rainfall acidity since only foliage was exposed to the treatments.

  8. Desorption of 137Cs from Brachythecium mildeanum moss using acid solutions with pH 4.60-6.50

    NASA Astrophysics Data System (ADS)

    Čučulović, Ana; Veselinović, Dragan

    2015-12-01

    The desorption of 137Cs from the moss Brachythecium mildeanum (Schimp.) was performed using the following solutions: H2SO4 ( I), HNO3 ( II), H2SO4 + HNO3 ( III) with pH values of 4.60, 5.15, and 5.75, respectively, as well as distilled water (D) with pH 6.50. After five successive desorptions, each lasting 24 h, 20.5-37.6% 137Cs was desorbed from the moss using these solutions, while 30.7% of the starting content was desorbed using distilled water. The first desorption removed the highest percent of the original content of 137Cs in the moss (11.3-18.4%). This was determined by measuring 137Cs activity. If the current results are compared with those obtained earlier it may be concluded that 137Cs desorption from mosses is not species-dependent. The obtained results indicate the necessity of investigating the influence of acid rain, or rather, of H+ ions, on desorption of other ions from biological systems, i.e., the role of H+ ions in spreading other polluting compounds and thus producing secondary environmental pollution. From the results of this study it follows that acid rain will lead, through H+ ion action, to a similar increasing pollution of fallout waters with other ionic compounds which may not be present in the water before the contact with the plants and thus enable the pollution spreading. In the investigated system, the replacement of H+ ions from acid rains by more dangerous radioactive ions occured, increasing the concentration of the radioactive ions in the water, which demonstrates that the same process takes place in fallout water.

  9. Comparative proteomic analysis of proteins in response to simulated acid rain in Arabidopsis.

    PubMed

    Liu, Ting-Wu; Fu, Bin; Niu, Li; Chen, Juan; Wang, Wen-Hua; He, Jun-Xian; Pei, Zhen-Ming; Zheng, Hai-Lei

    2011-05-06

    A proteomic study using 2-D gel electrophoresis and MALDI-TOF MS was performed to characterize the responses of Arabidopsis thaliana plants to simulated acid rain (SiAR) stress, which is a global environmental problem and has become a serious issue in China in recent years. The emphasis of the present study was to investigate the overall protein expression changes when exposed to SiAR. Out of over 1000 protein spots reproducibly resolved, 50 of them changed their abundance by at least 2-fold. Analysis of protein expression patterns revealed that a set of proteins associated with energy production, metabolism, cell rescue, cell defense and protein folding, etc., could play important roles in mediating plant response to SiAR. In addition to this, some proteins involved in stress responses and jasmonic acid pathway are also involved in plant response to SiAR. More interestingly, the expression of several ubiquitination-related proteins changed dramatically after 32-h SiAR treatment, suggesting that they may act as a molecular marker for the injury phenotype caused by SiAR. Based on our results, we proposed a schematic model to explain the mechanisms associated with the systematic response of Arabidopsis plants to SiAR.

  10. Combined Effects of Lanthanum (III) and Acid Rain on Antioxidant Enzyme System in Soybean Roots.

    PubMed

    Zhang, Xuanbo; Du, Yuping; Wang, Lihong; Zhou, Qing; Huang, Xiaohua; Sun, Zhaoguo

    2015-01-01

    Rare earth element pollution (REEs) and acid rain (AR) pollution simultaneously occur in many regions, which resulted in a new environmental issue, the combined pollution of REEs and AR. The effects of the combined pollution on the antioxidant enzyme system of plant roots have not been reported. Here, the combined effects of lanthanum ion (La3+), one type of REE, and AR on the antioxidant enzyme system of soybean roots were investigated. In the combined treatment of La3+ (0.08 mM) and AR, the cell membrane permeability and the peroxidation of cell membrane lipid of soybean roots increased, and the superoxide dismutase, catalase, peroxidase and reduced ascorbic acid served as scavengers of reactive oxygen species. In other combined treatments of La3+ (0.40 mM, 1.20 mM) and AR, the membrane permeability, malonyldialdehyde content, superoxide dismutase activity, peroxidase activity and reduced ascorbic acid content increased, while the catalase activity decreased. The increased superoxide dismutase activity, peroxidase activity and reduced ascorbic acid content were inadequate to scavenge the excess hydrogen peroxide and superoxide, leading to the damage of the cell membrane, which was aggravated with the increase in the concentration of La3+ and the level of AR. The deleterious effects of the combined treatment of La3+ and AR were stronger than those of the single treatment of La3+ or AR. Moreover, the activity of antioxidant enzyme system in the combined treatment group was affected directly and indirectly by mineral element content in soybean plants.

  11. Combined Effects of Lanthanum (III) and Acid Rain on Antioxidant Enzyme System in Soybean Roots

    PubMed Central

    Zhang, Xuanbo; Du, Yuping; Wang, Lihong; Zhou, Qing; Huang, Xiaohua; Sun, Zhaoguo

    2015-01-01

    Rare earth element pollution (REEs) and acid rain (AR) pollution simultaneously occur in many regions, which resulted in a new environmental issue, the combined pollution of REEs and AR. The effects of the combined pollution on the antioxidant enzyme system of plant roots have not been reported. Here, the combined effects of lanthanum ion (La3+), one type of REE, and AR on the antioxidant enzyme system of soybean roots were investigated. In the combined treatment of La3+ (0.08 mM) and AR, the cell membrane permeability and the peroxidation of cell membrane lipid of soybean roots increased, and the superoxide dismutase, catalase, peroxidase and reduced ascorbic acid served as scavengers of reactive oxygen species. In other combined treatments of La3+ (0.40 mM, 1.20 mM) and AR, the membrane permeability, malonyldialdehyde content, superoxide dismutase activity, peroxidase activity and reduced ascorbic acid content increased, while the catalase activity decreased. The increased superoxide dismutase activity, peroxidase activity and reduced ascorbic acid content were inadequate to scavenge the excess hydrogen peroxide and superoxide, leading to the damage of the cell membrane, which was aggravated with the increase in the concentration of La3+ and the level of AR. The deleterious effects of the combined treatment of La3+ and AR were stronger than those of the single treatment of La3+ or AR. Moreover, the activity of antioxidant enzyme system in the combined treatment group was affected directly and indirectly by mineral element content in soybean plants. PMID:26230263

  12. Enhanced acid rain and atmospheric deposition of nitrogen, sulfur and heavy metals in Northern China

    NASA Astrophysics Data System (ADS)

    Pan, Y.; Wang, Y.

    2013-12-01

    Atmospheric deposition is known to be important mechanism reducing air pollution. In response to the growing concern on the potential effects of the deposited material entering terrestrial and aquatic environments as well as their subsequent health effects, since 2007 we have established a 10-site monitoring network in Northern China, where particularly susceptible to severe air pollution. Wet and dry deposition was collected using an automatic wet-dry sampler. The presentation will focus on the new results of atmospheric deposition flux for a number of chemical species, such as nutrients (e.g. nitrogen and phosphorus), acidic matters (e.g. sulfur and proton), heavy metals and Polycyclic Aromatic Hydrocarbons, etc. This is to our knowledge the first detailed element budget study in the atmosphere across Northern China. We find that: (1) Over the 3 year period, 26% of precipitation events in the target area were more acid than pH 5.60 and these acidic events occurred in summer and autumn. The annual volume-weighted mean (VWM) pH value of precipitation was lower than 5.60 at most sites, which indicated the acidification of precipitation was not optimistic. The primary ions in precipitation were NH4+, Ca2+, SO42- and NO3-, with 10-sites-average concentrations of 221, 216, 216 and 80 μeq L-1, respectively. The ratio of SO42- to NO3- was 2.7; suggesting SO42- was the dominant acid component. (2) The deposited particles were neutral in general and the pH value increased from rural area to industrial and coastal sites. It is not surprising to note that the annual VWM pH value of precipitation was higher than 5.60 at three urban sites (Beijing and Tianjin mega cities) and one coastal site near the Bohai Bay, considering the fact that high buffer capacity of alkaline component, gas NH3 and mineral aerosols, at these sites compared to other places. (3) The 10-sites annual total deposition amounts for sulfur and nitrogen compounds were 60 and 65 kg N/S ha-1 yr-1

  13. State acid rain programs: Progress & issues in Phase II SO{sub 2}, NO{sub x}, & opt-ins permitting

    SciTech Connect

    Miller, R.L.

    1997-12-31

    Almost all States have adopted acid rain permitting regulations as part of their title V operating permits programs, and will be adopting acid rain NO{sub x} regulations in the near future. Phase II affected sources achieved a high degree of compliance with the statutory requirement to submit initial Phase II acid rain permit applications by January 1, 1996. The Acid Rain Opt-in Program is being implemented, sources are submitting opt-in permit applications to EPA and permits have been issued. Phase II NO{sub x} regulations are being promulgated, affected sources are submitting NO{sub x} early election plans to EPA, and Phase II NO{sub x} guidance for States will be distributed in 1997. Forty CFR part 72 (the acid rain program permits regulation) is being revised primarily to streamline the permitting process for State and local permitting authorities and to improve integration with 40 CFR part 70 (the state operating permits program regulation). Acid rain permitting demands will increase for States over the next 3 years, current State adherence to statutory and regulatory acid rain permitting requirements for Phase II affected sources remains high.

  14. The role of calcium in improving photosynthesis and related physiological and biochemical attributes of spring wheat subjected to simulated acid rain.

    PubMed

    Dolatabadian, Aria; Sanavy, Seyed Ali Mohammad Modarres; Gholamhoseini, Majid; Joghan, Aydin Khodaei; Majdi, Mohammad; Kashkooli, Arman Beyraghdar

    2013-04-01

    The response of photosynthesis parameters, catalase, superoxide dismutase and peroxidase activity, malondialdehyde, proline, chlorophyll, yield and yield components to foliar application of calcium and simulated acid rain in wheat were investigated. Foliar treatment of calcium led to significant increases in the photosynthesis rate, transpiration rate, stomatal conductance, proline, chlorophyll, yield and yield components in plants subjected to acid rain. Antioxidant enzyme activity and lipid peroxidation in the wheat leaves decreased because of calcium foliar application. Calcium hindered degradation of the rubisco subunits under acid rain treatment compared with water-treated plants. Results suggest that acid rain induces the production of free radicals resulting in lipid peroxidation of the cell membrane so that significant increase in antioxidant enzyme activity was observed. In addition, photosynthetic parameters i.e. photosynthesis rate, transpiration rate and stomatal conductance were drastically suppressed by acid rain. The cellular damage caused by free radicals might be reduced or prevented by a protective metabolism including antioxidative enzymes and calcium. We report that foliar application of calcium before acid rain may ameliorate the adverse effects of acid rain in wheat plants.

  15. A transcriptomic study reveals differentially expressed genes and pathways respond to simulated acid rain in Arabidopsis thaliana.

    PubMed

    Liu, Ting-Wu; Niu, Li; Fu, Bin; Chen, Juan; Wu, Fei-Hua; Chen, Juan; Wang, Wen-Hua; Hu, Wen-Jun; He, Jun-Xian; Zheng, Hai-Lei

    2013-01-01

    Acid rain, as a worldwide environmental issue, can cause serious damage to plants. In this study, we provided the first case study on the systematic responses of arabidopsis (Arabidopsis thaliana (L.) Heynh.) to simulated acid rain (SiAR) by transcriptome approach. Transcriptomic analysis revealed that the expression of a set of genes related to primary metabolisms, including nitrogen, sulfur, amino acid, photosynthesis, and reactive oxygen species metabolism, were altered under SiAR. In addition, transport and signal transduction related pathways, especially calcium-related signaling pathways, were found to play important roles in the response of arabidopsis to SiAR stress. Further, we compared our data set with previously published data sets on arabidopsis transcriptome subjected to various stresses, including wound, salt, light, heavy metal, karrikin, temperature, osmosis, etc. The results showed that many genes were overlapped in several stresses, suggesting that plant response to SiAR is a complex process, which may require the participation of multiple defense-signaling pathways. The results of this study will help us gain further insights into the response mechanisms of plants to acid rain stress.

  16. Spatial characterization of acid rain stress in Canadian Shield lakes. Progress report, 1 August 1985-1 February 1986

    SciTech Connect

    Tanis, F.J.

    1986-01-01

    The acidification of lake waters from airborne pollutants is of continental proportions both in North America and Europe. A major concern of the acid rain problem is the cumulative ecosystem damage to lakes and forest. The number of lakes affected in northeastern United States and on the Canadian Shield is though to be enormous. The principle objective is to examine how seasonal changes in lake water transparency are related to annual acidic load. Further, the relationship between variations in lake acidification and ecophysical units is being examined. Finally, the utility of Thematic Mapper (TM) based observations to measure seasonal changes in the optical transparency in acid lakes is being investigated.

  17. Carryover effects of acid rain and ozone on the physiology of multiple flushes of loblolly pine seedlings. [Pinus taeda L

    SciTech Connect

    Sasek, T.W.; Richardson, C.J.; Fendick, E.A.; Bevington, S.R. ); Kress, L.W. )

    1991-09-01

    The effects of acid rain and ozone exposure on loblolly pine (Pinus taeda L.) seedlings in the Piedmont of North Carolina were assessed over two exposure seasons (1987-1988). Direct effects and carryover effects of long-term exposure on the photosynthetic potential and photopigment concentrations of different needle age-classes were studied. Three half-sib families were grown in open-top field chambers and exposed two acid rain treatments and five ozone exposures delivered in proportion to ambient concentrations in a complete factorial design. Ozone significantly affected photosynthesis but there were no statistically significant effects of acid rain nor any ozone {times} acid rain interactions. In 1987, photosynthesis of the 1987 first-flush progressively diverged among the ozone treatments except between charcoal-filtered and nonfiltered air (NF). At the end of the first season, photosynthesis was reduced 24% at 1.5{times} compared to CF and more than 80% at 2.25{times} and 3.0{times}. Chlorophyll and carotenoid concentrations were similarly reduced at elevated ozone exposures. In 1988, photosynthesis of the 1987 first-flush in the elevated ozone treatments remained lower. Early in the second season, the 1988 first-flush had a 25% to 50% lower photosynthetic potential at 2.25{times} and 3.0{times} compared to CF. This carryover effect on the photosynthetic potential before significant cumulative exposure was progressively smaller in the later 1988 flushes. In the late season flushes in the highest ozone treatments, photosynthesis was significantly higher than in the lower ozone treatments.

  18. Gypsy moth (Lepidoptera: Lymantriidae) consumption and utilization of northern red oak and white oak foliage exposed to simulated acid rain and ozone

    SciTech Connect

    Cannon, W.N. Jr. )

    1993-06-01

    Two-year-old seedlings of white oak, Quercus alba L., and red oak, Q. rubra L., were exposed to ozone (O[sub 3]) fumigations in four continuously stirred tank reactor chambers in the greenhouse for 8 h/d, 3 d/wk for 6 wk. Fumigation treatments were charcoal-filtered air (CFA) and CFA + 0.15 ppm O[sub 3]. Two simulated rain treatments, pH 4.2 and pH 3.0, of-1.25 cm were applied once each week in rain-simulation chambers. Gypsy moth, Lymantria dispar (L.), third instars were allowed to feed on leaf disks from treated seedlings for 24 h. Leaf area consumed, food assimilated, weight gain, and relative growth rate (RGR) were examined. Overall, larvae fed white oak foliage consumed more foliage and gained more weight than those fed red oak foliage. Response to the fumigation and rain treatments was different for each oak species. On white oak foliage, larvae consumed significantly less foliage treated with CFA + pH 3.0 rain, but the lowest RGR occurred with the 0.15 ppm O[sub 3] + pH 4.2 rain treatment. The most food assimilated, greatest weight gain, and highest RGR occurred with the CFA + pH 4.2 rain control. Red oak foliage consumed was equivalent for all treatments, but foliage exposed to CFA + pH 3.0 rain resulted in more food assimilated, greater weight gain, and higher RGR for that species.

  19. Acid rain monitoring in East-Central Florida from 1977 to present

    NASA Technical Reports Server (NTRS)

    Madsen, B. C.; Kheoh, T.; Hinkle, C. R.; Dreschel, T. W.

    1990-01-01

    Rainfall has been collected on the University of Central Florida campus and at the Kennedy Space Center over a 12 year period. The chemical composition has been determined and summarized by monthly, annual periods, and for the entire 12 year period at both locations. The weighted average pH at each site is 4.58; however, annual weighted average pH has been equal to or above the 12 year average during six of the past eight years. Nitrate concentrations have increased slightly during recent years while excess sulfate concentrations have remained below the 12 year weighted average during six of the past seven years. Stepwise regression suggests that sulfate, nitrate, ammonium ion and calcium play major roles in the description of rainwater acidity. Annual acid deposition and annual rainfall have varied from 20 to 50 meg/(m(exp 2) year) and 100 to 180 cm/year, respectively. Sea salt comprises at least 25 percent of the total ionic composition.

  20. Silicon alleviates simulated acid rain stress of Oryza sativa L. seedlings by adjusting physiology activity and mineral nutrients.

    PubMed

    Ju, Shuming; Wang, Liping; Yin, Ningning; Li, Dan; Wang, Yukun; Zhang, Cuiying

    2017-03-16

    Silicon (Si) has been a modulator in plants under abiotic stresses, such as acid rain. To understand how silicon made an effect on rice (Oryza sativa L.) exposed to simulated acid rain (SAR) stress, the growth, physiologic activity, and mineral nutrient content in leaves of rice were investigated. The results showed that combined treatments with Si (1.0, 2.0, or 4.0 mM) and SAR (pH 4.0, 3.0, or 2.0) obviously improved the rice growth compared with the single treatment with SAR. Incorporation of Si into SAR treatment decreased malondialdehyde (MDA) content; increased soluble protein and proline contents; promoted CAT, POD, SOD, and APX activity; and maintained the K, Ca, Mg, Fe, Zn, Cu content balance in leaves of rice seedlings under SAR stress. The moderate concentration of Si (2.0 mM) was better than the low and high concentration of Si (1.0 and 4.0 mM). Therefore, application of Si could be a better strategy for maintaining the crop productivity in acid rain regions.

  1. [Relationships between soil moisture and needle-fall in Masson pine forests in acid rain region of Chongqing, Southwest China].

    PubMed

    Wang, Yi-Hao; Wang, Yan-Hui; Li, Zhen-Hua; Yu, Peng-Tao; Xiong, Wei; Hao, Jia; Duan, Jian

    2012-10-01

    From March 2009 to November 2011, an investigation was conducted on the spatiotemporal variation of soil moisture and its effects on the needle-fall in Masson pine (Pinus massoniana) forests in acid rain region of Chongqing, Southeast China, with the corresponding soil moisture thresholds determined. No matter the annual precipitation was abundant, normal or less than average, the seasonal variation of soil moisture in the forests could be obviously divided into four periods, i.e., sufficient (before May), descending (from June to July), drought (from August to September), and recovering (from October to November). With increasing soil depth, the soil moisture content increased after an initial decrease, but the difference of the soil moisture content among different soil layers decreased with decreasing annual precipitation. The amount of monthly needle-fall in the forests in growth season was significantly correlated with the water storage in root zone (0-60 cm soil layer), especially in the main root zone (20-50 cm soil layer). Soil field capacity (or capillary porosity) and 82% of field capacity (or 80% of capillary porosity) were the main soil moisture thresholds affecting the litter-fall. It was suggested that in acid rain region, Masson pine forest was easily to suffer from water deficit stress, especially in dry-summer period. The water deficit stress, together with already existed acid rain stress, would further threaten the health of the Masson forest.

  2. HCl in rocket exhaust clouds - Atmospheric dispersion, acid aerosol characteristics, and acid rain deposition

    NASA Technical Reports Server (NTRS)

    Pellett, G. L.; Sebacher, D. I.; Bendura, R. J.; Wornom, D. E.

    1983-01-01

    Both measurements and model calculations of the temporal dispersion of peak HCl (g + aq) concentration in Titan III exhaust clouds are found to be well characterized by one-term power-law decay expressions. The respective coefficients and decay exponents, however, are found to vary widely with meteorology. The HCl (g), HCl (g + aq), dewpoint, and temperature-pressure-altitude data for Titan III exhaust clouds are consistent with accurately calculated HCl/H2O vapor-liquid compositions for a model quasi-equilibrated flat surface aqueous aerosol. Some cloud evolution characteristics are also defined. Rapid and extensive condensation of aqueous acid clearly occurs during the first three min of cloud rise. Condensation is found to be intensified by the initial entrainment of relatively moist ambient air from lower levels, that is, from levels below eventual cloud stabilization. It is pointed out that if subsequent dilution air at stabilization altitude is significantly drier, a state of maximum condensation soon occurs, followed by an aerosol evaporation phase.

  3. Analysis of utility acid rain compliance plans: A discussion of issues and methods

    SciTech Connect

    Brick, S.

    1993-07-01

    Utility acid rain compliance plans have begun to roll into public utility commissions around the eastern half of the country. These plans typically represent the combined effort of utility staff and consultants, and have evolved since early drafts of Title IV of the Clean Air Act Amendments of 1990 (CAAA) began to circulate, several years back. The filings themselves often consist of many volumes of technical analysis, supporting documentation, and accompanying testimony. Hundreds of computer simulations are often presented and these, in turn, are underlain by hundreds of assumptions covering a staggering range of variables. Commissions usually have little time and few external resources with which to review and in some cases, preapprove proposed utility actions. There may be a tendency among commissions to forego a comprehensive review, approve utility plans as filed, and hope for the best. There are at least three important reasons, however, why this should not occur: (1) The magnitude of planned CAAA expenditures is large. (2) Preapproval, either formal or de facto, is becoming increasingly common. Although the approval of specific actions is certainly one outcome of the preapproval process, it should not be the sole or even principal outcome. The main focus of preapproval should involve defining an economic and institutional framework for how utilities, with input from regulators and the public, can best meet future customer needs. Done correctly, the preapproval process provides a meaningful, preexisting context which can be used to analyze outcomes. (3) Without adequate review market opportunities may be ignored and compliance costs increased unnecessarily. This article discusses the following topics in detail: CAAA Compliance Plan Review framework; Emission Reduction Alternatives: How Much is Enough?; Assumptions, Analytical Methods, and Evaluation Criteria of compliance plans; CAAA compliance costs and IRP. 2 figs., 3 tabs.

  4. After the Rain: Rain.

    ERIC Educational Resources Information Center

    Old Elk, Arlene; Stoklas, Jackie

    The Heard Museum (Phoenix, Arizona) has developed and updated an integrated curriculum for use in grades K-3. The goals for this curriculum are to: (1) share museum resources with schools; (2) promote cross-cultural understanding through a focus on rain, a universal requirement for life; (3) help students understand that Native Americans are…

  5. Cytoplasmic pH mediates pH taxis and weak-acid repellent taxis of bacteria.

    PubMed

    Kihara, M; Macnab, R M

    1981-03-01

    Bacteria migrate away from an acid pH and from a number of chemicals, including organic acids such as acetate; the basis for detection of these environmental cues has not been demonstrated. Membrane-permeant weak acids caused prolonged tumbling when added to Salmonella sp. or Escherichia coli cells at pH 5.5. Tethered Salmonella cells went from a prestimulus behavior of 14% clockwise rotation to 80% clockwise rotation when 40 mM acetate was added and remained this way for more than 30 min. A low external pH in the absence of weak acid did not markedly affect steady-state tumbling frequency. Among the weak acids tested, the rank for acidity (salicylate greater than benzoate greater than acetate greater than 5,5-dimethyl-2,4-oxazolidinedione) was the same as the rank for the ability to collapse the transmembrane pH gradient and to cause tumbling. At pH 7.0, the tumbling responses caused by the weak acids were much briefer. Indole, a non-weak-acid repellent, did not cause prolonged tumbling at low pH. Two chemotaxis mutants (a Salmonella mutant defective in the chemotaxis methylesterase and an E. coli mutant defective in the methyl-accepting protein in MCP I) showed inverse responses of enhanced counterclockwise rotation in the first 1 min after acetate addition. The latter mutant had been found previously to be defective in the sensing of gradients of extracellular pH and (at neutral pH) of acetate. We conclude (i) that taxes away from acid pH and membrane-permeant weak acids are both mediated by a pH-sensitive component located either in the cytoplasm or on the cytoplasmic side of the membrane, rather than by an external receptor (as in the case of the attractants), and (ii) that both of these taxes involve components of the chemotaxis methylation system, at least in the early phase of the response.

  6. High-resolution determination of H+ by ion chromatography. Application to the simultaneous determination of H+, Na+, NH4+ and K+ in acid rain.

    PubMed

    Hu, W; Hasebe, K; Iles, A; Tanaka, K

    2001-06-01

    An ion chromatographic (IC) method was developed for the high-resolution determination of a sample's free hydrogen ion concentration (H+). Highly purified lithium dodecyl sulfate was used as the stationary phase, a slightly acidified aqueous LiCl solution was used as the mobile phase and conductivity was used for analyte detection. An electrical double layer (EDL) containing H+ was established on the stationary phase by using a slightly acidified electrolyte solution as the eluent. H+ in the EDL protonated any weak acid groups (i.e., silanols) on the stationary phase so that H+ from the sample could be retained/separated purely by dodecyl sulfate. The optimum molar ratio of H+:Li+ in the EDL for this IC system was obtained by using an aqueous solution containing 40.0 mM LiCl and 0.07 mM H2SO4 as the eluent. After separation, H+ was detected by direct conductimetric measurement. An H+ detection limit of better than 8.2 x 10(-6) M was obtained from the analysis of standard aqueous H2SO4 solutions. Other monovalent cations could also be separated with this method, giving detection limits of 7.4 x 10(-5), 4.3 x 10(-5) and 4.2 x 10(-5) M for Na+, NH4+ and K+, respectively. The method was applied to the simultaneous determination of H+, Na+, NH4+ and K+ in acid rain. The results obtained showed a significant improvement in reproducibility when compared with those from a conventional pH-meter. Acid rain samples with a pH < 5 could be analyzed with this IC system.

  7. Effect of systemic pH on pH sub i and lactic acid generation in exhaustive forearm exercise

    SciTech Connect

    Hood, V.L.; Schubert, C.; Keller, U.; Mueller, S. Univ. of Vermont College of Medicine, Burlington )

    1988-09-01

    To investigate whether changes in systemic pH affect intracellular pH (pH{sub i}), energy-rich phosphates, and lactic acid generation in muscle, eight normal volunteers performed exhaustive forearm exercise with arterial blood flow occluded for 2 min on three occasions. Subjects ingested 4 mmol/kg NH{sub 4}Cl (acidosis; A) or NaHCO{sub 3} (alkalosis; B) or nothing (control; C) 3 h before the exercise. Muscle pH{sub i} and phosphocreatine (PCr) content were measured with {sup 31}P-nuclear magnetic resonance ({sup 31}P-NMR) spectroscopy during exercise and recovery. Lactate output during 0.5-7 min of recovery was calculated as deep venous-arterial concentration differences times forearm blood flow. Before exercise, blood pH and bicarbonate were lower in acidosis than alkalosis and intermediate in control. Lactic acid output during recovery was less with A than B and intermediate in C. PCr utilization and resynthesis were not affected by extracellular pH changes. pH{sub i} did not differ before exercise or at its end. Hence systemic acidosis inhibited and alkalosis stimulated lactic acid output. These findings suggest that systemic pH regulates cellular acid production, protecting muscle pH, at the expense of energy availability.

  8. Acid rain recovery may help to mitigate the impacts of climate change on thermally sensitive fish in lakes across eastern North America.

    PubMed

    Warren, Dana R; Kraft, Clifford E; Josephson, Daniel C; Driscoll, Charles T

    2016-12-15

    From the 1970s to 1990s, more stringent air quality regulations were implemented across North America and Europe to reduce chemical emissions that contribute to acid rain. Surface water pH slowly increased during the following decades, but biological recovery lagged behind chemical recovery. Fortunately, this situation is changing. In the past few years, northeastern US fish populations have begun to recover in lakes that were historically incapable of sustaining wild fish due to acidic conditions. As lake ecosystems across the eastern United States recover from acid deposition, the stress to the most susceptible populations of native coldwater fish appears to be shifting from acidification effects to thermal impacts associated with changing climate. Extreme summer temperature events - which are expected to occur with increasing frequency in the coming century - can stress and ultimately kill native coldwater fish in lakes where thermal stratification is absent or highly limited. Based on data from northeastern North America, we argue that recovery from acid deposition has the potential to improve the resilience of coldwater fish populations in some lakes to impacts of climate change. This will occur as the amount of dissolved organic carbon (DOC) in the water increases with increasing lake pH. Increased DOC will reduce water clarity and lead to shallower and more persistent lake thermoclines that can provide larger areas of coldwater thermal refuge habitat. Recovery from acidification will not eliminate the threat of climate change to coldwater fish, but secondary effects of acid recovery may improve the resistance of coldwater fish populations in lakes to the effects of elevated summer temperatures in historically acidified ecosystems. This analysis highlights the importance of considering the legacy of past ecosystem impacts and how recovery or persistence of those effects may interact with climate change impacts on biota in the coming decades.

  9. Effects of pH adjustment and sodium ions on sour taste intensity of organic acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Protonated organic acid species have been shown to be the primary stimuli responsible for sour taste of organic acids. However, we have observed that sour taste may be modulated when the pH of acid solutions is raised using sodium hydroxide. Objectives were to evaluate the effect of pH adjustment on...

  10. Interpretation of pH, acidity, and alkalinity in fisheries and aquaculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Measurements of pH, acidity, and alkalinity are commonly used to describe water quality. The three variables are interrelated and are sometimes confused. The pH of water is an intensity factor, while the acidity and alkalinity of waters are capacity factors. More precisely, acidity and alkalinity ar...

  11. Role of remote sensing in the study of acid rain impact on aquatic systems

    SciTech Connect

    Schott, J.R.; Wilkinson, M.A.

    1982-01-01

    Results are presented of a study of the capabilities of image analysis of remotely sensed data in the evaluation of the present state and past history of lakes subject to acidification by acid precipitation. Analysis of surface sampling data from nine Adirondack lakes reveals lake pH and alkalinity to be reflected in parameters related to optical properties, exhibiting a positive correlation with chlorophyll and total solids and a negative correlation with Secchi depth. Aerial photographic measurements of lake volume spectral reflectance, when compared with a simple laboratory model of the dependence of chlorophyll, lignin and humic acid contents of water on its optical properties, are also found to correlate with the differences between the in situ lake properties. Finally, analysis of Landsat band 4, 5, and 7 data obtained in September 1972 and 1979 for 18 lakes demonstrates the potential of the data for the isolation of lakes with low alkalinity, and for monitoring the rate of acidification over time providing data is properly calibrated for atmospheric, illumination and sensor response effects. Results thus demonstrate considerable potential for remote sensing in monitoring the impact of acidification on lakes, and point up the need for further studies of multi-temporal Landsat data and the techniques of aerial analysis.

  12. Spatial characterization of acid rain stress in Canadian Shield Lakes. Progress report, 1 August 1986-1 February 1987

    SciTech Connect

    Tanis, F.J.

    1987-01-01

    The acidification of lake waters from airborne pollution is of continental proportions both in North America and Europe. A major concern of the acid rain problem is the cumulative ecosystem damage to lakes and forest. The number of lakes affected in northeastern U.S. and on the Canadian Shield is though to be enormous. How seasonal changes in lake transparency are related to annual acidic load was examined. The relationship between variations in lake acidification and ecophysical units was also examined. The utility of Thematic Mapper based observations to measure seasonal changes in the optical transparency in acid lakes was investigated. The potential for this optical response is related to a number of local ecophysical factors with bedrock geology being, perhaps, the most important. Other factors include sulfate deposition, vegetative cover, and terrain drainage/relief. The area of southern Ontario contains a wide variety of geologies from the most acid rain sensitive granite quartzite types to the least sensitive limestone dolomite sediments. Annual sulfate deposition ranges from 1.0 to 4.0 grams/sq m.

  13. The PH gene determines fruit acidity and contributes to the evolution of sweet melons.

    PubMed

    Cohen, Shahar; Itkin, Maxim; Yeselson, Yelena; Tzuri, Galil; Portnoy, Vitaly; Harel-Baja, Rotem; Lev, Shery; Sa'ar, Uzi; Davidovitz-Rikanati, Rachel; Baranes, Nadine; Bar, Einat; Wolf, Dalia; Petreikov, Marina; Shen, Shmuel; Ben-Dor, Shifra; Rogachev, Ilana; Aharoni, Asaph; Ast, Tslil; Schuldiner, Maya; Belausov, Eduard; Eshed, Ravit; Ophir, Ron; Sherman, Amir; Frei, Benedikt; Neuhaus, H Ekkehard; Xu, Yimin; Fei, Zhangjun; Giovannoni, Jim; Lewinsohn, Efraim; Tadmor, Yaakov; Paris, Harry S; Katzir, Nurit; Burger, Yosef; Schaffer, Arthur A

    2014-06-05

    Taste has been the subject of human selection in the evolution of agricultural crops, and acidity is one of the three major components of fleshy fruit taste, together with sugars and volatile flavour compounds. We identify a family of plant-specific genes with a major effect on fruit acidity by map-based cloning of C. melo PH gene (CmPH) from melon, Cucumis melo taking advantage of the novel natural genetic variation for both high and low fruit acidity in this species. Functional silencing of orthologous PH genes in two distantly related plant families, cucumber and tomato, produced low-acid, bland tasting fruit, showing that PH genes control fruit acidity across plant families. A four amino-acid duplication in CmPH distinguishes between primitive acidic varieties and modern dessert melons. This fortuitous mutation served as a preadaptive antecedent to the development of sweet melon cultigens in Central Asia over 1,000 years ago.

  14. Fast-growing Acer rubrum differs from slow-growing Quercus alba in leaf, xylem and hydraulic trait coordination responses to simulated acid rain.

    PubMed

    Medeiros, Juliana S; Tomeo, Nicholas J; Hewins, Charlotte R; Rosenthal, David M

    2016-08-01

    We investigated the effects of historic soil chemistry changes associated with acid rain, i.e., reduced soil pH and a shift from nitrogen (N)- to phosphorus (P)-limitation, on the coordination of leaf water demand and xylem hydraulic supply traits in two co-occurring temperate tree species differing in growth rate. Using a full-factorial design (N × P × pH), we measured leaf nutrient content, water relations, leaf-level and canopy-level gas exchange, total biomass and allocation, as well as stem xylem anatomy and hydraulic function for greenhouse-grown saplings of fast-growing Acer rubrum (L.) and slow-growing Quercus alba (L.). We used principle component analysis to characterize trait coordination. We found that N-limitation, but not P-limitation, had a significant impact on plant water relations and hydraulic coordination of both species. Fast-growing A. rubrum made hydraulic adjustments in response to N-limitation, but trait coordination was variable within treatments and did not fully compensate for changing allocation across N-availability. For slow-growing Q. alba, N-limitation engendered more strict coordination of leaf and xylem traits, resulting in similar leaf water content and hydraulic function across all treatments. Finally, low pH reduced the propensity of both species to adjust leaf water relations and xylem anatomical traits in response to nutrient manipulations. Our data suggest that a shift from N- to P-limitation has had a negative impact on the water relations and hydraulic function of A. rubrum to a greater extent than for Q. alba We suggest that current expansion of A. rubrum populations could be tempered by acidic N-deposition, which may restrict it to more mesic microsites. The disruption of hydraulic acclimation and coordination at low pH is emphasized as an interesting area of future study.

  15. Acidic pH promotes intervertebral disc degeneration: Acid-sensing ion channel -3 as a potential therapeutic target

    PubMed Central

    Gilbert, Hamish T. J.; Hodson, Nathan; Baird, Pauline; Richardson, Stephen M.; Hoyland, Judith A.

    2016-01-01

    The aetiology of intervertebral disc (IVD) degeneration remains poorly understood. Painful IVD degeneration is associated with an acidic intradiscal pH but the response of NP cells to this aberrant microenvironmental factor remains to be fully characterised. The aim here was to address the hypothesis that acidic pH, similar to that found in degenerate IVDs, leads to the altered cell/functional phenotype observed during IVD degeneration, and to investigate the involvement of acid-sensing ion channel (ASIC) -3 in the response. Human NP cells were treated with a range of pH, from that of a non-degenerate (pH 7.4 and 7.1) through to mildly degenerate (pH 6.8) and severely degenerate IVD (pH 6.5 and 6.2). Increasing acidity of pH caused a decrease in cell proliferation and viability, a shift towards matrix catabolism and increased expression of proinflammatory cytokines and pain-related factors. Acidic pH resulted in an increase in ASIC-3 expression. Importantly, inhibition of ASIC-3 prevented the acidic pH induced proinflammatory and pain-related phenotype in NP cells. Acidic pH causes a catabolic and degenerate phenotype in NP cells which is inhibited by blocking ASIC-3 activity, suggesting that this may be a useful therapeutic target for treatment of IVD degeneration. PMID:27853274

  16. Dispelling the North American acid rain clouds: Developing a framework for political consensus through the identification of elite viewpoints

    SciTech Connect

    Bhatti, N.

    1988-01-01

    Acidic deposition has simultaneously been referred to as an environmental curiosity and as an ecological holocaust. This polarization of opinion on this pollutant has resulted in the policy stalemate in Congress over this issue and is responsible for the major part of the friction which currently besets Canada-United States relations. This study identified the distinctive viewpoints which characterize opposing attitudes. In addition, the specific areas of consensus and disagreement among these elite groups were determined. All of these objectives were carried out using the results of the Q-sort technique and interviews with members of the acid rain elite in both Canada and the United States (i.e. politicians, scientists, regulators, environmental/advocacy groups, and industry/utility personnel). Furthermore, a comprehensive, in-depth review of the scientific, legal, economic, social and political aspects of this tissue was conducted. Results show that implementation of the Acid Rain Experimental Control Program (ARECP) and the Clean Coal Technology project has the potential to break the existing stalemates over this issue and, at the same, could avert damage to many ecosystems, man-made structures and human health.

  17. A computer program for geochemical analysis of acid-rain and other low-ionic-strength, acidic waters

    USGS Publications Warehouse

    Johnsson, P.A.; Lord, D.G.

    1987-01-01

    ARCHEM, a computer program written in FORTRAN 77, is designed primarily for use in the routine geochemical interpretation of low-ionic-strength, acidic waters. On the basis of chemical analyses of the water, and either laboratory or field determinations of pH, temperature, and dissolved oxygen, the program calculates the equilibrium distribution of major inorganic aqueous species and of inorganic aluminum complexes. The concentration of the organic anion is estimated from the dissolved organic concentration. Ionic ferrous iron is calculated from the dissolved oxygen concentration. Ionic balances and comparisons of computed with measured specific conductances are performed as checks on the analytical accuracy of chemical analyses. ARCHEM may be tailored easily to fit different sampling protocols, and may be run on multiple sample analyses. (Author 's abstract)

  18. Organic Acid Excretion in Penicillium ochrochloron Increases with Ambient pH

    PubMed Central

    Vrabl, Pamela; Fuchs, Viktoria; Pichler, Barbara; Schinagl, Christoph W.; Burgstaller, Wolfgang

    2012-01-01

    Despite being of high biotechnological relevance, many aspects of organic acid excretion in filamentous fungi like the influence of ambient pH are still insufficiently understood. While the excretion of an individual organic acid may peak at a certain pH value, the few available studies investigating a broader range of organic acids indicate that total organic acid excretion rises with increasing external pH. We hypothesized that this phenomenon might be a general response of filamentous fungi to increased ambient pH. If this is the case, the observation should be widely independent of the organism, growth conditions, or experimental design and might therefore be a crucial key point in understanding the function and mechanisms of organic acid excretion in filamentous fungi. In this study we explored this hypothesis using ammonium-limited chemostat cultivations (pH 2–7), and ammonium or phosphate-limited bioreactor batch cultivations (pH 5 and 7). Two strains of Penicillium ochrochloron were investigated differing in the spectrum of excreted organic acids. Confirming our hypothesis, the main result demonstrated that organic acid excretion in P. ochrochloron was enhanced at high external pH levels compared to low pH levels independent of the tested strain, nutrient limitation, and cultivation method. We discuss these findings against the background of three hypotheses explaining organic acid excretion in filamentous fungi, i.e., overflow metabolism, charge balance, and aggressive acidification hypothesis. PMID:22493592

  19. EPA`s overview of the Acid Rain Program`s emissions tracking system (ETS) quarterly report process

    SciTech Connect

    Wockenfuss, M.E.

    1997-12-31

    The Acid Rain Program`s Emission Tracking System (ETS) was developed to collect, quality assure and publish the monitored and sampled emissions data collected and reported by the electric utility industry. Data are collected from fossil-fuel burning electrical generating stations that are affected by the Acid Rain Program. Since its operational start in 1993 the ETS and the data collection that surrounds it, the quarterly report process, has evolved to handle the Environmental Protection Agency`s (EPA) increased expectations of quarterly report data quality. The quarterly report process that supports the ETS provides utilities with multiple data submission options. It also provides software tools so that utilities can perform their own data assessment. This paper highlights the quarterly report process and the systems that are at the center of that process. It also analyzes utility performance relating to their 1995 and 1996 quarterly data reports and previews how the EPA`s quarterly report process will evolve over the next year.

  20. Combined impact of pH and organic acids on iron uptake by Caco-2 cells.

    PubMed

    Salovaara, Susan; Sandberg, Ann-Sofie; Andlid, Thomas

    2003-12-17

    Previous studies have shown that organic acids have an impact on both Fe(II) and Fe(III) uptake in Caco-2 cell. However, to what extent this effect is correlated with the anion of organic acids per se, or with the resulting decrease in pH, has not yet been clarified. Therefore, we studied the effect of five organic acids (tartaric, succinic, citric, oxalic, and propionic acid) on the absorption of Fe(II) and Fe(III) in Caco-2 cells and compared this with sample solutions without organic acids but set to equivalent pH by HCl. The results showed that the mechanisms behind the enhancing effect of organic acids differed for the two forms of iron. For ferric iron the organic acids promoted uptake both by chelation and by lowering the pH, whereas for ferrous iron the promoting effect was caused only by the lowered pH.

  1. Amino acids improve acid tolerance and internal pH maintenance in Bacillus cereus ATCC14579 strain.

    PubMed

    Senouci-Rezkallah, Khadidja; Schmitt, Philippe; Jobin, Michel P

    2011-05-01

    This study investigated the involvement of glutamate-, arginine- and lysine-dependent systems in the Acid Tolerance Response (ATR) of Bacillus cereus ATCC14579 strain. Cells were grown in a chemostat at external pH (pH(e)) 7.0 and 5.5. Population reduction after acid shock at pH 4.0 was strongly limited in cells grown at pH 5.5 (acid-adapted) compared with cells grown at pH 7.0 (unadapted), indicating that B. cereus cells grown at low pH(e) were able to induce a marked ATR. Glutamate, arginine and lysine enhanced the resistance of unadapted cells to pH 4.0 acid shock of 1-log or 2-log populations, respectively. Amino acids had no detectable effect on acid resistance in acid-adapted cells. An acid shock at pH 4.0 resulted in a marked drop in internal pH (pH(i)) in unadapted cells compared with acid-adapted cells. When acid shock was achieved in the presence of glutamate, arginine or lysine, pH(i) was maintained at higher values (6.31, 6.69 or 6.99, respectively) compared with pH(i) in the absence of amino acids (4.88). Acid-adapted cells maintained their pH(i) at around 6.4 whatever the condition. Agmatine (a competitive inhibitor of arginine decarboxylase) had a negative effect on the ability of B. cereus cells to survive and maintain their pH(i) during acid shock. Our data demonstrate that B. cereus is able to induce an ATR during growth at low pH. This adaptation depends on pH(i) homeostasis and is enhanced in the presence of glutamate, arginine and lysine. Hence evaluations of the pathogenicity of B. cereus must take into account its ability to adapt to acid stress.

  2. Effects of rhizobium, arbuscular mycorrhizal fungi and anion content of simulated rain on subterranean clover.

    PubMed

    Shafer, S R; Schoeneberger, M M; Horton, S J; Davey, C B; Miller, J E

    1996-01-01

    An experiment was conducted to determine the extent to which rhizobia, mycorrhizal fungi, and anions in simulated rain affect plant growth response to acid deposition. Germinating subterranean clover seeds were planted in steam-pasteurized soil in pots and inoculated with Rhizobium leguminosarum, Glomus intraradices, Glomus etunicatum, R. leguminosarum + G. intraradices, R. leguminosarum + G. etunicatum, or no microbial symbionts. Beginning 3 weeks later, plants and the soil surface were exposed to simulated rain in a greenhouse on 3 days week(-1) for 12 weeks. Rain solutions were deionized water amended with background ions only (pH 5.0) or also adjusted to pH 3.0 with HNO3 only, H2SO4 only, or a 50/50 mixture of the two acids. Glomus intraradices colonized plant roots poorly, and G. intraradices-inoculated plants responded like nonmycorrhizal plants to rhizobia and rain treatments. Variation in plant biomass attributable to different rain formulations was strongest for G. etunicatum-inoculated plants, and the effect of rain formulation differed with respect to nodulation by rhizobia. The smallest plants at the end of the experiment were noninoculated plants exposed to rains (0.38 g mean dry weight total for 3 plants pot(-1)). Among nonnodulated plants infected by G. etunicatum, those exposed to HNO3 rain were largest, followed by plants exposed to HNO3 + H2SO4, pH 5.0, and H2SO4 rain, in that order. Among plants inoculated with both R. leguminosarum + G. etunicatum, however, the greatest biomass occurred with pH 5.0 rains, resulting in the largest plants in the study (1.00 g/3 plants). Treatment-related variation among root and shoot biomass data reflected those for whole-plant biomass. Based on quantification of biomass and N concentrations in shoot and root tissues, total N content of plants inoculated with G. etunicatum alone and exposed to the HNO3 + H2SO4 rains was approximately the same as plants inoculated with R. leguminosarum + G. entunicatum and exposed

  3. A combined proteomic and transcriptomic analysis on sulfur metabolism pathways of Arabidopsis thaliana under simulated acid rain.

    PubMed

    Liu, Tingwu; Chen, Juan A; Wang, Wenhua; Simon, Martin; Wu, Feihua; Hu, Wenjun; Chen, Juan B; Zheng, Hailei

    2014-01-01

    With rapid economic development, most regions in southern China have suffered acid rain (AR) pollution. In our study, we analyzed the changes in sulfur metabolism in Arabidopsis under simulated AR stress which provide one of the first case studies, in which the systematic responses in sulfur metabolism were characterized by high-throughput methods at different levels including proteomic, genomic and physiological approaches. Generally, we found that all of the processes related to sulfur metabolism responded to AR stress, including sulfur uptake, activation and also synthesis of sulfur-containing amino acid and other secondary metabolites. Finally, we provided a catalogue of the detected sulfur metabolic changes and reconstructed the coordinating network of their mutual influences. This study can help us to understand the mechanisms of plants to adapt to AR stress.

  4. A Combined Proteomic and Transcriptomic Analysis on Sulfur Metabolism Pathways of Arabidopsis thaliana under Simulated Acid Rain

    PubMed Central

    Wang, Wenhua; Simon, Martin; Wu, Feihua; Hu, Wenjun; Chen, Juan B.; Zheng, Hailei

    2014-01-01

    With rapid economic development, most regions in southern China have suffered acid rain (AR) pollution. In our study, we analyzed the changes in sulfur metabolism in Arabidopsis under simulated AR stress which provide one of the first case studies, in which the systematic responses in sulfur metabolism were characterized by high-throughput methods at different levels including proteomic, genomic and physiological approaches. Generally, we found that all of the processes related to sulfur metabolism responded to AR stress, including sulfur uptake, activation and also synthesis of sulfur-containing amino acid and other secondary metabolites. Finally, we provided a catalogue of the detected sulfur metabolic changes and reconstructed the coordinating network of their mutual influences. This study can help us to understand the mechanisms of plants to adapt to AR stress. PMID:24595051

  5. Weak-acid preservatives: pH and proton movements in the yeast Saccharomyces cerevisiae.

    PubMed

    Stratford, Malcolm; Nebe-von-Caron, Gerhard; Steels, Hazel; Novodvorska, Michaela; Ueckert, Joerg; Archer, David B

    2013-02-15

    Weak-acid preservatives commonly used to prevent fungal spoilage of low pH foods include sorbic and acetic acids. The "classical weak-acid theory" proposes that weak acids inhibit spoilage organisms by diffusion of undissociated acids through the membrane, dissociation within the cell to protons and anions, and consequent acidification of the cytoplasm. Results from 25 strains of Saccharomyces cerevisiae confirmed inhibition by acetic acid at a molar concentration 42 times higher than sorbic acid, in contradiction of the weak-acid theory where all acids of equal pK(a) should inhibit at equimolar concentrations. Flow cytometry showed that the intracellular pH fell to pH 4.7 at the growth-inhibitory concentration of acetic acid, whereas at the inhibitory concentration of sorbic acid, the pH only fell to pH 6.3. The plasma membrane H⁺-ATPase proton pump (Pma1p) was strongly inhibited by sorbic acid at the growth-inhibitory concentration, but was stimulated by acetic acid. The H⁺-ATPase was also inhibited by lower sorbic acid concentrations, but later showed recovery and elevated activity if the sorbic acid was removed. Levels of PMA1 transcripts increased briefly following sorbic acid addition, but soon returned to normal levels. It was concluded that acetic acid inhibition of S. cerevisiae was due to intracellular acidification, in accord with the "classical weak-acid theory". Sorbic acid, however, appeared to be a membrane-active antimicrobial compound, with the plasma membrane H⁺-ATPase proton pump being a primary target of inhibition. Understanding the mechanism of action of sorbic acid will hopefully lead to improved methods of food preservation.

  6. Effects of simulated acid rain on the cyanobacterial diazotroph Tolypothrix sp

    SciTech Connect

    Olsen, E.W.

    1983-01-01

    This study consisted of four experiments. 1) Tolypothrix was incubated in aqueous HSO/sub 3//sup -/ solutions at concentrations 0-10 ppm adjusted to pH 7.2 to 3.0 with H/sub 2/SO/sub 4/. The effects on nitrogen (C/sub 2/H/sub 2/) fixation, net photosynthesis and respiration were measured. 2) Tolypothrix was grown for seven days in liquid culture adjusted to pH 6.5-4.0 with either HNO/sub 3/ or H/sub 2/SO/sub 4/. The effects on nitrogen (C/sub 2/H/sub 2/) fixation, net photosynthesis, respiration, growth rate, chlorophyll a, and phycocyanin were determined. 3) Soils were inoculated with Tolypothrix and sprayed with dilute medium adjusted to pH 6.0-2.0 with either HNO/sub 3/ or H/sub 2/SO/sub 4/. The effects on nitrogen (C/sub 2/H/sub 2/) fixation and chlorophyll a were measured. 4) Agropyron smithii seeds were planted in Tolypothrix-inoculated and noninoculated soils. Germination rates, biomass and nitrogen content of the grass were measured. Nitrogen (C/sub 2/H/sub 2/) fixation was the most sensitive parameter to changes in pH and HSO/sub 3//sup -/ concentration. Net photosynthesis and respiration were less sensitive. However, there was no measureable O/sub 2/ evolution or consumption at pH 4.0 and pH 3.0. Nitrogen (C/sub 2/H/sub 2/) fixation rates declined over the 7-day incubation period at all pHs, going to zero at pH 5.0 and 4.5, as did net photosynthesis. Whereas, respiration rates remained fairly constant at pH 6.0 and increased over time at pH 5.5 and below. Tolypothrix exhibited the typical logarithmic growth curve only at pH 6.0 and pH 5.5 at pH 5.0 and pH 5.5 the optical density of the cultures remained constant during the seven-day period.

  7. [Relationship between atmospheric particles and rain water chemistry character].

    PubMed

    Huo, Ming-Qun; Sun, Qian; Xie, Peng; Bai, Yu-Hua; Liu, Zhao-Rong; Li, Ji-Long; Lu, Si-Hua

    2009-11-01

    Rain and atmospheric particle samples were collected in the rural area of Taian and Shenzhen in 2007, respectively. Rain sampling was carried out during the precipitation process and several samples were got from the beginning of one precipitation to the end. The chemical character changes during precipitation and the changes of concentration of particles before and after rain were studied in this research to understand the contribution of particles on the rain chemical character and the rain-out effect for particles. The volume-weighted mean pH of rainwater in Taian was 5.97 and the total concentration of ions was 1 187.96 microeq x L(-1). The mass concentration of PM10 in Taian was 131.76 microg/m3 and that of PM2.5 was 103.84 microg/m3. The volume-weighted mean pH of rainwater in Shenzhen was 4.72 and the total concentration of ions was 175.89 microeq x L(-1). The mass concentration of PM10 in Shenzhen was 56.66 microg/m3 and that of PM2.5 was 41.52 microg/m3. During precipitation process pH and ion concentration of rain decrease and it is shown the neutralizing effect happens. The difference between rainwater of Taian and Shenzhen is due to cloud water acidity, atmospheric particles character and atmospheric acid-basic gases concentration. The clean-up effect of Na+ and Ca2+ by rain is high and which of NH4+ and NO3- is low. The clean-up effect for mass concentration, ions concentration and element concentration of particles by rain are significant.

  8. Negative pH and extremely acidic mine waters from Iron Mountain, California

    USGS Publications Warehouse

    Nordstrom, D.K.; Alpers, C.N.; Ptacek, C.J.; Blowes, D.W.

    2000-01-01

    Extremely acidic mine waters with pH values as low as -3.6, total dissolved metal concentrations as high as 200 g/L, and sulfate concentrations as high as 760 g/L, have been encountered underground in the Richmond Mine at Iron Mountain, CA. These are the most acidic waters known. The pH measurements were obtained by using the Pitzer method to define pH for calibration of glass membrane electrodes. The calibration of pH below 0.5 with glass membrane electrodes becomes strongly nonlinear but is reproducible to a pH as low as -4. Numerous efflorescent minerals were found forming from these acid waters. These extreme acid waters were formed primarily by pyrite oxidation and concentration by evaporation with minor effects from aqueous ferrous iron oxidation and efflorescent mineral formation.

  9. Acid rain program emissions scorecard 1997. SO[sub 2], NO[sub x], heat input, and CO[sub 2] emission trends in the electric utility industry

    SciTech Connect

    Not Available

    1999-01-01

    Established under Title IV of the Clean Air Act Amendments of 1990, the Acid Rain Program requires the electric utility industry to reduce emissions of sulfur dioxide (SO[sub 2]) and nitrogen oxides (NO[sub x]), the pollutants that cause acid rain. To ensure that the desired emission reductions are achieved, the program implements an innovative market-based regulatory approach with utilities having flexible compliance options. After each calendar year, EPA determines the compliance of each facility relating to its SO[sub 2] and NO[sub x] emissions requirements and publishes a report documenting the results.

  10. A structural transition in class II major histocompatibility complex proteins at mildly acidic pH

    PubMed Central

    1996-01-01

    Peptide binding by class II major histocompatibility complex proteins is generally enhanced at low pH in the range of hydrogen ion concentrations found in the endosomal compartments of antigen- presenting cells. We and others have proposed that class II molecules undergo a reversible conformational change at low pH that is associated with enhanced peptide loading. However, no one has previously provided direct evidence for a structural change in class II proteins in the mildly acidic pH conditions in which enhanced peptide binding is observed. In this study, susceptibility to denaturation induced by sodium dodecyl sulfate (SDS) detergent or heat was used to probe the conformation of class II at different hydrogen ion concentrations. Class II molecules became sensitive to denaturation at pH 5.5-6.5 depending on the allele and experimental conditions. The observed structural transition was fully reversible if acidic pH was neutralized before exposure to SDS or heat. Experiments with the environment- sensitive fluorescent probe ANS (8-anilino-1-naphthalene-sulfonic acid) provided further evidence for a reversible structural transition at mildly acidic pH associated with an increase in exposed hydrophobicity in class II molecules. IAd conformation was found to change at a higher pH than IEd, IEk, or IAk, which correlates with the different pH optimal for peptide binding by these molecules. We conclude that pH regulates peptide binding by influencing the structure of class II molecules. PMID:8551215

  11. Continuous intra-arterial blood pH monitoring in rabbits with acid-base disorders.

    PubMed

    Jin, Weizhong; Jiang, Jinjun; Wang, Xun; Zhu, Xiaodan; Wang, Guifang; Song, Yuanlin; Bai, Chunxue

    2011-07-31

    The acid-base balance of arterial blood is important for the clinical management of seriously ill patients, especially patients with acute lung injury or acute respiratory distress syndrome. We developed a novel fluorosensor for continuous blood pH monitoring and evaluated its performance both in vitro and in vivo in rabbits with acid-base disorders. The pH sensor is made of N-allyl-4-piperazinyl-1, 8-napthalimide and 2-hydroxyethyl methacrylate, which were bonded at the distal end of the optical fiber. The fluorescence intensity increased as the pH decreased with good reproducibility, selectivity and linearity in the pH range of 6-8. The pH measurement precision was 0.03 ± 0.03 pH units with a bias of -0.02 ± 0.04 (n = 105) and -0.00 ± 0.05 pH units (n=189) in rabbits with metabolic and respiratory acid-base orders, respectively. The optical pH sensor can accurately measure pH fluctuations with a fast response and is a promising candidate for continuous in-line measurements of blood pH in critical care patients.

  12. Photosynthetic and antioxidant responses of Liquidambar formosana and Schima superba seedlings to sulfuric-rich and nitric-rich simulated acid rain.

    PubMed

    Chen, Juan; Wang, Wen-Hua; Liu, Ting-Wu; Wu, Fei-Hua; Zheng, Hai-Lei

    2013-03-01

    To study whether differential responses occur in photosynthesis and antioxidant system for seedlings of Liquidambar formosana, an acid rain (AR)-sensitive tree species and Schima superba, an AR-tolerant tree species treated with three types of pH 3.0 simulated AR (SiAR) including sulfuric-rich (S-SiAR), nitric-rich (N-SiAR), sulfate and nitrate mixed (SN-SiAR), we investigated the changes of leaf necrosis, chlorophyll content, soluble protein and proline content, photosynthesis and chlorophyll fluorescence characteristics, reactive oxygen species production, membrane lipid peroxidation, small molecular antioxidant content, antioxidant enzyme activities and related protein expressions. Our results showed that SiAR significantly caused leaf necrosis, inhibited photosynthesis, induced superoxide radical and hydrogen peroxide generation, aggravated membrane lipid peroxidation, changed antioxidant enzyme activities, modified related protein expressions such as Cu/Zn superoxide dismutase (SOD), l-ascorbate peroxidase (APX, EC 1. 11. 1. 11), glutathione S transferase (GST, EC 2. 5. 1. 18) and Rubisco large subunit (RuBISCO LSU), altered non-protein thiols (NPT) and glutathione (GSH) content in leaves of L. formosana and S. superba. Taken together, we concluded that the damages caused by SiAR in L. formosana were more severe and suffered from more negative impacts than in S. superba. S-SiAR induced more serious damages for the plants than did SN-SiAR and N-SiAR.

  13. A novel acidic pH fluorescent probe based on a benzothiazole derivative.

    PubMed

    Ma, Qiujuan; Li, Xian; Feng, Suxiang; Liang, Beibei; Zhou, Tiqiang; Xu, Min; Ma, Zhuoyi

    2017-04-15

    A novel acidic pH fluorescent probe 1 based on a benzothiazole derivative has been designed, synthesized and developed. The linear response range covers the acidic pH range from 3.44 to 6.46, which is valuable for pH researches in acidic environment. The evaluated pKa value of the probe 1 is 4.23. The fluorescence enhancement of the studied probe 1 with an increase in hydrogen ions concentration is based on the hindering of enhanced photo-induced electron transfer (PET) process. Moreover, the pH sensor possesses a highly selective response to H(+) in the presence of metal ions, anions and other bioactive small molecules which would be interfere with its fluorescent pH response. Furthermore, the probe 1 responds to acidic pH with short response time that was less than 1min. The probe 1 has been successfully applied to confocal fluorescence imaging in live HeLa cells and can selectively stain lysosomes. All of such good properties prove it can be used to monitoring pH fluctuations in acidic environment with high sensitivity, pH dependence and short response time.

  14. A novel acidic pH fluorescent probe based on a benzothiazole derivative

    NASA Astrophysics Data System (ADS)

    Ma, Qiujuan; Li, Xian; Feng, Suxiang; Liang, Beibei; Zhou, Tiqiang; Xu, Min; Ma, Zhuoyi

    2017-04-01

    A novel acidic pH fluorescent probe 1 based on a benzothiazole derivative has been designed, synthesized and developed. The linear response range covers the acidic pH range from 3.44 to 6.46, which is valuable for pH researches in acidic environment. The evaluated pKa value of the probe 1 is 4.23. The fluorescence enhancement of the studied probe 1 with an increase in hydrogen ions concentration is based on the hindering of enhanced photo-induced electron transfer (PET) process. Moreover, the pH sensor possesses a highly selective response to H+ in the presence of metal ions, anions and other bioactive small molecules which would be interfere with its fluorescent pH response. Furthermore, the probe 1 responds to acidic pH with short response time that was less than 1 min. The probe 1 has been successfully applied to confocal fluorescence imaging in live HeLa cells and can selectively stain lysosomes. All of such good properties prove it can be used to monitoring pH fluctuations in acidic environment with high sensitivity, pH dependence and short response time.

  15. Cut-off net acid generation pH in predicting acid-forming potential in mine spoils.

    PubMed

    Liao, B; Huang, L N; Ye, Z H; Lan, C Y; Shu, W S

    2007-01-01

    Acidification of mine wastes can lead to a series of environmental problems, such as acid drainage, heavy metal mobilization, and ecosystem degradation. Prediction of acid-forming potential is one of the key steps in management of sulfide-bearing mine wastes. In this paper, the acid-forming potential of 180 mine waste samples collected from 17 mine sites in China were studied using a net acid generation (NAG) method. The samples contained different contents of total sulfur (ranging from 0.6 to 200 g kg(-1)), pyritic sulfur (ranging from 0 to 100 g kg(-1)), and acid neutralization capacity (ANC, ranging from -41 to 274 kg H2SO4 t(-1)). Samples with high acid-forming potential are generally due to their high sulfur content or low acid neutralization capacity. After the samples were oxidized by H2O2, the amounts of acid generation and the final NAG pH were measured. Results indicated that the final NAG pH gave a well-defined demarcation between acid-forming and non-acid-forming materials. Samples with final NAG pH >or= 5 could be classified as non-acid-forming materials, while those with NAG pH acid-forming materials. Materials with NAG pH > 2.5, but < 5, had low risk of being acid-forming. The confirmation of cut-off NAG pH will be used as a rapid and cost-effective operational monitoring tool for the in-pit prediction of acid-forming potential of mine wastes and classification of waste types.

  16. Acidic pH of the lateral intercellular spaces of MDCK cells cultured on permeable supports.

    PubMed

    Chatton, J Y; Spring, K R

    1994-06-01

    The pH of the lateral intercellular space (LIS) of Madin-Darby canine kidney (MDCK) cell monolayers grown on permeable supports was investigated by microspectrofluorimetry using BCECF (2',7'-bis(carboxyethyl)-5,6-carboxyfluorescein). The permeability of the support was selectively reduced by growing Zn-Al-silicate crystals inside its pores. The diffusion of BCECF across the filter was sufficiently retarded to allow measurements of fluorescence in the LIS. The LIS pH and intracellular pH of the cells surrounding them were determined in HEPES-buffered solutions. When the perfusate pH was 7.4, the LIS pH was more acidic (7.06 +/- 0.02) and equaled the cytoplasmic pH (7.08 +/- 0.05). When perfusate was changed to pH 7.0 or 7.8, the LIS changed linearly by about half the magnitude of the perfusate pH. Intracellular pH followed LIS pH variations between perfusate pH 7.0 and 7.4 but was significantly higher when perfusate pH was 7.8. Tight junctional H+ permeability was undetectably low. The low steady-state pH in the LIS was not altered by inhibitors of acid transport or low temperature. Rapid perturbations of pH in the LIS showed that protons were not immobilized in the LIS. The acidic microenvironment within the LIS may be the result of buffering by the cell surface proteins.

  17. Effect of initial solution pH on photo-induced reductive decomposition of perfluorooctanoic acid.

    PubMed

    Qu, Yan; Zhang, Chao-Jie; Chen, Pei; Zhou, Qi; Zhang, Wei-Xian

    2014-07-01

    The effects of initial solution pH on the decomposition of perfluorooctanoic acid (PFOA) with hydrated electrons as reductant were investigated. The reductive decomposition of PFOA depends strongly on the solution pH. In the pH range of 5.0-10.0, the decomposition and defluorination rates of PFOA increased with the increase of the initial solution pH. The rate constant was 0.0295 min(-1) at pH 10.0, which was more than 49.0 times higher than that at pH 5.0. Higher pH also inhibits the generation of toxic intermediates during the PFOA decomposition. For example, the short-chain PFCAs reached a lower maximum concentration in shorter reaction time as pH increasing. The peak areas of accumulated fluorinated and iodinated hydrocarbons detected by GC/MS under acidic conditions were nearly 10-100 times more than those under alkaline conditions. In short, alkaline conditions were more favorable for photo-induced reduction of PFOA as high pH promoted the decomposition of PFOA and inhibited the accumulation of intermediate products. The concentration of hydrated electron, detected by laser flash photolysis, increased with the increase of the initial pH. This was the main reason why the decomposition of PFOA in the UV-KI system depended strongly on the initial pH.

  18. Primordial soup or vinaigrette: did the RNA world evolve at acidic pH?

    PubMed Central

    2012-01-01

    Background The RNA world concept has wide, though certainly not unanimous, support within the origin-of-life scientific community. One view is that life may have emerged as early as the Hadean Eon 4.3-3.8 billion years ago with an atmosphere of high CO2 producing an acidic ocean of the order of pH 3.5-6. Compatible with this scenario is the intriguing proposal that life arose within alkaline (pH 9-11) deep-sea hydrothermal vents like those of the 'Lost City', with the interface with the acidic ocean creating a proton gradient sufficient to drive the first metabolism. However, RNA is most stable at pH 4-5 and is unstable at alkaline pH, raising the possibility that RNA may have first arisen in the acidic ocean itself (possibly near an acidic hydrothermal vent), acidic volcanic lake or comet pond. As the Hadean Eon progressed, the ocean pH is inferred to have gradually risen to near neutral as atmospheric CO2 levels decreased. Presentation of the hypothesis We propose that RNA is well suited for a world evolving at acidic pH. This is supported by the enhanced stability at acidic pH of not only the RNA phosphodiester bond but also of the aminoacyl-(t)RNA and peptide bonds. Examples of in vitro-selected ribozymes with activities at acid pH have recently been documented. The subsequent transition to a DNA genome could have been partly driven by the gradual rise in ocean pH, since DNA has greater stability than RNA at alkaline pH, but not at acidic pH. Testing the hypothesis We have proposed mechanisms for two key RNA world activities that are compatible with an acidic milieu: (i) non-enzymatic RNA replication of a hemi-protonated cytosine-rich oligonucleotide, and (ii) specific aminoacylation of tRNA/hairpins through triple helix interactions between the helical aminoacyl stem and a single-stranded aminoacylating ribozyme. Implications of the hypothesis Our hypothesis casts doubt on the hypothesis that RNA evolved in the vicinity of alkaline hydrothermal vents. The

  19. A neutral ceramidase homologue from Dictyostelium discoideum exhibits an acidic pH optimum.

    PubMed Central

    Monjusho, Hatsumi; Okino, Nozomu; Tani, Motohiro; Maeda, Mineko; Yoshida, Motonobu; Ito, Makoto

    2003-01-01

    The nucleotide sequence reported for the Dictyostelium discoideum ceramidase is available on the DNA Data Bank of Japan (DDBJ). Ceramidases (CDases) are currently classified into three categories (acid, neutral and alkaline) based on their optimal pHs and primary structures. Here, we report the first exception to this rule. We cloned the CDase cDNA, consisting of 2142 nucleotides encoding 714 amino-acid residues, from the slime mould, Dictyostelium discoideum. The putative amino-acid sequence indicates 32-42% identity with various neutral CDases, but does not show any similarity to the acid and alkaline CDases, indicating the enzyme should be classified as a neutral CDase. However, overexpression of the cDNA in D. discoideum resulted in increased CDase activity at an acidic, but not a neutral pH range. Knockout of the gene in slime mould eliminated CDase activity at acidic pH. The recombinant enzyme expressed in the slime mould was purified and then characterized. Consequently, the purified CDase was found to exhibit the maximal activity at approx. pH 3.0. The singular pH dependency of slime mould CDase is not derived from the specific post-translational modification in the slime mould, because the enzyme showed an acidic pH optimum even when expressed in Chinese hamster ovary cells, whereas rat neutral-CDase exhibited a neutral pH optimum when expressed in slime mould. PMID:12943537

  20. Spatial and spectral characterization of acid rain stress in Canadian Shield lakes

    NASA Technical Reports Server (NTRS)

    Marshall, Elizabeth J.; Tanis, Frederick J.

    1989-01-01

    Results from this study demonstrate that a remote sensor can discriminate lake clarity based upon reflection. The basic hypothesis was that seasonal and multiyear changes in lake optical transparency are indicative of sensitivity to acidic deposition. In many acid-sensitive lakes optical transparency is controlled by the amount of dissolved organic carbon (DOC) present. DOC is a strong absorbing, nonscattering material which has the greatest impact at short visible wavelengths, including Thematic Mapper band 1. Acid-sensitive lakes have high concentrations of aluminum which have been mobilized by acidic components contained in the runoff. Aluminum complexing with DOC is considered to be the primary mechanism to account for observed increases in lake transparency in acid-sensitive lakes. Thus seasonal changes in the optical transparency of lakes should provide an indication of the stress due to acid deposition and loading.

  1. Red spruce decline in the northeastern US: hypotheses regarding the role of acid rain

    SciTech Connect

    Johnson, A.H.

    1983-11-01

    Red spruce have died in abnormal numbers in the high elevation forests of New York and New England during the past two decades while spruce in the southern Appalachians remain healthy. Investigations of insect damage, fungai pathogens, successional dynamics, competitive status, climate and weather patterns, and possible pollutant effects indicate that the decline was triggered by abiotic stress during the dry years of the 1960s. Tree response, as recorded in the pattern of annual rings, and the wide range of soil conditions in which spruce are declining, suggest drought or dry summers as key factors. Hypotheses regarding the role of acid deposition induced stress have been offered, but at present there is not evidence which clearly links acid deposition to spruce decline. Indirect effects of acid deposition on soils, direct effects of acid deposition on foliage, and interactions of acid deposition and drought stress are possible but unproven pathways by which acid deposition could be involved. 23 references, 6 figures, 1 table.

  2. Formation of elastic whey protein gels at low pH by acid equilibration.

    PubMed

    Vardhanabhuti, Bongkosh; Khayankan, Worarat; Foegeding, E Allen

    2010-06-01

    Whey protein gels have a weak/brittle texture when formed at pH pH is required to produce a high-protein, shelf-stable product. We investigated if gels could be made under conditions that produced strong/elastic textural properties then adjusted to pH pH 7.5). Equilibration in acid solutions caused gel swelling and lowered pH because of the diffusion of water and H(+) into the gels. The type and concentration of acid, and presence of other ions, in the equilibrating solutions influenced pH, swelling ratio, and fracture properties of the gels. Swelling of gels decreased fracture stress (because of decreased protein network density) but caused little change to fracture strain, thus maintaining a desirable strong/elastic fracture pattern. We have shown that whey protein isolate gels can be made at pH acid type, acid concentration, pH of equilibrating solution, and equilibrating time.

  3. A Three-Tier Diagnostic Test to Assess Pre-Service Teachers' Misconceptions about Global Warming, Greenhouse Effect, Ozone Layer Depletion, and Acid Rain

    ERIC Educational Resources Information Center

    Arslan, Harika Ozge; Cigdemoglu, Ceyhan; Moseley, Christine

    2012-01-01

    This study describes the development and validation of a three-tier multiple-choice diagnostic test, the atmosphere-related environmental problems diagnostic test (AREPDiT), to reveal common misconceptions of global warming (GW), greenhouse effect (GE), ozone layer depletion (OLD), and acid rain (AR). The development of a two-tier diagnostic test…

  4. PERSISTENT EPISODIC ACIDIFICATION OF STREAMS LINKED TO ACID RAIN EFFECTS ON SOIL

    EPA Science Inventory

    Episodic acidification of streams, identified in the late 1980s as one of the most significant environmental problems caused by acidic deposition, had not been evaluated since the early 1990s despite decreasing levels of acidic deposition over the past decade. This analysis indic...

  5. Persistent episodic acidification of streams linked to acid rain effects on soil

    USGS Publications Warehouse

    Lawrence, G.B.

    2002-01-01

    Episodic acidification of streams, identified in the late 1980s as one of the most significant environmental problems caused by acidic deposition, had not been evaluated since the early 1990s despite decreasing levels of acidic deposition over the past decade. This analysis indicates that episodic acidification of streams in upland regions in the northeastern United States persists, and is likely to be much more widespread than chronic acidification. Depletion of exchangeable Ca in the mineral soil has decreased the neutralization capacity of soils and increased the role of the surface organic horizon in the neutralization of acidic soil water during episodes. Increased accumulation of N and S in the forest floor from decades of acidic deposition will delay the recovery of soil base status, and therefore, the elimination of acidic episodes, which is anticipated from decreasing emissions.

  6. Volatile fatty acids distribution during acidogenesis of algal residues with pH control.

    PubMed

    Li, Yan; Hua, Dongliang; Zhang, Jie; Zhao, Yuxiao; Xu, Haipeng; Liang, Xiaohui; Zhang, Xiaodong

    2013-06-01

    The anaerobic acidification of protein-rich algal residues with pH control (4, 6, 8, 10) was studied in batch reactors, which was operated at mesophilic(35 °C) condition. The distribution of major volatile fatty acids (VFAs) during acidogenesis was emphasized in this paper. The results showed that the acidification efficiency and VFAs distribution in the acid reactor strongly depended on the pH. The main product for all the runs involved acetic acid except that the proportion of butyric acid acidified at pH 6 was relatively higher. The other organic acids remained at lower levels. The VFAs yield reached the maximum value with about 0.6 g VFAs/g volatile solid (VS) added as pH was 8, and also the content of total ammonia nitrogen (TAN) reached the highest values of 9,629 mg/l. Low acidification degrees were obtained under the conditions at pH 4 and 10, which was not suitable for the metabolism of acidogens. Hydralic retention time (HRT) required for different conditions varied. As a consequence, it was indicated that pH was crucial to the acidification efficiency and products distribution. The investigation of acidogenesis process, which was producing the major substrates, short-chain fatty acids, would play the primary role in the efficient operation of methanogenesis.

  7. Degradation of vanillin in soil-clay mixtures treated with simulated acid rain

    SciTech Connect

    Bewley, R.J.F.; Stotzky, G.

    1984-06-01

    Significant vanillin degradation occurred only in soil amended with 9% montmorillonite and not in soil amended with 9% kaolinite or in soil without addition of clay minerals. Progressively decreasing amounts of vanillin were mineralized in the montmorillonite-amended soil with increasing acidification with H/sub 2/SO/sub 4/, and complete inhibition of mineralization occurred at a soil pH of 1.6. 16 references, 1 table.

  8. Change of pH during excess sludge fermentation under alkaline, acidic and neutral conditions.

    PubMed

    Yuan, Yue; Peng, Yongzhen; Liu, Ye; Jin, Baodan; Wang, Bo; Wang, Shuying

    2014-12-01

    The change in pH during excess sludge (ES) fermentation of varying sludge concentrations was investigated in a series of reactors at alkaline, acidic, and neutral pHs. The results showed that the changes were significantly affected by fermentative conditions. Under different conditions, pH exhibited changing profiles. When ES was fermented under alkaline conditions, pH decreased in a range of (10±1). At the beginning of alkaline fermentation, pH dropped significantly, at intervals of 4h, 4h, and 5h with sludge concentrations of 8665.6mg/L, 6498.8mg/L, and 4332.5mg/L, then it would become moderate. However, under acidic conditions, pH increased from 4 to 5. Finally, under neutral conditions pH exhibited a decrease then an increase throughout entire fermentation process. Further study showed short-chain fatty acids (SCFAs), ammonia nitrogen and cations contributed to pH change under various fermentation conditions. This study presents a novel strategy based on pH change to predict whether SCFAs reach their stable stage.

  9. Effect of pH on fecal recovery of energy derived from volatile fatty acids.

    PubMed

    Kien, C L; Liechty, E A

    1987-01-01

    We assessed the effect of pH on volatilization of short-chain fatty acids during lyophilization. Acetic, propionic, valeric, and butyric acids were added to a fecal homogenate in amounts sufficient to raise the energy density by 18-27%. Fecal homogenate samples were either acidified (pH 2.8-3.2), alkalinized (pH 7.9-8.7), or left unchanged (4.0-4.8) prior to lyophilization and subsequent bomb calorimetry. Alkalinizing the fecal samples prevented the 20% loss of energy derived from each of these volatile fatty acids observed in samples either acidified or without pH adjustment. These data suggest that in energy balance studies involving subjects with active colonic fermentation, fecal samples should be alkalinized prior to lyophilization and bomb calorimetry.

  10. Chronic and episodic acidification of Adirondack streams from acid rain in 2003-2005

    USGS Publications Warehouse

    Lawrence, G.B.; Roy, K.M.; Baldigo, Barry P.; Simonin, H.A.; Capone, S.B.; Sutherland, J.W.; Nierzwicki-Bauer, S. A.; Boylen, C.W.

    2008-01-01

    Limited information is available on streams in the Adirondack region of New York, although streams are more prone to acidification than the more studied Adirondack lakes. A stream assessment was therefore undertaken in the Oswegatchie and Black River drainages; an area of 4585 km2 in the western part of the Adirondack region. Acidification was evaluated with the newly developed base-cation surplus (BCS) and the conventional acid-neutralizing capacity by Gran titration (ANCG). During the survey when stream water was most acidic (March 2004), 105 of 188 streams (56%) were acidified based on the criterion of BCS < 0 ??eq L-1, whereas 29% were acidified based on an ANCG value < 0 ??eq L-1. During the survey when stream water was least acidic (August 2003), 15 of 129 streams (12%) were acidified based on the criterion of BCS < 0 ??eq L-1, whereas 5% were acidified based on ANCG value < 0 ??eq L -1. The contribution of acidic deposition to stream acidification was greater than that of strongly acidic organic acids in each of the surveys by factors ranging from approximately 2 to 5, but was greatest during spring snowmelt and least during elevated base flow in August. During snowmelt, the percentage attributable to acidic deposition was 81%, whereas during the October 2003 survey, when dissolved organic carbon (DOC) concentrations were highest, this percentage was 66%. The total length of stream reaches estimated to be prone to acidification was 718 km out of a total of 1237 km of stream reaches that were assessed. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

  11. Perfluorinated acids in air, rain, snow, surface runoff, and lakes: relative importance of pathways to contamination of urban lakes.

    PubMed

    Kim, Seung-Kyu; Kannan, Kurunthachalam

    2007-12-15

    Concentrations of perfluorinated acids (PFAs) were measured in various environmental matrices (air, rain, snow, surface runoff water, and lake water) in an urban area, to enable identification of sources and pathways of PFAs to urban water bodies. Total PFA concentrations ranged from 8.28 to 16.0 pg/ m3 (mean 11.3) in bulk air (sum of vapor and particulate phases), 0.91 to 13.2 ng/L (6.19) in rainwater, 0.91 to 23.9 ng/L (7.98) in snow, 1.11-81.8 ng/L (15.1 ng/L) in surface runoff water (SRW), and 9.49 to 35.9 ng/L (21.8) in lake water. Perfluorooctanoic acid (PFOA) was the predominant compound, accounting for > 35% of the total PFA concentrations, in all environmental matrices analyzed. Concentrations and relative compositions of PFAs in SRW were similar to those found for urban lakes. SRW contributes to contamination by PFOA in urban lakes. The measured concentration ratios of FTOH to PFOA in air were 1-2 orders of magnitude lower than the ratios calculated based on an assumption of exclusive atmospheric oxidation of FTOHs. Nevertheless, the mass balance analysis suggested the presence of an unknown input pathway that could contribute to a significant amount of total PFOA loadings to the lake. Flux estimates of PFOA at the air-water interface in the urban lake suggest net volatilization from water.

  12. Effects of calcium on seed germination, seedling growth and photosynthesis of six forest tree species under simulated acid rain.

    PubMed

    Liu, Ting-Wu; Wu, Fei-Hua; Wang, Wen-Hua; Chen, Juan; Li, Zhen-Ji; Dong, Xue-Jun; Patton, Janet; Pei, Zhen-Ming; Zheng, Hai-Lei

    2011-04-01

    We selected six tree species, Pinus massoniana Lamb., Cryptomeria fortunei Hooibr. ex Otto et Dietr., Cunninghamia lanceolata (Lamb.) Hook., Liquidambar formosana Hance, Pinus armandii Franch. and Castanopsis chinensis Hance, which are widely distributed as dominant species in the forest of southern China where acid deposition is becoming more and more serious in recent years. We investigated the effects and potential interactions between simulated acid rain (SiAR) and three calcium (Ca) levels on seed germination, radicle length, seedling growth, chlorophyll content, photosynthesis and Ca content in leaves of these six species. We found that the six species showed different responses to SiAR and different Ca levels. Pinus armandii and C. chinensis were very tolerant to SiAR, whereas the others were more sensitive. The results of significant SiAR × Ca interactions on different physiological parameters of the six species demonstrate that additional Ca had a dramatic rescue effect on the seed germination and seedling growth for the sensitive species under SiAR. Altogether, we conclude that the negative effects of SiAR on seed germination, seedling growth and photosynthesis of the four sensitive species could be ameliorated by Ca addition. In contrast, the physiological processes of the two tolerant species were much less affected by both SiAR and Ca treatments. This conclusion implies that the degree of forest decline caused by long-term acid deposition may be attributed not only to the sensitivity of tree species to acid deposition, but also to the Ca level in the soil.

  13. Potential human health effects of acid rain: report of a workshop

    PubMed Central

    Goyer, Robert A.; Bachmann, John; Clarkson, Thomas W.; Ferris, Benjamin G.; Graham, Judith; Mushak, Paul; Perl, Daniel P.; Rall, David P.; Schlesinger, Richard; Sharpe, William; Wood, John M.

    1985-01-01

    This report summarizes the potential impact of the acid precipitation phenomenon on human health. There are two major components to this phenomenon: the predepositional phase, during which there is direct human exposure to acidic substances from ambient air, and the post-depositional phase, in which the deposition of acid materials on water and soil results in the mobilization, transport, and even chemical transformation of toxic metals. Acidification increases bioconversion of mercury to methylmercury, which accumulates in fish, increasing the risk to toxicity in people who eat fish. Increase in water and soil content of lead and cadmium increases human exposure to these metals which become additive to other sources presently under regulatory control. The potential adverse health effects of increased human exposure to aluminum is not known at the present time. PMID:3896772

  14. Fungal populations in podzolic soil experimentally acidified to simulate acid rain

    SciTech Connect

    Baath, E.; Lundgren, B.; Soederstroem, B.

    1984-01-01

    The effect of experimental acidification on the soil microfungal community was studied in the humus layer of a coniferous forest in northern Sweden. The study was made 4 years after the last application of sulfuric acid. Fungal species composition was altered by treatments of 100 and 150 kg sulfuric acid ha/sup -1/ each year for 6 years, yet no differences were found between the control treatment and an application of 50 kg ha/sup -1/. The abundance of Penicillium spinulosum and Oidiodendron cf. echinulatum II increased with increasing rates of acid application, whereas only small changes were found for other isolated fungal taxa. Soil respiration rate and fluorescein diacetate (FDA)-active fungal biomass were significantly different from the control treatment at all 3 levels of acidification. 15 references, 4 tables.

  15. Interaction forces and membrane charge tunability: Oleic acid containing membranes in different pH conditions.

    PubMed

    Kurniawan, James; Suga, Keishi; Kuhl, Tonya L

    2017-02-01

    Oleic acid is known to interact with saturated lipid molecules and increase the fluidity of gel phase lipid membranes. In this work, the thermodynamic properties of mixed monolayers of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and oleic acid at the air-water interface were determined using Langmuir isotherms. The isotherm study revealed an attractive interaction between oleic acid and DPPC. The incorporation of oleic acid also monotonically decreased the elastic modulus of the monolayer indicative of higher fluidity with increasing oleic acid content. Using the surface force apparatus, intermembrane force-distance profiles were obtained for substrate supported DPPC membranes containing 30mol% oleic acid at pH5.8 and 7.4. Three different preparation conditions resulted in distinct force profiles. Membranes prepared in pH5.8 subphase had a low number of nanoscopic defects ≤1% and an adhesion magnitude of ~0.6mN/m. A slightly higher defect density of 1-4% was found for membranes prepared in a physiological pH7.4 subphase. The presence of the exposed hydrophobic moieties resulted in a higher adhesion magnitude of 2.9mN/m. Importantly, at pH7.4, some oleic acid deprotonates resulting in a long-range electrostatic repulsion. Even though oleic acid increased the DPPC bilayer fluidity and the number of defects, no membrane restructuring was observed indicating that the system maintained a stable configuration.

  16. Insulin Fibrillization at Acidic and Physiological pH Values is Controlled by Different Molecular Mechanisms.

    PubMed

    Noormägi, Andra; Valmsen, Karin; Tõugu, Vello; Palumaa, Peep

    2015-12-01

    Formation of amyloid-like fibrils by insulin was studied at different insulin concentrations, pH and temperatures. At low pH (pH 2.5) the insulin fibrillization occurred only at high ([10 lM) peptide concentrations, whereas at physiological pH values the fibril formation is inhibited at higher insulin concentrations. The enthalpy of activation Ea of the fibril growth at pH 2.5 equals to 33 kJ/mol, which is considerably lower than 84 kJ/mol at physiological pH. The fibrillization rate of insulin decreases with increasing pH at high, 250 lM concentration, which was opposite to the pH effect observed in 2.5 lM insulin solutions. The latter effect indicates that protonation of histidine residues seems to be important for the fibrillization of monomeric insulin, whereas the pH effect at high concentration may result from off-pathway oligomerization propensity. Together, the different effect of environmental factors on the insulin fibrillization suggest that the reaction rate is controlled by different molecular events in acidic conditions and at physiological pH values.

  17. Acid Precipitation Awareness Curriculum Materials in the Life Sciences.

    ERIC Educational Resources Information Center

    Stubbs, Harriett S.

    1983-01-01

    Provides an outline of course content for acid precipitation and two acid rain activities (introduction to pH and effects of acid rain on an organism). Information for obtaining 20 additional activities as well as an information packet containing booklets, pamphlets, and articles are also provided. (JN)

  18. The pH ruler: a Java applet for developing interactive exercises on acids and bases.

    PubMed

    Barrette-Ng, Isabelle H

    2011-07-01

    In introductory biochemistry courses, it is often a struggle to teach the basic concepts of acid-base chemistry in a manner that is relevant to biological systems. To help students gain a more intuitive and visual understanding of abstract acid-base concepts, a simple graphical construct called the pH ruler Java applet was developed. The applet allows students to visualize the abundance of different protonation states of diprotic and triprotic amino acids at different pH values. Using the applet, the student can drag a widget on a slider bar to change the pH and observe in real time changes in the abundance of different ionization states of this amino acid. This tool provides a means for developing more complex inquiry-based, active-learning exercises to teach more advanced topics of biochemistry, such as protein purification, protein structure and enzyme mechanism.

  19. Air Pollution, Acid Rain, and the Future of Forests. Worldwatch Paper 58.

    ERIC Educational Resources Information Center

    Postel, Sandra

    This book traces centuries of human use and abuse of forest ecosystems by discussing past decades of intense burning, grazing, and timber cutting that added to the natural acidification of the soil. Air pollutants and acids generated by industrial activities worldwide are also considered. Many forests in Europe and North America now receive as…

  20. Sensitivity of acid-adapted and acid-shocked Shigella flexneri to reduced pH achieved with acetic, lactic, and propionic acids.

    PubMed

    Tetteh, G L; Beuchat, L R

    2001-07-01

    Survival and growth characteristics of unadapted, acid-adapted, and acid-shocked Shigella flexneri 2a cells in acidified (pH 3.5 to 5.5) tryptic soy broth with 0.25% glucose (TSB) and tryptic soy agar (TSA) were determined. S. flexneri was grown at 37 degrees C for 18 h in tryptic soy broth without glucose (TSBNG) (unadapted) and TSBNG supplemented with 1% glucose (TSBG) (acid-adapted). Cells grown in TSBNG were acid shocked by adjusting 16-h cultures to pH 5.05 +/- 0.05 with lactic acid. Cells were then inoculated into TSB acidified with acetic, lactic, or propionic acids to pH 5.5, 4.5, or 3.5 and incubated at 37 degrees C for 6 h. The order of lethality at a given pH was lactic acid < acetic acid < propionic acid. Significantly (P < or = 0.05) higher numbers of acid-adapted cells, compared to acid-shocked and unadapted cells, were recovered from TSB acidified (pH 3.5) with lactic or acetic acids. None of the cells survived a 30-min exposure in TSB acidified with propionic acid to pH 3.5. When the three cell types were plated on TSA acidified with lactic, acetic, or propionic acids at pH < or = 4.5, < or = 5.5, and < or = 5.5, respectively, visible colonies were not detected. Viable unadapted, acid-adapted, and acid-shocked cells were, however, recovered from TSA acidified with all three acids at pH > or = 4.5. Acid-adapted and, to a lesser extent, acid-shocked cells survived at lower pH than did unadapted cells, indicating that prior exposure to mild acidic environment results in increased acid resistance. Survival of S. flexneri at a given pH was influenced by the type of acidulant used, a response characteristic exhibited by other gram-negative enteric pathogens.

  1. Effect of pH on conjugated linoleic acid (CLA) formation of linolenic acid biohydrogenation by ruminal microorganisms.

    PubMed

    Lee, Yongjae

    2013-08-01

    Conventional beliefs surrounding the linolenic acid (LNA; cis-9 cis-12 cis-15 C18:3) biohydrogenation (BH) pathway propose that it converts to stearic acid (SA) without the formation of conjugated linoleic acid (CLA) as intermediate isomers. However, an advanced study (Lee and Jenkins, 2011) verified that LNA BH yields multiple CLAs. This study utilized the stable isotope tracer to investigate the BH intermediates of (13)C-LNA with different pH conditions (5.5 and 6.5). The (13)C enrichment was calculated as a (13)C/(12)C ratio of labeled minus unlabeled. After 24 h, eight CLA isomers were significantly enriched on both pH treatment, this result verifies that these CLAs originated from (13)C-LNA BH which supports the results of Lee and Jenkins (2011). The enrichment of cis-cis double bond CLAs (cis-9 cis-11 and cis-10 cis-12 CLA) were significantly higher at low pH conditions. Furthermore, the concentration of cis-10 cis-12 CLA at low pH was four times higher than at high pH conditions after a 3 h incubation. These differences support the LNA BH pathways partial switch under different pH conditions, with a strong influence on the cis-cis CLA at low pH. Several mono-, di-, and tri-enoic fatty acid isomers were enriched during 24 h of incubation, but the enrichment was decreased or restricted at low pH treatment. Based on these results, it is proposed that low pH conditions may cause a changed or limited capacity of the isomerization and reduction steps in BH.

  2. Qualitative and quantitative status of the field grown potato crop stressed by acidified rain. Final progress report

    SciTech Connect

    Pell, E.J.

    1986-06-01

    In 1983 and 1984 experiments were conducted to determine the impact of simulated acidic rain on Solanum tuberosum L. cv. Norchip plants grown under standard field practices. Plots, 2.1 m/sup 2/ in area, received 0.5 cm of simulated rain three times per week at pH 2.8, 3.8, 4.6 or 5.6, throughout the growing season. Two 9 x 26m greenhouses mounted on rails covered the plots when simulated rain was being delivered and during ambient rain events. At the end of the growing season, tubers were harvested and it was determined that simulated acid rain did not affect weight, number, total solid, total glycoalkaloid or sugar content of potato tubers. In a second series of experiments the ability of simulated acidic rain to induce ethylene emission was investigated for foliage of Solanum tuberosum L. cv. 'Norland', Raphanus sativus cv. 'Cherry Belle', and Glycine max cv. 'Amsoy'. Greenhouse grown plants were treated with simulated acidic rain solutions of pH 2.8, 3.8, 4.6 or 5.6 for 1-hr/day for a single day or 1-hr/day for three consecutive days. No species exhibited increased ethylene production in response to 1-hr rain treatments. After multiple rain treatments, plants treated with pH 2.8 rain generally exhibited increased ethylene production. However, no direct relationship between ethylene production and treatment acidity was observed. 41 refs., 1 figs., 13 tabs.

  3. Acidic Food pH Increases Palatability and Consumption and Extends Drosophila Lifespan12

    PubMed Central

    Deshpande, Sonali A; Yamada, Ryuichi; Mak, Christine M; Hunter, Brooke; Obando, Alina Soto; Hoxha, Sany; Ja, William W

    2015-01-01

    Background: Despite the prevalent use of Drosophila as a model in studies of nutrition, the effects of fundamental food properties, such as pH, on animal health and behavior are not well known. Objectives: We examined the effect of food pH on adult Drosophila lifespan, feeding behavior, and microbiota composition and tested the hypothesis that pH-mediated changes in palatability and total consumption are required for modulating longevity. Methods: We measured the effect of buffered food (pH 5, 7, or 9) on male gustatory responses (proboscis extension), total food intake, and male and female lifespan. The effect of food pH on germfree male lifespan was also assessed. Changes in fly-associated microbial composition as a result of food pH were determined by 16S ribosomal RNA gene sequencing. Male gustatory responses, total consumption, and male and female longevity were additionally measured in the taste-defective Pox neuro (Poxn) mutant and its transgenic rescue control. Results: An acidic diet increased Drosophila gustatory responses (40–230%) and food intake (5–50%) and extended survival (10–160% longer median lifespan) compared with flies on either neutral or alkaline pH food. Alkaline food pH shifted the composition of fly-associated bacteria and resulted in greater lifespan extension (260% longer median survival) after microbes were eliminated compared with flies on an acidic (50%) or neutral (130%) diet. However, germfree flies lived longer on an acidic diet (5–20% longer median lifespan) compared with those on either neutral or alkaline pH food. Gustatory responses, total consumption, and longevity were unaffected by food pH in Poxn mutant flies. Conclusions: Food pH can directly influence palatability and feeding behavior and affect parameters such as microbial growth to ultimately affect Drosophila lifespan. Fundamental food properties altered by dietary or drug interventions may therefore contribute to changes in animal physiology, metabolism, and

  4. Properties of acid whey as a function of pH and temperature.

    PubMed

    Chandrapala, Jayani; Duke, Mikel C; Gray, Stephen R; Zisu, Bogdan; Weeks, Mike; Palmer, Martin; Vasiljevic, Todor

    2015-07-01

    Compositional differences of acid whey (AW) in comparison with other whey types limit its processability and application of conventional membrane processing. Hence, the present study aimed to identify chemical and physical properties of AW solutions as a function of pH (3 to 10.5) at 4 different temperatures (15, 25, 40, or 90°C) to propose appropriate membrane-processing conditions for efficient use of AW streams. The concentration of minerals, mainly calcium and phosphate, and proteins in centrifuged supernatants was significantly lowered with increase in either pH or temperature. Lactic acid content decreased with pH decline and rose at higher temperatures. Calcium appeared to form complexes with phosphates and lactates mainly, which in turn may have induced molecular attractions with the proteins. An increase in pH led to more soluble protein aggregates with large particle sizes. Surface hydrophobicity of these particles increased significantly with temperature up to 40°C and decreased with further heating to 90°C. Surface charge was clearly pH dependent. High lactic acid concentrations appeared to hinder protein aggregation by hydrophobic interactions and may also indirectly influence protein denaturation. Processing conditions such as pH and temperature need to be optimized to manipulate composition, state, and surface characteristics of components of AW systems to achieve an efficient separation and concentration of lactic acid and lactose.

  5. Sources of ions producing acidic rain and visibility impairment at Grand Canyon, Arizona

    SciTech Connect

    Sisler, J.F.; Malm, W.C.; Gebbart, K.A. )

    1988-01-01

    Effective management of visibility or wet acidic deposition in selected receptor areas requires an understanding of which chemical/aerosol species are responsible for the effect, the sources of these chemical/aerosol species and the relationships between how changes in emissions of chemical precursors result in changes in chemical/aerosol species at receptor sites. This paper addresses the first two issues at Grand Canyon, Arizona. At Grand Canyon National Park, Arizona, the National Acid Deposition Program/National Trends Network (NADP/NTN) monitoring site has been collocated with the Nation Park Service (NPS) aerosol monitoring site. The monitors were operated simultaneously for nearly three years, allowing a direct comparison between the causes and sources of wet deposition and the causes and sources of fine particulate matter.

  6. Role of acid pH and deficient efflux of pyrazinoic acid in unique susceptibility of Mycobacterium tuberculosis to pyrazinamide.

    PubMed

    Zhang, Y; Scorpio, A; Nikaido, H; Sun, Z

    1999-04-01

    Pyrazinamide (PZA) is an important antituberculosis drug. Unlike most antibacterial agents, PZA, despite its remarkable in vivo activity, has no activity against Mycobacterium tuberculosis in vitro except at an acidic pH. M. tuberculosis is uniquely susceptible to PZA, but other mycobacteria as well as nonmycobacteria are intrinsically resistant. The role of acidic pH in PZA action and the basis for the unique PZA susceptibility of M. tuberculosis are unknown. We found that in M. tuberculosis, acidic pH enhanced the intracellular accumulation of pyrazinoic acid (POA), the active derivative of PZA, after conversion of PZA by pyrazinamidase. In contrast, at neutral or alkaline pH, POA was mainly found outside M. tuberculosis cells. PZA-resistant M. tuberculosis complex organisms did not convert PZA into POA. Unlike M. tuberculosis, intrinsically PZA-resistant M. smegmatis converted PZA into POA, but it did not accumulate POA even at an acidic pH, due to a very active POA efflux mechanism. We propose that a deficient POA efflux mechanism underlies the unique susceptibility of M. tuberculosis to PZA and that the natural PZA resistance of M. smegmatis is due to a highly active efflux pump. These findings may have implications with regard to the design of new antimycobacterial drugs.

  7. Combining Long-Term Watershed Monitoring at Buck Creek with Spatially Extensive Ecosystem Data to Understand the Processes of Acid Rain Effects and Recovery

    NASA Astrophysics Data System (ADS)

    Lawrence, G. B.; Ross, D. S.; Sullivan, T. J.; McDonnell, T. C.; Bailey, S. W.; Dukett, J. E.

    2014-12-01

    The Buck Creek Monitoring Watershed, in the western Adirondack Region of New York, has provided long-term data back to 1982 for tracking acid rain effects and recovery, and for supporting fundamental research on environmental change. At Buck Creek, monitoring acidic deposition effects as they worsened, then diminished, has advanced our understanding of key biogeochemical processes such as Al mobilization. Although Al mobilization has been one of the primary adverse effects of acidic deposition, in the recovery phase it is now affecting terrestrial and aquatic ecosystems in new ways that could be both positive and negative, as soils and surface waters respond to further declines in acidic deposition. Using stream Al measurements from Buck Creek over varying seasons and flows, a new index, the base cation surplus (BCS), was developed to account for dissolved organic carbon (DOC) effects on the relationship between ANC and inorganic Al. Mobilization of inorganic Al, the form toxic to biota, occurs below a BCS of zero, regardless of DOC concentrations. Soil and stream data from Adirondack surveys showed that a BCS value of zero corresponds to a soil base saturation value in the B horizon of approximately 12%. Additional Adirondack survey work indicated that, where sugar maple stands grew in soils with base saturation values below 12%, seedling regeneration was nearly zero, suggesting a link between Al mobilization and impairment of tree regeneration. In recovering Adirondack lakes, the BCS was also used to show that increasing trends in DOC were accelerating decreases of inorganic Al beyond what would be expected from the increasing trends of ANC. Similar decreases of inorganic Al in Buck Creek, were coupled with increases in organic Al concentrations, which resulted in no trend in total Al concentrations despite a strong increase in pH. Sampling of Buck Creek soils in 1997, and again in 2009-2010, indicated a substantial decrease in forest floor exchangeable Al, of

  8. Natively unfolded human prothymosin alpha adopts partially folded collapsed conformation at acidic pH.

    PubMed

    Uversky, V N; Gillespie, J R; Millett, I S; Khodyakova, A V; Vasiliev, A M; Chernovskaya, T V; Vasilenko, R N; Kozlovskaya, G D; Dolgikh, D A; Fink, A L; Doniach, S; Abramov, V M

    1999-11-09

    Prothymosin alpha has previously been shown to be unfolded at neutral pH, thus belonging to a growing family of "natively unfolded" proteins. The structural properties and conformational stability of recombinant human prothymosin alpha were characterized at neutral and acidic pH by gel filtration, SAXS, circular dichroism, ANS fluorescence, (1)H NMR, and resistance to urea-induced unfolding. Interestingly, prothymosin alpha underwent a cooperative transition from the unfolded state into a partially folded conformation on lowering the pH. This conformation of prothymosin alpha is a compact denatured state, with structural properties different from those of the molten globule. The formation of alpha-helical structure by the glutamic acid-rich elements of the protein accompanied by the partial hydrophobic collapse is expected at lower pH due to the neutralization of the negatively charged residues. It is possible that such conformational changes may be associated with the protein function.

  9. Effects of pH adjustment and sodium ions on sour taste intensity of organic acids.

    PubMed

    Neta, E R D; Johanningsmeier, S D; Drake, M A; McFeeters, R F

    2009-01-01

    Protonated organic acid species have been shown to be the primary stimuli responsible for sour taste of organic acids. However, we have observed that sour taste may be modulated when the pH of acid solutions is raised using sodium hydroxide. Objectives were to evaluate the effect of pH adjustment on sour taste of equimolar protonated organic acid solutions and to investigate the potential roles of organic anions and sodium ions on sour taste perception. Despite equal concentrations of protonated acid species, sour taste intensity decreased significantly with increased pH for acetic, lactic, malic, and citric acids (P < 0.05). Total organic anion concentration did not explain the suppression of sour taste in solutions containing a blend of 3 organic acids with constant concentration of protonated organic acid species and hydrogen ions and variable organic anion concentrations (R(2)= 0.480, P = 0.12). Sour taste suppression in these solutions seemed to be more closely related to sodium ions added in the form of NaOH (R(2)= 0.861, P = 0.007). Addition of 20 mM NaCl to acid solutions resulted in significant suppression of sour taste (P = 0.016). However, sour taste did not decrease with further addition of NaCl up to 80 mM. Presence of sodium ions was clearly shown to decrease sour taste of organic acid solutions. Nonetheless, suppression of sour taste in pH adjusted single acid solutions was greater than what would be expected based on the sodium ion concentration alone, indicating an additional suppression mechanism may be involved.

  10. Preliminary results of the correlation between ion concentrations in rainwater samples and atmospheric back trajectories as a part of the study {open_quotes}impact to acid rain in the deterioration of Mexican Maya monuments{close_quotes} (project Conacyt-UNAM: 0128T9106)

    SciTech Connect

    Bravo, A.H.; Saavedra, M.I.; Snchez, P.; Camacho, R.

    1996-12-31

    The environmental Pollution Section at the Center of Atmospheric Sciences, National Autonomus University of Mexico (UNAM), has been conducting a research project on their potential of impact of acid rain on the Mexican Maya monuments since 1993. As a part of such study, 49 rainwater samples were collected during the years 1994 through 1995 at the Puerto Morelos Oceanographic Station Located close to the Tulum Maya ruins in the State of Qintana Roo. The rain water samples were collected using an automatic rain collector. After the rain event, the water samples were transferred to clean Nalgene bottles. The bottles were stored under refrigeration prior to their shipment to the UNAM laboratory in Mexico City. Concentrations of anions Cl{sup -}, NO{sup -}{sub 3}, and SO{sup 2-}{sub 4} and cations Na{sup +}, NH{sup +}{sub 4}, K{sup +}, Mg{sup 2+} an Ca{sup 2+} were determined by the High Pressure Ion Chromatographic Procedure. The pH of samples was measured in the laboratory. Also, wind back upper trajectories which arrived to the Puerto Morelos are at the same date of each rain event, were calculated using the GMCC atmospheric trajectory program at NOAA. A thorough analysis on the relations between anions and cations is made and preliminary correlations of these results with the calculated long range trajectories are explored in order to find the possible origin of the event.

  11. Acid rain and tree physiology: an overview of some possible mechanisms of response

    SciTech Connect

    McLaughlin, S.B.

    1983-01-01

    Several concepts which should be considered in addressing likely mechanisms by which acid deposition and air pollution in general can affect plant productivity are briefly discussed. These include: (1) multiple components of natural terrestrial systems may be affected; (2) plant response must be examined from a whole-plant perspective; (3) sensitivities of shoots and roots may differ markedly; (4) changing environmental availability and potential phytotoxicity of several trace elements should be examined; and (5) air pollution constitutes only one of many stresses which may contribute to forest declines. 6 references, 3 figures, 2 tables. (ACR)

  12. Seawater strontium isotopes, acid rain, and the Cretaceous-Tertiary boundary

    NASA Technical Reports Server (NTRS)

    Macdougall, J. D.

    1988-01-01

    A large bolide impact at the end of the Cretaceous would have produced significant amounts of nitrogen oxides by shock heating of the atmosphere. The resulting acid precipitation would have increased continental weathering greatly and could be an explanation for the observed high ratio of strontium-87 to strontium-86 in seawater at about this time, due to the dissolution of large amounts of strontium from the continental crust. Spikes to high values in the seawater strontium isotope record at other times may reflect similar episodes.

  13. Comparative Proteomic Analysis Reveals the Effects of Exogenous Calcium against Acid Rain Stress in Liquidambar formosana Hance Leaves.

    PubMed

    Hu, Wen-Jun; Wu, Qian; Liu, Xiang; Shen, Zhi-Jun; Chen, Juan; Liu, Ting-Wu; Chen, Juan; Zhu, Chun-Quan; Wu, Fei-Hua; Chen, Lin; Wei, Jia; Qiu, Xiao-Yun; Shen, Guo-Xin; Zheng, Hai-Lei

    2016-01-04

    Acid rain (AR) impacts forest health by leaching calcium (Ca) away from soils and plants. Ca is an essential element and participates in various plant physiological responses. In the present study, the protective role of exogenous Ca in alleviating AR stress in Liquidambar formosana Hance at the physiological and proteomic levels was examined. Our results showed that low Ca condition resulted in the chlorophyll content and photosynthesis decreasing significantly in L. formosana leaves; however, these effects could be reversed by high Ca supplementation. Further proteomic analyses successfully identified 81 differentially expressed proteins in AR-treated L. formosana under different Ca levels. In particular, some of the proteins are involved in primary metabolism, photosynthesis, energy production, antioxidant defense, transcription, and translation. Moreover, quantitative real time polymerase chain reaction (qRT-PCR) results indicated that low Ca significantly increased the expression level of the investigated Ca-related genes, which can be reversed by high Ca supplementation under AR stress. Further, Western blotting analysis revealed that exogenous Ca supply reduced AR damage by elevating the expression of proteins involved in the Calvin cycle, reactive oxygen species (ROS) scavenging system. These findings allowed us to better understand how woody plants respond to AR stress at various Ca levels and the protective role of exogenous Ca against AR stress in forest tree species.

  14. Populus yunnanensis males adopt more efficient protective strategies than females to cope with excess zinc and acid rain.

    PubMed

    Jiang, Hao; Korpelainen, Helena; Li, Chunyang

    2013-05-01

    Dioecious plants show sexually different responses to environmental stresses. However, little is known about the dimorphic morphological and physiological responses to soil pollution. To investigate sex-related adaptive responses of Populus yunnanensis seedlings when exposed to excess zinc (Zn), acid rain (AR) and their combination (Zn+AR), we analyzed growth parameters, Zn accumulation and allocation, photosynthetic capacity and biochemical responses under different treatments. Results revealed that both excess Zn and Zn+AR have a negative effect on plant growth. Males have a greater potential than females to enrich Zn. The photosynthesis limitation could be attributable to a lower stomatal conductance, photosynthetic nitrogen use efficiency and nitrate reductase activity induced by Zn accumulation. Overproduction of reactive oxygen species was detected, and females showed higher levels of H2O2 and O2- than did males under excess Zn and Zn+AR. In addition, indicators related to plant injury showed expected increases and exhibited sexual differences. Males synthesized more biochemical molecules, such as proline and non-protein thiol, showing a stronger defense capacity in responses to either excess Zn or Zn+AR. Taking into account the Zn accumulation and the resulting injuries in plants, we suggest that excess Zn causes sex-related adaptive responses and males possess a more effective self-protection mechanism, Zn-stressed individuals suffering from AR did not show notable aggravation or alleviation when compared to damages induced by excess Zn alone.

  15. Comparative proteomic analysis of differential responses of Pinus massoniana and Taxus wallichiana var. mairei to simulated acid rain.

    PubMed

    Hu, Wen-Jun; Chen, Juan; Liu, Ting-Wu; Simon, Martin; Wang, Wen-Hua; Chen, Juan; Wu, Fei-Hua; Liu, Xiang; Shen, Zhi-Jun; Zheng, Hai-Lei

    2014-03-12

    Acid rain (AR), a serious environmental issue, severely affects plant growth and development. As the gymnosperms of conifer woody plants, Pinus massoniana (AR-sensitive) and Taxus wallichiana var. mairei (AR-resistant) are widely distributed in southern China. Under AR stress, significant necrosis and collapsed lesions were found in P. massoniana needles with remarkable yellowing and wilting tips, whereas T. wallichiana var. mairei did not exhibit chlorosis and visible damage. Due to the activation of a large number of stress-related genes and the synthesis of various functional proteins to counteract AR stress, it is important to study the differences in AR-tolerance mechanisms by comparative proteomic analysis of tolerant and sensitive species. This study revealed a total of 65 and 26 differentially expressed proteins that were identified in P. massoniana and T. wallichiana var. mairei, respectively. Among them, proteins involved in metabolism, photosynthesis, signal transduction and transcription were drastically down-regulated in P. massoniana, whereas most of the proteins participating in metabolism, cell structure, photosynthesis and transcription were increased in T. wallichiana var. mairei. These results suggest the distinct patterns of protein expression in the two woody species in response to AR, allowing a deeper understanding of diversity on AR tolerance in forest tree species.

  16. Initial pH of medium affects organic acids production but do not affect phosphate solubilization

    PubMed Central

    Marra, Leandro M.; de Oliveira-Longatti, Silvia M.; Soares, Cláudio R.F.S.; de Lima, José M.; Olivares, Fabio L.; Moreira, Fatima M.S.

    2015-01-01

    The pH of the culture medium directly influences the growth of microorganisms and the chemical processes that they perform. The aim of this study was to assess the influence of the initial pH of the culture medium on the production of 11 low-molecular-weight organic acids and on the solubilization of calcium phosphate by bacteria in growth medium (NBRIP). The following strains isolated from cowpea nodules were studied: UFLA03-08 (Rhizobium tropici), UFLA03-09 (Acinetobacter sp.), UFLA03-10 (Paenibacillus kribbensis), UFLA03-106 (Paenibacillus kribbensis) and UFLA03-116 (Paenibacillus sp.). The strains UFLA03-08, UFLA03-09, UFLA03-10 and UFLA03-106 solubilized Ca3(PO4)2 in liquid medium regardless of the initial pH, although without a significant difference between the treatments. The production of organic acids by these strains was assessed for all of the initial pH values investigated, and differences between the treatments were observed. Strains UFLA03-09 and UFLA03-10 produced the same acids at different initial pH values in the culture medium. There was no correlation between phosphorus solubilized from Ca3(PO4)2 in NBRIP liquid medium and the concentration of total organic acids at the different initial pH values. Therefore, the initial pH of the culture medium influences the production of organic acids by the strains UFLA03-08, UFLA03-09, UFLA03-10 and UFLA03-106 but it does not affect calcium phosphate solubilization. PMID:26273251

  17. Acidic duodenal pH alters gene expression in the cystic fibrosis mouse pancreas.

    PubMed

    Kaur, Simran; Norkina, Oxana; Ziemer, Donna; Samuelson, Linda C; De Lisle, Robert C

    2004-08-01

    The duodenum is abnormally acidic in cystic fibrosis (CF) due to decreased bicarbonate ion secretion that is dependent on the CF gene product CFTR. In the CFTR null mouse, the acidic duodenum results in increased signaling from the intestine to the exocrine pancreas in an attempt to stimulate pancreatic bicarbonate ion secretion. Excess stimulation is proposed to add to the stress/inflammation of the pancreas in CF. DNA microarray analysis of the CF mouse revealed altered pancreatic gene expression characteristic of stress/inflammation. When the duodenal pH was corrected genetically (crossing CFTR null with gastrin null mice) or pharmacologically (use of the proton pump inhibitor omeprazole), expression levels of genes measured by quantitative RT-PCR were significantly normalized. It is concluded that the acidic duodenal pH in CF contributes to the stress on the exocrine pancreas and that normalizing duodenal pH reduces this stress.

  18. Ammonia Catalyzed Formation of Sulfuric Acid in Troposphere: The Curious Case of A Base Promoting Acid Rain.

    PubMed

    Bandyopadhyay, Biman; Kumar, Pradeep; Biswas, Partha

    2017-04-03

    Electronic structure calculations have been performed to investigate the role of ammonia in catalyzing the formation of sulfuric acid through hydrolysis of SO3 in Earth's atmosphere. The uncatalyzed process involves a high activation barrier and, till date, is mainly known to occur in Earth's atmosphere only when catalyzed by water and acids. Here we show that hydrolysis of SO3 can be very efficiently catalyzed by ammonia, the most abundant basic component in Earth's atmosphere. It was found, based on magnitude of relative potential energies as well as rate coefficients, that ammonia is the best among all the catalysts studied until now (water and acids) and could be a considerable factor in formation of sulfuric acid in troposphere. The calculated rate coefficient (at 298 K) of ammonia catalyzed reaction has been found to be ~10^5 - 10^7 times greater than that for water catalyzed ones. It was found, based on relative rates of ammonia and water catalyzed processes that in troposphere ammonia, together with water, could be the key factor in determining the rate of formation of sulfuric acid. In fact ammonia could surpass water in catalyzing formation of sulfuric acid via hydrolysis of SO3 at various altitudes in troposphere depending upon their relative concentrations.

  19. Influence of acidic pH on hydrogen and acetate production by an electrosynthetic microbiome

    DOE PAGES

    LaBelle, Edward V.; Marshall, Christopher W.; Gilbert, Jack A.; ...

    2014-10-15

    Production of hydrogen and organic compounds by an electrosynthetic microbiome using electrodes and carbon dioxide as sole electron donor and carbon source, respectively, was examined after exposure to acidic pH (~5). Hydrogen production by biocathodes poised at -600 mV vs. SHE increased>100-fold and acetate production ceased at acidic pH, but ~5–15 mM (catholyte volume)/day acetate and>1,000 mM/day hydrogen were attained at pH ~6.5 following repeated exposure to acidic pH. Cyclic voltammetry revealed a 250 mV decrease in hydrogen overpotential and a maximum current density of 12.2 mA/cm2 at -765 mV (0.065 mA/cm2 sterile control at -800 mV) by the Acetobacterium-dominatedmore » community. Supplying -800 mV to the microbiome after repeated exposure to acidic pH resulted in up to 2.6 kg/m3/day hydrogen (≈2.6 gallons gasoline equivalent), 0.7 kg/m3/day formate, and 3.1 kg/m3/day acetate ( = 4.7 kg CO2 captured).« less

  20. Influence of acidic pH on hydrogen and acetate production by an electrosynthetic microbiome

    SciTech Connect

    LaBelle, Edward V.; Marshall, Christopher W.; Gilbert, Jack A.; May, Harold D.; Battista, John R.

    2014-10-15

    Production of hydrogen and organic compounds by an electrosynthetic microbiome using electrodes and carbon dioxide as sole electron donor and carbon source, respectively, was examined after exposure to acidic pH (~5). Hydrogen production by biocathodes poised at -600 mV vs. SHE increased>100-fold and acetate production ceased at acidic pH, but ~5–15 mM (catholyte volume)/day acetate and>1,000 mM/day hydrogen were attained at pH ~6.5 following repeated exposure to acidic pH. Cyclic voltammetry revealed a 250 mV decrease in hydrogen overpotential and a maximum current density of 12.2 mA/cm2 at -765 mV (0.065 mA/cm2 sterile control at -800 mV) by the Acetobacterium-dominated community. Supplying -800 mV to the microbiome after repeated exposure to acidic pH resulted in up to 2.6 kg/m3/day hydrogen (≈2.6 gallons gasoline equivalent), 0.7 kg/m3/day formate, and 3.1 kg/m3/day acetate ( = 4.7 kg CO2 captured).

  1. Influence of Acidic pH on Hydrogen and Acetate Production by an Electrosynthetic Microbiome

    PubMed Central

    LaBelle, Edward V.; Marshall, Christopher W.; Gilbert, Jack A.; May, Harold D.

    2014-01-01

    Production of hydrogen and organic compounds by an electrosynthetic microbiome using electrodes and carbon dioxide as sole electron donor and carbon source, respectively, was examined after exposure to acidic pH (∼5). Hydrogen production by biocathodes poised at −600 mV vs. SHE increased>100-fold and acetate production ceased at acidic pH, but ∼5–15 mM (catholyte volume)/day acetate and>1,000 mM/day hydrogen were attained at pH ∼6.5 following repeated exposure to acidic pH. Cyclic voltammetry revealed a 250 mV decrease in hydrogen overpotential and a maximum current density of 12.2 mA/cm2 at −765 mV (0.065 mA/cm2 sterile control at −800 mV) by the Acetobacterium-dominated community. Supplying −800 mV to the microbiome after repeated exposure to acidic pH resulted in up to 2.6 kg/m3/day hydrogen (≈2.6 gallons gasoline equivalent), 0.7 kg/m3/day formate, and 3.1 kg/m3/day acetate ( = 4.7 kg CO2 captured). PMID:25333313

  2. Transcriptome Profiling of Shewanella oneidensis Gene Expressionfollowing Exposure to Acidic and Alkaline pH

    SciTech Connect

    Leaphart, Adam B.; Thompson, Dorothea K.; Huang, Katherine; Alm,Eric; Wan, Xiu-Feng; Arkin, Adam P.; Brown, Steven D.; Wu, Liyou; Yan,Tingfen; Liu, Xueduan; Wickham, Gene S.; Zhou, Jizhong

    2007-04-02

    The molecular response of Shewanella oneidensis MR-1 tovariations in extracellular pH was investigated based on genomewide geneexpression profiling. Microarray analysis revealed that cells elicitedboth general and specific transcriptome responses when challenged withenvironmental acid (pH 4) or base (pH 10) conditions over a 60-minperiod. Global responses included the differential expression of genesfunctionally linked to amino acid metabolism, transcriptional regulationand signal transduction, transport, cell membrane structure, andoxidative stress protection. Response to acid stress included theelevated expression of genes encoding glycogen biosynthetic enzymes,phosphate transporters, and the RNA polymerase sigma-38 factor (rpoS),whereas the molecular response to alkaline pH was characterized byupregulation of nhaA and nhaR, which are predicted to encode an Na+/H+antiporter and transcriptional activator, respectively, as well assulfate transport and sulfur metabolism genes. Collectively, theseresults suggest that S. oneidensis modulates multiple transporters, cellenvelope components, and pathways of amino acid consumption and centralintermediary metabolism as part of its transcriptome response to changingexternal pH conditions.

  3. Influence of pH on organic acid production by Clostridium sporogenes in test tube and fermentor cultures.

    PubMed Central

    Montville, T J; Parris, N; Conway, L K

    1985-01-01

    The influence of pH on the growth parameters of and the organic acids produced by Clostridium sporogenes 3121 cultured in test tubes and fermentors at 35 degrees C was examined. Specific growth rates in the fermentor maintained at a constant pH ranged from 0.20 h-1 at pH 5.00 to 0.86 h-1 at pH 6.50. Acetic acid was the primary organic acid in supernatants of 24-h cultures; total organic acid levels were 2.0 to 22.0 mumol/ml. Supernatants from pH 5.00 and 5.50 cultures had total organic acid levels less than one-third of those found at pH 6.00 to 7.00. The specific growth rates of the test tube cultures ranged from 0.51 h-1 at pH 5.00 to 0.95 h-1 at pH 6.50. The pH of the medium did not affect the average total organic acid content (51.5 mumol/ml) but did affect the distribution of the organic acids, which included formic, acetic, propionic, butyric, 3-(p-hydroxyphenyl)propionic, and 3-phenylpropionic acids. Butyric acid levels were lower, but formic and propionic acid levels were higher, at pH 5.00 than at other pHs. PMID:4004207

  4. Effects of saliva on starch-thickened drinks with acidic and neutral pH.

    PubMed

    Hanson, Ben; Cox, Ben; Kaliviotis, Efstathios; Smith, Christina H

    2012-09-01

    Powdered maize starch thickeners are used to modify drink consistency in the clinical management of dysphagia. Amylase is a digestive enzyme found in saliva which breaks down starch. This action is dependent on pH, which varies in practice depending on the particular drink. This study measured the effects of human saliva on the viscosity of drinks thickened with a widely used starch-based thickener. Experiments simulated a possible clinical scenario whereby saliva enters a cup and contaminates a drink. Citric acid (E330) was added to water to produce a controlled range of pH from 3.0 to 7.0, and several commercially available drinks with naturally low pH were investigated. When saliva was added to thickened water, viscosity was reduced to less than 1% of its original value after 10-15 min. However, lowering pH systematically slowed the reduction in viscosity attributable to saliva. At pH 3.5 and below, saliva was found to have no significant effect on viscosity. The pH of drinks in this study ranged from 2.6 for Coca Cola to 6.2 for black coffee. Again, low pH slowed the effect of saliva. For many popular drinks, having pH of 3.6 or less, viscosity was not significantly affected by the addition of saliva.

  5. Effects of Liming on Forage Availability and Nutrient Content in a Forest Impacted by Acid Rain

    PubMed Central

    Pabian, Sarah E.; Ermer, Nathan M.; Tzilkowski, Walter M.; Brittingham, Margaret C.

    2012-01-01

    Acidic deposition and subsequent forest soil acidification and nutrient depletion can affect negatively the growth, health and nutrient content of vegetation, potentially limiting the availability and nutrient content of forage for white-tailed deer (Odocoileus virginianus) and other forest herbivores. Liming is a mitigation technique that can be used to restore forest health in acidified areas, but little is known about how it affects the growth or nutrient content of deer forage. We examined the effects of dolomitic limestone application on the growth and chemical composition of understory plants in an acidified forest in central Pennsylvania, with a focus on vegetative groups included as white-tailed deer forage. We used a Before-After-Control-Impact study design with observations 1 year before liming and up to 5 years post-liming on 2 treated and 2 untreated 100-ha sites. Before liming, forage availability and several nutrients were below levels considered optimal for white-tailed deer, and many vegetative characteristics were related to soil chemistry. We observed a positive effect of liming on forb biomass, with a 2.7 fold increase on limed sites, but no biomass response in other vegetation groups. We observed positive effects of liming on calcium and magnesium content and negative effects on aluminum and manganese content of several plant groups. Responses to liming by forbs and plant nutrients show promise for improving vegetation health and forage quality and quantity for deer. PMID:22761890

  6. Effects of liming on forage availability and nutrient content in a forest impacted by acid rain.

    PubMed

    Pabian, Sarah E; Ermer, Nathan M; Tzilkowski, Walter M; Brittingham, Margaret C

    2012-01-01

    Acidic deposition and subsequent forest soil acidification and nutrient depletion can affect negatively the growth, health and nutrient content of vegetation, potentially limiting the availability and nutrient content of forage for white-tailed deer (Odocoileus virginianus) and other forest herbivores. Liming is a mitigation technique that can be used to restore forest health in acidified areas, but little is known about how it affects the growth or nutrient content of deer forage. We examined the effects of dolomitic limestone application on the growth and chemical composition of understory plants in an acidified forest in central Pennsylvania, with a focus on vegetative groups included as white-tailed deer forage. We used a Before-After-Control-Impact study design with observations 1 year before liming and up to 5 years post-liming on 2 treated and 2 untreated 100-ha sites. Before liming, forage availability and several nutrients were below levels considered optimal for white-tailed deer, and many vegetative characteristics were related to soil chemistry. We observed a positive effect of liming on forb biomass, with a 2.7 fold increase on limed sites, but no biomass response in other vegetation groups. We observed positive effects of liming on calcium and magnesium content and negative effects on aluminum and manganese content of several plant groups. Responses to liming by forbs and plant nutrients show promise for improving vegetation health and forage quality and quantity for deer.

  7. Development of Online Spectroscopic pH Monitoring for Nuclear Fuel Reprocessing Plants: Weak Acid Schemes.

    PubMed

    Casella, Amanda J; Ahlers, Laura R H; Campbell, Emily L; Levitskaia, Tatiana G; Peterson, James M; Smith, Frances N; Bryan, Samuel A

    2015-05-19

    In nuclear fuel reprocessing, separating trivalent minor actinides and lanthanide fission products is extremely challenging and often necessitates tight pH control in TALSPEAK (Trivalent Actinide-Lanthanide Separation by Phosphorus reagent Extraction from Aqueous Komplexes) separations. In TALSPEAK and similar advanced processes, aqueous pH is one of the most important factors governing the partitioning of lanthanides and actinides between an aqueous phase containing a polyaminopolycarboxylate complexing agent and a weak carboxylic acid buffer and an organic phase containing an acidic organophosphorus extractant. Real-time pH monitoring would significantly increase confidence in the separation performance. Our research is focused on developing a general method for online determination of the pH of aqueous solutions through chemometric analysis of Raman spectra. Spectroscopic process-monitoring capabilities, incorporated in a counter-current centrifugal contactor bank, provide a pathway for online, real-time measurement of solution pH. The spectroscopic techniques are process-friendly and can be easily configured for online applications, whereas classic potentiometric pH measurements require frequent calibration/maintenance and have poor long-term stability in aggressive chemical and radiation environments. Raman spectroscopy discriminates between the protonated and deprotonated forms of the carboxylic acid buffer, and the chemometric processing of the Raman spectral data with PLS (partial least-squares) regression provides a means to quantify their respective abundances and therefore determine the solution pH. Interpretive quantitative models have been developed and validated under a range of chemical composition and pH conditions using a lactic acid/lactate buffer system. The developed model was applied to new spectra obtained from online spectral measurements during a solvent extraction experiment using a counter-current centrifugal contactor bank. The model

  8. Optimization of pH values to formulate the bireagent kit for serum uric acid assay.

    PubMed

    Huang, Ya; Chen, Yuanxiang; Yang, Xiaolan; Zhao, Hua; Hu, Xiaolei; Pu, Jun; Liao, Juan; Long, Gaobo; Liao, Fei

    2015-01-01

    A new formulation of the bireagent kit for serum uric acid assay was developed based on the effects of pH on enzyme stability. At 4 °C, half-lives of uricases from Bacillus fastidious and Arthrobacter globiforms were longer than 15 months at pH 9.2, but became shorter at pH below 8.0; half-lives of ascorbate oxidase and peroxidase were comparable at pH 6.5 and 7.0, but became much shorter at pH higher than 7.4. In the new formulation of the bireagent kit, Reagent A contained peroxidase, 4-aminoantipyrine, and ascorbate oxidase in 50 mM phosphate buffer at pH 6.5; Reagent B contained B. fastidious or A. globiforms uricase in 50 mM sodium borate buffer at pH 9.2; Reagents A and B were mixed at 4:1 to produce a final pH from 7.2 to 7.6 for developing a stable color. The new bireagent kit consumed smaller quantities of three enzymes for the same shelf life. With the new bireagent kit, there were linear responses of absorbance at 546 nm to uric acid up to 34 mM in reaction mixtures and a good correlation of uric acid levels in clinical sera with those by a commercial kit, but stronger resistance to ascorbate. Therefore, the new formulation was advantageous.

  9. Vaginal pH and Microbicidal Lactic Acid When Lactobacilli Dominate the Microbiota

    PubMed Central

    O’Hanlon, Deirdre E.; Moench, Thomas R.; Cone, Richard A.

    2013-01-01

    Lactic acid at sufficiently acidic pH is a potent microbicide, and lactic acid produced by vaginal lactobacilli may help protect against reproductive tract infections. However, previous observations likely underestimated healthy vaginal acidity and total lactate concentration since they failed to exclude women without a lactobacillus-dominated vaginal microbiota, and also did not account for the high carbon dioxide, low oxygen environment of the vagina. Fifty-six women with low (0-3) Nugent scores (indicating a lactobacillus-dominated vaginal microbiota) and no symptoms of reproductive tract disease or infection, provided a total of 64 cervicovaginal fluid samples using a collection method that avoided the need for sample dilution and rigorously minimized aerobic exposure. The pH of samples was measured by microelectrode immediately after collection and under a physiological vaginal concentration of CO2. Commercial enzymatic assays of total lactate and total acetate concentrations were validated for use in CVF, and compared to the more usual HPLC method. The average pH of the CVF samples was 3.5 ± 0.3 (mean ± SD), range 2.8-4.2, and the average total lactate was 1.0% ± 0.2% w/v; this is a five-fold higher average hydrogen ion concentration (lower pH) and a fivefold higher total lactate concentration than in the prior literature. The microbicidal form of lactic acid (protonated lactic acid) was therefore eleven-fold more concentrated, and a markedly more potent microbicide, than indicated by prior research. This suggests that when lactobacilli dominate the vaginal microbiota, women have significantly more lactic acid-mediated protection against infections than currently believed. Our results invite further evaluations of the prophylactic and therapeutic actions of vaginal lactic acid, whether provided in situ by endogenous lactobacilli, by probiotic lactobacilli, or by products that reinforce vaginal lactic acid. PMID:24223212

  10. Vaginal pH and microbicidal lactic acid when lactobacilli dominate the microbiota.

    PubMed

    O'Hanlon, Deirdre E; Moench, Thomas R; Cone, Richard A

    2013-01-01

    Lactic acid at sufficiently acidic pH is a potent microbicide, and lactic acid produced by vaginal lactobacilli may help protect against reproductive tract infections. However, previous observations likely underestimated healthy vaginal acidity and total lactate concentration since they failed to exclude women without a lactobacillus-dominated vaginal microbiota, and also did not account for the high carbon dioxide, low oxygen environment of the vagina. Fifty-six women with low (0-3) Nugent scores (indicating a lactobacillus-dominated vaginal microbiota) and no symptoms of reproductive tract disease or infection, provided a total of 64 cervicovaginal fluid samples using a collection method that avoided the need for sample dilution and rigorously minimized aerobic exposure. The pH of samples was measured by microelectrode immediately after collection and under a physiological vaginal concentration of CO2. Commercial enzymatic assays of total lactate and total acetate concentrations were validated for use in CVF, and compared to the more usual HPLC method. The average pH of the CVF samples was 3.5 ± 0.3 (mean ± SD), range 2.8-4.2, and the average total lactate was 1.0% ± 0.2% w/v; this is a five-fold higher average hydrogen ion concentration (lower pH) and a fivefold higher total lactate concentration than in the prior literature. The microbicidal form of lactic acid (protonated lactic acid) was therefore eleven-fold more concentrated, and a markedly more potent microbicide, than indicated by prior research. This suggests that when lactobacilli dominate the vaginal microbiota, women have significantly more lactic acid-mediated protection against infections than currently believed. Our results invite further evaluations of the prophylactic and therapeutic actions of vaginal lactic acid, whether provided in situ by endogenous lactobacilli, by probiotic lactobacilli, or by products that reinforce vaginal lactic acid.

  11. Uric acid plasma level and urine pH in rats treated with ambroxol.

    PubMed

    Drewa, Tomasz; Wolski, Zbigniew; Gruszka, Marzena; Misterek, Bartosz; Lysik, Joanna

    2007-01-01

    It was a chance discovery that ambroxol parenteral administration led to urinary bladder stone formation in rats. This study was undertaken to examine the serum uric acid levels and urine pH in rats after ambroxol parenteral treatment. Ambroxol influence on the uric acid level was measured in 5 rats (Rattus sp.) treated with 60 mg/kg (dissolved in injection water, sc, daily) during 2 weeks. Ambroxol influence on urine pH was examined on 45 rats divided into 3 groups. Rats from the 1st and 2nd group received 30 and 60 mg/kg/24h ambroxol, respectively. Urine was collected once daily and measured with strip kit. All values were presented as the means with standard deviations. The Student t test was used to compare the means, p < 0.05 was considered as significant. Dynamics of pH changes was measured in 4 rats treated with 60 mg/kg/24h of ambroxol. Controls received 1 mL of injection water sc. Serum uric acid level increased up to 8.7 +/- 1.0 mg/dL vs. 5.7 +/- 1.0 mg/dL in control (p < 0.002). In the 1st and 2nd group urine pH increased up to 7.5 +/- 0.5 and 7.6 +/- 0.5 vs. 6.7 +/- 0.4 (p < 0.05). Ambroxol withdrawal resulted in sequential urine pH decrease. 11 days after interruption of ambroxol therapy pH reached the starting value. Urine pH changes and possible disturbances in uric acid metabolic pathway may influence on the stone formation in rats after ambroxol parenteral treatment. The influence of ambroxol on urinary tract GAG layer and the balance between xanthine and CaOx in the urine should be checked.

  12. Nestedness in Arbuscular Mycorrhizal Fungal Communities along Soil pH Gradients in Early Primary Succession: Acid-Tolerant Fungi Are pH Generalists.

    PubMed

    Kawahara, Ai; An, Gi-Hong; Miyakawa, Sachie; Sonoda, Jun; Ezawa, Tatsuhiro

    2016-01-01

    Soil acidity is a major constraint on plant productivity. Arbuscular mycorrhizal (AM) fungi support plant colonization in acidic soil, but soil acidity also constrains fungal growth and diversity. Fungi in extreme environments generally evolve towards specialists, suggesting that AM fungi in acidic soil are acidic-soil specialists. In our previous surveys, however, some AM fungi detected in strongly acidic soils could also be detected in a soil with moderate pH, which raised a hypothesis that the fungi in acidic soils are pH generalists. To test the hypothesis, we conducted a pH-manipulation experiment and also analyzed AM fungal distribution along a pH gradient in the field using a synthesized dataset of the previous and recent surveys. Rhizosphere soils of the generalist plant Miscanthus sinensis were collected both from a neutral soil and an acidic soil, and M. sinensis seedlings were grown at three different pH. For the analysis of field communities, rhizosphere soils of M. sinensis were collected from six field sites across Japan, which covered a soil pH range of 3.0-7.4, and subjected to soil trap culture. AM fungal community compositions were determined based on LSU rDNA sequences. In the pH-manipulation experiment the acidification of medium had a significant impact on the compositions of the community from the neutral soil, but the neutralization of the medium had no effect on those of the community from the acidic soil. Furthermore, the communities in lower -pH soils were subsets of (nested in) those in higher-pH soils. In the field communities a significant nestedness pattern was observed along the pH gradient. These observations suggest that the fungi in strongly acidic soils are pH generalists that occur not only in acidic soil but also in wide ranges of soil pH. Nestedness in AM fungal community along pH gradients may have important implications for plant community resilience and early primary succession after disturbance in acidic soils.

  13. Nestedness in Arbuscular Mycorrhizal Fungal Communities along Soil pH Gradients in Early Primary Succession: Acid-Tolerant Fungi Are pH Generalists

    PubMed Central

    Kawahara, Ai; An, Gi-Hong; Miyakawa, Sachie; Sonoda, Jun

    2016-01-01

    Soil acidity is a major constraint on plant productivity. Arbuscular mycorrhizal (AM) fungi support plant colonization in acidic soil, but soil acidity also constrains fungal growth and diversity. Fungi in extreme environments generally evolve towards specialists, suggesting that AM fungi in acidic soil are acidic-soil specialists. In our previous surveys, however, some AM fungi detected in strongly acidic soils could also be detected in a soil with moderate pH, which raised a hypothesis that the fungi in acidic soils are pH generalists. To test the hypothesis, we conducted a pH-manipulation experiment and also analyzed AM fungal distribution along a pH gradient in the field using a synthesized dataset of the previous and recent surveys. Rhizosphere soils of the generalist plant Miscanthus sinensis were collected both from a neutral soil and an acidic soil, and M. sinensis seedlings were grown at three different pH. For the analysis of field communities, rhizosphere soils of M. sinensis were collected from six field sites across Japan, which covered a soil pH range of 3.0–7.4, and subjected to soil trap culture. AM fungal community compositions were determined based on LSU rDNA sequences. In the pH-manipulation experiment the acidification of medium had a significant impact on the compositions of the community from the neutral soil, but the neutralization of the medium had no effect on those of the community from the acidic soil. Furthermore, the communities in lower -pH soils were subsets of (nested in) those in higher-pH soils. In the field communities a significant nestedness pattern was observed along the pH gradient. These observations suggest that the fungi in strongly acidic soils are pH generalists that occur not only in acidic soil but also in wide ranges of soil pH. Nestedness in AM fungal community along pH gradients may have important implications for plant community resilience and early primary succession after disturbance in acidic soils. PMID

  14. Changes in soil pH across England and Wales in response to decreased acid deposition

    NASA Astrophysics Data System (ADS)

    Kirk, G. J. D.; Bellamy, P. H.

    2009-04-01

    In our recent analysis of data from the National Soil Inventory of England and Wales, we found widespread changes in soil pH across both countries between the two samplings of the Inventory. In general, soil pH increased - i.e. soils became less acid - under all land uses. The Inventory was first sampled in 1978-83 on a 5-km grid over the whole area. This yielded about 6,000 sites of which 5,662 could be sampled for soil. Roughly 40% of the sites were re-sampled at intervals from 12 to 25 years after the original sampling - in 1994/96 for agricultural land and in 2002/03 for non-agricultural. Exactly the same sampling and analytical protocols were used in the two samplings. In arable soils, the increase in pH was right across the range, whereas in grassland soils the main increase was at the acid end of the scale (pH < 5.5) with a small increase above pH 7. Some part of the change is likely to have been due to changes in land management. This includes better targeting of agricultural lime on acid soils; changes in nitrogen fertilizer use; deeper ploughing bringing up more calcareous subsoil on soils on calcareous materials; and so forth. However a major driver appears to have been decreased acid deposition to land. The total amounts of nitrogen compounds deposited were relatively unchanged over the survey period, but the amounts of acidifying sulphur compounds decreased by approximately 50%. We constructed a linear regression model to assess the relation between the rate of change in pH (normalised to an annual basis) and the rate of change in acid deposition, as modified by soil properties (pH, clay content, organic matter content), rainfall and past acid deposition. We used data on rainfall and acid deposition over the survey period on the same 5-km grid as the NSI data. We fitted the model separately for each land use category. The results for arable land showed a significant effect of the change in rate of acid deposition, though a significant part of the

  15. A new boronic acid fluorescent sensor based on fluorene for monosaccharides at physiological pH

    NASA Astrophysics Data System (ADS)

    Hosseinzadeh, Rahman; Mohadjerani, Maryam; Pooryousef, Mona; Eslami, Abbas; Emami, Saeed

    2015-06-01

    Fluorescent boronic acids are very useful fluorescent sensor for detection of biologically important saccharides. Herein we synthesized a new fluorene-based fluorescent boronic acid that shows significant fluorescence changes upon addition of saccharides at physiological pH. Upon addition of fructose, sorbitol, glucose, galactose, ribose, and maltose at different concentration to the solution of 7-(dimethylamino)-9,9-dimethyl-9H-fluoren-2-yl-2-boronic acid (7-DMAFBA, 1), significant decreases in fluorescent intensity were observed. It was found that this boronic acid has high affinity (Ka = 3582.88 M-1) and selectivity for fructose over glucose at pH = 7.4. The sensor 1 showed a linear response toward D-fructose in the concentrations ranging from 2.5 × 10-5 to 4 × 10-4 mol L-1 with the detection limit of 1.3 × 10-5 mol L-1.

  16. Characterization and evaluation of acid rain in East Central Florida from 1978 to 1987: Ten year summary report

    NASA Technical Reports Server (NTRS)

    Madsen, Brooks C.; Dreschel, Thomas W.; Hinkle, C. Ross

    1989-01-01

    Rainfall was collected on the University of Central Florida (UCF) campus near Orlando since July 1977 and at the Kennedy Space Center (KSC), Florida since August 1977. Since November 1983, the KSC site has been affiliated with the National Atmospheric Deposition Network. Annual volume weighted pH was slightly above the 10 year mean of 4.58 during four of the past five years. Nitrate concentrations have risen somewhat during recent years while excess sulfate concentrations have remained below the 10 year mean during four of the past years. These observations hold for both the UCF and KSC data. The distribution of individual sample pH was nearly identical at UCF and KSC. Stepwise regression suggests that sulfate, nitrate, ammonium ion, and calcium play major roles in the description of rainwater acidity. Annual acid deposition and annual rainfall have varied from 30 to 50 meq/m2-yr and 100 to 180 cm/yr, respectively. Sea salt comprises about 25 percent (UCF) and greater than 50 percent (KSC) of total ionic composition.

  17. Polyamine/salt-assembled microspheres coated with hyaluronic acid for targeting and pH sensing.

    PubMed

    Zhang, Pan; Yang, Hui; Wang, Guojun; Tong, Weijun; Gao, Changyou

    2016-06-01

    The poly(allylamine hydrochloride)/trisodium citrate aggregates were fabricated and further covalently crosslinked via the coupling reaction of carboxylic sites on trisodium citrate with the amine groups on polyamine, onto which poly-L-lysine and hyaluronic acid were sequentially assembled, forming stable microspheres. The pH sensitive dye and pH insensitive dye were further labeled to enable the microspheres with pH sensing property. Moreover, these microspheres could be specifically targeted to HeLa tumor cells, since hyaluronic acid can specifically recognize and bind to CD44, a receptor overexpressed on many tumor cells. Quantitative pH measurement by confocal laser scanning microscopy demonstrated that the microspheres were internalized into HeLa cells, and accumulated in acidic compartments. By contrast, only a few microspheres were adhered on the NIH 3T3 cells surface. The microspheres with combined pH sensing property and targeting ability can enhance the insight understanding of the targeted drug vehicles trafficking after cellular internalization.

  18. Dissolved Divalent Metal and pH Effects on Amino Acid Polymerization: A Thermodynamic Evaluation.

    PubMed

    Kitadai, Norio

    2017-03-01

    Polymerization of amino acids is a fundamentally important step for the chemical evolution of life. Nevertheless, its response to changing environmental conditions has not yet been well understood because of the lack of reliable quantitative information. For thermodynamics, detailed prediction over diverse combinations of temperature and pH has been made only for a few amino acid-peptide systems. This study used recently reported thermodynamic dataset for the polymerization of the simplest amino acid "glycine (Gly)" to its short peptides (di-glycine and tri-glycine) to examine chemical and structural characteristics of amino acids and peptides that control the temperature and pH dependence of polymerization. Results showed that the dependency is strongly controlled by the intramolecular distance between the amino and carboxyl groups in an amino acid structure, although the side-chain group role is minor. The polymerization behavior of Gly reported earlier in the literature is therefore expected to be a typical feature for those of α-amino acids. Equilibrium calculations were conducted to examine effects of dissolved metals as a function of pH on the monomer-polymer equilibria of Gly. Results showed that metals shift the equilibria toward the monomer side, particularly at neutral and alkaline pH. Metals that form weak interaction with Gly (e.g., Mg(2+)) have no noticeable influence on the polymerization, although strong interaction engenders significant decrease of the equilibrium concentrations of Gly peptides. Considering chemical and structural characteristics of Gly and Gly peptides that control their interactions with metals, it can be expected that similar responses to the addition of metals are applicable in the polymerization of neutral α-amino acids. Neutral and alkaline aqueous environments with dissolved metals having high affinity with neutral α-amino acids (e.g., Cu(2+)) are therefore not beneficial places for peptide bond formation on the primitive

  19. Dissolved Divalent Metal and pH Effects on Amino Acid Polymerization: A Thermodynamic Evaluation

    NASA Astrophysics Data System (ADS)

    Kitadai, Norio

    2017-03-01

    Polymerization of amino acids is a fundamentally important step for the chemical evolution of life. Nevertheless, its response to changing environmental conditions has not yet been well understood because of the lack of reliable quantitative information. For thermodynamics, detailed prediction over diverse combinations of temperature and pH has been made only for a few amino acid-peptide systems. This study used recently reported thermodynamic dataset for the polymerization of the simplest amino acid "glycine (Gly)" to its short peptides (di-glycine and tri-glycine) to examine chemical and structural characteristics of amino acids and peptides that control the temperature and pH dependence of polymerization. Results showed that the dependency is strongly controlled by the intramolecular distance between the amino and carboxyl groups in an amino acid structure, although the side-chain group role is minor. The polymerization behavior of Gly reported earlier in the literature is therefore expected to be a typical feature for those of α-amino acids. Equilibrium calculations were conducted to examine effects of dissolved metals as a function of pH on the monomer-polymer equilibria of Gly. Results showed that metals shift the equilibria toward the monomer side, particularly at neutral and alkaline pH. Metals that form weak interaction with Gly (e.g., Mg2+) have no noticeable influence on the polymerization, although strong interaction engenders significant decrease of the equilibrium concentrations of Gly peptides. Considering chemical and structural characteristics of Gly and Gly peptides that control their interactions with metals, it can be expected that similar responses to the addition of metals are applicable in the polymerization of neutral α-amino acids. Neutral and alkaline aqueous environments with dissolved metals having high affinity with neutral α-amino acids (e.g., Cu2+) are therefore not beneficial places for peptide bond formation on the primitive

  20. pH responsive poly amino-acid hydrogels formed via silk sericin templating.

    PubMed

    Kurland, Nicholas E; Ragland, Robert B; Zhang, Aolin; Moustafa, Mahmoud E; Kundu, Subhas C; Yadavalli, Vamsi K

    2014-09-01

    Poly(amino acid) hydrogels have attracted a great deal of attention as biodegradable biomaterials that can limit products of synthetic polymer degradation. Here we report on a stimuli-responsive, porous, composite biomaterial based on the protein templating of the poly(amino acid) hydrogel from poly(aspartic acid) with the silk protein sericin. This low-cost, biocompatible and biodegradable hydrogel demonstrates a greatly increased porosity and improvement in volumetric swelling over networks formed from pure poly(aspartic acid). The swelling capacity measured over a range of pH values surrounding physiological pH 7.0 demonstrates a linear profile, in which hydrogel volume and mass increase to a maximum, with an increase as a function of higher sericin content. In comparison to pure poly(aspartic acid), this demonstrates a nearly 3-fold increase in retention volume at basic pH. The increase in swelling is also demonstrated by the increase in porosity and internal micro-architecture of the hydrogel networks. The biomaterial is then shown to perform well as a scaffold for cells with high mechanical strength and integrity. This protein- and homo poly(amino acid)-based super-swelling hydrogel has applications in drug delivery and tissue engineering as an economical and environmentally friendly biomaterial, in addition to ensuring the species incorporated maintain their biocompatibility during processing.

  1. Influence of sodium chloride, pH, and lactic acid bacteria on anaerobic lactic acid utilization during fermented cucumber spoilage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cucumbers are preserved commercially by natural fermentations in 5% to 8% sodium chloride (NaCl) brines. Occasionally, fermented cucumbers spoil after the primary fermentation is complete. This spoilage has been characterized by decreases in lactic acid and a rise in brine pH caused by microbial ins...

  2. Similar bacterial community composition in acidic mining lakes with different pH and lake chemistry.

    PubMed

    Kampe, Heike; Dziallas, Claudia; Grossart, Hans-Peter; Kamjunke, Norbert

    2010-10-01

    As extreme environmental conditions strongly affect bacterial community composition (BCC), we examined whether differences in pH-even at low pH-and in iron and sulfate concentrations lead to changes in BCC of acidic mining lakes. Thereby, we tested the following hypotheses: (1) diversity of the bacterial community in acidic lakes decreases with reducing pH, (2) BCC differs between epilimnion and hypolimnion, and (3) BCC in extremely acidic environments does not vary much over time. Therefore, we investigated the BCC of three acidic lakes with different pH values (2.3, 2.7, and 3.2) by denaturing gradient gel electrophoresis (DGGE) and subsequent sequencing of DGGE bands as well as catalyzed reporter deposition-FISH (CARD-FISH). BCC did not significantly vary among the studied lakes nor differ much between water layers. In contrast, BCC significantly changed over time, which is contradictory to our hypotheses. Bacterial communities were dominated by Alpha-, Beta-, and Gammaproteobacteria, whereas Actino- and Acidobacteria rarely occurred. Cell numbers of both free and attached bacteria were positively related to DOC concentration. Overall, low pH and extreme chemical conditions of the studied lakes led to similar assemblages of bacteria with pronounced temporal differences. This notion indicates that temporal changes in environmental conditions including food web structure also affect unique communities of bacteria thriving at low pH.

  3. A colorimetric pH indicators and boronic acids ensemble array for quantitative sugar analysis.

    PubMed

    Ghosh, Krishna Kanta; Yap, Eunice; Kim, Hanjo; Lee, Jun-Seok; Chang, Young-Tae

    2011-04-07

    The colorimetric response patterns of pH indicators and boronic acids ensemble array were used to analyze serial concentrations of mono-, disaccharides quantitatively. Furthermore, this ensemble array was successfully applied to quantify the sugar content in clinically used saline solutions.

  4. Autoinducer-2 detection among commensal oral streptococci is dependent on pH and boric acid.

    PubMed

    Cuadra, Giancarlo A; Frantellizzi, Ashley J; Gaesser, Kimberly M; Tammariello, Steven P; Ahmed, Anika

    2016-07-01

    Autoinducer-2, considered a universal signaling molecule, is produced by many species of bacteria; including oral strains. Structurally, autoinducer-2 can exist bound to boron (borated autoinducer-2). Functionally, autoinducer-2 has been linked to important bacterial processes such as virulence and biofilm formation. In order to test production of autoinducer-2 by a given bacterial strain, a bioassay using marine bioluminescent bacteria Vibrio harveyi as a reporter for autoinducer-2 has been designed. We hypothesize that pH adjustment and addition of boron are required for optimal bioluminescence and accurate autoinducer-2 detection. Using this reporter strain we tested autoinducer-2 activity from two oral commensal species, Streptococcus gordonii DL1 and Streptococcus oralis 34. Spent broth was collected and adjusted to pH 7.5 and supplemented with boric acid prior to measuring autoinducer- 2 activity. Results show that low pH inhibits bioluminescence of the reporter strain, but pH 7.5 allows for bioluminescence induction and proper readings of autoinducer-2 activity. Addition of boric acid also has a positive effect on bioluminescence allowing for a more sensitive detection of autoinducer-2 activity. Our data suggests that although autoinducer-2 is present in spent broth, low pH and/or low levels of boric acid become an obstacle for proper autoinducer-2 detection. For proper autoinducer-2 detection, we propose a protocol using this bioassay to include pH adjustment and boric acid addition to spent broth. Studies on autoinducer-2 activity in several bacteria species represent an important area of study as this universal signaling molecule is involved in critical bacterial phenotypes such as virulence and biofilm formation.

  5. [Effect of pH and fermentation time on yield and optical purity of lactic acid from kitchen wastes fermentation].

    PubMed

    Zhang, Bo; He, Pin-Jing; Shao, Li-Ming

    2007-04-01

    Batch experiments were carried out to analyze the effect of pH and fermentation time on the yield of total lactic acid and the distribution of L- and D-lactic acid among total lactic acid during the non-sterilized fermentation of kitchen wastes. The results show that the concentration of reduced sugar (calculated as organic carbon) is low, and its concentration was higher at neutral and alkali conditions (pH 6 - 8) than at acidic conditions (non-controlled pH and pH = 5). The maximum total lactic acid production rate and yield is 0.59 g x (L x h)(-1) and 0.62 g per gram VS at pH 7, respectively. The proportion of lactic acid (calculated as organic carbon) among the TOC reaches 78% and 89% at controlled pH 7 and 8, respectively. The L-lactic acid is the predominant isomer form at pH 8. Lactic acid concentration depends on pH, fermentation time and interaction from the response surface analysis. pH and fermentation time have a significant effect on the optical purity of lactic acid. At acidic conditions, the ratio of L-lactic acid to the total lactic acid increases with the fermentation time before 120 h, and the ratio reaches 0.9 at 120 h. At alkaline conditions, the ratio keeps at above 0.86 in the whole experimental fermentation time and reachs the maximum value (0.93) at 48 h. It decreases with fermentation time at pH 7. To obtain high lactic acid yield and optical purity simultaneously, it is suggested that pH should be contralled at 8.

  6. Unraveling the Role of Sulfur Compounds in Acid Rain Formation: Experiments on a Wetted Glass pH Electrode

    ERIC Educational Resources Information Center

    Lopes, Fernando S.; Coelho, Lucia H. G.; Gutz, Ivano G. R.; Vitz, Ed

    2010-01-01

    Vast quantities, on the order of megatons, of pollutants are emitted monthly to the atmosphere both by natural and anthropogenic sources. The evaluation of rainwater composition has great importance in understanding the atmospheric chemical composition, as water drops scavenge particles and soluble atmospheric pollutants. Most students are aware…

  7. Recovery of carboxylic acids at pH greater than pKa

    SciTech Connect

    Tung, Lisa A.

    1993-08-01

    Economics of producing carboxylic acids by fermentation is often dominated, not by the fermentation cost, but by the cost of recovering and purifying the acids from dilute aqueous solutions. Experiments were performed to measure uptakes of lactic and succinic acids as functions of pH by basic polymeric sorbents; sorbent regeneration was also tested. Performance at pH > pKa and regenerability depend on sorbent basicity; apparent pKa and monomer pK{sub a} can be used to predict sorbent performance. Two basic amine extractants, Alamine 336 and Amberlite LA-2, in were also studied; they are able to sustain capacity to higher pH in diluents that stabilize the acid-amine complex through H bonding. Secondary amines perform better than tert-amines in diluents that solvate the additional proton. Competitive sulfate and phosphate, an interference in fermentation, are taken up by sorbents more strongly than by extractants. The third step in the proposed fermentation process, the cracking of the trimethylammonium (TMA) carboxylate, was also examined. Because lactic acid is more soluble and tends to self-esterify, simple thermal cracking does not remove all TMA; a more promising approach is to esterify the TMA lactate by reaction with an alcohol.

  8. Evaluation of net acid generation pH as a single indicator for acid forming potential of rocks using geochemical properties.

    PubMed

    Oh, Chamteut; Ji, Sangwoo; Yim, Giljae; Cheong, Youngwook

    2017-04-01

    The main purpose of this research was to evaluate the geochemical properties of rocks for a single indicator of acid-forming potential. The indicators, such as net acid generation (NAG), NAG pH and total S, were applied to 312 rock samples of various geological characteristics. Additional indicators, such as a Modified NAG pH, paste pH and available acid neutralizing capacity (ANC), were applied to 22 selected samples. Among them, NAG pH was considered the most plausible single indicator in evaluating acid-forming potential, as it is simple to measure, widely applicable to various samples and can be used to estimate the NAG value. The acid-forming potential of 287 samples (92% of samples examined in this research) was classified as either non-acid forming (NAF) or potentially acid forming (PAF) by NAG pH, with an NAF criteria of <3.21 and PAF of >4.52. The NAG pH was also a good estimate of the risk of short-term acid release when combined with paste pH information. However, application of NAG pH to coal mine wastes, with high organic carbon contents, produced erroneous results due to the generation of organic acid during the NAG test. In this research, a Modified NAG pH was assessed as an alternative to NAG pH in such situations.

  9. Algal and bacterial activities in acidic (pH 3) strip mine lakes

    SciTech Connect

    Gyure, R.A.; Konopka, A.; Brooks, A.; Doemel, W.

    1987-09-01

    Reservoir 29 and Lake B are extremely acid lakes (epilimnion pHs of 2.7 and 3.2, respectively), because they receive acidic discharges from coal refuse piles. They differ in that the pH of profundal sediments in Reservoir 29 increased from 2.7 to 3.8 during the period of thermal stratification, whereas permanently anoxic sediments in Lake B had a pH of 6.2. The pH rise in Reservoir 29 sediments was correlated with a temporal increase in H/sub 2/S concentration in the anaerobic hypolimnion from 0 to >1 mM. The chlorophyll a levels in the epilimnion of Reservoir 29 were low, and the rate of primary production was typical of an oligotrophic system. However, there was a dense 10-cm layer of algal biomass at the bottom of the metalimnion. Production by this layer was low owing to light limitation and possibly H/sub 2/S toxicity. The specific photosynthetic rates of epilimnetic algae were low, which suggests that nutrient availability is more important than pH in limiting production. The highest photosynthetic rates were obtained in water samples incubated at pH 2.7 to 4. Heterotrophic bacterial activity (measured by (/sup 14/C)glucose metabolism) was greatest at the sediment/water interface. Bacterial production (assayed by thymidine incorporation) was as high in Reservoir 29 as in a nonacid mesotrophic Indiana lake.

  10. Algal and Bacterial Activities in Acidic (pH 3) Strip Mine Lakes

    PubMed Central

    Gyure, Ruth A.; Konopka, Allan; Brooks, Austin; Doemel, William

    1987-01-01

    Reservoir 29 and Lake B are extremely acid lakes (epilimnion pHs of 2.7 and 3.2, respectively), because they receive acidic discharges from coal refuse piles. They differ in that the pH of profundal sediments in Reservoir 29 increased from 2.7 to 3.8 during the period of thermal stratification, whereas permanently anoxic sediments in Lake B had a pH of 6.2. The pH rise in Reservoir 29 sediments was correlated with a temporal increase in H2S concentration in the anaerobic hypolimnion from 0 to >1 mM. The chlorophyll a levels in the epilimnion of Reservoir 29 were low, and the rate of primary production was typical of an oligotrophic system. However, there was a dense 10-cm layer of algal biomass at the bottom of the metalimnion. Production by this layer was low owing to light limitation and possibly H2S toxicity. The specific photosynthetic rates of epilimnetic algae were low, which suggests that nutrient availability is more important than pH in limiting production. The highest photosynthetic rates were obtained in water samples incubated at pH 2.7 to 4. Heterotrophic bacterial activity (measured by [14C]glucose metabolism) was greatest at the sediment/water interface. Bacterial production (assayed by thymidine incorporation) was as high in Reservoir 29 as in a nonacid mesotrophic Indiana lake. PMID:16347430

  11. ACID RAIN MODELING

    EPA Science Inventory

    This paper provides an overview of existing statistical methodologies for the estimation of site-specific and regional trends in wet deposition. The interaction of atmospheric processes and emissions tend to produce wet deposition data patterns that show large spatial and tempora...

  12. Acid Rain: Science Projects.

    ERIC Educational Resources Information Center

    Hessler, Edward W.; Stubbs, Harriett S.

    Too often science seems to be a matter of studying from books and responding to questions raised by teachers about the information either in the classroom or on examinations. Such a view of science misses its importance as a way of thinking, doing, and preparing for citizenship roles. The problems and activities included in this volume are…

  13. Acid rain: Microphysical model

    NASA Technical Reports Server (NTRS)

    Dingle, A. N.

    1980-01-01

    A microphysical model was used to simulate the case of a ground cloud without dilution by entrainment and without precipitation. The numerical integration techniques of the model are presented. The droplet size spectra versus time and the droplet molalities for each value of time are discussed.

  14. Acid rain: Mesoscale model

    NASA Technical Reports Server (NTRS)

    Hsu, H. M.

    1980-01-01

    A mesoscale numerical model of the Florida peninsula was formulated and applied to a dry, neutral atmosphere. The prospective use of the STAR-100 computer for the submesoscale model is discussed. The numerical model presented is tested under synoptically undisturbed conditions. Two cases, differing only in the direction of the prevailing geostrophic wind, are examined: a prevailing southwest wind and a prevailing southeast wind, both 6 m/sec at all levels initially.

  15. [Effects of thiourea on pH and availability of metal ions in acid red soil].

    PubMed

    Yang, Bo; Wang, Wen; Zeng, Qing-Ru; Zhou, Xi-Hong

    2014-03-01

    Through the simulation research, the effects of application of thiourea and urea on pH and availability of metal ions in acid red soil were studied, and the results showed that after applying urea, the soil pH increased in the first experimental stage and then reduced gradually to a low level, however, decreased trends of soil pH values were inhibited by the application of thiourea, especially when the concentration of thiourea reached to 5.0 mmol x kg(-1) dry soil, the soil pH was stable at high level, which exceeded to 6.0. It proved that the application of thiourea could inhibit the soil acidification due to urea application. After applying urea with different concentrations of thiourea, the available contents of Zn and Al decreased with the increasing concentration of thiourea, nevertheless, when the concentration of thiourea reached to 5.0 mmol x kg(-1), the available content of Mn was stable at high level which was over 110 mg x kg(-1). In addition, the results showed a highly significant negative correlation between the soil pH and the available content of Cu, Zn and Al, but for Mn, no discipline was found between the soil pH and the availability after applying thiourea. Moreover, the soil pH became higher after applying urea with thiourea compared to add urea only, which led to the decreasing of available content of Al, and it was benefited for the control of the phytotoxic effect of Al. The available content of Mn in the soil not only depended on soil pH but also the content of thiourea due to its redox and complexing reaction with Mn.

  16. Anoxic Biodegradation of Isosaccharinic Acids at Alkaline pH by Natural Microbial Communities

    PubMed Central

    Rout, Simon P.; Charles, Christopher J.; Doulgeris, Charalampos; McCarthy, Alan J.; Rooks, Dave J.; Loughnane, J. Paul; Laws, Andrew P.; Humphreys, Paul N.

    2015-01-01

    One design concept for the long-term management of the UK’s intermediate level radioactive wastes (ILW) is disposal to a cementitious geological disposal facility (GDF). Under the alkaline (10.0<pH>13.0) anoxic conditions expected within a GDF, cellulosic wastes will undergo chemical hydrolysis. The resulting cellulose degradation products (CDP) are dominated by α- and β-isosaccharinic acids (ISA), which present an organic carbon source that may enable subsequent microbial colonisation of a GDF. Microcosms established from neutral, near-surface sediments demonstrated complete ISA degradation under methanogenic conditions up to pH 10.0. Degradation decreased as pH increased, with β-ISA fermentation more heavily influenced than α-ISA. This reduction in degradation rate was accompanied by a shift in microbial population away from organisms related to Clostridium sporosphaeroides to a more diverse Clostridial community. The increase in pH to 10.0 saw an increase in detection of Alcaligenes aquatilis and a dominance of hydrogenotrophic methanogens within the Archaeal population. Methane was generated up to pH 10.0 with acetate accumulation at higher pH values reflecting a reduced detection of acetoclastic methanogens. An increase in pH to 11.0 resulted in the accumulation of ISA, the absence of methanogenesis and the loss of biomass from the system. This study is the first to demonstrate methanogenesis from ISA by near surface microbial communities not previously exposed to these compounds up to and including pH 10.0. PMID:26367005

  17. Microenvironmental pH measurement during sodium naproxenate dissolution in acidic medium by UV/vis imaging.

    PubMed

    Ostergaard, Jesper; Jensen, Henrik; Larsen, Susan W; Larsen, Claus; Lenke, Jim

    2014-11-01

    Variable dissolution from sodium salts of drugs containing a carboxylic acid group after passing the acidic environment of the stomach may affect oral bioavailability. The aim of the present proof of concept study was to investigate pH effects in relation to the dissolution of sodium naproxenate in 0.01M hydrochloric acid. For this purpose a UV/vis imaging-based approach capable of measuring microenvironmental pH in the vicinity of the solid drug compact as well as monitoring drug dissolution was developed. Using a pH indicating dye real-time spatially resolved measurement of pH was achieved. Sodium naproxenate, can significantly alter the local pH of the dissolution medium, is eventually neutralized and precipitates as the acidic species naproxen. The developed approach is considered useful for detailed studies of pH dependent dissolution phenomena in dissolution testing.

  18. Monomeric banana lectin at acidic pH overrules conformational stability of its native dimeric form.

    PubMed

    Khan, Javed M; Qadeer, Atiyatul; Ahmad, Ejaz; Ashraf, Raghib; Bhushan, Bharat; Chaturvedi, Sumit K; Rabbani, Gulam; Khan, Rizwan H

    2013-01-01

    Banana lectin (BL) is a homodimeric protein categorized among jacalin-related family of lectins. The effect of acidic pH was examined on conformational stability of BL by using circular dichroism, intrinsic fluorescence, 1-anilino-8-napthalene sulfonate (ANS) binding, size exclusion chromatography (SEC) and dynamic light scattering (DLS). During acid denaturation of BL, the monomerization of native dimeric protein was found at pH 2.0. The elution profile from SEC showed two different peaks (59.65 ml & 87.98 ml) at pH 2.0 while single peak (61.45 ml) at pH 7.4. The hydrodynamic radii (R h) of native BL was 2.9 nm while at pH 2.0 two species were found with R h of 1.7 and 3.7 nm. Furthermore at, pH 2.0 the secondary structures of BL remained unaltered while tertiary structure was significantly disrupted with the exposure of hydrophobic clusters confirming the existence of molten globule like state. The unfolding of BL with different subunit status was further evaluated by urea and temperature mediated denaturation to check their stability. As inferred from high Cm and ΔG values, the monomeric form of BL offers more resistance towards chemical denaturation than the native dimeric form. Besides, dimeric BL exhibited a Tm of 77°C while no loss in secondary structures was observed in monomers even up to 95°C. To the best of our knowledge, this is the first report on monomeric subunit of lectins showing more stability against denaturants than its native dimeric state.

  19. Acidic pH increases airway surface liquid viscosity in cystic fibrosis

    PubMed Central

    Tang, Xiao Xiao; Ostedgaard, Lynda S.; Hoegger, Mark J.; Moninger, Thomas O.; Karp, Philip H.; McMenimen, James D.; Choudhury, Biswa; Varki, Ajit; Stoltz, David A.; Welsh, Michael J.

    2016-01-01

    Cystic fibrosis (CF) disrupts respiratory host defenses, allowing bacterial infection, inflammation, and mucus accumulation to progressively destroy the lungs. Our previous studies revealed that mucus with abnormal behavior impaired mucociliary transport in newborn CF piglets prior to the onset of secondary manifestations. To further investigate mucus abnormalities, here we studied airway surface liquid (ASL) collected from newborn piglets and ASL on cultured airway epithelia. Fluorescence recovery after photobleaching revealed that the viscosity of CF ASL was increased relative to that of non-CF ASL. CF ASL had a reduced pH, which was necessary and sufficient for genotype-dependent viscosity differences. The increased viscosity of CF ASL was not explained by pH-independent changes in HCO3– concentration, altered glycosylation, additional pH-induced disulfide bond formation, increased percentage of nonvolatile material, or increased sulfation. Treating acidic ASL with hypertonic saline or heparin largely reversed the increased viscosity, suggesting that acidic pH influences mucin electrostatic interactions. These findings link loss of cystic fibrosis transmembrane conductance regulator–dependent alkalinization to abnormal CF ASL. In addition, we found that increasing Ca2+ concentrations elevated ASL viscosity, in part, independently of pH. The results suggest that increasing pH, reducing Ca2+ concentration, and/or altering electrostatic interactions in ASL might benefit early CF. PMID:26808501

  20. Acidic pH increases airway surface liquid viscosity in cystic fibrosis.

    PubMed

    Tang, Xiao Xiao; Ostedgaard, Lynda S; Hoegger, Mark J; Moninger, Thomas O; Karp, Philip H; McMenimen, James D; Choudhury, Biswa; Varki, Ajit; Stoltz, David A; Welsh, Michael J

    2016-03-01

    Cystic fibrosis (CF) disrupts respiratory host defenses, allowing bacterial infection, inflammation, and mucus accumulation to progressively destroy the lungs. Our previous studies revealed that mucus with abnormal behavior impaired mucociliary transport in newborn CF piglets prior to the onset of secondary manifestations. To further investigate mucus abnormalities, here we studied airway surface liquid (ASL) collected from newborn piglets and ASL on cultured airway epithelia. Fluorescence recovery after photobleaching revealed that the viscosity of CF ASL was increased relative to that of non-CF ASL. CF ASL had a reduced pH, which was necessary and sufficient for genotype-dependent viscosity differences. The increased viscosity of CF ASL was not explained by pH-independent changes in HCO3- concentration, altered glycosylation, additional pH-induced disulfide bond formation, increased percentage of nonvolatile material, or increased sulfation. Treating acidic ASL with hypertonic saline or heparin largely reversed the increased viscosity, suggesting that acidic pH influences mucin electrostatic interactions. These findings link loss of cystic fibrosis transmembrane conductance regulator-dependent alkalinization to abnormal CF ASL. In addition, we found that increasing Ca2+ concentrations elevated ASL viscosity, in part, independently of pH. The results suggest that increasing pH, reducing Ca2+ concentration, and/or altering electrostatic interactions in ASL might benefit early CF.

  1. A partly folded state of acidic fibroblast growth factor at low pH.

    PubMed

    Sanz, J M; Giménez-Gallego, G

    1997-06-01

    Acid denaturation of acidic fibroblast growth factor (aFGF) at low ionic strength was monitored by far-ultraviolet circular dichroism and intrinsic fluorescence. The two spectroscopic probes displayed non-coincident transitions, which suggested the accumulation of partly folded species around pH 4.0. Although under these conditions the fluorescence of aFGF resembled that of the unfolded form of the protein, far-ultraviolet circular dichroism and proton nuclear magnetic resonance spectra indicated the presence of persistent secondary and tertiary structure. Moreover, at pH 4.0, aFGF showed cooperative thermal denaturation and interacted weakly with the hydrophobic probe N-phenyl-1-naphthylamine, showing a relatively high level of structure that did not fit into the classical molten globule category. This intermediate is also capable of interacting with liposomes and might represent a membrane translocation-competent form.

  2. Indomethacin inhibits tetrodotoxin-resistant Na(+) channels at acidic pH in rat nociceptive neurons.

    PubMed

    Nakamura, Michiko; Jang, Il-Sung

    2016-06-01

    Non-steroidal anti-inflammatory drugs (NSAIDs) are well-known inhibitors of cyclooxygenases (COXs) and are widely used for the treatment of inflammatory pain; however several NSAIDs display COX-independent analgesic action including the inhibition of voltage-gated Na(+) channels expressed in primary afferent neurons. In the present study, we examined whether NSAIDs modulate tetrodotoxin-resistant (TTX-R) Na(+) channels and if this modulation depends on the extracellular pH. The TTX-R Na(+) currents were recorded from small-sized trigeminal ganglion neurons by using a whole-cell patch clamp technique. Among eight NSAIDs tested in this study, several drugs, including aspirin and ibuprofen, did not affect TTX-R Na(+) channels either at pH 7.4 or at pH 6.0. However, we found that indomethacin, and, to a lesser extent, ibuprofen and naproxen potently inhibited the peak amplitude of TTX-R Na(+) currents at pH 6.0. The indomethacin-induced inhibition of TTX-R Na(+) channels was more potent at depolarized membrane potentials. Indomethacin significantly shifted both the voltage-activation and voltage-inactivation relationships to depolarizing potentials at pH 6.0. Indomethacin accelerated the development of inactivation and retarded the recovery from inactivation of TTX-R Na(+) channels at pH 6.0. Given that indomethacin and several other NSAIDs could further suppress local nociceptive signals by inhibiting TTX-R Na(+) channels at an acidic pH in addition to the classical COX inhibition, these drugs could be particularly useful for the treatment of inflammatory pain.

  3. Chlorogenic acid increased 5-hydroxymethylfurfural formation when heating fructose alone or with aspartic acid at two pH levels.

    PubMed

    Zhang, Zhenhua; Zou, Yueyu; Wu, Taigang; Huang, Caihuan; Pei, Kehan; Zhang, Guangwen; Lin, Xiaohua; Bai, Weibin; Ou, Shiyi

    2016-01-01

    Chlorogenic acid (CGA) is a phenolic acid that ubiquitously exists in fruits. This work aims to investigate whether and how CGA influences HMF formation during heating fructose alone, or with an amino acid. The results showed that that CGA increased 5-hydroxymethylfurfural (HMF) formation. At pH 5.5 and 7.0, the addition of 5.0 μmol/ml CGA increased HMF formation by 49.4% and 25.2%, respectively when heating fructose alone, and by 9.0% and 16.7%, respectively when heating fructose with aspartic acid. CGA significantly increased HMF formation by promoting 3-deoxosone formation, and its conversion to HMF by inhibiting HMF elimination, especially in the Maillard reaction system. A comparison of the catalytic capacity of CGA with its six analogous compounds showed that both its di-hydroxyphenyl and carboxyl groups function in increasing HMF formation.

  4. Effects of Oxygen Availability on Acetic Acid Tolerance and Intracellular pH in Dekkera bruxellensis

    PubMed Central

    Capusoni, Claudia; Arioli, Stefania; Zambelli, Paolo; Moktaduzzaman, M.; Mora, Diego

    2016-01-01

    ABSTRACT The yeast Dekkera bruxellensis, associated with wine and beer production, has recently received attention, because its high ethanol and acid tolerance enables it to compete with Saccharomyces cerevisiae in distilleries that produce fuel ethanol. We investigated how different cultivation conditions affect the acetic acid tolerance of D. bruxellensis. We analyzed the ability of two strains (CBS 98 and CBS 4482) exhibiting different degrees of tolerance to grow in the presence of acetic acid under aerobic and oxygen-limited conditions. We found that the concomitant presence of acetic acid and oxygen had a negative effect on D. bruxellensis growth. In contrast, incubation under oxygen-limited conditions resulted in reproducible growth kinetics that exhibited a shorter adaptive phase and higher growth rates than those with cultivation under aerobic conditions. This positive effect was more pronounced in CBS 98, the more-sensitive strain. Cultivation of CBS 98 cells under oxygen-limited conditions improved their ability to restore their intracellular pH upon acetic acid exposure and to reduce the oxidative damage to intracellular macromolecules caused by the presence of acetic acid. This study reveals an important role of oxidative stress in acetic acid tolerance in D. bruxellensis, indicating that reduced oxygen availability can protect against the damage caused by the presence of acetic acid. This aspect is important for optimizing industrial processes performed in the presence of acetic acid. IMPORTANCE This study reveals an important role of oxidative stress in acetic acid tolerance in D. bruxellensis, indicating that reduced oxygen availability can have a protective role against the damage caused by the presence of acetic acid. This aspect is important for the optimization of industrial processes performed in the presence of acetic acid. PMID:27235432

  5. Relationships between the resistance of yeasts to acetic, propanoic and benzoic acids and to methyl paraben and pH.

    PubMed

    Warth, A D

    1989-07-01

    Minimum inhibitory concentrations of acetic, propanoic and benzoic acids and methyl paraben were determined at pH 3.50 for 22 isolates of 11 yeast species, differing in their resistance to preservatives. Growth in the presence of benzoic acid enhanced the resistance of yeasts to benzoic and the other weak acid preservatives, but not to methyl paraben. Resistance to acetic, propanoic and benzoic acids was strongly correlated, but was not closely related to resistance to methyl paraben. Minimum pH for growth was not related to resistance to the weak acids. The results suggest that growth in the presence of weak-acid preservatives involves a common resistance mechanism.

  6. Acid rain research. Hearing before the Subcommittee on Natural Resources, Agriculture Research and Environment of the Committee on Science and Technology, US House of Representatives, Ninety-Ninth Congress, First Session, April 3, 1985

    SciTech Connect

    Not Available

    1986-01-01

    Dr. Jessica Tuchman Matthews of the World Resources Institute and Dr. J. Christopher Bernabo of the National Acid Precipitation Assessment Program (NAPAP) were the principal witnesses at a hearing to review the budget request for acid rain research at the Environmental Protection Agency, the National Oceanic and Atmospheric Administration, and the DOE. The tandem review reflects current perceptions of acid rain as a national problem. Matthews summarized her organization's findings from a study of 11 western states, where acid rain was found to threaten valuable aquatic and timber resources. Bernabo reviewed the NAPAP program and its findings on the acidification of surface waters. At issue during the hearing was whether the data now supports taking legislative action or whether more research is in order. An appendix with additional material on the transnational aspects of acid deposition and the text of the World Resources Institute study follow the testimony.

  7. Kinetics of hyaluronan hydrolysis in acidic solution at various pH values.

    PubMed

    Tømmeraas, Kristoffer; Melander, Claes

    2008-06-01

    Hyaluronic acid (HA) was hydrolyzed using varying temperatures (40, 60, and 80 degrees C) and acid concentrations (0.0010, 0.010, 0.10, 0.50, 1.0, and 2.0 M HCl). The degradation process was monitored by determination of weight average molecular weight ( M w) by size-exclusion chromatography with online multiangle laser light scattering, refractive index, and intrinsic viscosity detectors (SEC-MALLS-RI-visc) on samples taken out continuously during the hydrolysis. SEC-MALLS-RI-visc showed that the degradation gave narrow molecular weight distributions with polydispersity indexes ( M w/ M n) of 1.3-1.7. Kinetic plots of 1/ M w versus time gave linear plots showing that acid hydrolysis of HA is a random process and that it follows a first order kinetics. For hydrolysis in HCl at 60 and 80 degrees C, it was shown that the kinetic rate constant ( k h) for the degradation depended linearly on the acid concentration. Further, the dependence of temperature on the hydrolysis in 0.1 M HCl was found to give a linear Arrhenius plot (ln k h vs 1/ T), with an activation energy ( E a) of 137 kJ/mol and Arrhenius constant ( A) of 7.86 x 10 (15) h (-1). (1)H NMR spectroscopy was used to characterize the product of extensive hydrolysis (48 h at 60 degrees C in 0.1 M HCl). No indication of de- N-acetylation of the N-acetyl glucosamine (GlcNAc) units or other byproducts were seen. Additionally, a low molecular weight HA was hydrolyzed in 0.1 M DCl for 4 h at 80 degrees C. It was shown that it was primarily the beta-(1-->4)-linkage between GlcNAc and glucuronic acid (GlcA) that was cleaved during hydrolysis at pH < p K a,GlcA. The dependence of the hydrolysis rate constant was further studied as a function of pH between -0.3 and 5. The degradation was found to be random (linear kinetic plots) over the entire pH range studied. Further, the kinetic rate constant was found to depend linearly on pH in the region -0.3 to 3. Above this pH (around the p K a of HA), the kinetic constant

  8. Investigation of pH Influence on Skin Permeation Behavior of Weak Acids Using Nonsteroidal Anti-Inflammatory Drugs.

    PubMed

    Chantasart, Doungdaw; Chootanasoontorn, Siriwan; Suksiriworapong, Jiraphong; Li, S Kevin

    2015-10-01

    As a continuing effort to understand the skin permeation behavior of weak acids and bases, the objectives of the present study were to evaluate skin permeation of nonsteroidal anti-inflammatory drugs (NSAIDs) under the influence of pH, investigate the mechanism of pH effect, and examine a previous hypothesis that the effective skin pH for drug permeation is different from donor solution pH. In vitro permeability experiments were performed in side-by-side diffusion cells with diclofenac, ibuprofen, flurbiprofen, ketoprofen, and naproxen and human skin. The donor solution pH significantly affected skin permeation of NSAIDs, whereas no effect of the receiver pH was observed. Similar to previous observations, the apparent permeability coefficient versus donor solution pH relationships deviated from the predictions (fractions of unionized NSAIDs) according to the acid/base theory. The influences of the viable epidermis barrier, polar pathway transport, ion permeation across skin, and effective skin pH were investigated. The effective pH values for skin permeation determined using the NSAIDs (weak acids) in this study were different from those obtained previously with a weak base at the same donor solution pH conditions, suggesting that the observed permeability-pH relationships could not be explained solely by possible pH differences between skin and donor solution.

  9. Preferential intracellular pH regulation represents a general pattern of pH homeostasis during acid-base disturbances in the armoured catfish, Pterygoplichthys pardalis.

    PubMed

    Harter, T S; Shartau, R B; Baker, D W; Jackson, D C; Val, A L; Brauner, C J

    2014-08-01

    Preferential intracellular pH (pHi) regulation, where pHi is tightly regulated in the face of a blood acidosis, has been observed in a few species of fish, but only during elevated blood PCO2. To determine whether preferential pHi regulation may represent a general pattern for acid-base regulation during other pH disturbances we challenged the armoured catfish, Pterygoplichthys pardalis, with anoxia and exhaustive exercise, to induce a metabolic acidosis, and bicarbonate injections to induce a metabolic alkalosis. Fish were terminally sampled 2-3 h following the respective treatments and extracellular blood pH, pHi of red blood cells (RBC), brain, heart, liver and white muscle, and plasma lactate and total CO2 were measured. All treatments resulted in significant changes in extracellular pH and RBC pHi that likely cover a large portion of the pH tolerance limits of this species (pH 7.15-7.86). In all tissues other than RBC, pHi remained tightly regulated and did not differ significantly from control values, with the exception of a decrease in white muscle pHi after anoxia and an increase in liver pHi following a metabolic alkalosis. Thus preferential pHi regulation appears to be a general pattern for acid-base homeostasis in the armoured catfish and may be a common response in Amazonian fishes.

  10. The Cytosolic pH of Individual Saccharomyces cerevisiae Cells Is a Key Factor in Acetic Acid Tolerance.

    PubMed

    Fernández-Niño, Miguel; Marquina, Maribel; Swinnen, Steve; Rodríguez-Porrata, Boris; Nevoigt, Elke; Ariño, Joaquín

    2015-11-01

    It was shown recently that individual cells of an isogenic Saccharomyces cerevisiae population show variability in acetic acid tolerance, and this variability affects the quantitative manifestation of the trait at the population level. In the current study, we investigated whether cell-to-cell variability in acetic acid tolerance could be explained by the observed differences in the cytosolic pHs of individual cells immediately before exposure to the acid. Results obtained with cells of the strain CEN.PK113-7D in synthetic medium containing 96 mM acetic acid (pH 4.5) showed a direct correlation between the initial cytosolic pH and the cytosolic pH drop after exposure to the acid. Moreover, only cells with a low initial cytosolic pH, which experienced a less severe drop in cytosolic pH, were able to proliferate. A similar correlation between initial cytosolic pH and cytosolic pH drop was also observed in the more acid-tolerant strain MUCL 11987-9. Interestingly, a fraction of cells in the MUCL 11987-9 population showed initial cytosolic pH values below the minimal cytosolic pH detected in cells of the strain CEN.PK113-7D; consequently, these cells experienced less severe drops in cytosolic pH. Although this might explain in part the difference between the two strains with regard to the number of cells that resumed proliferation, it was observed that all cells from strain MUCL 11987-9 were able to proliferate, independently of their initial cytosolic pH. Therefore, other factors must also be involved in the greater ability of MUCL 11987-9 cells to endure strong drops in cytosolic pH.

  11. Effects of acidic pH on voltage-gated ion channels in rat trigeminal mesencephalic nucleus neurons

    PubMed Central

    Han, Jin-Eon; Cho, Jin-Hwa; Choi, In-Sun; Kim, Do-Yeon

    2017-01-01

    The effects of acidic pH on several voltage-dependent ion channels, such as voltage-dependent K+ and Ca2+ channels, and hyperpolarization-gated and cyclic nucleotide-activated cation (HCN) channels, were examined using a whole-cell patch clamp technique on mechanically isolated rat mesencephalic trigeminal nucleus neurons. The application of a pH 6.5 solution had no effect on the peak amplitude of voltage-dependent K+ currents. A pH 6.0 solution slightly, but significantly inhibited the peak amplitude of voltage-dependent K+ currents. The pH 6.0 also shifted both the current-voltage and conductance-voltage relationships to the depolarization range. The application of a pH 6.5 solution scarcely affected the peak amplitude of membrane currents mediated by HCN channels, which were profoundly inhibited by the general HCN channel blocker Cs+ (1 mM). However, the pH 6.0 solution slightly, but significantly inhibited the peak amplitude of HCN-mediated currents. Although the pH 6.0 solution showed complex modulation of the current-voltage and conductance-voltage relationships, the midpoint voltages for the activation of HCN channels were not changed by acidic pH. On the other hand, voltage-dependent Ca2+ channels were significantly inhibited by an acidic pH. The application of an acidic pH solution significantly shifted the current-voltage and conductance-voltage relationships to the depolarization range. The modulation of several voltage-dependent ion channels by an acidic pH might affect the excitability of mesencephalic trigeminal nucleus neurons, and thus physiological functions mediated by the mesencephalic trigeminal nucleus could be affected in acidic pH conditions. PMID:28280415

  12. Sensitivity of greenback cutthroat trout to acidic pH and elevated aluminum

    SciTech Connect

    Woodward, D.F. ); Farag, A.M. ); Little E.E.; Steadman, B. ); Yancik, R. )

    1991-01-01

    The greenback cutthroat trout Oncorhynchus clarki stomias is a threatened subspecies native to the upper South Platte and Arkansas rivers between Denver and Fort Collins, Colorado, an area also susceptible to acid deposition. In laboratory studies, the authors exposed this subspecies to nominal pHs of 4.5-6.5 and to nominal aluminum concentrations of 0, 50, 100, and 300 {mu}g/L; the control was pH 6.5 treatment without Al. The authors used soft water that contained 1.3 mg Ca/L. Exposures of 7 days each were made for four early life stages: fertilized egg, eyed embryo, alevin, and swim-up larva. Effects were measured at the end of exposure and again after a recovery period lasting until 40 days posthatch. The alevin stage was the most sensitive: at pH 5.0 with no Al, survival was reduced by 68% and swimming duration by 76%, at pH 6.0 and 50 {mu}g Al/L, swimming duration was reduced by 62%, but survival was not affected. Reductions in whole-body concentrations of Na, K, and Ca indicated organism stress. Sodium was reduced most-about 50% in alevins exposed to pH 5.0 without Al and to pH 6.0 with 50 {mu}g Al/L. Growth and the ratio of RNA to DNA were not affected by any exposure. All responses that were affected during exposure returned to normal by 40 days posthatch. Overall, it appeared that pH 6.0 and 50 {mu}g Al/L might be detrimental to greenback cutthroat trout populations.

  13. Tetracycline adsorption on kaolinite: pH, metal cations and humic acid effects.

    PubMed

    Zhao, Yanping; Geng, Jinju; Wang, Xiaorong; Gu, Xueyuan; Gao, Shixiang

    2011-07-01

    Contamination of environmental matrixes by human and animal wastes containing antibiotics is a growing health concern. Because tetracycline is one of the most widely-used antibiotics in the world, it is important to understand the factors that influence its mobility in soils. This study investigated the effects of pH, background electrolyte cations (Li(+), Na(+), K(+), Ca(2+) and Mg(2+)), heavy metal Cu(2+) and humic acid (HA) on tetracycline adsorption onto kaolinite. Results showed that tetracycline was greatly adsorbed by kaolinite over pH 3-6, then decreased with the increase of pH, indicating that tetracycline adsorption mainly through ion exchange of cations species and complexation of zwitterions species. In the presence of five types of cations (Li(+), Na(+), K(+), Ca(2+) and Mg(2+)), tetracycline adsorption decreased in accordance with the increasing of atomic radius and valence of metal cations, which suggested that outer-sphere complexes formed between tetracycline and kaolinite, and the existence of competitor ions lead to the decreasing adsorption. The presence of Cu(2+) greatly enhanced the adsorption probably by acting as a bridge ion between tetracycline species and the edge sites of kaolinite. HA also showed a major effect on the adsorption: at pH < 6, the presence of HA increased the adsorption, while the addition of HA showed little effect on tetracycline adsorption at higher pH. The soil environmental conditions, like pH, metal cations and soil organic matter, strongly influence the adsorption behavior of tetracycline onto kaolinite and need to be considered when assessing the environmental toxicity of tetracycline.

  14. Improved volatile fatty acids anaerobic production from waste activated sludge by pH regulation: Alkaline or neutral pH?

    PubMed

    Ma, Huijun; Chen, Xingchun; Liu, He; Liu, Hongbo; Fu, Bo

    2016-02-01

    In this study, the anaerobic fermentation was carried out for volatile fatty acids (VFAs) production at different pH (between 7.0 and 10.0) conditions with untreated sludge and heat-alkaline pretreated waste activated sludge. In the fermentation with untreated sludge, the extent of hydrolysis of organic matters and extent of acidification at alkaline pH are 54.37% and 30.37%, respectively, resulting in the highest VFAs yield at 235.46mg COD/gVS of three pH conditions. In the fermentation with heat-alkaline pretreated sludge, the acidification rate and VFAs yield at neutral pH are 30.98% and 240.14mg COD/gVS, respectively, which are higher than that at other pH conditions. With the glucose or bovine serum albumin as substrate for VFAs production, the neutral pH showed a higher VFAs concentration than the alkaline pH condition. The results of terminal restriction fragment length polymorphism (T-RFLP) analysis indicated that the alkaline pH caused low microbial richness. Based on the results in this study, we demonstrated that the alkaline pH is favor of hydrolysis of organic matter in sludge while neutral pH improved the acidogenesis for the VFAs production from sludge. Our finding is obvious different to the previous research and helpful for the understanding of how heat-alkaline pretreatment and alkaline fermentation influence the VFAs production, and beneficial to the development of VFAs production process.

  15. Effect of pH on Penetration of Naphthaleneacetic Acid and Naphthaleneacetamide Through Isolated Pear Leaf Cuticle 1

    PubMed Central

    Norris, Robert F.; Bukovac, Martin J.

    1972-01-01

    Penetration of naphthaleneacetic acid through enzymatically isolated upper pear (Pyrus communis L. cv. Bartlett) leaf cuticle increased as the donor pH was decreased. Naphthaleneacetamide penetration was not influenced by donor pH. The effect of pH on naphthaleneacetic acid penetration was reversible. Higher receiver (simulated leaf interior) pH favored penetration of naphthaleneacetic acid. Changes in the degree of dissociation, and hence polarity, as controlled by hydrogen ion concentration was the prime factor in the response of naphthaleneacetic acid to pH. At pH values lower than the pK (4.2 for naphthaleneacetic acid), the molecule was primarily undissociated, lipophilic, and penetrated into the cuticle; whereas, at pH values above the pK naphthaleneacetic acid was ionized, hydrophilic, and penetrated the cuticle with difficulty or not at all. Data presented are consistent with the hypothesis that naphthaleneacetic acid and naphthaleneacetamide penetration through the cuticle takes place by diffusion. PMID:16658011

  16. Effect of pH and lactic or acetic acid on ethanol productivity by Saccharomyces cerevisiae in corn mash.

    PubMed

    Graves, Tara; Narendranath, Neelakantam V; Dawson, Karl; Power, Ronan

    2006-06-01

    The effects of lactic and acetic acids on ethanol production by Saccharomyces cerevisiae in corn mash, as influenced by pH and dissolved solids concentration, were examined. The lactic and acetic acid concentrations utilized were 0, 0.5, 1.0, 2.0, 3.0 and 4.0% w/v, and 0, 0.1, 0.2, 0.4, 0.8 and 1.6% w/v, respectively. Corn mashes (20, 25 and 30% dry solids) were adjusted to the following pH levels after lactic or acetic acid addition: 4.0, 4.5, 5.0 or 5.5 prior to yeast inoculation. Lactic acid did not completely inhibit ethanol production by the yeast. However, lactic acid at 4% w/v decreased (P<0.05) final ethanol concentration in all mashes at all pH levels. In 30% solids mash set at pH < or =5, lactic acid at 3% w/v reduced (P<0.05) ethanol production. In contrast, inhibition by acetic acid increased as the concentration of solids in the mash increased and the pH of the medium declined. Ethanol production was completely inhibited in all mashes set at pH 4 in the presence of acetic acid at concentrations > or =0.8% w/v. In 30% solids mash set at pH 4, final ethanol levels decreased (P<0.01) with only 0.1% w/v acetic acid. These results suggest that the inhibitory effects of lactic acid and acetic acid on ethanol production in corn mash fermentation when set at a pH of 5.0-5.5 are not as great as that reported thus far using laboratory media.

  17. Isoelectric focusing of dansylated amino acids in immobilized pH gradients

    NASA Technical Reports Server (NTRS)

    Bianchi-Bosisio, Adriana; Righetti, Pier Giorgio; Egen, Ned B.; Bier, Milan

    1986-01-01

    The 21 free amino acids commonly encountered in proteins have been transformed into 'carrier ampholyte' species by reacting their primary amino groups with dansyl chloride. These derivatives can thus be focused in an immobilized pH gradient covering the pH interval 3.1 to 4.1, except for arginine, which still retains a pI of 8.8. Due to their inherent fluorescence, the dansyl derivatives are revealed in UV light, with a sensitivity of the order of 2-4 ng/sq mm. All nearest neighbors are separated except for the following couples: Asn-Gln, Gly-Thr, Val-Ile and Cys-Cys2, with a resolving power, in a Delta(pI) scale, of the order of 0.0018 pH units. Except for a few cases (notably the aromatic amino acids), the order of pI values is well correlated with the pK values of carboxyl groups, suggesting that the latter are not altered by dansylation. From the set of pK(COOH)-pI values of the different amino acids, the pK of the tertiary amino group in the dansyl label has been calculated to be 5.11 + or - 0.06. Knowing the pK of the amino-dansyl and the pI of the excess, free dansyl label (pI = 3.34), a pK of 1.57 is derived for its sulfonic acid group.

  18. Thermodynamic Solubility Profile of Carbamazepine-Cinnamic Acid Cocrystal at Different pH.

    PubMed

    Keramatnia, Fatemeh; Shayanfar, Ali; Jouyban, Abolghasem

    2015-08-01

    Pharmaceutical cocrystal formation is a direct way to dramatically influence physicochemical properties of drug substances, especially their solubility and dissolution rate. Because of their instability in the solution, thermodynamic solubility of cocrystals could not be determined in the common way like other compounds; therefore, the thermodynamic solubility is calculated through concentration of their components in the eutectic point. The objective of this study is to investigate the effect of an ionizable coformer in cocrystal with a nonionizable drug at different pH. Carbamazepine (CBZ), a nonionizable drug with cinnamic acid (CIN), which is an acidic coformer, was selected to prepare CBZ-CIN cocrystal and its thermodynamic solubility was studied in pH range 2-7. Instead of HPLC that is a costly and time-consuming method, a chemometric-based approach, net analyte signal standard addition method, was selected for simultaneous determination of CBZ and CIN in solution. The result showed that, as pH increases, CIN ionization leads to change in CBZ-CIN cocrystal solubility and stability in solution. In addition, the results of this study indicated that there is no significant difference between intrinsic solubility of CBZ and cocrystal despite the higher ideal solubility of cocrystal. This verifies that ideal solubility is not good parameter to predict cocrystal solubility.

  19. Kinetic investigation of recombinant human hyaluronidase PH20 on hyaluronic acid.

    PubMed

    Fang, Shiping; Hays Putnam, Anna-Maria A; LaBarre, Michael J

    2015-07-01

    The kinetic investigation of hyaluronidases using physiologically relevant hyaluronic acid (HA or hyaluronan) substrate will provide useful and important clues to their catalytic behavior and function in vivo. We present here a simple and sensitive method for kinetic measurement of recombinant human hyaluronidase PH20 (rHuPH20) on HA substrates with sizes ranging from 90 to 752 kDa. The method is based on 2-aminobenzamide labeling of hydrolyzed HA products combined with separation by size exclusion-ultra performance liquid chromatography coupled with fluorescence detection. rHuPH20 was found to follow Michaelis-Menten kinetics during the initial reaction time. Optimal reaction rates were observed in the pH range of 4.5-5.5. The HA substrate size did not have significant effects on the initial rate of the reaction. By studying HA substrates of 215, 357, and 752 kDa, the kinetic parameters Km, Vmax, and kcat were determined to be 0.87-0.91 mg/ml, 1.66-1.74 NM s(-1), and 40.5-42.4 s(-1), respectively. This method allows for direct measurement of kinetics using physiologically relevant HA substrates and can be applied to other hyaluronidase kinetic measurements.

  20. Study of metabolic profile of Rhizopus oryzae to enhance fumaric acid production under low pH condition.

    PubMed

    Liu, Ying; Xu, Qing; Lv, Chunwei; Yan, Caixia; Li, Shuang; Jiang, Ling; Huang, He; Ouyang, Pingkai

    2015-12-01

    Ensuring a suitable pH is a major problem in industrial organic acid fermentation. To circumvent this problem, we used a metabolic profiling approach to analyze metabolite changes in Rhizopus oryzae under different pH conditions. A correlation between fumaric acid production and intracellular metabolic characteristics of R. oryzae was revealed by principal component analysis. The results showed that to help cell survival in the presence of low pH, R. oryzae altered amino acid and fatty acid metabolism and promoted sugar or sugar alcohol synthesis, corresponding with a suppressing of energy metabolism, phenylalanine, and tyrosine synthesis and finally resulting in the low performance of fumaric acid production. Based on this observation, 1 % linoleic acid was added to the culture medium in pH 3.0 to decrease the carbon demand for cell survival, and the fumaric acid titer was enhanced by 39.7 % compared with the control (pH 3.0 without linoleic acid addition), reaching 18.3 g/L after 84 h of fermentation. These findings provide new insights into the mechanism by which R. oryzae responds to acidic stress and would be helpful for the development of efficient strategies for fumaric acid production at low pH.