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1.
This paper compares lake chemistry in the Adirondack region of New York measured by the Temporally Integrated Monitoring of Ecosystems (TIME) and Adirondack Long-Term Monitoring (ALTM) programs by examining the data from six lakes common to both programs. Both programs were initiated in the early 1990s to track the efficacy of emission reduction policies and to assess the full impacts of acid deposition on surface water chemistry. They now serve to inform on the emerging chemical recovery of these waters. The Adirondack TIME program utilizes a probability-based approach to assess chronic acidification in a population of lakes using one summer sample per year. The ALTM attempts to track changes in both chronic and episodic acidification across a gradient of lake types using monthly samples. The ALTM project has two important attributes that contrast with the TIME program in the Adirondacks: higher temporal resolution (monthly versus once during the summer or fall) and speciation of aluminum. In particular, the ALTM program provides inorganic monomeric aluminum (AlIM), the fraction of Al that is most toxic. The monthly sampling of the ALTM program includes the spring snowmelt period when acid-neutralizing capacity and pH are near their lowest and Al levels are near their highest. We compare chemistry trends (1992?C2008) for sulfate, nitrate, base cations, dissolved organic carbon, hydrogen ion, acid neutralizing capacity, and Al for the six lakes common to both programs. We also compare relatively high springtime AlIM concentrations from the ALTM with relatively low summertime total Al concentrations from the TIME, showing that the ALTM program provides a more biologically relevant indicator of the effects of acid deposition, illustrating the value of the complementary monitoring efforts in the Adirondack region.  相似文献   

2.
Within the present North American range of Atlantic salmon, severe acid rain effects are limited to the Southern Upland area of Nova Scotia. In the Southern Upland, long range transport of H2SO4 has caused many rivers to decline in pH to the point where their Atlantic salmon stocks have been destroyed or much diminished. Chemical records show a declining pH trend in N.S. rivers since the early 1950s. Eighty % of the annual variation in H+ concentration can be accounted for by a multiple linear regression model on excess sulphate, total Al and organic anions. It is technically feasible to restore the acidified salmon habitat by the addition of limestone; the total cost of mounting a liming program to restore the lost habitat has been estimated at $4.75 × 106 yr?1. The pre-acidification Atlantic salmon production capacity of the Southern Upland was estimated from physical habitat surveys and tag return data to be about 45 000 fish yr?1. Acidification has caused a 50% decline to the current production level of about 23 000 fish yr?1. The costs of the liming program, when compared to the economic benefits of the anticipated salmon enhancement, are economically unjustifiable. The eradication of salmon from such large regions will hinder future programs to reestablish the species in their former range when pollution of the atmosphere is eventually brought under control. Present plans are for a small liming program to establish a series of refuges for the preservation of nuclei of native salmon stocks.  相似文献   

3.
A long-term predictive model, MAGIC, was applied to a Central Amazonian catchment area to illustrate large scale deforestation effects on ‘islands’ of preserved areas, for the situations with and without climate changes. In addition, model sensitivity in response to different organic matter levels in the soil and stream waters as well as to different Al solubility constants was evaluated. The model output was strongly dependent on the chosen values of organic matter concentration and Al solubility constant. Application of the model to a 30 yr deforestation program revealed increases in streamwater ionic concentrations with or without climate change, although streamwater ionic concentrations were predicted to be higher as a consequence of climate change. On the centennial scale, streamwater ionic concentrations reach a new equilibrium, with concentrations higher than those prior to the surrounding deforestation. With the assumed increased cation deposition to the preserved forest areas, soil exchangeable cation concentrations increase with time and aluminum is released to solution. At the end of the simulated deforestation program, SO 4 2? in the preserved areas began to be released to streamwater, inducing acidification. Application of the MAGIC model makes possible to estimate, for the rainforest environment, water quality changes as a function of different climate and land use changes.  相似文献   

4.
The use of emissions trading (cap and trade) is gaining worldwide recognition as an extremely effective policy tool. More than 4 million tons of SO2 have been reduced annually from sources participating in the US SO2 emissions trading program. Ambient SO2 levels and sulfate deposition have decreased by over 25 percent in the most sensitive ecosystems. By harnessing market forces, the program has led to significant cost savings. This paper discusses the results of the US SO2 emissions trading program and emerging efforts in the US and around the world to use emissions trading.  相似文献   

5.
In the 1950s a network of stations for observation of the chemical composition of air and precipitation was established in Europe. Analyzing these data, Oden (1968) was able to show that a central area in Europe with highly acid precipitation was expanding from year to year. This was further substantiated by Granat (1972), and the explanation is the increasing use of fossil fuels in Europe. In 1969, the problem was examined by OECD, and on the initiative of the Scandinavian countries, a joint research program to study the long range transport of air pollutants was started in 1972. The program will be completed with a final report in 1976. In this program, atmospheric dispersion models are used to describe emission, dispersion and deposition of SO2 and sulphate with particular emphasis on the acidification of the precipitation. An emission field has been constructed for Europe, and data from the European weather forecasting system are used for the dispersion calculations. Calculated concentrations and deposition are compared with data from about 70 ground stations and measurements from aircraft. Results show that the main cause for acidification of precipitation is the increasing use of fossil fuels. Large amounts of H2SO4 can be transported over distances up to a few thousand kilometers. In southern Scandinavia where the soil is highly acid (podsol), this has caused severe damage to life in rivers and lakes, and it is feared that in the future, there will be serious damage to forestry. In the Alps, where the soil has a high carbonate content, such effects are not expected. The long range transport of air pollutants has also been shown to increase the corrosion of materials. Work is now in progress to establish a more permanent system for the monitoring of air pollutants in Europe. The first plans for such a system were presented at the meeting in Oslo in December 1974, where countries from both Eastern and Western Europe participated. The work is supported by the Economic Commission for Europe, UN, in cooperation with other international organizations such as the World Meteorological Organization and the GEMS program of the United Nations Environment Programme. In this connection, studies have also been taken up in several countries concerning the effects of the long range transport of air pollutants. In the future monitoring system, a coordination of these efforts is envisaged.  相似文献   

6.
Early-season sprays of calcium chloride (CaCl2) have been reported to sometimes be more effective than later-season sprays for controlling bitter pit in apple (Malus × domestica Borkh.). We conducted a two-year study examining the influence of start-timing of CaCl2 spray programs on fruit Ca concentrations and at-harvest bitter pit incidence in ‘Braeburn’ and ‘Honeycrisp’ apples in Washington State, USA. Six biweekly sprays of CaCl2 were applied starting in mid-May (early-start), mid-June (mid-start, the normal commercial start timing), or mid-July (late-start) 2002 and 2003. Although leaf marginal necrosis occurred in all of the CaCl2-treated plots, no spray damage on fruit was observed. All of the CaCl2 spray treatments consistently reduced bitter pit incidence relative to the unsprayed control treatment and usually but not always increased the Ca concentration of subdermal cortical tissue at harvest. The early and mid-start spray programs produced lower bitter pit incidence than the late-start program in only one of four situations. Fruit Ca concentrations in the control and early-start spray program did not differ. Fruit Ca concentrations in the mid- and late-start spray programs were not different, and often were higher than that of the early-start spray program. Bitter pit incidence for each cultivar was inversely related to fruit Ca concentration. Substituting cortical Ca/potassium (K) or Ca/magnesium (Mg) concentration ratios for Ca concentration failed to substantially improve and usually degraded the correlations with bitter pit incidence. The results confirm that starting CaCl2 spray programs in June sometimes is more effective at controlling bitter pit that delaying the start of the spray program until July. The later season sprays tend to be more effective at increasing fruit Ca concentration. There appears to be no detectable advantage for starting spray programs earlier than June. Applying CaCl2 sprays throughout the growing season, starting sometime in June, appears to be the most economical and effective spray management practice for maximizing fruit Ca and minimizing risk of bitter pit development.  相似文献   

7.
This paper discusses the results of the air quality monitoring activities, especially for three of the Ontario Ministry of the Environment's criteria pollutants (SO2, O3, and total suspended particulates). In the early 1960's Nanticoke Hamlet, located on the northern shore of Lake Erie, was selected for a large industrial development program. The first phase saw the commissioning of a 4000 MW Ontario Hydrothermal generating station, a 100 000 bbl day?1 Texaco refinery and a Stelco steel plant with an initial annual capacity of 1.7 × 106 tonnes. Favorable climatological data was one of the criteria used for selecting this site. Extensive monitoring of ambient air and water quality was carried out prior to the construction phase of the program. Post operation monitoring has also been done on a continuous basis. The data collected to date indicate that the impact of the industrial activity on air quality in the Haldimand-Norfolk region has been very small, with less than 20 exceedances per year of the hourly air quality criterion for SO2 (250 ppb) being observed across the network, and total suspended particulates being similar to other rural locations in Ontario. Only 03 has a substantial number of exceedances of the criterion (80 ppb hourly average) during the summer months, primarily due to long-range transport into the area from across Lake Erie.  相似文献   

8.
There are few readily available standard reference soils for which 0.01 M calcium chloride (CaCl2) soil extraction available metals data are available. This study assessed the ease with which new available metals data could be generated for reference soils. Data on 0.01 M CaCl2 available elements for four reference soils from the Wageningen Evaluating Programs for Analytical Laboratories and three reference soils from the Australasian Soil and Plant Analysis Council proficiency testing program are presented. It is difficult to generate new 0.01 M CaCl2 available metal values for standard reference soils, because trace element concentrations are low and measurements have relatively high variability. We suggest that laboratories can use reference soils as quality control samples in the analysis of 0.01 M CaCl2 available metals by reporting recoveries for major elements (e.g., potassium [K], magnesium [Mg], and sodium [Na], for which reference values are of high reliability) to provide assurance of acceptable extraction efficiency.  相似文献   

9.
Between 1983–94, as acid deposition rates declined, SO4 2? concentrations decreased in 18 of 28 lakes monitored by the upper Midwest LTM program. The expected recovery of ANC and pH was less common, however. Differences in climate may account for divergent trend patterns across the region. Only in Minnesota, where climatic shifts were less pronounced, did we observe a general pattern of increasing lake ANC and pH accompanying declines in SO4 2?. In contrast, the widespread negative trends in lake SO4 2? in the upper Michigan lakes were generally not associated with recovery of ANC and pH, but with decreases in Ca+Mg. These cation decreases may be linked to decreased groundwater inputs during the drier climatic conditions characterizing the study period and decreases in Ca+Mg in atmospheric deposition. In many of the Wisconsin lakes, an overall decline in SO4 2? was precluded by SO4 2? increases during a 4-year drought midway through the study period. During the drought, declining lake water level and volume caused evaporative concentration of solutes, and may have decreased the areal extent of sulfate reduction. Despite controls on sulfur emissions across the region, recovery of pH and ANC has been hindered by climatic shifts and concurrent decreases in atmospheric deposition of cations.  相似文献   

10.
Long range transport of H2SO4 has caused many Nova Scotian rivers to decline in pH to the point where their Atlantic salmon (Salmo salar) stocks have been destroyed or much diminished. Chemical records show a declining pH trend in N.S. rivers since the early 1950's. The annual variation in hydrogen ion activity is positively correlated with sulphate and Al and negatively correlated with organic anions. It is technically feasible to restore the acidified salmon habitat by the addition of limestone, and the total cost of mounting a liming program to restore the lost habitat has been calculated. The pre-acidification Atlantic salmon production capacity was estimated from physical habitat surveys and tag return data. The estimated costs of the liming program are much greater than the anticipated economic benefits of the salmon restoration. Present plans are for a small liming program to establish a series of refuges for the preservation of nuclei of native salmon stocks.  相似文献   

11.
The odor problem around a viscose rayon factory in Arnhem, The Netherlands, was studied quantitatively in a 4 mo program. Methods were developed to relate systematic odor observations in the field to momentary concentrations of two different tracer gases (H2S and CS2). Also a relationship between odor observations and 1 h average CS2-concentrations was assessed. A simple method is described to characterize the long term average odor detectability in the vicinity of the source, and to estimate the impact of an emission reduction on odor detectability.  相似文献   

12.
Previously published results from a multidisciplinary research program, Response of Plants to Interacting Stress (ROPIS), initiated by the Electric Power Research Insitute are summarized here. The overall objective of the ROPIS program was to develop a general mechanistic theory of plant response to air pollutants and other stresses. Direct and indirect phytotoxic impacts of O3 combined with induced deficiencies of key nutrients as a consequence of acidic deposition are important components in many of the hypotheses used to explain reported declines in forest growth. In order to address these concerns as they relate to loblolly pine (Pinus taeda L.) growth and develop a greater level of mechanistic understanding of stress response, a study was formulated with two major objectives: (i) over a multi-yr period evaluate the role of loblolly pine genotype in governing loblolly growth response to O3; and (ii) determine the underlying physiological and edaphic basis for loblolly growth response to O3, acidic precipitation, and soil Mg status. An open-top chamber facility located at Oak Ridge, TN provided controlled O3 exposure for the genotype screening study (1986–88) and controlled O3 exposure and rainfall exclusion and addition for the O3-rainfall acidity-soil Mg interaction study (1987–89). A variety of experimental techniques, measurements, and statistical procedures were used over a 4-yr period to quantify various aspects of plant growth, physiology, and soil-plant relationships. Results from the genotype screening study indicate that although family-specific O3 effects were observed at the end of the first year, no statistically significant O3 effects on diameter, height, or total biomass were evident at the end of three growing seasons; nor were any significant O3-family interactions found. In the interaction study, rainfall acidity and soil Mg level had only minimal affects on seedling growth and physiology. Ozone exposure produced significant changes in many variables, the most important being a net retention of carbon in above-ground biomass and a subsequent reduction in carbon allocation to the root system. This change could have important longterm implications for the tree's ability to obtain water and nutrients, maintain important rhizosphere organisms, and achieve a level of vigor that protects against disease and insect attack.  相似文献   

13.
A titration based model (DeAcid) has been used to predict treatment dose and times for reacidification for CaCO3-treated lakes in the Living Lakes, Inc. (LLI) aquatic liming program. Water quality constitutents (pH, ANC and Ca) were used to measure the effectiveness of the dosing model and reacidification rates. Data from 22 lakes or ponds in 5 northeast states have been collected since June 1986. With few exceptions, pH and ANC values ranged from 4.5 to 6.5 and ?30 to +65 ueq L?1, respectively, in untreated sites and 6.5 to 7.8 and 120 to 300 ueq L?1, respectively, in sites approximately 30 days after treatment. Changes in Ca concentration levels have been used to evaluate the utility of the dose model for treatment of both inland and coastal waters. For coastal, seepage lakes application of a single-box mass transfer model to observed post-liming changes in ANC and Ca adequately simulates lake response.  相似文献   

14.
In 1981, an experimental neutralization program was initiated in Ontario to investigate the feasibility of using neutralization as an interim measure for the protection of acid-sensitive lakes and the restoration of acidified lakes. Aerial applications of powdered limestone (CaC03) to two lakes were used to increase whole-lake pH and alkalinity, and experiments were initiated to investigate the neutralization of lake trout (Salvelinus namaycush) spawning shoals with crushed limestone. Intensive studies are continuing to assess temporal patterns in water chemistry and to evaluate the long-term responses of zooplankton, phytoplankton, zoobenthos and fish communities.  相似文献   

15.
Since January 1972, chemical analysis of daily precipitation samples from about 20 background stations in Norway has been carried out on a routine basis. Air monitoring is carried out at six stations. The chemical analysis program is: sulphate, pH and acidity in precipitation, sulphates and SO2 in air. In addition, more detailed chemical analysis of aerosol and precipitation has been carried out at selected stations. Some results for the measurement period 1972 to 1974 are presented. Comparison of air and precipitation concentrations of S compounds show that the precipitation scavenging efficiency is very high under the conditions in southern Norway.  相似文献   

16.
A monitoring program of particulate matter was conducted at eight sampling sites in four highly industrialized cities (Shenyang, Anshan, Fushun, and Jinzhou) of Liaoning Province in Northeast China to identify the major potential sources of ambient PM2.5. A total of 814 PM2.5 and PM2.5–10 samples were collected between 2004 and 2005. All PM samples were collected simultaneously in four cities and analyzed gravimetrically for mass concentrations. A sum of 16 elemental species concentrations in the PM samples were determined using inductively coupled plasma atomic emission spectroscopy. Annual means of PM2.5 concentrations ranged from 65.0 to 222.0 μg m?3 in all the eight sampling sites, and the spatial and seasonal variations were discussed. Enrichment factors were calculated, and Cr, Cu, Zn, As, Cd, and Pb will be pollution-derived elements. Site-to-site comparisons of PM2.5 species in each city were examined using coefficient of divergence, revealing that the two sites in each city are similar in elemental species. Principle component analysis was used for preliminary source analysis of PM2.5. Three or four factors in each city were isolated, and similar sources (crustal source, coal combustion, vehicle exhaust, iron making, or some other metallurgical activities) were identified at four cities.  相似文献   

17.
Rain event samples have been collected in Haifa, Israel, for nine hydrological years 1981 to 1990. Precipitation amount, pH, SO4 =, NO3 ?, Cl?, NH4 +, Na+, K+, Ca++, Mg++ and alkalinity of rainwater samples were recorded. The sampling and analysis program was based on WMO recommendations for background networks. The sampling was performed manually, and the analysis was based on wet chemistry for ions and atomic absorptions for metals. Data of 187 rain samples showed that the average pH was 5.3±1.1∶ 26% of the rain events were below pH of 5.6 and 23% above pH of 7.0. Some simple chemical mass-balance considerations indicate that natural sources, sea salt and soil carbonates are the main contributors to rain chemistry. However, the presence of low pH events observed over the years suggests that the impact of anthropogenic emissions may overwhelm the buffering capacity of the alkaline aerosol.  相似文献   

18.
Kang  Jin-Kyoo  Song  Yungoo  Moon  Ji-Won  Moon  Hi-Soo 《Water, air, and soil pollution》2001,129(1-4):349-367
The water quality of a stream affected by miningactivities was investigated on the basis of a mineralogical studyfor the related solids, and their subsequent changes weremonitored for a year, so as to clarify the impact of the acidmine drainage (AMD) to the stream. The mine-affected stream wasclassified into Ca–Mg and sulfate type, and the concentrations ofits major constituents ranged from tens to hundreds times higherthan those of the background stream. This was most likely due toacid-generating reactions involving the oxidation of sulfides inthe mineralized zone, and subsequent neutralizations involvingcalcite and chlorite as possible sources of Ca and Mg,respectively. This interpretation is consistent with thethermodynamic and mass-balance calculations. The concentrationsof the dissolved constituents changed seasonally, dependinglargely on rainfall in the mine-affected stream. However, thedramatic decrease in the ratio of Mg/Ca, independent of rainfall,indicates that some changes did occur in sources, including theheterogeneous distribution of main source materials, the changein chemical conditions, especially in pH, pe(Eh), and PCO 2,in the reacting fluid, and the consequential solubility changesin sources. In spite of the limitations of short-term monitoring,it does provide some meaningful information in order to constructa long-term monitoring program.  相似文献   

19.
There is considerable interest in the recovery of surface waters from acidification by acidic deposition. The Adirondack Long-Term Monitoring (ALTM) program was established in 1982 to evaluate changes in the chemistry of 17 Adirondack lakes. The ALTM lakes exhibited relatively uniform concentrations of SO4 2?. Lake-to-lake variability in acid neutralizing capacity (ANC) was largely due to differences in the supply of basic cations (Ca2+, Mg2+, K+, Na+; CB) to drainage waters. Lakes in the western and southern Adirondacks showed elevated concentrations of NO3 ?, while lakes in the central and eastern Adirondacks had lower NO3 ? concentrations during both peak and base flow periods. The ALTM lakes exhibited seasonal variations in ANC. Lake ANC was maximum during the late summer or autumn, and lowest during spring snowmelt. In general Adirondack lakes with ANC near 100 Μeq L?1 during base flow periods may experience decreases in ANC to near or below 0 Μeq L?1 during high flow periods. The ALTM lakes have exhibited long-term temporal trends in water chemistry. Most lakes have demonstrated declining SO4 2?, consistent with decreases in SO2 emissions and SO4 2? in precipitation in the eastern U.S. Reductions in SO4 2? have not coincided with a recovery in ANC. Rather, ANC values have declined in some ALTM lakes. This pattern is most likely due to increasing concentrations of NO3 ? that occurred in most of the ALTM drainage lakes.  相似文献   

20.
张培栋  王刚 《农业工程学报》2005,21(12):147-151
农村户用沼气工程是中国可再生能源建设的重点项目,可为农村居民生活提供清洁的可再生能源,该工程的建设能减轻农村环境污染,有助于部分缓解全球气候变暖的趋势。该文根据国际通用的减排量计算方法,对中国农村户用沼气替代传统生物质能和煤炭所产生的CO2和SO2的减排量进行了计算分析,为制定农村能源发展战略和农村环境发展规划提供参考。研究结果表明,在1996~2003年间,每年可减少CO2排放39.76~419.39万t,减少SO2排放2.13~6.20万t。通过对2010、2020和2050年沼气替代农村传统能源减排CO2和SO2量的预测,证明农村户用沼气工程的建设可以有效减少CO2和SO2的排放。  相似文献   

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