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Tradable Permit Systems: Considering Uncertainty in Emission Estimates
2007
Bartoszczuk, Paweł | Horabik, Joanna
We simulate the market for emission permits by considering uncertainty in emission inventory reports. The approach taken in this analysis is to enhance the emissions reported in each region by a certain part of their uncertainty when compliance with the Kyoto targets is being proved. While this formulation is not new in the literature, we define the uncertainty component in a way that enables comparison with the approach of effective permits presented in Nahorski, Horabik, and Jonas (2007) Compliance and emissions trading under the Kyoto protocol: Rules for uncertain inventories, (this issue). We show and explain that the transformation to effective permits bears additional costs apart from those resulting from shifting the Kyoto targets.
显示更多 [+] 显示较少 [-]Invasives, Introductions and Acidification: The Dynamics of a Stressed River Fish Community
2007
Larsen, Bjørn Mejdell | Sandlund, O. T (Odd Terje) | Berger, Hans Mack | Hesthagen, Trygve
We describe the development of the fish community in the acidified and limed river Litleåna in southern Norway, and describe how chemical restoration, compensatory introductions of exotics, and accidental invasion of exotics interact to influence the population of the naturally occurring brown trout (Salmo trutta). The river Litleåna is a tributary to the river Kvina in Vest-Agder County, southern Norway. During the years 1996-2004, annual mean pH was 4.9-5.0 and 6.1-6.4 above and below the liming facility, which was installed in 1994. Originally, brown trout was the only fish species in the river, but brook trout (Salvelinus fontinalis) have been intentionally introduced, whereas European minnow (Phoxinus phoxinus) was introduced by accident. Fish densities were recorded by means of electrofishing annually over the ten year period 1995-2004. Although close to extinction before liming was initiated, brown trout fry densities increased from 1995 to 1999, with subsequent varying densities. There has been a simultaneous major increase in the occurrence and density of European minnow since 1997. Our results show that both brown trout and European minnow increase after liming. Minnow densities are negatively affected by low pH episodes in the river. The growth rates of brown trout fry are negatively correlated to minnow densities, indicating competition between the species. Brook trout densities have decreased since liming started, and during the brown trout recovery.
显示更多 [+] 显示较少 [-]Atmospheric Metal Pollutants-Archives, Methods, and History
2007
Norton, Stephen A
Pollution of the atmosphere with cadmium (Cd), mercury (Hg), and lead (Pb) is a consequence of human activities. Natural archives are necessary to reconstruct the long-term history of metal deposition because accurate measurement of atmospheric deposition is a recent accomplishment. Reconstructions require: (1) accurate determination of concentrations of elements and isotopes, (2) accurate chronology of archives, and (3) archives that faithfully record atmosphere deposition. The most useful long-term archives are accumulations of ice and snow, peat, and lake sediment. Quantification of Cd deposition is uncommon because of its low concentration and substantial chemical mobility. Nonetheless, trends in peat and lake sediment are similar to those of Hg and Pb since ca. 1800 a.d. Both Hg and Pb are relatively chemically immobile and thus the peat and lake archives are believed to record historic trends of atmospheric deposition. Isotopic and concentration studies of Pb indicate a history of northern hemisphere atmospheric pollution extending back prior to 0 a.d. Although measurements of Hg concentration are now routine, isotopic measurements are in their infancy. Some Hg pollution sources have unique isotopic ratios, thereby contributing unique signals to the total Hg. Maximum accumulation rates of Hg and Pb occur up to 10 years later than for Cd (1970s versus 1960s in eastern North America, perhaps slightly later in Europe). By 2004, deposition of Cd, Hg, and Pb had declined from peak values in eastern North America more than 75, 75, and 90%, respectively.
显示更多 [+] 显示较少 [-]Accumulation of metals in macrophytes from water reservoirs of a power supply plant, Rio de Janeiro State, Brazil
2007
Valitutto, R.S. | Sella, S.M. | Silva-Filho, E.V. | Pereira, R.G. | Miekeley, N.
Aquatic macrophytes are well known accumulators for heavy metals, the reason why they are used as bioindicators for water quality and in phytoremediaton strategies. This study reports on the elemental concentrations in four free-floating aquatic macrophytes (S. auriculata; P. stratiotes; E. crassipes and E. azurea) growing in two water reservoirs (Santana e Vigário, Rio de Janeiro State, Brazil) of an electric power plant that receive input from the polluted Paraíba do Sul River. Filtered water samples and water suspended solids from these environments were also analysed. Inductively coupled plasma mass spectrometry was used as the principal method, allowing the determination of up to 41 elements, including the rare-earth elements (REEs) and other trace metals not assayed before in these macrophytes. The results show that all elements studied are accumulated by the macrophytes with concentration ratios (CR = [plant]: [water]) varying from about 1,000 to 200,000, based on the dry weight of the plant species. With a few exceptions, highest accumulations were observed in E. crassipes in which CRs increase in the sequence: Cu < Mo < Cr < Pb < Tl < Fe < La < Zn < Ce< Mn. Surprisingly high CRs (e.g. Ce: 74,000) and corresponding mass concentrations were observed for the rare-earth elements (e.g. [summation operator]REE: 112 mg kg-¹), also measured in the water suspended particle fraction. The results show that this fraction acts as an effective sink for trace metals in the aquatic system studied and seems to play also an important role in the transfer of metals from water to the plant species.
显示更多 [+] 显示较少 [-]A Combination of Bulk and Single Particle Analyses for Asian Dust
2007
Ma, Chang-Jin | Choi, Kum-Chan
A multi-stage particle sampling instrument and a particle counter were operated at the ground monitoring site in Fukuoka where was directly exposed to the outflow of air masses from the Asian continent during the springtime of 2005. The bulk and individual dust particles were analyzed simultaneously by ICP-MS and micro-PIXE, respectively. The ground-based observation of dust storm by the Japan Meteorological Agency and by the NOAA HYSPLIT dispersion-trajectory model indicated that dust storm was driven from the Chinese continent including dust source area. The number concentration of gigantic particles (e.g., larger than 5 μm) was measured to be 10 times higher in an Asian dust storm (hereafter called “ADS”) period than in a non-ADS period. There is an outstanding increase of mass concentration in the range of 3.5-7.7 μm in ADS event. In ADS event, soil fraction accounts 57.9-70.1% of particle mass concentration in coarse particles larger than 3.5 μm. Micro-PIXE analysis enables us to classify individual dust particles into several types. The particles with 3.5-5.1, 5.1-7.7, and 7.7-10.9 μm experienced aging processes by 60.6, 69.2, and 77.2%, respectively. On the basis of the reconstructed elemental maps by micro-PIXE analysis, the chemical transformation of dust particles was also presumed.
显示更多 [+] 显示较少 [-]Accumulation of Metals in the Sediment and Reed Biomass of a Combined Constructed Wetland Treating Domestic Wastewater
2007
Lesage, E. | Rousseau, D. P. L. | Meers, E. | Van de Moortel, A. M. K. | Du Laing, G. | Tack, F. M. G. | De Pauw, N. | Verloo, M. G.
This study assessed the accumulation of Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn in the sediment and biomass of P. australis (Cav.) Trin. ex Steud. in a combined constructed wetland (CW) designed for the treatment of domestic wastewater of 750 population equivalents. The CW consists of two vertical subsurface flow (VSSF) reed beds followed by two horizontal subsurface flow (HSSF) reed beds. The sediment in the VSSF reed bed was contaminated with Cu (201 ± 27 mg kg-¹ DM) and Zn (662 ± 94 mg kg-¹ DM) after 4 years of operation. Concentrations of Cd, Cu, Pb and Zn in the sediment generally decreased along the treatment path of the CW. On the contrary, higher Al, Cr, Fe, Mn and Ni concentrations were observed in the sediment of the inlet area of the HSSF reed bed. Redox conditions were presumably responsible for this observed trend. Metal concentrations in the reed biomass did not show excessive values. Accumulation in the aboveground reed biomass accounted for only 0.5 and 1.4% of, respectively, the Cu and Zn mass load in the influent. The sediment was the main pool for metal accumulation in the CW.
显示更多 [+] 显示较少 [-]The Applicability of National Critical Loads Data in Assessing Designated Sites
2007
Hall, Jane | Ullyett, Jackie | Wadsworth, Richard | Reynolds, Brian
Critical loads have been successfully used within Europe in the development of effects-based policies for pollution abatement, including the Second Sulphur Protocol and the Protocol to abate acidification, eutrophication and ground-level ozone (CLRTAP, 1979). This success has encouraged the UK Environment Agency and Conservation Agencies to use the national critical load maps as a screening tool in assessing the threats from acidification and eutrophication to designated (Natura 2000) sites. The UK maps of critical loads are based on national-scale data sets appropriate for national-scale assessments, and were never intended for use at the site-specific level. Site-based assessments are often targeted at Special Areas of Conservation, a sub-set of the UK Natura 2000 sites. The spatial data available includes the boundaries of the sites but not the location of the designated features. Ancillary data is variable from one site to another; habitat types may be described in detail with cross-reference to classes of the National Vegetation Classification (NVC: Rodwell, 1991 et seq), but information available on soils and geology is generalised and has not been related to the habitats or species being protected. Hence it can be difficult to relate the individual sites to the national maps, even where appropriate to do so. This paper examines the underlying uncertainties in the national critical load maps showing how the maps could give misleading results if used for site-specific assessments. It also includes advice on how to determine when the national data may be appropriate as a policy-tool at the site-level.
显示更多 [+] 显示较少 [-]Acid Rain in Downtown São Paulo City, Brazil
2007
dos Santos, Marcos A | Illanes, Cynthia F | Fornaro, Adalgiza | Pedrotti, Jairo J
During the period from July 2002 to June 2004, the chemical characteristics of the rainwater samples collected in downtown São Paulo were investigated. The analysis of 224 wet-only precipitation samples included pH and electrical conductivity, as well as major ions (Na⁺, [graphic removed] , K⁺, Ca²⁺, Mg²⁺, Cl-, [graphic removed] , [graphic removed] ) and carboxylic acids (acetic, formic and oxalic) using ion chromatography. The volume weighted mean, VWM, of the anions [graphic removed] , [graphic removed] and Cl- was, respectively, 20.3, 12.1 and 10.7 μmol l-¹. Rainwater in São Paulo was acidic, with 55% of the samples exhibiting a pH below 5.6. The VWM of the free H⁺ was 6.27 μmol l-¹), corresponding to a pH of 5.20. Ammonia (NH₃), determined as [graphic removed] (VWM = 32.8 μmol l-¹), was the main acidity neutralizing agent. Considering that the H⁺ ion is the only counter ion produced from the non-sea-salt fraction of the dissociated anions, the contribution of each anion to the free acidity potential has the following profile: [graphic removed] (31.1%), [graphic removed] (26.0%), CH₃COO- (22.0%), Cl- (13.7%), HCOO- (5.4%) and [graphic removed] (1.8%). The precipitation chemistry showed seasonal differences, with higher concentrations of ammonium and calcium during autumn and winter (dry period). The marine contribution was not significant, while the direct vehicular emission showed to be relevant in the ionic composition of precipitation.
显示更多 [+] 显示较少 [-]Atmospheric Deposition of Reactive Nitrogen on Turf Grassland in Central Japan: Comparison of the Contribution of Wet and Dry Deposition
2007
Hayashi, Kentaro | Komada, Michio | Miyata, Akira
The atmospheric deposition of reactive nitrogen on turf grassland in Tsukuba, central Japan, was investigated from July 2003 to December 2004. The target components were ammonium, nitrate, and nitrite ions for wet deposition and gaseous ammonia, nitric and nitrous acids, and particulate ammonium, nitrate, and nitrite for dry deposition. Organic nitrogen was also evaluated by subtracting the amount of inorganic nitrogen from total nitrogen. A wet-only sampler and filter holders were used to collect precipitation and the atmospheric components, respectively. An inferential method was applied to calculate the dry deposition velocity of gases and particles, which involved the effects of surface wetness and ammonia volatilization through stomata on the dry deposition velocity. The mean fraction of the monthly wet to total deposition was different among chemical species; 37, 77, and 1% for ammoniacal, nitrate-, and nitrite-nitrogen, respectively. The annual deposition of inorganic nitrogen in 2004 was 47 and 48 mmol m-² yr-¹ for wet and dry deposition, respectively; 51% of atmospheric deposition was contributed by dry deposition. The annual wet deposition in 2004 was 20, 27, and 0.07 mmol m-² yr-¹, and the annual dry deposition in 2004 was 35, 7.4, and 5.4 mmol m-² yr-¹ for ammoniacal, nitrate-, and nitrite-nitrogen, respectively. Ammoniacal nitrogen was the most important reactive nitrogen because of its remarkable contribution to both wet and dry deposition. The median ratio of the organic nitrogen concentration to total nitrogen was 9.8, 17, and 15% for precipitation, gases, and particles, respectively.
显示更多 [+] 显示较少 [-]UN/ECE ICP Materials Dose-response Functions for the Multi-pollutant Situation
2007
Kucera, Vladimir | Tidblad, Johan | Kreislova, Katerina | Knotkova, Dagmar | Faller, Markus | Reiss, Daniel | Snethlage, Rolf | Yates, Tim | Henriksen, Jan | Schreiner, Manfred | Melcher, Michael | Ferm, Martin | Lefèvre, Roger-Alexandre | Kobus, Joanna
A “multi-pollutant exposure programme” reflecting the new pollution situation where SO₂ is no longer the dominating pollutant has been performed by the International Co-operative Programme on Effects on Materials, including Historic and Cultural Monuments (ICP Materials) within the activities of the Convention on Long-range Transboundary Air Pollution. The main results obtained in the period 1997-2003 are summarised. Dose-response functions are presented for carbon steel, zinc, copper, bronze and limestone. Parameters involved in the functions include besides SO₂ and pH, which were included in the previously developed functions from ICP Materials, also the effect of particulate matter and HNO₃.
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