Two Elsholtzia haichowensis S. populations, copper-tolerant (TLS) and non-tolerant (HA) ones were studied in hydroponic experiment for the nitrogen assimilation and plant growth under excess Cu conditions. The results demonstrated that there were surely the differences in nitrogen assimilation and plant growth between the two populations. Excess Cu caused evident decreases in the shoot and root biomass and root/shoot biomass ratio in HA population while no significant changes happened in TLS population. In addition, in HA population, excess Cu also induced apparent declines in activities of nitrate reductase (NR, EC 1.6.6.1) and glutamine synthetase (GS, EC 6.3.1.2) in the leaves and roots as well as the contents of nitrate, ammonium and amino acids in the roots. In TLS population, excess Cu did not significantly affect the NR activities in the leaves and roots and the nitrate content in the roots, and apparently elevated the root ammonium and amino acids contents, although it also clearly reduced the GS activities in the leaves and roots. Besides, with the addition of Cu in the culture solution, the Cu contents in the leaves and roots of the two populations markedly increased. But this increase was significantly lower in TLS population than that in HA population; the fact might be partly responsible for the relative stabilization of nitrogen assimilation in TLS population compared to that in HA population.

To rigorously assess treatment technologies and establish regulatory framework for chromate-contaminated site remediation, it is useful to know the exact chromium speciation in soil matrices. In an earlier study, Thornton, E. C., & Amonette, J. E. (1999). Hydrogen sulfide gas treatment of Cr(VI)-contaminated sediment samples from a plating-waste disposal site - implications for in-situ remediation. Environmental Science & Technology, 33, 4096-4101, reported that some chromate in the bulk particles was not accessible to gaseous reductants or solution-phase extractants, based on XANES studies. We hypothesized that part of this non-extractable chromate may reside in the structure of minerals such as calcium carbonate. To test this hypothesis, a number of calcium carbonate precipitates were prepared in the presence of various concentrations of chromate during the precipitation, which could coprecipitate chromate, or by adding chromate after the precipitation was completed. Hydrochloric acid was used to dissolve calcium carbonate and therefore extract the coprecipitated and surface attached chromate. The results showed that the coprecipitated chromate was non-extractable by hot alkaline solution or phosphate buffer, but could be solubilized by HCl in proportional to the amount of calcium carbonate dissolved. The X-ray diffraction experiments revealed that the coprecipitation of chromate with calcium carbonate had an influence on its crystal structure: The higher the chromate concentration, the greater the ratio of vaterite to calcite.

On the coastal plains of Finland there are approximately 3,000 km² of acid sulfate soils developed as a result of intensive agricultural drainage of waterlogged sulfide-bearing sediments. The runoff from these soils contains very high amounts of acidity and metals that have severely deteriorated the aquaculture in several downstream rivers and estuaries. Therefore, there is an urgent need to develop and test more environmental friendly ways of draining landscapes underlain with these nasty soils. In this study, over a 3-year monitoring period the effect of excess surface liming, controlled drainage and lime filter drainage of acid sulfate soils on runoff water quality (pH, sulfate, metals) was determined and assessed. The results showed that (1) the liming measures had not prevented severely acidic and metal-rich waters from forming and discharging from the soils, (2) the controlled drainage system might have reduced discharge peaks but its potential effects on the discharged water quality were nondetectable due to its small effect on the groundwater level and naturally inherited heterogeneities, and (3) the spatial and temporal variations identified for the various hydrochemical determinants were not caused by the kind of treatment applied. Therefore, on acid sulfate soil fields, like the one studied here, the short-term hydrochemical effects of the treatments tested are minor (or nonexistent) at least as long as the controlled drainage systems are not technically improved or better maintained.

Industrial soils near Zn-Pb mines and metallurgical plants in the vicinity of Olkusz (southern Poland) are exposed to high environmental stress related to heavy metal pollution (Zn, Pb, Cd, Mn, Fe, Tl and As) from waste disposal sites and primary ores. X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive spectrometry analyses (EDS) and Atomic Absorption Spectroscopy (AAS) were used to analyse rhizosphere soil samples from the area. The mineral composition of the rhizosphere soils was determined. Carbonates of lead, cadmium and zinc, arsenic-lead sulphosalts and other minerals occurring on the root epiderm are described. Mineral aggregates of secondary origin include polymineralic spherules containing high concentrations of Zn (up to 2.3%), Pb (up to 0.7%), Fe (up to 23%), Cd (up to 427 mg kg-¹) and Tl (up to 139 mg kg-¹). Processes on the rhizoplane, and in the zone where plant-root exudation solutions are active, promote the crystallization of metalliferous minerals. ESEM is recommended as an efficient method for examining alteration occurring in the rhizosphere environment.

The objective of this study was to identify and quantify volatile organic compounds (VOCs) produced during composting of poultry litter. The VOCs produced from in-vessel composting with a controlled aeration system were tested using the F-ITR method by VOC analyzer. Alkanes and alkylated benzenes were emitted in the highest amounts from poultry litter, while aldehydes, terpenes, ketones were emitted in much lesser amounts. Studies showed that VOCs generation was the greatest early during the composting process and greatly reduced thereafter. Composting temperatures were found to affect VOCs. All VOCs were least with the high temperatures generated during composting.

The aim of the present study was the influence of various methods of long-term soil utilisation on the content of polycyclic aromatic hydrocarbons (PAH) in selected silty soils. Four soils were selected for the present studies, i.e.: Eutric Fluvisol originating from silty formations, Haplic Phaeozem developed from loess, Haplic Luvisol (non-uniform) developed from silt, Haplic Luvisol developed from loess. Five study sites were chosen, i.e.: apple orchards, hop gardens, fields, grasslands and natural woodland ecosystems. Samples were collected from the depth of 0-10 cm. In the samples the content of 16 PAHs was determined by means of the HPLC-UV method. The total PAHs content was at a low level. Depending on the soil and object type, the total PAHs content ranged from 72.5 to 764.0 μg·kg-¹. The pollutant level determined together with composition of individual PAHs suggested a limited anthropogenic influence relating mainly to pyrolytic processes. The total PAH content as well as the content of individual PAHs depended on agricultural land use and management. It has been shown that PAH level was influenced by environmental conditions specific for a given type of land use. In the soils in which organic carbon content differed only slightly among locations, a higher influence of the soil utilisation method on the content of individual PAHs was observed.

Leaching experiments of rebuilt soil columns with two simulated acid rain solutions (pH 4.6-3.8) were conducted for two natural soils and two artificial contaminated soils from Hunan, south-central China, to study effects of acid rain on competitive releases of soil Cd, Cu, and Zn. Distilled water was used in comparison. The results showed that the total releases were Zn>Cu>Cd for the natural soils and Cd>Zn[double greater-than sign]Cu for the contaminated soils, which reflected sensitivity of these metals to acid rain. Leached with different acid rain, about 26-76% of external Cd and 11-68% external Zn were released, but more than 99% of external Cu was adsorbed by the soils, and therefore Cu had a different sorption and desorption pattern from Cd and Zn. Metal releases were obviously correlated with releases of TOC in the leachates, which could be described as an exponential equation. Compared with the natural soils, acid rain not only led to changes in total metal contents, but also in metal fraction distributions in the contaminated soils. More acidified soils had a lower sorption capacity to metals, mostly related to soil properties such as pH, organic matter, soil particles, adsorbed SO₄ ²-, exchangeable Al³⁺ and H⁺, and contents of Fe₂O₃ and Al₂O₃.

Emissions trading in the European Union (EU), covering the least uncertain emission sources of greenhouse gas emission inventories (CO₂ from combustion and selected industrial processes in large installations), began in 2005. During the first commitment period of the Kyoto Protocol (2008-2012), the emissions trading between Parties to the Protocol will cover all greenhouse gases (CO₂, CH₄, N₂O, HFCs, PFCs, and SF₆) and sectors (energy, industry, agriculture, waste, and selected land-use activities) included in the Protocol. In this paper, we estimate the uncertainties in different emissions trading schemes based on uncertainties in corresponding inventories. According to the results, uncertainty in emissions from the EU15 and the EU25 included in the first phase of the EU emissions trading scheme (2005-2007) is ±3% (at 95% confidence interval relative to the mean value). If the trading were extended to CH₄ and N₂O, in addition to CO₂, but no new emissions sectors were included, the tradable amount of emissions would increase by only 2% and the uncertainty in the emissions would range from -4 to +8%. Finally, uncertainty in emissions included in emissions trading under the Kyoto Protocol was estimated to vary from -6 to +21%. Inclusion of removals from forest-related activities under the Kyoto Protocol did not notably affect uncertainty, as the volume of these removals is estimated to be small.

The characteristics of transport and transformation of SO₂, NOx and O₃ in northeast Asia have been investigated by using a comprehensive regional air quality model (RAQM) driven by a meteorological model MM5. A study period of 1-15 March 2002 has been selected due to the availability of intense observation of chemical species for both ground and upper levels. Model results have been compared against observational data to provide insights into the strength and weakness of the model's ability and the evolutionary features of chemical species. Validation shows a good skill of this model system in reproducing most of the key features in long-range transport, but apparent bias still remains due to a series of uncertainties from either emission estimates, prescribed parameters, or inherent model limitations. In general, this model shows a better skill for SO₂ and O₃ than for NOx. Large discrepancy occurs between the observed and calculated NOx concentration at higher levels, with the model results being much lower. A series of sensitivity tests have been conducted to investigate the potential affecting factors and it is found that the inaccuracy or incompleteness in currently used emission inventories could be a most likely cause for such discrepancy. Long-range transport from Asian continent to the western Pacific is pronounced in springtime. Substantially high concentrations of SO₂ and NOx in or above the boundary layer (0.5~3.0 km) over the Yellow Sea suggest an important pathway for long-range transport in northeast Asia.

Using within-weather-group air pollution prediction models developed in Part I of this research, this study estimates future air pollution levels for a variety of pollutants (specifically, carbon monoxide – CO, nitrogen dioxide – NO₂, ozone – O₃, sulphur dioxide – SO₂, and suspended particles – SP) under future climate scenarios for four cities in south-central Canada. A statistical downscaling method was used to downscale five general circulation model (GCM) scenarios to selected weather stations. Downscaled GCM scenarios were used to compare respective characteristics of the weather groups developed in Part I; discriminant function analysis was used to allocate future days from two windows of time (2040–2059 and 2070–2089) into one of four weather groups. In Part I, the four weather groups were characterised as hot, cold, air pollution-related, and other (defined as relatively good air quality and comfortable weather conditions). In estimating future daily air pollution concentrations, three future pollutant emission scenarios were considered: Scenario I – emissions decreasing 20% by 2050, Scenario II – future emissions remaining at the same level as at the end of the twentieth century, and Scenario III – emissions increasing 20% by 2050. The results showed that, due to increased temperatures, the average annual number of days with high O₃ levels in the four selected cities could increase by more than 40–100% by the 2050s and 70–200% by the 2080s (from the current areal average of 8 days) under the three pollutant emission scenarios. The corresponding number of low O₃ days could decrease by 4–10% and 5–15% (from the current areal average of 312 days). For the rest of the pollutants, future air pollution levels will depend on future pollutant emission levels. Under emission Scenarios II and III, the average annual number of high pollution days could increase 20–40% and 80–180%, respectively, by the middle and late part of this century. In contrast, under Scenario I, the average annual number of high pollution days could decrease by 10–65%.