The sources of copper topsoil variability in agricultural have been evaluated in the northeastern region of the Iberian Peninsula (Spain) using 624 soil samples collected in a standard 8 x 8 km grid. Analyses of variance combined with geostatistical methods have been used to map the spatial variability and to evaluate the relative contribution of natural and anthropic copper sources in topsoils. The use of the residual values derived from the interpolation method have led to the identification of local anomalies in the copper content in relation to agricultural practices carried out on the land. Copper concentrations were relatively low (17.33 ± 14.97 mg/kg) in areas with a high pH level (>8.2) and low organic matter (<1%). In general, the spatial distribution of copper showed a good relationship with the surface evidence of the lithologic units at a regional scale. At a smaller scale, concentration values also indicated the anthropogenic influence related to specific agricultural practices in relation to land use and cultivation methods. The highest mean concentrations were found in vineyards and olive fields. These were partly due to inputs from inorganic fertilisers, mainly copper sulphate, and also to the application of liquid and soil manure.

This paper reports the effect of using coarse substrates in the upper layer of a gravel-based tidal flow reed bed treating pig farm wastewater. The aim of this unconventional medium arrangement is to seek a solution for the problem of clogging that frequently takes place during the treatment of strong wastewaters. Results from lab-scale experiments demonstrated that, in general, employing coarse substrates in the upper layer of the reed bed gave greater efficiency for the removal of organic matter and suspended solids, due to reduced clogging. A specific clogging tendency rate was defined to quantitatively describe the clogging behaviour. Calculation of the tendency rate revealed that the unconventional medium arrangement had a clear advantage over the conventional arrangement of employing fine gravel or sand in top layer.

The main objective of this paper is to check the fulfilment of the European Directive 2004/107/CE, which refers to the limit values of arsenic, cadmium and nickel that will have to be carried out the first of January 2010. Three sampling points have been chosen (Alcora, Vila-real and Castellón), forming a triangle that comprise most of the ceramic cluster of the province of Castellón (Spain). This is a problematic area in relation to the fulfilment of the directive, due to its high industrial development. Apart from this main objective, the following are raised: a) The analysis of the temporal evolution of the levels of As, Cd, Ni and PM10 in the atmosphere during the year 2002; b) The identification of similar behaviour patterns and of the possible common origins in the studied pollutants; c) To show the existence of differences in the behaviour and evolution of As, Cd, Ni and PM10 in the atmospheric medium depending on the location of the sampling point; d) To check whether the levels of As, Cd, Ni and PM10 are influenced by the environmental temperature. The concentration levels of arsenic, cadmium and nickel in Alcora, Vila-real and Castellón have been determined during the year 2002, in order to check whether they are below the limits established in the future directive on these elements. The following conclusions are reached from the results obtained after the chemical analysis (using ICP–MS) of the samples collected in the three locations.

Aluminum in acidic conditions is toxic to plants. Aluminum tolerance in some plant species has been ascribed to arbuscular mycorrhizal fungal symbiosis. In this study, the application of aluminum was found to inhibit mycelia development of saprobe fungi Fusarium concolor and Trichoderma koningii and the hyphal length of the arbuscular mycorrhizal fungi Glomus mosseae and Glomus deserticola in vitro. Several levels of aluminum were applied to Eucalyptus globulus plants and inoculated with arbuscular mycorrhizal fungi alone or together with both saprobe fungi. The application of 1,500 mg kg⁻¹ decreased the shoot and root dry weight, chlorophyll content and total P, Mg, and Ca concentrations in the shoot of E. globulus. However, both mycorrhizal fungi G. mosseae and G. deserticola inoculated alone increased the shoot dry weight of Eucalyptus, compared with a non- arbuscular mycorrhizal inoculated control treated with 1,500 mg kg⁻¹ of aluminum. When 1,500 mg kg⁻¹ of aluminum was applied, T. koningii increased the effect of G. deserticola on the shoot weight of eucalyptus, whereas with 3,000 mg kg⁻¹, shoot weight and arbuscular mycorrhizal colonization decreased in all treatments. With 1,500 mg kg⁻¹, the highest accumulation of aluminum in the shoot was obtained when G. deserticola was inoculated together with T. koningii. The possibility of manipulating an arbuscular mycorrhizal inoculation together with a saprobe fungus confers a high aluminum resistance in E. globulus. The effect of such combined inoculation is particularly important in some Chilean volcanic acid soils, mainly those which have been intensively cropped and are without lime addition, which facilitates the increase of phytotoxic aluminum species and limits their agricultural use. Therefore, such dual inoculation in field conditions deserves further investigation. Overall, the arbuscular mycorrhizal and saprobe fungi contribute to the increase in resistance of E. globulus to aluminium.

A study was conducted to determine the efficiency and effectiveness of two commercial microbial based bioremediation products compared to indigenous tropical microorganisms in a small-scale trial. The oil and grease content of the samples was monitored as an indication of the levels of petroleum hydrocarbon during the experiment. The indigenous enriched culture generally biodegraded the petroleum hydrocarbon to a greater extent than the commercial products and media controls early in the bioremediation process (0–5 days). However, as time progressed the extents of biodegradation were not significantly different between treatments until late in the bioremediation process (after 18 days). Of the two commercial products, one was more effective, reducing the level of oil and grease by 52.5% over the 3 week study. However, neither commercial product was able to meet the manufacturer’s stated level of 95% removal within three weeks. Commercial microbial-based bioremediation products may be used with some success in tropical environments, however location-specific trials may be required to ensure that the best commercial product is selected. As an alternative, the selective enrichment of indigenous microorganisms may result in similar performance at a reduced cost.

The rapid biodegradation of metsulfuron-methyl in contaminated soil was studied in this paper. The wheat (Triticum aestivum L.) rhizosphere was well simulated by setting up a hydroponic system that allowed the aseptic wheat root exudates flow onto columns containing soil previously contaminated with metsulfuron-methyl. The root-colonizing strain Penicillium sp. containing highly effective degrading plasmid on metsulfuron-methyl was inoculated in the soil, with the bulk and sterile ones as control. In soil from columns that received root exudates from a planted (versus an unplanted) apparatus, there was a significant increase in the growth of the tolerant fungi and the degradation of metsulfuron-methyl. On the other hand, the inoculation of Penicillium sp. also notably enhanced the degradation of the target herbicide. The extent of stimulation was more than twice of that measured in bulk soil. The fastest rate of disappearance of the xenobiotic occurred in the amended inoculated microcosms with 8.6 days of the half-life. The main types of low molecular weight organic acids and amino acids in the root exudates was determined to be oxalic acid, succinic acid and threonine, alanine, proline, methionine, lysine, isoleucine and leucine. What's more, by means of applying metsulfuron-methyl once again, the acclimated soil microorganisms with Penicillium sp. inoculation could sustainable rapid degrade metsulfuron-methyl. The results show that inoculation of the root-colonizing Penicillium sp. in wheat rhizosphere may be an effective approach for the rapid detoxification of soil metsulfuron-methyl contamination.

Substrates associated with two historic gold mining sites in north Westland, New Zealand, have locally very high arsenic concentrations (commonly 10-40 wt% As). The substrates consist of iron oxyhydroxide precipitates, and processing mill residues. Waters associated with some of these substrates have high dissolved arsenic (commonly 10-50 mg/L As). Natural revegetation of these very high arsenic sites has occurred over the past 50 years, although some areas of substrate remain bare. Revegetating species include native and adventive shrubs, adventive grasses, rushes, and mosses, and native ferns. Revegetation by higher plants follows initial colonization by mosses, and some shrubs are growing directly in high-arsenic substrate. Shrubs, especially manuka (Leptospermum scoparium), gorse (Ulex europaeus), tree fuchsia (Fuchsia excorticata) and broadleaf (Griselinia littoralis) largely exclude arsenic from their shoots (< 10 mg/kg dry weight) irrespective of the As content of the substrate. Likewise, most grasses, and reeds (Juncus spp.), have only modest As contents (typically < 100 mg/kg dry weight). However, mosses growing on high-arsenic substrates have strongly elevated arsenic contents (> 0.2% dry weight). In particular, the moss Pohlia wahlenbergii acts as a hyperaccumulator, with up to 3% (dry weight) As. Antimony (Sb) contents of all plants are about one thousandth of that of arsenic, reflecting the As/Sb ratio of the substrates. Plant establishment in the high-As substrates may be locally limited by low nutrient status, rather than arsenic toxicity. The shrubs, grasses, and reeds identified in this study are arsenic tolerant and largely exclude arsenic from their shoots so that revegetation with these species, can help to isolate the high-arsenic substrates from the surface environment. These species could be used as phytostabilisation agents on high-arsenic sites that are remote from human habitation. In contrast, the mosses, despite their high arsenic tolerance, are a less desirable component of revegetation of high-arsenic substrates because they actively transfer arsenic from the substrate to the biosphere.

Phosphorus (P) release from bottom sediments can be a significant source to the overlying water column, potentially maintaining and enhancing algal growth and eutrophic conditions in lakes and reservoirs. Thus, the objectives of this study were to: (1) measure P flux under aerobic and anaerobic conditions from intact sediment cores collected at Beaver Reservoir, northwest Arkansas, (2) evaluate the spatial variability in measured sediment P flux under aerobic and anaerobic conditions along the reservoir, and (3) compare external and internal P loads to Beaver Reservoir. Six intact sediment cores were collected at three sites representing the lacustrine, transitional, and riverine zones during June 2003, September 2003 and February 2004 and incubated for 21 days in the dark at ~22°C. Three cores from each site were incubated under aerobic conditions and anaerobic conditions. Water samples were collected from the overlying water column in each core daily for the first five days and every other day thereafter and analyzed for soluble reactive phosphorus (SRP). Water removed from the core was replaced with filtered lake water, maintaining a constant overlying water volume of 1 l. Sediment P flux under anaerobic conditions (<0.01-1.77 mg m-² day-¹) was generally greater than that measured under aerobic conditions (<0.01-0.89 mg m-² day-¹). Some spatial variability existed in sediment P flux where P flux was generally greatest at the sites in the riverine and transitional zones. Maximum sediment P flux was observed under anaerobic conditions in cores collected from the transitional zone during September 2003. Average sediment P flux under aerobic conditions (0.09 mg m-² day-¹) and anaerobic conditions (0.31 mg m-² day-¹) was greater than the external P flux (0.05 mg m-² day-¹) estimated from the Beaver Reservoir tributaries. Results showed that the annual internal P load (7 Mg year-¹) from bottom sediments in Beaver Reservoir was less than 10% of the annual external P load (~81 Mg P year-¹). The internal P load was significant, but it would not currently be cost effective to manage this P source given the large surface area of Beaver Reservoir.

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.

Over 70 wood chemical plants operated in northern Pennsylvania between ca. 1890 and 1950, all located within 72 km of the New York state border. Their original purpose was to salvage the small unwanted hardwood trees left behind by the lumber mills, and to make charcoal, calcium acetate and methanol for a number of industrial uses via destructive distillation. At many old wood chemical plant sites, unknown quantities of wood tar remain as a residual contaminant and pose a pollution threat to aquatic life in nearby streams. Research on the composition and properties of residual wood tars from five abandoned industrial sites in Pennsylvania are described. Weathered wood tars were more viscous and contained fewer volatile and semivolatile organic compounds than did soil-buried tars. Phenol, 2-methylphenol (o-cresol), 4-methylphenol (p-cresol), and 2, 4-dimethylphenol were found in all sampled tars. These water-soluble phenolic compounds were released quasi-instantaneously in aqueous solution, followed by a slower rate of release, consistent with the behavior of similar compounds in other dense non-aqueous liquids. Air-exposed wood tar deposits developed a hard crust, which contained fewer volatiles and semivolatiles and had a higher softening point than other samples. These tars eroded to form a powdered soil colonized by lichens and mosses. Residual wood tar material found at one site was shown to be thermally altered, likely during the historical destruction of the chemical plant by fire. Recovered wood tar wastes have a relatively high heating value and may have use as a potential, but limited, alternate energy source.