Studies on the progeny of rice plants grown at an unpolluted and polluted site

Oryza sativa L. cv. GR3 was grown near to a fertilizer plant and the growth of its seed progeny was evaluated at sites near to, and distant from, the fertilizer plant. The grain yield was reduced in plants grown at the polluted site, with reduced panicle length and increased sterility index. This decrease in grain yield was higher in the progeny plants than in the normal polluted plants. The polluted progeny grown at a control site showed a normal yield, but an increased sterility index. Accumulation of total sulphur and fluoride was higher in the leaves of polluted rice plants. It was evident that tolerance to air pollution was reduced in the progeny plants due to an additional dosage of sulphur and fluoride pollutants and to unfavourable climatic factors. Further, pollution effects were not carried over in progeny plants when grown in an unpolluted environment.     

An experimental investigation of the effects of nitrogen deposition to Narthecium ossifragum

Narthecium ossifragum (L.) Hudson was subjected to artificial deposition events in three experiments. In the first, a laboratory experiment, 1.0 m nitrate significantly decreased the growth of Narthecium, and the shoot and root nitrogen content of the plants was increased in all enhanced nitrogen treatments. In the second experiment, solutes were applied in situ to a relatively unpolluted upland ombrotrophic mire at concentrations measured in cloud water at a polluted site in England. There was no effect on Narthecium tissue nitrogen concentration due to either ammonium or nitrate applied alone but the shoot nitrogen was significantly increased when the ammonium and nitrate were applied in combination. In the third experiment, a piece of upland ombrotrophic mire from a relatively unpolluted site in North Wales was transplanted to a polluted site in northern England. After two years both the shoots and roots of Narthecium present in the mire showed a higher nitrogen concentration in the transplant compared with the control. These data show that nitrogen supply in the southern Pennines is supra-optimal for Narthecium, which implies that in such situations it (and other species with a similar ecological strategy) would be out-competed by more vigorous species. The data from the field experiment at the relatively unpolluted site imply that even there, nitrogen supply is close to supra-optimal for Narthecium.     

Effects of elevated CO2, nitrogen supply and tropospheric ozone on spring wheat-II. Nutrients (N, P, K, S, Ca, Mg, Fe, Mn, Zn)

CO(2) enrichment is expected to alter leaf demand for nitrogen and phosphorus in plant species with C(3) carbon dioxide fixation pathway, thus possibly causing nutrient imbalances in the tissues and disturbance of distribution and redistribution patterns within the plants. To test the influence of CO(2) enrichment and elevated tropospheric ozone in combination with different nitrogen supply, spring wheat (Tritium aestivum L. cv. Minaret) was exposed to three levels of CO(2) (361, 523, and 639 microl litre(-1), 24 h mean from sowing to final harvest), two levels of ozone (28.4 and 51.3 nl litre(-1)) and two levels of nitrogen supply (150 and 270 kg ha(-1)) in a full-factorial design in open-top field chambers. Additional fertilization experiments (120, 210, and 330 kg N ha(-1)) were carried out at low and high CO(2) levels. Macronutrients (N, P, K, S, Ca, Mg) and three micronutrients (Mn, Fe, Zn) were analysed in samples obtained at three different developmental stages: beginning of shoot elongation, anthesis, and ripening. At each harvest, plant samples were separated into different organs (green and senescent leaves, stem sections, ears, grains). According to analyses of tissue concentrations at the beginning of shoot elongation, the plants were sufficiently equipped with nutrients. Elevated ozone levels neither affected tissue concentrations nor shoot uptake of the nutrients. CO(2) and nitrogen treatments affected nutrient uptake, distribution and redistribution in a complex manner. CO(2) enrichment increased nitrogen-use efficiency and caused a lower demand for nitrogen in green tissues which was reflected in a decrease of critical nitrogen concentrations, lower leaf nitrogen concentrations and lower nitrogen pools in the leaves. Since grain nitrogen uptake during grain filling depended completely on redistribution from vegetative pools in green tissues, grain nitrogen concentrations fell considerably with severe implications for grain quality. Ca, S, Mg and Zn in green tissues were influenced by CO(2) enrichment in a similar manner to nitrogen. Phosphorus concentrations in green tissues, on the other hand, were not, or only slightly, affected by elevated CO(2). In stems, 'dilution' of all nutrients except manganese was observed, caused by the huge accumulation of water soluble carbohydrates, mainly fructans, in these tissues under CO(2) enrichment. Whole shoot uptake was either remarkably increased (K, Mn, P, Mg), nearly unaffected (N, S, Fe, Zn) or decreased (Ca) under CO(2) enrichment. Thus, nutrient cycling in plant-soil systems is expected to be altered under CO(2) enrichment.     

Antioxidant and biotransformation enzymes in Myriophyllum quitense as biomarkers of heavy metal exposure and eutrophication in Suquía River basin (Córdoba, Argentina)

We report the evaluation of changes in water quality, increasing pollution level, of a section of Suquía River basin (Córdoba, Argentina) by using Myriophyllum quitense as bioindicator in addition to the measurement of chemical parameters, combined with chemometrics (ANOVA, Cluster and Discriminant Analysis). Myriophyllum quitense was collected upstream from Córdoba city at an unpolluted site of Suquía River basin. After collection plants were transplanted to different sites with different pollution levels. Subsequent to transplantation plants were weekly collected from the original site as well as from transplantation stations. Water quality was evaluated throughout the transplantation experiment, while the use of this macrophyte as bioindicator was verified through the activation of its antioxidant defenses and biotransformation system. Myriophyllum quitense reacts to the pollution stress increasing the activity of glutathione-S-transferases (CDNB and Fluorodifen), glutathione reductase (GR) and peroxidase (POD). Elevated enzyme activities agreed to different pollution levels, especially inorganic nitrogen loads combined with elevated lead and aluminum concentrations, all of them originated by anthropogenic activities, thus presenting Myriophyllum quitense as a good biomonitor for assessment of water quality in this polluted aquatic ecosystem.     

Exposure of oats, Avena sativa L., to filtered and unfiltered air in open-top chambers: effects on grain yield and quality

Field grown oats, Avena sativa L. cv Vital, were exposed to filtered and unfiltered air from anthesis until harvest in open-top chambers at a site in south-west Sweden. Ambient plots were used to study the influence of the chamber itself. With the exception of the number of grains per panicle, which was significantly higher in the charcoal-filtered treatment, no significant filtration effects were obtained for any of the plant growth parameters studied), i.e. grain yield, number of panicles per square metre, 1000-grain weight, straw yield and harvest index.) The chamber had a significant negative effect on grain yield, 1000-grain weight and straw yield. None of the yield quality parameters that were measured, such as crude protein content, crude fibre content, fat content, volume weight of the grain and water content of the grain at harvest, were significantly influenced by either air filtration, or the presence of the chamber. The chlorophyll content of the flag leaves was higher in the charcoal-filtered treatment than in the non-filtered and ambient air treatments towards the end of the experiment, indicating that filtering of the air delayed senescence. The decline of the shoot area after the onset of plant senescence proceeded faster in both chamber treatments. The faster development in the chamber was explained by the faster accumulation of thermal time in the chamber.     

Concentration of bioactive compounds in mussels Mytilus galloprovincialis as an indicator of pollution

The polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organotins were analyzed in mussels Mytilus galloprovincialis from polluted and unpolluted sites from Mokpo Bay, Korea. The total PAH's concentrations (10(-3)mgkg(-1)) measured by GC-MS were in the range from 31+/-23 to 1+/-1. Among the eight PAHs the predominant ones were fluoranthene, phenanthrene and pyrene and accounted approximately 63% of the total PAHs. Among the four detected PCBs the highest content was of PCB 153, which accounted about 47% of the total PCBs. The main organotin compounds were dibutyltindichloride (DBT) and tributyltinchloride (TBT) and their composition was approximately 33% and 24%. PAHs, PCBs and organotins were found only in the mussels from polluted site. The antioxidant activity by ABTS [2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid)] test was higher in mussels from polluted than from unpolluted sites (P<0.05). It was found a correlation between the determined compounds (PAHs, PCBs and organotins) and the antioxidant activity of the mussel tissue from polluted site and the correlation coefficients were 0.96, 0.92 and 0.80, respectively. Such correlation can be explained by the properties of mussels. Since the mussel cell wall and tissues are hydrophobic, they can concentrate a number of hydrophobic pollutants like PAHs and PCBs from the marine environment by solubility rules. On the other hand, proteins are lipophilic compounds having antioxidant properties. Certain amino acid residues and thiol (-SH) groups, contained in proteins, respond to the ABTS antioxidant activity assay. Thus there may be a correlation between the total antioxidant activity of the organism and the PAH-PCB pollutants which were concentrated from its environment. The studied properties of mussels from polluted site can be used as an additional indicator of pollution.     

Impacts of ozone on the growth and yield of field-grown winter wheat

Seed of winter wheat (Triticum aestivum L. cv Riband) was sown on 29 August 1992 in eight field plots. Four plots were exposed to elevated ozone (O(3)) concentrations on 16 days between 29 August and 2 October 1992, for 6 h day(-1), and on 27 days between 29 March and 24 August 1993, for 7 h day(-1). Mean daily O(3) concentrations were approximately 30 and 80 nmol mol(-1) in ambient and fumigated plots, respectively. Plants were sampled on 5 November (1992), 14 January, 16 February, 1 April, 25 May, 23 June and 24 August (1993). No visible symptoms of O(3) damage or premature senescence were observed at any time over the course of the experiment. Exposure to elevated O(3) decreased the above ground biomass by reducing plant density and individual plant relative growth rate. However, there was no significant influence of the pollutant on the growth of the root relative to the shoot. Assessment of yield characteristics at the final harvest revealed an O(3)-induced decrease in the number of grains per ear, as a result of fewer grains per spikelet and an increase in the number of infertile florets per spikelet. No significant effects of the pollutant on the number of ears per plant, spikelets per ear, or 1000 grain weight were found. As a result of the combined effects on the number of grains per ear and the decrease in plant density and growth rate, O(3) exposure reduced grain and straw yields (tonnes ha(-1)) by 13 and 8%, respectively. However, no significant change in the partitioning of dry matter between the grain and the straw was observed in fumigated plots. The findings are discussed within the context of United Nation Economic Commission for Europe critical level guidelines for the protection of crop yields, in relation to their application to winter-sown crops.     

Heavy metal accumulation, heat shock protein expression and cytogenetic changes in Tetrix tenuicornis (L.) (Tetrigidae, Orthoptera) from polluted areas

The orthopteran insect Tetrix tenuicornis, collected from polluted and unpolluted areas, was used to study heavy metal accumulation and its impact on stress protein levels and on changes in the number and morphology of chromosomes in mitotic and meiotic cells. During two consecutive years, insects were collected from polluted areas of zinc-lead mine spoils near Boles?aw (Poland) and from unpolluted areas near Busko and Staszów (Poland). T. tenuicornis from the polluted area showed 1.5, 4.03, 4.32 and 41.73 times higher concentrations of copper (Cu), zinc (Zn), lead (Pb) and cadmium (Cd), respectively, than insects of the same species collected from unpolluted areas. Insects exposed to heavy metals showed only small changes, and rather a decrease in the concentration of constitutive and inducible heat shock proteins Hsp70, the level of which increases under stress conditions. A cytogenetic study of T. tenuicornis revealed intra-population anomalies in chromosome number and morphology in mitotic and meiotic cells and the presence of an additional B chromosome in germinal cells. In 50% of females collected from polluted areas, mosaic oogonial mitotic chromosome sets and diploid, hypo- or hypertetraploid, tetraploid, and octoploid chromosome numbers were detected. In turn, 14.6% of males showed a heterozygous deficiency of chromatin in L2 and M3 bivalents in addition to the presence of B chromosomes.     

Growth performance and biochemical responses of three rice (Oryza sativa L.) cultivars grown in fly-ash amended soil

The disposal of fly-ash (FA) from coal-fired power stations causes significant economic and environmental problems. Use of such contaminated sites for crop production and use of contaminated water for irrigation not only decreases crop productivity but also poses health hazards to humans due to accumulation of toxic metals in edible grains. In the present investigation, three rice cultivars viz., Saryu-52, Sabha-5204, and Pant-4 were grown in garden soil (GS, control) and various amendments (10%, 25%, 50%, 75% and 100%) of FA for a period of 90 days and effect on growth and productivity of plant was evaluated vis-a-vis metal accumulation in the plants. The toxicity of FA at higher concentration (50%) was reflected by the reduction in photosynthetic pigments, protein and growth parameters viz., plant height, root biomass, number of tillers, grain and straw weight. However, at lower concentrations (10-25%), FA enhanced growth of the plants as evident by the increase of studied growth parameters. The cysteine and non-protein thiol (NP-SH) content showed increase in their levels up to 100% FA as compared to control, however, maximum content was found at 25% FA in Saryu-52 and Pant-4 and at 50% FA in Sabha-5204. Accumulation of Fe, Si, Cu, Zn, Mn, Ni, Cd and As was investigated in roots, leaves and seeds of the plants. Fe accumulation was maximum in all the parts of plant followed by Si and both showed more translocation to leaves while Mn, Zn, Cu, Ni and Cd showed lower accumulation and most of the metal was confined to roots in all the three cultivars. As was accumulated only in leaves and was not found to be in detectable levels in roots and seeds. The metal accumulation order in three rice cultivars was Fe > Si > Mn > Zn > Ni > Cu > Cd > As in all the plant parts. The results showed that rice varieties Saryu-52 and Sabha-5204 were more tolerant and could show improved growth and yield in lower FA application doses as compared to Pant-4. Thus, Sabha-5204 and Saryu-52 are found suitable for cultivation in FA amended agricultural soils for better crop yields.     

Risk assessment of heavy metal pollution for detritivores in floodplain soils in the Biesbosch, The Netherlands, taking bioavailability into account

Floodplains of the European rivers Rhine and Meuse are heavily polluted. We investigated the risk of heavy metal pollution (Cd, Cu, Pb, Zn) for detritivores living in a floodplain area, the Biesbosch, the Netherlands, affected by these rivers. Total soil, pore water and 0.01 M CaCl(2) extractable concentrations and concentrations in plant leaves, earthworms, isopods and millipedes were measured in two sites and compared with literature data to assess possible risks. Based on total metal concentrations in soil, serious effects on detritivores were expected. However, 0.01 M CaCl(2) extractable, pore water and plant leaf concentrations were similar to metal concentrations found in unpolluted areas. Concentrations of Cu and Cd in earthworms and Cu in millipedes were higher in the Biesbosch than in animals from reference areas. All other measured concentrations of heavy metals in earthworms, isopods and millipedes were similar to the ones found in reference areas. Despite high total soil concentrations, effects of Zn, Cu, Pb and Cd pollution on isopods are therefore not expected, while millipedes may only be affected by Cu. Since Cu and Cd levels in earthworms were increased compared to animals in unpolluted soils, this faunal group seems to be most at risk. Given the engineering role of earthworms in ecosystems, effects on the ecological functioning of floodplain soils therefore cannot be excluded.     

ELISA detection of multixenobiotic resistance transporter induction in indigenous freshwater Chironomidae larvae (Diptera): A biomarker calibration step for in situ monitoring of xenobiotic exposure

A new simple and sensitive method to distinguish chemically polluted from unpolluted situations in freshwater ecosystems is reported. For this purpose, Chironomus gr thumni larvae were collected from a polluted urban river downstream a sewage treatment plant. For the first time, ELISA assay was used to semi-quantify the multixenobiotic resistance transporters (MXR) in these small pertinent bioindicators. The use of samples immediately fixed in the field gives a delay to isolate larvae and allows multi-sampling along a longitudinal transect in a river at a given time. Results exhibit an induction of MXR proteins in larvae from the polluted river and a deinduction in larvae maintained 11days in unpolluted water. They show new evidences to use midge larvae in biomonitoring environmental programs. They answer to first biomarker calibration steps for the ongoing development of MXR transporters as a detection tool of xenobiotic impacts on bioindicator invertebrates in their freshwater habitats.     

Height growth of different European Scots pine Pinus sylvestris L. Provenances in a heavily polluted and a control environment

Results are presented of height measurements and degree of needle injury on five-year-old plants of Scots pine (Pinus sylvestris L.) growing near a phosphate fertiliser plant that emits SO(2) and fluorides. The populations of Scots pine represented in this experiment originate from 11 countries and were substantially differentiated in height growth and extent of needle necroses. Those populations which grew most rapidly were found to be the most sensitive to pollutant injury. The least productive provenances from the north of the range (Sweden, USSR) are at the same time characterized by lowest decline in height growth, lowest mortality and least extensive necroses. It is proposed that gene banks be established for the best genotypes likely to be eliminated in the heavily polluted conditions of Poland today.     

Seasonal changes in the sulphate content of deciduous woodland soils exposed to atmospheric pollution

Seasonal changes in soil pH, sulphate concentration and total-S were measured in two brown earth soils, sampled from deciduous woodlands. One site studied was exposed to severe atmospheric pollution from a coking works while the other site was relatively unpolluted but located in an area receiving wet and dry deposited acidity of greater than 1.0 and 2.4 kg H(+) ha(-1) year(-1), respectively The pH of soil at the heavily polluted site was lower than the relatively unpolluted soil at each monthly sample point, except during November. Annual average sulphate concentrations (LiCl-extractable) were highest in the soil exposed to coking pollution, where they peaked during summer and autumn. A marked difference in total-S was found in soils from the two sites, the heavily polluted soil showing the highest concentration with peaks again occurring during late summer and autumn. Only 4.0% (w/w) of the total-S of the heavily polluted soil occurred as LiCl-extractable sulphate, compared to 21.4% (w/w) for the relatively unpolluted soil, showing that organic sulphur is increased in brown earths following exposure to severe atmospheric pollution from the coking works.     

Effects of air filtration on spring wheat grown in open-top field chambers at a rural site. I. Effects on growth, yield and dry matter partitioning

Spring wheat, Triticum aestivum, was grown in open-top field chambers and exposed during the whole life cycle to filtered and non-filtered ambient air. The relatively low ambient pollution level did affect plant growth but had no effect on the overall grain yield of the two spring wheat cultivars Echo (1987) and Pelican (1988). A reduced root growth was found in both years which could be attributed mainly to the deposition of NO2 and SO2. Effects on crop development most likely due to ozone were limited to the 1987 growing season during which the ambient ozone concentrations were enhanced compared to 1988. This resulted in a slightly increased grain harvest index, a reduced 1000-grain weight, straw yield and a greater reduction in root growth. Visible damage resembling ozone injury appeared both years during seedling growth.     

Spatial and temporal variations and mobile source emissions of polycyclic aromatic hydrocarbons in Quito, Ecuador

Motor vehicles are a major source of air pollution in Quito, Ecuador; however, little work has been done to characterize spatial and temporal variations in traffic-related pollutants, or to measure pollutants in vehicle emissions. We measured PAH continuously for one year at two residential sites in Quito, and PAH and traffic patterns for one week near a busy roadway. Morning rush-hour traffic and temperature inversions caused daily PAH maxima between 06:00 and 08:00. SO₂, NO_x, CO, and PM_2.5 behaved similarly. At the residential sites PAH levels during inversions were 2-3-fold higher than during the afternoon, and 10-16-fold higher than 02:00-03:00 when levels were lowest. In contrast, at the near-roadway site, PAH concentrations were 3-6-fold higher than at the residential sites, and the effects of inversions were less pronounced. Cars and buses accounted for >95% of PAH at the near-roadway site. Near-roadway PAH concentrations were comparable to other polluted cities.     

Effects of pollution on humic substances

To assess effects of industrial and environmental pollution on analytical characteristics of humic substances, we isolated humic acids (HA's) and fulvic acids (FA's) from unpolluted and polluted soils and sediments. Following purification, the HA's and FA's were characterized by elemental (C, H, O, N, S) and functional group (CO2H, phenolic OH, total acidity) analyses, infrared (IR) spectrophotometry, differential thermal analysis (DTA) and by metal (Fe, Al, Cu, Mn, Pb, Ni, Co, Zn, Cr, Cd, Hg, Ca and Mg) analyses. Si was also determined in all samples. Polluted HA's and FA's contained more N and S but less O and were richer in all metals and Si than were unpolluted ones. IR spectra showed that polluted humic materials were enriched in COO- groups, secondary non-cyclic amides and possible also in SO3H groups. DTA curves indicated that polluted HA's and FA's were more thermostable than unpolluted HA's and FA's. Unusually high N, S, Cu, Cr, Zn and Hg contents of humic materials appear to be useful indicators of soil and sediment pollution.     

The fate of some components of acidic deposition in ombrotrophic mires

The ability of ombrotrophic Sphagnum species to immobilise inorganic nitrogen deposited from the atmosphere was investigated in a series of simple lysimeter experiments. In an unpolluted mire, Sphagnum fuscum mats retained all the nitrogen deposited to them in natural precipitation events. Sphagnum capillifolium mats, transplanted from an unpolluted site to the polluted southern Pennines in England, also initially retained a large proportion of deposited nitrate and ammonium. However, a laboratory experiment demonstrated that high rates of nitrogen supply cause a loss of the ability of the moss to retain nitrate, which suggests that this may occur as a result of increased nitrogen deposition in polluted regions, resulting in increased nitrate availability in the peat. Investigation of the volume of precipitation and amounts of sulphate and chloride passing through the Sphagnum mats in the southern Pennines, as compared to that collected in adjacent bulk deposition gauges, showed that conventional deposition monitoring grossly underestimates rates of deposition to vegetation. Efficient trapping of occult and dry deposition by the moss led to much greater volumes of precipitation and amounts of sulphate and chloride being measured in throughflow than in bulk precipitation samples. Physiological response of S. fuscum to occult precipitation and heavy rainfall was investigated by measuring nitrate reductase activity induced in the moss by nitrate supplied in 'fine mist' and 'large droplet' applications of solutions to moss in the field. Greater response was shown to occult deposition, suggesting that this form of precipitation may be important in vegetation damage in polluted regions.     

The relationship of root porosity and radial oxygen loss on arsenic tolerance and uptake in rice grains and straw

The correlations among arsenic (As) accumulation in grains and straw, rates of radial oxygen loss (ROL), and porosity of roots using 25 rice cultivars were investigated based on two pot experiments: (1) soil with addition of 100 mg As kg^?1 for analysis of As in grains and straw, and (2) deoxygenated solution for analyzing rates of ROL and porosity of roots. The results showed that there were great differences in grain As (0.71–1.72 mg kg^?1) and straw As (15.6–31.7 mg kg^?1), rates of ROL (7.40–13.24 mmol O₂ kg^?1 root d.w. h^?1), and porosity (20.91–33.08%) among the cultivars. There were significant negative correlations between As in grains or straw and ROL and porosity, and significant positive correlations between rates of ROL and porosities, respectively. Rice cultivars with high porosities tended to possess higher rates of ROL, and had higher capacities for limiting the transfer of As to aboveground tissues.     

Tradescantia pallida cv. purpurea boom in the characterization of air pollution by accumulation of trace elements

Tradescantia pallida cv. purpurea, a plant species widely employed for ornamentation in Brazil, has been successfully used for monitoring the genotoxicity of various agents by the micronucleus assay. To amplify knowledge about its suitability as a bioindicator species, its capacity for accumulating trace elements from urban air pollution was evaluated. T. pallida was rooted using standardized soil, and the vases were distributed in two highly polluted sites of the urban area of S?o Paulo, Brazil (Cerqueira Cesar and Congonhas districts), and in one unpolluted control site situated approximately 50 km from downtown S?o Paulo (in Caucaia do Alto). Approximately six months after exposure to pollutants, adult leaves of this plant were collected monthly for 12 months. The leaves were washed with deionized water, dried, and ground for analyses. Characterization of element levels was carried out by neutron activation analysis. Powdered samples and standards were irradiated at the IEA-R1 nuclear reactor for short and long periods, and concentrations of As, Ba, Br, Ca, Ce, Cl, Cr, Co, Fe, K, La, Mn, Na, Rb, Sb, Sc, Sr, Th, and Zn were determined. Analysis of variance applied to the results indicated that samples from polluted sites present the highest concentrations of Ba, Ce, Cr, Co, Fe, La, Sb, and Sc (p < 0.05). Discriminant analysis revealed that it was possible to distinguish the two polluted areas with a precision of 97.5%, based on the amount of pollutant elements measured in the plants at each site. The results indicated the potential use of T. pallida as an accumulator plant for air pollution biomonitoring.     

Cu and Zn mobilization in soil columns percolated by different irrigation solutions

We investigated the effects of different concentrations of nitrate and ammonium in irrigation water on the mobilization of Zn and Cu in repacked soil columns with a metal-polluted topsoil and unpolluted subsoils over two and a half years. Soil solution samples were collected by suction cups installed at vertical distances of a few centimeters and analyzed for dissolved organic carbon (DOC), Cu, and Zn (total and labile). During high N treatments the pH decreased and the presence of exchangeable cations resulted in Zn mobilization from the surface soil. The nitrogen input stimulated the biological activity, which affected both concentration and characteristics of DOC and consequently Cu speciation. Metal leaching through the boundary between the polluted topsoil and the unpolluted subsoils increased soil-bound and dissolved metals within the uppermost 2 cm in the subsoils. Our study shows that agricultural activities involving nitrogen fertilization can have a strong influence on metal leaching and speciation.