In Europe more than 2,500 lysimeters operated by research institutes and industry (Lanthaler 2005). Originally lysimeters were built for investigations of soil water and solutes, nutrient leaching and pesticide degradation (see e.g. Winton and Weber 1996). Currently lysimeters additionally used as a tool for investigations on biological processes, and structural changes of plants, including root distribution, and enzyme activities etc. (see e.g. Dizer et al. 2002; Schloter et al. 2005).

The present paper describes the results of experiments with measurements of heavy metals concentrations in soil, leaves and roots of Zea mays cultivated near the major road in the area Araxos, Greece. The chain of ecological interactions is decomposed into individual subsystems with sufficiently small number of data samples describing concentrations of elements. The GMDH-based regression models are obtained and analyzed to assess different aspects of interactions within the chain “soil-roots-leaves”. The paper also represents a qualitative assessment technique to simplify analysis of the results, as well as to generalize the modeling results for different subsystems to the whole system.

Persistently high Nitrogen (N) deposition may have caused widespread N saturation in Central Europe's forests. Simple and inexpensive methods are required for estimating the N status. This study suggests that the current N status of forest ecosystems can be estimated by measuring CaCl₂-extractable nitrate concentrations in the soil below the main rooting zone. We tested this possibility using a large number of samples (135 in total) in a nested sampling design in two homogeneous Norway spruce forests in southern Bavaria. This approach was accompanied by a small scale survey with suction cups (N = 54) in one forest. Nitrate concentrations determined by soil extracts varied widely (coefficients of variance 95 and 125%) and were well comparable with those of the simultaneous investigation of seepage water. Site and stand conditions explained only a small portion (<10%) of the total variation. Mineral soil nitrate concentrations were not spatially dependent at the medium and large scales (about 10 m to several km) in both forests. Therefore the reliability of estimates at these scales depends mainly on the sample size. At the small scale (<about 10 m) large variation in nitrate concentrations and a considerable spatial dependency could be observed. Therefore intensive sampling is necessary at short distances in order to estimate the mean adequately. From our results, we deduct possibilities and limitations of nitrate inventories as a tool for regional assessment of the N status of forests.

The mass, ionic and elemental size distributions of particulate matter (PM) measured indoors and outdoors in an apartment situated in a north-westward suburb of Prague are presented. The PM samples were collected by two Berner type low pressure impactors separating particles into 10 size fractions from 26 nm to 10 μm and were further analyzed by ion chromatography (IC) and proton induced X-ray emission (PIXE). Temperature, pressure and relative humidity were measured both indoors and outdoors parallel to PM sampling. The indoor and outdoor PM dynamics were recorded by two scanning mobility particle sizers (SMPS) and an aerodynamic particle sizer (APS). Finally, the ventilation rate was determined by a radon technique. Ion chromatography showed that the major inorganic components of the fine particle mode are sulfate, nitrate, and ammonium with very low indoor nitrate concentration. Crustal elements (Al, Si, Ca, Ti, Mn, and Fe) were associated with the coarse aerosol mode. The presence of people increased the mass concentration of coarse particles, whereas cooking, smoking, and burning of incense and candles contributed predominantly to the fine particle mode. Smoking and the burning of incense also increased the concentration of potassium, bromine and chlorine content in fine particles.

Several lysimeter scenarios and approaches exist to study the fate of agro-chemicals or contaminants from deposition in soil columns. In many systems just transport and leaching of the parent compound is followed, in some systems the leaching and transport of the metabolites is investigated as well. In more sophisticated lysimeter systems the volatilization and also the mineralization of the applied chemicals can be additionally monitored. Depending on the lysimeter system used and on the fact whether the applied chemicals are ¹⁴C-labeled or not, different results and various interpretations of the results might be achieved. Different lysimeter systems are described in this paper and a real dataset of a specific lysimeter experiment was transferred and evaluated in a virtual approach in the different lysimeter systems in order to show the advantages and disadvantages of the various systems.

Aqueous phase adsorption of three textile dyes onto a granular activated carbon produced from acid activation of almond shells is presented. Primarily, the sorption of three basic dyes, methylene blue, rhodamine b, and malachite green oxalate were studied. Four models, the Freundlich, the Langmuir, the Redlich-Peterson, and the Toth isotherms were compared for their quality of fit to the single-solute sorption data. Next, sorption of the three likely binary systems was examined. Four bi-solute models, the extended Langmuir with and without an interaction term, the extended Redlich-Peterson with an interaction term, and the empirical extended Freundlich model were used to predict sorption in the binary systems. Nonlinearly determined constants of the corresponding single-solute isotherms were used in the binary models to compare with experimental binary sorption data. For the single-solute system, the three-parameter models of the Redlich-Peterson and the Toth isotherms outperformed the Langmuir and Freundlich models. The empirical extended Freundlich model produced the closest comparison to the binary data in each system. In general, the nonlinear method provided a simple and computationally effective technique of producing optimal fitting parameters for the bi-solute sorption models.

In this study, heavy metal content (Cr, Cu, Mn, Ni, Zn) was determined in sediments and different organs of Rumex obtusifolius L. and Polygonum lapathifolium L. (Polygonaceae), Urtica dioica L. (Urticaceae) and Xanthium strumarium L. (Asteraceae) species. These species grow ubiquitously and vigorously on the periodic flooding areas of Nilüfer stream which have been polluted by different local industrial activities. Below and above-ground parts of plant samples and their sediments were analyzed by ICP-MS for their elemental contents. In general, the variations in the heavy metal content in sediments are reflected in heavy metal status of plant organs. However, this variation depends on plant species and heavy metals. R. obtusifolius, U. dioica and X. strumarium species have elevated levels of Cr, Cu, Ni, and Zn whereas Mn was observed only in P. lapathifolium. The contribution of different organs to the accumulation capacity of the total phytomass is specific to species.

Acid mine drainage (AMD), a legacy of coal and mineral extraction, contaminates streams with complex mixtures of acid and heavy metals that are usually partitioned between the water column and substrate. Understanding the conditions under which sediments retain toxicity after the water column is cleared is important for predicting the long term success of remediation efforts. We conducted laboratory and field experiments to evaluate the relative contribution of acidity versus metals to the toxicity of AMD contaminated sediment towards aquatic macroinvertebrates. Laboratory bioassays showed that precipitate-coated substrate from AMD-impacted sites were toxic to Ctenodaphnia magna and reduced growth of mayflies (Ephemeroptera: Heptageniidae). Toxicity correlated more with acidity released from the sediment than with metals. After transplantation to a clean stream, the same Al- and Fe-contaminated substrate were not toxic to daphnia and was readily colonized by benthic macroinvertebrates within 5 weeks.

Historic and current agricultural and industrial activities have resulted in accumulation of Cd, Cu, Pb and Zn in soil. To estimate potential risks for ecosystems, agriculture and water quality, an integrated risk assessment was performed for The Netherlands. Risks of metal contamination were assessed on a national scale by comparing present soil concentrations of Cd, Pb, Cu and Zn with critical concentrations of those metals in view of agricultural impacts, ecological impacts and impacts on the quality of groundwater and surface waters. Results show that present soil metal concentrations cause few risks for agriculture or ecosystems; for less than 2% of the surface area present metal levels exceed critical limits. Critical limits for groundwater are only significantly exceeded for Pb (17% of the area), but critical limits for surface water are exceeded throughout the country for Cu and Zn. Taking critical limits used in The Netherlands, the area where exceedances take place is nearly negligible for Cd and low for Pb (less than 3%), but much larger (between 40% and 50%) for both Cu and Zn. Results from this study suggest that accumulation of heavy metals in Dutch soils at present primarily affects the quality of surface waters. This stresses the need for harmonization of soil and water policy. Measures to reduce the load in surface waters to meet target levels, under conditions like those prevailing in The Netherlands, are bound to have an impact on land management.

Lentic wetlands are usually regarded as the most important natural freshwater sources of methane (CH₄) and nitrous oxide (N₂O) to the atmosphere, and very few studies have quantified the importance of lowland streams in trace gas emissions. In this study, we estimated fluxes of CH₄ and N₂O in three macrophyte-rich, lowland agricultural streams in New Zealand, to place their trace gas emissions in context with other sources and investigate the value of minimising their emissions from agricultural land. All three streams were net sources of both gases, with emission of CH₄ ranging from <1 to 500 μmol m-² h-¹ and of N₂O ranging from <1 to 100 μmol m-² h-¹ during mid-summer. For CH₄, both turbulent diffusion across the surface and ebullition of sediment gas bubbles were important transport processes, with ebullition accounting for 20-60% of the emissions at different sites. The emissions were similar on a per area basis to other major global sources of CH₄ and N₂O. Although small on a catchment scale compared to emissions from intensively grazed pastures, they were significant relative to low-intensity pastures and other agricultural land uses. Because hydraulic variables (viz. depth, velocity and slope) strongly influence turbulent diffusion, complete denitrification can best proceed to N₂ as the dominant end-product (rather than N₂O) in riparian wetlands, rather than in open stream channels where N₂O fluxes are sometimes very large.