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Soils can act as a sink for anthropogenic and naturally released heavy metals. Among these are heavy metal oxides and sulfides, which are emitted e.g. by mining industry and metal smelting. The dissolution and transformation behavior of these heavy metal phases specifies their fate in the soil and determines whether the metals become bioavailable or could contaminate the groundwater. To gain more information about these dissolution reactions in soils, in-situ methods are needed. We present here a method to fix particulate metal phases on an inert support. This method allows us to expose and recover metal phases in the environment under controlled conditions.

Acrylic glass was chosen as inert polymer substrate for the heavy metal phases as it is stable to weathering. Epoxy resin was used as adhesive film between the acrylic glass support and the heavy metal coating. The fine-grained heavy metal phases are applied onto the epoxy resin using a dust spray gun. The heavy metal coated polymer platelets can be inserted in a controlled way into selected soil profiles and be recovered after definite time intervals. Qualifying and quantifying analysis can be carried out on every single polymer support.

A portable low cost micro total analytical system (μTAS) is described for the environmental analysis of metal cations in natural waters using luminol chemiluminescence. Every element of the analysis can be performed on these devices therefore producing a portable laboratory that can be used for analysis. Miniaturising these devices brings several advantages including low reagent consumption, low volumes of waste produced and an increased in performance. The ability to scale out these devices and produce many low cost μTAS creates a network of in-situ sensors that can provide greater spatial and temporal information for an environmental system. Chemiluminescence is a promising method of detection for μTAS due to its high sensitivity and the simplicity of the measurement technique.

The experimental implementation of Diffuse Infrared Fourier Transform Spectroscopy (DRIFTS) to the study of carbonaceous materials and catalysts is discussed in detail. Analytical methods used to sample and optimize the quality of infrared spectra processing are outlined. Several examples demonstrate the feasibility of this technique in the field of adsorption and catalysis: An in-situ spectroscopy is applied to the elucidation of the oxidation mechanisms occurring during the treatment of a cellulose char under air; the type of interactions occurring between adsorbed methanol or impregnated copper salts with carbonaceous materials was considered with respect to char surface chemistry; the mode of adsorption of several aqueous organic adsorbates on titanium oxide was investigated.

In recent years, various mass-spectrometry procedures have been developed for identifying bacteria. The accuracy and speed with which data can be obtained by Matrix-assisted Laser Desorption/Ionization Time-of-flight Mass Spectrometry (MALDI-TOF MS) make this an advantageous technique for environmental monitoring. However, minor variations in the sample preparation can influence the mass spectra significantly. In the present study, we have introduced a procedure to prepare bacteria by microextraction and we have optimized experimental parameters for rapid identification by MALDI-TOF MS of whole bacterial cells isolated from environmental samples such as wastewater and soil.

Groundwater in the Maresme area (NE Spain) is characterised by high concentrations of nitrate, sulphate and chloride. Chemical and isotope data presented in this paper were collected in order to characterise the main sources of nitrate contamination. This study has also provided information about sources of sulphate and chloride in the area. The nitrate groundwater contamination is related to agriculture activities such as the intense use of synthetic fertilisers. The high rates of fertilisation and re-circulation of the shallow groundwater used for irrigation explain the high concentration of nitrates in the groundwater with values as high as 482 mg l. The isotope composition of the groundwater nitrate ranges between +6.8‰ and +9.4‰ for N and from +5.1‰ to +10.2‰ for O. Fertilisers used in the area show values close to 0‰ and +23‰ for N and O, respectively. The more enriched N values in the groundwater compared to the fertilisers is associated to volatilisation of the ammonia component of the fertilisers. The O pattern in the groundwater implies that nitrate from nitrogenous fertilisers is recycled in the soil where it becomes O depleted. Based on the N and O data, a significant denitrification was discarded in the study site. Groundwater dissolved sulphate has S values between +5.8 to +7.0‰ suggesting that the main source of sulphate might not be related to seawater intrusion, which in turn questioned the origin of chloride previously related to a seawater intrusion.

This paper summarizes the application of isotope hydrological tools to infer water sources in different parts of the Souss-Massa region of Morocco. The oxygen-18 (O) isotopic data show a variation between −7‰ upstream and −4‰ downstream, with intermediate values in the medium part of the plain. The upstream watershed, which is the place of condensation and the beginning of the Atlas Mountain, shows more characteristic H and O-depleted waters. This finding can be explained by the altitude and the continental effects. On the other hand, H and O-enriched waters values towards the ocean show an evaporation effect near the condensation source or the irrigation returns, notably in the irrigated perimeters. The rain isotope values indicate a main recharge from the Atlasic Mountain, whereas the contribution of the local rains is negligible in downstream. The H-O relationship displays straight lines with variable slopes on an upstream-downstream movement. The slopes, which are below 8 in certain areas, represent the evaporation during the infiltration either by runoff or by irrigation returns. Besides, the different values of slopes correspond to the variables isotopic values observed at a regional scale within the basin.

Three carbon isotope profiles, from the raised Polish peat bogs Zieleniec, Szrenica, and Suche Bagno, representing the last millennium, have been analysed. C in the peat profiles varies from −31 to −22‰. C changes were found similar in the horizons of various cores. We suggest that variation in C of peat is dominantly governed by variations in temperature of vegetation period of composing given strata. It is also shown, that an increase of 1 °C of the vegetation temperature results in the of about −0.6‰ of C. Based on C isotope calibration, the following sequence in the climate variations between 600 and 1950 in Poland is proposed: a cold period from 600 to 1050, a very cold period from 1050 to 1200, a very warm period corresponding to the “Little Climatic Optimum” (Matthes 1939) from 1200 to 1550, a very cold period corresponding to the “Little Ice Age” from 1550 to 1820 and a warm moderate period corresponding to the “Global Climatic Warming” from 1830 to 1960.

A high-precision method for determining the isotopic composition of cadmium (Cd, Cd, Cd, Cd) has been developed and applied to study natural and anthropogenic materials such as sedimentary rocks, soils, corals and mining waste. Preliminary results obtained on sedimentary rocks, e.g. jurassic limestone, shale and greywacke, suggest the existence of natural variations in Cd isotopic ratios. The origin of this variation is likely to result mainly from a mass-dependent isotopic fractionation process. It is suggested that variation in the isotopic composition of Cd may also occur in materials of anthropogenic origin. Very low Cd concentrations (about 10 ppbw) are reported for the clastic rocks, whereas the limestone displays a much higher concentration (75 ppbw), suggesting that Cd may be trapped during diagenesis.

The contamination of soils and sediments by carbonaceous particles has been investigated by organic-petrological methods. Results from the study of soils from industrialised areas show that airborne contaminants like brown coal, hard coal, charcoal, and char have accumulated. The observed soil contamination is due to dust emission by open-cast brown coal mines, to the burning of brown coal and hard coal, and coking plants. It was found that soil contamination can occur over a distance of several dozen km from the contamination sources. The investigation of soils and sediments demonstrates the heterogeneous character of organic matter and proves the presence of coal and charcoal particles of fossil origin in the majority of the samples. The heterogeneity of the organic matter is found responsible for variations in the sorption behaviour of organic pollutants like polycyclic aromatic hydrocarbons in soils and sediments.

When preparing field samples for analysis and testing, it is invariably necessary to split the sample into representative subsamples. If the mass of the original sample is of the order of 1 000 kg (dry-mass basis), then subsamples that are about 100 000–1 000 000 000 times smaller are required for chemical analysis. With such large reductions in size, the representability of the subsample is a concern. Here, a systematic method for preparing representative subsamples from large quantities of wet sediment is described. The sediment is passed through a commercially available slurry sampler that provides 1/20 splits. Further splits are obtained with a custom-built churn splitter. The procedure was applied to sediments collected from Lake Ontario, USA, and from the lower Fox River and Green Bay, Wisconsin, USA. Its efficacy was evaluated by dioxin and total-organic-carbon analy- sis for the sediments from Lake Ontario and by analysis of the ammonia contained in the pore-water of the sediments from the Fox River and Green Bay.