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There is no clear answer to the question as to what kind of humic substances (HSs) (fulvic acids (FAs) or humic acids (HAs)) is primarily responsible for colour of water in water bodies. To resolve this problem, the purpose of this paper is to compare optical properties of the samples of river water with solutions (considered as standard) containing HAs and FAs in different concentrations.

The author sampled two typical unpolluted rivers of Karelian Isthmus (Leningrad Region, North-Western Russia) with different water colours – Vyun with light-brown water and Kivioja with dark-brown water.

It is revealed that the shape of the light absorption curve for both rivers is similar to that of FAs. Among the coefficients, a 364 * is unsuitable for differentiation between HAs and FAs due to its wide transgression. In contrast, the E₅₄₀ coefficient allows one to separate these groups of HSs very well. The E₅₄₀ values of the river water samples categorise them as FAs. The values of a 440 * indicate that river waters, especially from Kivioja, contain FAs with a large molecular weight in comparison with soil FAs (up to 1.75-fold higher). It shows a distinct character of river water HSs, which is consistent with the published data.

The results outline a more direct approach to decision support in the sphere of ecological monitoring of river water.

The author has concluded that river waters are coloured by FAs.

Brazilian sediment quality criteria were established based on pseudo-total metal contents, which is not suitable to determine their bioavailability and the ecological risk for aquatic biota. Therefore, the geochemical speciation of five metals (Cu, Fe, Ni, Pb and Zn) was determined to assess the distribution and ecological risk of sediments in a tropical shallow reservoir from Brazil. The paper aims to discuss these issues.

A survey of metals in ten representative stations of surface sediments (0-20 cm) from Carlos Botelho (Lobo-Broa) Reservoir was conducted during the dry season in April 2014. Sediment parameters were measured in situ. The geochemical speciation of metals was carried out using the modified three-stage BCR-701 procedure (Davutluoglu et al., 2011) and compared with pseudo-total metal contents.

Contamination at S-1 and S-8 was more severe than other sampling sites, especially for Cu, Ni, Pb and Zn. Metals such as Cu, Ni and Zn occasionally may be associated with adverse biological effects based on the comparison with sediment quality guidelines. The risk assessment code suggests no risk for Fe and low risk for Cu and Ni.

Geochemical speciation of metals could be useful in developing effective management strategies to control metal pollution in the Lobo-Broa Reservoir. Substantial amounts of Pb (classified as medium risk) were bound to humic substances and/or insoluble metal sulfides, and could pose serious risk to the benthic community through the food chain. Zinc at S-1, S-3 and S-8 showed high risk, indicating that an appreciable portion of Zn could be available to aquatic biota.

Reviews some of the chemistry and environmental hazards associated with chlorine and bromine compounds when used as water disinfectants in many industrial processes. Lays emphasis on the oxidation of bromide by chlorine to bromate, a suspected genotoxin. A risk assessment of the predicted presence is detailed. In view of the formation of haloforms and other noxious substances derived from chlorine, some of the advantages of the use of chlorine dioxide are detailed. Proposes recommendations for water regulators to consider the inclusion of bromine‐containing substances, and in particular bromate, in forthcoming legislation.

This paper aims to define and theoretically analyse the performance of modern methods investigated to speed up the recultivation process of degraded areas, and apply it into the mining basin, open pit mines, tailings and all other areas, which need environmental quality improvement.

This paper presents methods of conservation and substitution of natural resources for the purpose of faster land recultivation (reclamation) in degraded coal mine areas. Two types of methods have been developed: forest slope recultivation and agricultural recultivation of flat landfills. Indicators of positive changes include: changes in chemical properties of tailings, increase in biogenic properties and changes in biodiversity.

The research results show that the application of these methods, along with the holistic approach and adequate investment, can significantly contribute to the length of recovery process and accelerate it.

Mining basin Kostolac is used as a model test. The results can be applied on all mining basin, open pits and any degraded area.

All results and conclusions were drawn, based on the original measurements and experiments. Stake holders, wanting to manage environmental quality after exploitation in mining basin, applying those methods, can find the value of this paper.

Supporting many policies of contaminated sites management, the risk assessment methodology needs a deep knowledge of the characteristics of the contamination of soils. Physico‐chemical analysis has to take in account the heterogeneity and the specificity of the soil. A better knowledge of the interactions between the chemical substances and the matrix should be developed and its influence on the measurement chain shall be determined. In particular, the influence on the final result of each of the analytical steps (pre‐treatment, extraction, purification, analysis) has to be quantified. An experimental protocol has been designed to study the influence of the type of pre‐treatment chosen in relation to the characteristics of the matrix of real contaminated soils by PCB and PAH. The results show and quantify how the texture, the granulometry, the water content and the total organic carbon (TOC) content may affect the analytical result depending on the analytical pre‐treatment‐step chosen.

The purpose of this paper is to compare trophic characteristics of the ecosystems of small and shallow lakes with a different character of land-cover in their catchments (as exemplified by several previously unstudied lakes of the Leningrad Region, North-Western Russia, that belong to a single lake-river system).

The key limnetic parameters of four lakes are analysed. Two of the lakes are located on the territory of allotment gardens, the other two are in the forest-covered areas. A preliminary assessment was made for the production-to-destruction ratio in the ecosystems of the lakes of the study region and their vulnerability factors.

For the lakes with a largely unexploited catchment, humus of terrigenous origin can act as a “hidden” source of nutrient load (primarily as phosphates). For the lakes with a catchment occupied by allotment gardens, an elevated trophic status and intensive overgrowth by vegetation (floating forms) is driven by an increased nitrogen load.

The results can be used for planning land and water management activities in North-Western Russia and in other world’s regions with similar environmental conditions.

These results can lay a foundation for creating a region-specific model to predict trends in eutrophication and overgrowth of small shallow lakes.

We tend to take water for granted in Britain: we automatically assume that we can drink any water from a tap. In general there seems little doubt that our mains water is of an adequate standard despite much press speculation about our ageing system of water mains and the crumbling sewers. There are, however, a few points to be made.

The purpose of this paper is to evaluate the effects of two vermicompost and urea on basil (Ocimum basilicum L.) variety Catamarca INTA (wide leaf) seed production, observing the evolution of the inflorescence and seed coloration.

Treatments consisted of 50 per cent vermicompost from rumen content: 50 per cent soil (RCV); 50 per cent vermicompost from rabbit manure: 50 per cent soil (RMV); urea 100 kg/ha and soil as control. On three dates the authors determined the total number of inflorescences, harvested inflorescences and number of whorls with black seeds. In the final cycle the authors determined the weight of 1,000 seeds and the number of harvested seeds.

In general, vermicompost produced better results (p<0,0001): the total number inflorescences and whorls with black seeds and the number of seeds produced were significantly higher in vermicompost compared with those under the urea and control treatments. There were no significant differences in the weight of 1,000 seeds.

The use of chemical fertilizers causes environmental pollution, produces negative effects on human health and contributes to the depletion of non‐renewable natural resources.

These renewable amendments (vermicompost) constitute a sustainable alternative to the use of urea for inflorescence production and mature basil seed production.

The purpose of this paper is to investigate the performance of biochar and fine filtralite as a polishing filter material in further removing organic matter, phosphorous, nitrogen, turbidity and indicator microorganisms from effluents of a compact greywater treatment plant (GWTP).

A filtration experiment was carried out using columns filled with biochar and fine filtralite as filter material and unfilled column as a control. The effluent from the GWTP was pumped using a peristaltic pump at a rate of 280 l/m2-d and was fed in upward flow into the columns. The quality parameters of the raw greywater, effluents from the GWTP and the polishing columns were studied for six months of operation period.

The results indicate that the process of polishing considerably improved the effluent quality of the system. Biochar performed best in removing organic matter, total N, turbidity and odor. Filtralite was superior in removing P. The contribution of the polishing step in removing total coliform bacteria (TCB) and Escherichia coli (E. coli) was remarkable. Additional log reduction of 2.18, 2.26 and 1.81 for TCB and 2.26, 2.70 and 2.01 for E. coli was obtained compared to the GWTP due to biochar, filtralite and control column, respectively.

This study demonstrates the opportunities for improving the performance of decentralized greywater treatment systems by integrating locally available polishing materials to achieve a better quality effluent.

The present study identifies efficient polishing system for decentralized and compacted greywater treatment system. The recommended polishing materials potentially improve the quality of effluents and add social, economic and environmental values.

A sensor to determine TOC is described. It is based on the photoassisted degradation of organic compounds concurring to TOC and on the determination of the resultant CO₂. The sensor was successfully tested on target molecules, demonstrating that the linear correlation constant between TOC values and produced CO₂ varies according to the considered compound so that absolute value determination is not possible in largely heterogeneous solutions but can only be referred to reference compounds on the TOC scale.