Assessing trace metal contamination and organic matter in the brackish lakes as the major source of potable water

Environmental Geochemistry and Health - On small and medium karstic coastal islands in the Adriatic Sea, brackish lakes are often the only source of freshwater. Therefore, it is important to...     

An analysis of wind conditions at pedestrian level in the selected types of multi-family housing developments

Environmental Fluid Mechanics - The following article addresses the issue of wind conditions around urban building development at pedestrian level. Factors that depend on those issues include wind...     

Conversion of specialised dairy farming systems into sustainable mixed farming systems in Cuba

From the 1960s onwards, a ‘High External Input’ dairy production model was applied widely in Cuba. Overall milk production of the national herd increased considerably, but the system was inefficient from both a financial and energetic point of view. In the early 1990s, after the abrupt end of inflow of capital and other resources from Eastern Europe, the dairy sector collapsed. In the short term, the modern infrastructure of milk production deteriorated and the sector experienced profound vulnerability. However, in the longer term, this situation stimulated a search for more sustainable approaches, such as low external input Mixed Farming Systems (MFS). The current study aimed to evaluate two small scale prototype farms to assess the implications of converting ‘Low External Input’ Dairy Farming Systems into MFS. Fifteen agro-ecological and financial indicators were selected and monitored over a 6-year period. Two configurations of MFS, i.e. the proportion of the farm area occupied by arable crops, were tested: 25 and 50%. Productivity, energy efficiency and cost-effectiveness all improved following conversion. Total energy input was low for both farms and decreased over time, whereas energy efficiency was high and increased over time. Human labour input was high directly following conversion, but decreased by one-third over the 6-year period. This study demonstrates, at an experimental scale, the potential of MFS to achieve ecological, productivity and financial advantages for dairy production in Cuba. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

Dynamics of potassium leaching on a hillslope grassland soil

There have been only a few studies of potassium (K) losses from grassland systems, and little is known about their dynamics, especially in relation to nitrogen (N) management. A study was performed during the autumn and winter of 1999 and 2000 to understand the effects of N and drainage on the dynamics of K leaching on a hillslope grassland soil in southwestern England. Two N application rates were studied (0 and 280 kg N ha(-1) yr(-1)), both with and without tile drainage. Treatments receiving N also received farmyard manure (FM). Higher total K losses and K concentrations in the leachates were found in the N + FM treatments (150 and 185% higher than in 0 N treatments), which were related to K additions in the FM. Drainage reduced K losses by 35% because of an increase in dry matter production and a reduction in overland and preferential flow. The pattern of change in K concentration in the leachates was associated with preferential flow at the beginning of the drainage season and with matrix flow later in winter, and was best described by a double exponential curve. Rainfall intensity and the autumn application of FM were the main determinants of K losses by leaching. The study provided new insights into the relationships between soil hydrology, rainfall, and K leaching and its implications for grassland systems.     

234U and 238U isotopes in water and sediments of the southern Baltic

The aim of this work was to determine the concentration of 234U and 238U and calculate the values of the 234U/238U activity ratio in waters and sediments from the various regions of the southern Baltic Sea: Gdańsk Deep, S?upsk Narrow and Bornholm Deep. The concentration of uranium in analysed sediments from southern Baltic increase with core depth to what probably is connected with diffusion from sediments to water through interstitial water, where uranium concentration is much higher than in bottom water. The highest concentrations of uranium were observed in sediments of S?upsk Narrow (0.66-7.11 mg kg(-1) d.w.) and S?upsk Bank (0.61-6.93 mg kg(-1) d.w.), the lowest in sediments from Bornholm Deep (0.54-3.77 mg kg(-1) d.w.). The 234U/238U activity ratio results indicated that the sedimentation of terrigenic material and Vistula River transport are the general sources of uranium in the southern Baltic sediments. The value of 234U/238U activity ratio in sediments from reduction areas from southern Baltic (Gdańsk Deep and Bornholm Deep) indicated that reduction process of U(VI) to U(IV) and removing of anthropogenic uranium from seawater to sediments constitutes a small part only in Gdańsk Deep.     

Framework for the uncertainty assessment in the impact pathway analysis with an application on a local scale in Spain

The estimation of damage estimates due to air emissions gives important basic knowledge for decision-making on the level of environmental politics and business strategies. Nowadays, a frequently applied method to estimate environmental damages is the Impact Pathway Analysis (IPA), which can be easily carried out using models such as EcoSense or PathWays. These models produce results in a relatively short term. However, there is a lack of reliability in the results. As in many other environmental software tools, the uncertainty is the key problem that makes it difficult to convince decision-makers by the outcomes of a study. Therefore, a framework that allows assessing the uncertainties within studies in which the IPA is applied on a local scale has been developed. In this assessment framework, the uncertainties of the used parameters, including their spatial and temporal variability, are taken into account. As the model is processing a huge quantity of data, one step of the assessment consists of a screening procedure to determine the parameters that are supposed to be fixed. For the other data, probability distributions have to be selected and classified into two groups: extensively available data for which average and standard deviation can be calculated and data based on little information. A quantification of the uncertainty can be completed by a stochastic model in the form of Monte Carlo (MC) simulation on the basis of the framework. As an illustration of the framework, we have applied it to a study on the installation of an advanced gas treatment in the municipal waste incinerator of Tarragona. It can be shown that the presented stochastic approach gives a lower geometric deviation than the analytical one and that the new gas treatment reduces the environmental damages without any doubt.     

Study of 222Rn concentrations in drinking water in the north-eastern hydroregions of Poland

This paper presents the results of radon concentration measurements in the drinking water from the municipal water supply system and private wells located in the north-eastern part of Poland. The measurements were carried out on 643 samples using a liquid scintillation method. The mean value was found to be 5262 Bq m-3 with a maximum of 38347 Bq m-3. The samples were obtained from different water-bearing levels, i.e. surface water, deep borehole water and well water and have respective mean values of 3398, 5178 and 6155 Bq m-3. In 57 water samples, a guideline maximum level of 11,000 Bq m-3 was found to be exceeded. The observed radon concentration in water can contribute to a 2% increase in indoor radon concentration.     

Metals distribution and interactions in tissues of shrews (Sorex spp.) from copper- and zinc-contaminated areas in Poland

To assess the risk from heavy metal accumulation to insectivorous species exposed to different pollutants, shrews [Sorex araneus (Linnaeus 1758) and Sorex minutus (Linnaeus 1766)] were collected in the Olkuski Ore Region (OOR; a Zn and Cd smelter area), Legnicko-G?ogowski Copper Mine Region (LGCR; a copper ore-mining area), and Bia?owieza Forest (BF; a control area). A few sites were chosen in each region and a total of 57 animals were collected from them. The liver and kidneys were dissected from the animals, dried, and digested in a 4:1 mixture of HNO3 (nitric acid) and HClO4 (perchloric acid). Cadmium, lead, zinc, copper, and iron were determined in the samples by flame or flameless atomic absorption spectrometry. The interactions between toxic and essential metals were calculated for each tissue. The data showed that accumulation of metals by insectivores is high; shrews accumulated much higher amounts of cadmium and lead than bank voles, studied by other researchers, from the same areas. The expected high tissue accumulation of copper at LGCR and zinc at OOR was not seen, but the levels of both elements were higher in the tissues of shrews from OOR than from LGCR. The lowest copper concentrations were in the tissues of shrews from BF. The highest cadmium and lead concentrations were found in the tissues of shrews from OOR. Some significant correlations were found between the tissue concentrations of xenobiotic and essential metals (e.g., between cadmium and zinc and between lead and iron).     

An assessment of the toxicity of pyridinium chlorides and their biodegradation intermediates

Toxicity investigations were conducted for four pyridinium chlorides belonging to cationic surface-active substances (CSAS), which differed from each other in the numbers of methyl groups (CH(3)) in pyridinium ring.The crustacean Daphnia magna, the fish Lebistes reticulatus and the alga Scenedesmus quadricauda were chosen as biotests. Toxicity of examined preparations appeared to be very high but did not depend on their chemical structure. S. quadricauda was the most sensitive organism. Toxicity of intermediate products obtained in biological oxidation process was also examined. Biodegradation was conducted according to the "river water test". It was found that only partial degradation took place while pyridinium chlorides constituted main energy and carbon source. Presence of biodegradation intermediate products was shown on the basis of 1H NMR analysis. Intermediates were not toxic to any biotests.     

Cost-benefit analysis as a tool for decision making in environmental projects

BACKGROUND, AIM AND SCOPE: The Damage-Function method is an efficient tool recently used in decision-making processes concerning environmental management. It is based on finding the relation between the origin of an environmental charge, and its impact on human health and the environment. The aim of the present investigation was to assess the positive impacts, also called benefits, of changes in environmental quality, and the economic viability of an industrial project on reduction of PCDD/F emissions. It has been developed with monetary criteria of two worldwide ambits: USA and European-Union countries. METHODS: The current study is a continuation of a previous investigation in which Substance Flow Analysis and Control Analysis Techniques were used to identify and to analyze all main flow values of PCDD/Fs inside the system of Tarragona Province (Spain). In the present study, Cost-Benefit Analysis (CBA) has been employed. The benefits derived from a minimization in the incidence of cancer due to a reduction in the emission of PCDD/Fs have been evaluated considering the value of a statistically saved life (VSL). Statistical analysis about uncertainty has also been incorporated. Here, the Monte Carlo simulation technique has been used. RESULTS: It is shown that CBS results depend firstly on the kind of VSL used. In fact, the differences between the decisions as a result of applying monetary criteria in USA and EU can be explained by differences between VSL values. CONCLUSION AND RECOMMENDATION: It is concluded that, for prices estimated in Euros, the emission cleaning project in the industrial plant is not feasible under any circumstance. However, although CBA seems to be a good analytical method, the final decision corresponds to the managers, who must weigh up not only the monetary criteria, but factors such as social questions.