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1.
Changing the concepts of economic development and introducing new amendments can hardly decrease the accumulation in the soil of such pollutants as metals, remaining there for a long time. The predictive models for describing the balance of metals in the soil, which are based on the ‘atmosphere–plant–soil’ system and reflect the complicated physical–chemical nature of the metals’ migration, expressed by coefficients obtained in long-term observations in natural conditions, allow for evaluating long-term concentration of metals in the soil. The model BALANS evaluates self-purification of soil, taking into account the uptake of metals of aerogenic origin by the soil together with amendments, their physical–chemical migration and the type of microrelief determining its intensity as well as the absorbed biomass of plants and the removal of metals with crops. In this model, the half-period of metals’ washing out from the soil, found for the microrelief characteristic of low places, exceeds 200 years for Ni, Cr and Pb and makes 90 and 150 years for Zn and Cu, respectively.  相似文献   
2.
Foods and feeds were analyzed during the period of 2007–2014 employing validated and accredited methods based on gas chromatography–high-resolution mass spectrometry. Sampling has been carried out in-line with national monitoring programs as well as during import controls into Lithuania. Food samples such as eggs, milk, beef, pork, poultry, fats of plant and animal origin, fish, cod liver, and feed samples such as premixes, feeds of plant origin, compound feed, mineral feed, vegetable oil, and fish meals were analyzed. Most of the samples exhibited concentrations below maximum limits, except cod liver. Health impacts were assessed in respect to human daily intakes. Data between groups are compared.  相似文献   
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A total of 22 bottom surface sediment samples were collected from Klaip?da Harbour, Lithuania (Baltic Sea). Sediment parameters, such as grain size and concentrations of total organic carbon, aliphatic hydrocarbons (ALHs) and polycyclic aromatic hydrocarbons (PAHs), were determined. Hydrocarbon contamination levels in the sediments were estimated based on classifications provided in the literature, and potential biological effects were assessed based on the effects range low–effects range median values of the Sediment Quality Guidelines and on the total toxic benzo(a)pyrene equivalent. The results demonstrated that concentrations of PAHs and total aliphatic hydrocarbons in the sediments varied between 1.6 and 5456?ng?g?1 d.w. and 6.9 and 727?μg?g?1 d.w., respectively. In most cases, the concentrations of ALHs and PAHs in the sediments indicated low to moderate levels of pollution and were not observed to have any significant adverse effects on living biota. To determine possible sources of hydrocarbons, hydrocarbon compositions were analysed, and ALHs’ and PAHs’ specific diagnostic ratios were calculated. According to the results, the Klaip?da Harbour bottom sediments were dominated by PAHs of pyrogenic origin, whereas the origin of ALHs was mixed, that is, anthropogenic with a biogenic (aquatic and terrestrial) input.  相似文献   
5.
Among chemical industries, petroleum refineries have been identified as large emitters of a wide variety of pollutants. Benzene, toluene, ethylbenzene, and xylene (BTEX) form an important group of aromatic volatile organic compounds (VOCs) because of their role in the troposphere chemistry and the risk posed to human health. A very large crude oil refinery of the Baltic States (200,000 bbl/day) is situated in the northern, rural part of Lithuania, 10 km from the town of Ma?eikiai (Lithuania). The objectives of this study were: (1) to determine of atmospheric levels of BTEX in the region rural and urban parts at the vicinity of the crude oil refinery; and (2) to investigate the effect of meteorological parameters (wind speed, wind direction, temperature, pressure, humidity) on the concentrations measured. The averaged concentration of benzene varied from 2.12 ppbv in the rural areas to 2.75 ppbv in the urban areas where the traffic was determined to be a dominant source of BTEX emissions. Our study showed that concentration of benzene, as strictly regulated air pollutant by EU Directive 2008/50/EC, did not exceed the limit of 5 ppbv in the region in the vicinity of the crude oil refinery during the investigated period. No significant change in air quality in the vicinity of the oil refinery was discovered, however, an impact of the industry on the background air quality was detected. The T/B ratio (0.50-0.81) that was much lower than 2.0, identified other sources of pollution than traffic.  相似文献   
6.
Environmental Modeling & Assessment - Lucas–Washburn equation is a fundamental expression which is used to describe capillary rise in porous materials according to average pore radius,...  相似文献   
7.
The varied and very dynamic landscape with a high biological diversity is a distinctive feature of the Curonian spit at the regional scale. Throughout the 20th century the main morphodynamic trend in the littoral of the Curonian spit was shoreline grading on the lagoon side, whereas on the marine side the increasing erosion at the foot of the spit, and increasing accretion at the head of the spit prevailed. The results of a discriminant analysis (Wilkes’ λ = 0.001626 and F = 29.267 when p < 0.001) show that sites with prevailing erosion, accretion and sediment input from the drifting dunes form regular inter-related spatial structures in the littoral with distinctive resulting discontinuities of the sediment drift along the lagoon coast. Dune littoral cells are characterized by Aeolian sediment input and distribution ‘down-drift’, (usually northwards) from the source. The most likely changes in the current development trends of the lagoon shore zone of the Curonian spit are related to expected climate changes and further slowing down of the dune drift. The probability of storms and ice-drift events, and their impact on coasts is expected to increase as a result of climate change. The dune advance will gradually slow down, and with it, the sand input to the coastal zone will decline. In this paper, we define integrated shoreline management as a system of long-term shoreline management measures, which is based on a littoral cell approach and aimed at harmonizing human activity in the coastal zone with the natural development of the shoreline. We propose an integrated management program for the lagoon shoreline of the Curonian spit, which is site-specific for each littoral cell as a coastal management unit. Drifting dunes and seaside beaches are the natural amenities, which are best known and best appreciated on the Curonian spit by 49% of the respondents representing the total Lithuanian population. A responsible tourism development should be considered as the key means for proper appreciation of the drifting dunes and natural coasts by society, which means to acknowledge and cherish the aesthetic and conservation values of dune and coastal landscapes of the Curonian spit as a World Heritage Site. There are at least two pre-conditions for this: (1) to provide visitors with sufficient information about diverse values and functions of the Curonian dunes and coasts within a broader regional and global heritage conservation context; (2) to enable tourists to enjoy the most impressive dune and coastal landscapes at close range. In this paper we propose to encourage active dune tourism, to reintroduce grazing into the Curonian dune areas, to restore and to preserve the most impressive landscapes of the highest white drifting dunes by bringing the blown out sand from the leeward foot of the dunes back to the crest artificially.  相似文献   
8.
Cyanides are very popular electrolytes used in metal electroplating, metal ore processing, chemical and electrochemical applications. Due to wide utility of these technologies cyanides become increasingly harmful effluent, which has to be treated. One of the best ways to degrade cyanides is an anodic electrooxidation. In this work the destruction of free cyanide on platinum, titanium and stainless steel (SS) electrodes has been investigated. It was determined that anode material greatly influences the process of cyanide electrooxidation. The best results were obtained by using the Pt electrode. This kind of anode allows us to reduce CN? concentration from 0.1 M to 0.06 M during the first hour of electrolysis at a current density of 200 A m?2, with a current efficiency up to 80%. To substitute expensive Pt anodes Ti electrodes covered with nanolayers of Pt were prepared and used for the anodic oxidation of cyanide ions. An effect of a thickness of Pt layer and temperature of an electrolyte solution were studied. It was established that using platinized Ti electrodes the current efficiencies of electrooxidation of cyanides of about 60% can be obtained. The usage of chloride ions to facilitate the destruction of cyanide was also studied.  相似文献   
9.
Living or formerly living organisms are being used to obtain information on the quality of the general health status of our environment by bioindication and biomonitoring methods for many decades. Thus, different roads toward this common scientific goal were developed by a lot of different international research groups. Global cooperation in between various scientific teams throughout the world has produced common ideas, scientific definitions, and highly innovative results of this extremely attractive working field. The transdisciplinary approach of different and multifaceted scientific areas—starting from biology, analytical chemistry, via health physics, up to social and economic issues—have surpassed mental barriers of individual scientists, so that “production” of straightforward common results related to the influence of material and immaterial environmental factors to the well-being of organisms and human life has now reached the forefront of international thinking. For the further sustainable development of our common scientific “hobby” of bioindication and biomonitoring, highest personal energy has to be given by us, being teachers to our students and to convince strategically decision makers as politicians to invest (financially) into the development of education and research of this innovative technique. Young people have to be intensively convinced on the “meaning” of our scientific doing, e.g., by extended forms of education. One example of multilingual education of students on a global scale and perspective is given here, which we started about 3 years ago.  相似文献   
10.
Environment, Development and Sustainability - The changes in pro-environmental behaviour, whether people become more environmentally friendly or not, have been analysed very scarcely. Therefore,...  相似文献   
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