Factors influencing fatty acid and hydrocarbon composition of sedimenting particles in the northeastern Adriatic Sea

Fatty acids and hydrocarbons of sedimenting particles were investigated in the northeastern Adriatic Sea from November 1988 to December 1989. Particles were collected at approximately monthly intervals, using sediment traps deployed at 30 m depth (2 m above bottom). Seasonal changes in sedimentation of particulate matter were very pronounced. Hydrocarbon fluxes and concentrations were found to vary significantly depending on the season. They averaged 2.69 ± 1.44 mg m⁻² day⁻¹ and 232.4 ± 90.93 μg g⁻¹ in winter, respectively. In late spring-early summer the corresponding values amounted to 0.045 ± 0.015 mg m⁻² day⁻¹ and 13.72 ± 5.56 μg g⁻¹, and they increased towards autumn, when mean values of 0.517 ± 0.228 mg m⁻² day⁻¹ and 98.86 ± 48.72 μg g⁻¹ were obtained. In contrast, fatty acid fluxes and concentrations were low during winter (0.26 ± 0.08 mg m⁻² day⁻¹ and 21.95 ± 3.35 μg g⁻¹), increased slightly towards the summer (0.48 ± 0.12 mg m⁻² day⁻¹ and 139.9 ± 44.6 μ g⁻¹) and reached maximum rate and concentration in autumn, when average values were 1.98 ± 1.30 mg m² day⁻¹ and 489.1 ± 186.7 μg g⁻¹, respectively. The differences in composition, concentrations and fluxes of the fatty acids and hydrocarbons were related to the sources of sedimenting material, reflecting the influence of resuspension of bottom sediments during winter and the appearance of mucus aggregates during summer and their subsequent deposition in autumn.     

Suitability of linden and elder in the assessment of environmental pollution of Brestovac spa and Bor lake (Serbia)

The suitability of linden and elder as biomonitors was evaluated in the tourist zone of the Bor region well known for pyrometallurgical copper production. The concentrations of As, Cu, Pb and Zn in the soil, washed and unwashed leaves and roots of linden and elder were determined. The absorption of As, Cu, Pb and Zn from soil to roots and leaves, as well as the translocation of the studied elements from roots to leaves, was analysed. It was observed that the soil in the tourist zone of Bor (Bor lake and Brestovac spa) was greatly polluted with Cu and As. Linden and elder leaves can be used as a low-cost material for detection of As, Cu, Pb and Zn in the atmospheric deposition, which was concluded due to the amounts of these elements removed after a washing treatment. Thus, canopies of linden and elder might have an important role in the removal of the polluting substances from the air. The elder leaves were more suitable to be used for indication of environmental pollution with As, Cu and Pb than the linden leaves. The area of the Bor lake sampling site had higher air pollution with As and Pb than Brestovac spa, since greater amounts of As and Pb were washed off the linden and elder leaves from the Bor lake sampling site. The linden and elder used different adaptation strategies in conditions of the increased soil and air pollution. These strategies were based on different efficiencies of element absorption from the soil and on limited or efficient translocation of the studied elements from roots to leaves, and therefore, they have an important role in the biogeochemical cycling of the examined elements in the environment.     

Comprehensive Biogeochemical Analysis of Nitrogen Transformation Parameters

Water Resources - The potential for nitrogen attenuation in anoxic groundwater by examining the concentration and distribution patterns of electron acceptors, electron donors and microbiological...     

Understanding the influence of climate elements on traffic: the wind impact approach

Theoretical and Applied Climatology - Due to intense highway congestion in Europe, increased percentage of highway accidents, as well as mortality rate, safety is an imperative in highway planning...     

Land use optimization for sustainable development of mountain regions of western Serbia

This study analyses the possibilities for optimal land use structure in mountainous areas of rural Serbia, which is faced with problems such as unfavorable terrain characteristics and inadequate land use patterns causing economic underdevelopment and increasing population migration. In the case of a small privately owned farm in Western Serbia, optimal land use pattern is determined using the linear programming model. The objective function-cost-effectiveness or soil erosion reduction, as well as constraints, are formulated using the benefit-cost ratio (BCR) for a 15-year production period and soil losses data calculated using the Universal Soil Loss Equation (USLE). The best results are achieved using the scenario with the aim to minimize soil erosion, considering the BCR in the constraints. This scenario is proposed since it was registered that the benefit for landowners would increase by five times, while the losses of land would decline about 80%. The sensitivity analysis of investments is performed to check whether the price variation affects the cost-effectiveness of proposed land use. Results show that market changes (nine cases are considered) do not lead to significant changes in land use allocation. Proposed land use pattern improves the environmental condition, strengthens the rural economy and thus offers the greatest potential for sustainable development of mountainous rural areas.     

Direct Formation of Burkeite in the Geothermal Waters at Vranjska Banja,Serbia

Natural Resources Research - There are no available data about direct burkeite formation on the geothermal waters pipelines in Europe. Data about accompanying minerals of burkeite are also scarce....     

Observations on the desmositic and spilositic rocks in the Dinarides

The Jurassic volcano-sedimentary formation of the Dinarides is build up of diabases, spilites, cherts, argillaceous sediments, desmositic and spilositic rocks. Tuffs, however, are rare.The desmositic and associated spilositic rocks encircle volcanics, and build up zones several km wide and up to one km thick. Their characteristic mineral assemblege is albite-chloriteepidote-calcite, sericite and quartz. Farther away from the diabases/spilites the desmosites contain more frequent relicts of shales, and finally pass into shales. The desmositic rocks are characterized by structures formed by turbulent movements of unconsolidated mud.The desmositic and spilositic rocks were formed under the influence of injections of basic lavas in unconsilidated mud. The magmatic Na-rich hydrothermal solutions and the heated water from mud produced a recrystallization of the sediments and formation of albite.     

Incorporating spatial and temporal information for urban drainage model calibration: An approach using preference ordering genetic algorithm

In order to successfully calibrate an urban drainage model, multiple criteria should be considered, which raises the issue of adopting a method for comparing different parameter sets according to a set of objectives. Multi-objective genetic algorithms (MOGA) have proved effective in numerous such applications, where most of the techniques relying on the condition of Pareto efficiency to compare different solutions. However, as the number of criteria increases, the ratio of Pareto optimal to feasible solutions increases as well, worsening the efficiency of the genetic algorithm search. In this paper, firstly the drawbacks of single objective calibration approach are highlighted. Then, a new MOGA, the preference ordering genetic algorithm, is proposed, that alleviates the drawbacks of conventional Pareto-based methods. The efficacy of this algorithm is demonstrated on the calibration of a physically-based, distributed sewer network model, and the comparison is made with a known MOGA NSGA-II. The results are very encouraging because the obtained parameter sets closely resembled both calibration and validation events. The identifiability of 10 model parameters were analysed, showing significantly smaller ranges of optimal values for parameters related to impervious areas compared to those related to pervious areas, which is reasonable considering relatively low rainfall intensities. In addition to standard ways of presenting calibration results, “radar” plots were also used to present information on trade-off for eight objective functions for four rainfall-runoff events.     

Distribution and fate of metals in the Montenegrin part of Lake Skadar

Skadar Lake,the largest lake on the Balkan Peninsula,is famous for a wide range of endemic and rare,or even endangered plant and animal species.Different anthropogenic pressures have,however,influenced the fragile equilibria of the lake ecosystem,with metal pollution as one of the primary concerns.Therefore,this study investigated spatial distribution of metal pollutants in the water and sediment phase of Skadar Lake,and anthropogenic and environmental factors affecting this distribution.A sieving analysis showed that sediment in Skadar Lake is mainly distributed in the three smallest fractions（colloid,clay and silt）.Eleven metals were analyzed in the lake surface and bottom water,and only six of them were detected：potassium,magnesium,calcium,nickel,aluminum and manganese.They were all present at low concentrations.In contrast,sediments contained elevated levels of some metals with concentrations between 28.1-126.8 mg kg~（-1） for Ni,23.6-79.2 mg kg~（-1） for Cr,9.2-36.9 mg kg~（-1） for Cu,199-878 mg kg~（-1） for Mn and 9.6-23.1 g kg~（-1） for Fe.Nickel exceeded consensus-based guidelines for safety towards freshwater dwelling organisms.The organic matter content of the sediment fluctuated between 4.7 and 21.5%.No correlations were found between metal concentrations,organic matter and sediment particle size fractions,suggesting that the latter are not the main factors controlling metal accumulation in Skadar Lake.     

The statistical characters of PM10 in Belgrade area

The concentrations of air pollutants depend on meteorological conditions and pollutant emission level. From the statistical properties of air pollutants the number of times the daily average concentrations exceed the assigned air quality standard (AQS) can be estimated, as well as the level of reduction of particle matter emission sources required to meet the AQS. In this paper three statistical distributions (lognormal, Weibull and type V Pearson distribution) were used to fit the complete set of PM₁₀ data for the Belgrade urban area during a three-year period (2003–2005). The method of moments and the method of least squares were both used to estimate the parameters of the three theoretical distributions. The type V Pearson distribution represented the PM₁₀ daily average concentration most closely. However, the parent distributions sometimes diverged in predicting a high PM₁₀ concentration and therefore asymptotic distributions of extreme values were used to fit the high PM₁₀ concentration distribution more correctly. This method can successfully predict the return period and exceedances over a critical concentration in succeeding years. The estimated emission source reduction of PM₁₀ to meet the assigned standard varied from 53% to 63% in the Belgrade urban area. The results provide useful information for air quality management and could be used to examine the similarities and differences among air pollution types in diverse areas.