Connectivity approach in urban protected area management based on soil and vegetation chemical status.

The quality and vitality of cities largely depend on the design, management, and maintenance of green areas, including urban protected areas (UPAs), since they provide multiple benefits for the city. Due to urbanization and higher anthropogenic pressure, green areas are decreasing which directly affects natural habitats and biodiversity. This study aims to assess soil and vegetation chemical status in UPAs in the city of Belgrade, Serbia, and to understand how their distance from pollution hotspots affects soil and vegetation quality. Additionally, this paper considers the inclusion of soil and vegetation conditions in the urban protected areas management as a basis for introducing a connectivity approach to expand green infrastructure throughout the city. Chemical properties, the content of nutrients (C, N, P, and K), and microelements (Cr, Co, Ni, Cu, Zn, As, Cd, Sn, Pb, Zr, U, and Th) in soil and conifer needles were analyzed. Results showed that the distance of pollution hotspots does not affect nutrient and microelements concentrations in soil, i.e., they do not vary significantly between sites and do not exceed remediation intervention values. However, the microelements status of vegetation is affected since Cr, Cu, Zn, Sn, and Pb are higher in needles from trees from the city center. The state of soil and plant composition supports the establishment of a network of green corridors and should become a part of management strategies, thus helping biodiversity protection, climate change mitigation, and human well-being in the cities.

Prediction of the Impact of Land Use and Soil Type on Concentrations of Heavy Metals and Phthalates in Soil Based on Model Simulation.

The main objective of this study is to determine the possibility of predicting the impact of land use and soil type on concentrations of heavy metals (HMs) and phthalates (PAEs) in soil based on an artificial neural network model (ANN). Qualitative analysis of HMs was performed with inductively coupled plasma-optical emission spectrometry (ICP/OES) and Direct Mercury Analyzer. Determination of PAEs was performed with gas chromatography (GC) coupled with a single quadrupole mass spectrometry (MS). An ANN, based on the Broyden-Fletcher-Goldfarb-Shanno (BFGS) iterative algorithm, for the prediction of HM and PAE concentrations, based on land use and soil type parameters, showed good prediction capabilities (the coefficient of determination (r2) values during the training cycle for HM concentration variables were 0.895, 0.927, 0.885, 0.813, 0.883, 0.917, 0.931, and 0.883, respectively, and for PAEs, the concentration variables were 0.950, 0.974, 0.958, 0.974, and 0.943, respectively). The results of this study indicate that HM and PAE concentrations, based on land use and soil type, can be predicted using ANN.

Green Infrastructure Designed through Nature-Based Solutions for Sustainable Urban Development.

With the goal of enhancing the quality of the environment, urban green infrastructure (UGI) is an essential element in sustainable cities, and nature-based solutions (NBS) are being carried out as new infrastructure solutions that increase the resilience of cities. In this research, the method of theoretical analysis and the content analysis as the basic fact-gathering technique was applied to answer to following questions: What are the hindrances and bottlenecks in implementing NBS? Are the current decision-making mechanisms helping NBS get in route to shape cities? Is there any binding policy in practice that promotes NBS? In Belgrade is planned Type 3 of the degree of intervention/level and engineering type-Creation and new ecosystem management in the classifications of intensive urban green space management; urban planning strategies; urban water management; ecological restoration of degraded terrestrial ecosystems; and restoration and creation of semi-natural water bodies and hydrographic networks. In the future, it is essential to implement policies and incentives on national, regional, and local scales that help encourage the usage of NBS in the development of urban infrastructure.

Spatial distribution and source identification of heavy metals in European mountain beech forests soils.

The main objectives of this research were to (i) investigate the concentration; (ii) characterize the distribution; (iii) determine the sources apportionment; (iv) estimate environmental and health risks of heavy metals in soil from mountain beech forest. A total of 76 soil samples from 20 pure beech forest stands from Bosnia and Herzegovina (BA), Bulgaria (BG), Check Republic (CZ), Germany (DE), Italy (IT), Poland (PL), Romania (RO), Serbia (RS), Slovakia (SK), Slovenia (SL), and Spain (ES) were collected. The content of major elements was measured by X-ray fluorescence spectroscopy (XRF). The content of heavy metals was measured by inductively coupled plasma-optical emission spectrometry (ICP/OES). Heavy metals had a specific concentration range, which followed in soil samples from depth 0-40 cm the common order (low to high): Hg < Cd < As < Co < Pb < Ni < Cu < Cr < Zn, and from depth 40-80 cm: Hg < Cd < As < Pb < Co < Ni < Cu < Cr < Zn. The grouping of the examined parameters according to rock types, soil types, and localities indicated the separation of carbonate rocks from other substrates, luvisol, and rendzina from other soil types, and samples from BA, SL, and IT from other localities. According to sources apportionment As, Pb and Zn are of anthropogenic origin, Cd, Co, Cr, and Ni are of geogenic origin, while the middle position of Cu and Hg indicates a combined contribution of both sources. Elements Cd and Hg indicated severe to extremely severe enrichment with a mean value of 24.3 and 70.6, respectively. Based on the determined values Ni, Cr, As and Cd do not pose a health risk.

Geochronological investigation of the Danube Djerdap Lake sediments (Serbia): sedimentology and inorganic composition.

The objective of this study is geochronological investigation of sedimentological and inorganic composition, in the Danube Djerdap Lake sediments in order to obtain reliable information about former pollution. Eleven samples were taken from the 135-cm-deep sediment core drilled at the Orlova location. Since the core represents sediments deposited during 1972-2016, the sedimentation rate of ~ 3 cm year-1 was estimated. Grain size, mineralogical and geochemical composition was determined. Sediments are sandy silts and clayey silts, and only the deepest and shallowest layers contain > 30% of sand-size fraction. The highest concentrations of minor elements are found in the oldest sediment (1972-1977) as a consequence of the high flux of the material from variable sources. During the sedimentation period (1975-1990), the concentrations of analyzed elements are generally decreasing until the beginning of 1990s. After this period, there are two distinct decreases and two distinct increases in concentrations of elements. The fluctuations in minor element concentrations are a consequence of both natural and anthropogenic sources. Granitic rocks situated south are source of minerals that carry minor elements. Enrichment Factor, Geoaccumulation Index, Contamination Factor and Pollution Load Index indicate that concentrations of certain minor elements at specific depositional periods have anthropogenic source.

Is Kragujevac city still a "hot spot" area, twenty years after the bombing?

After NATO bombing of Serbia in 1999, UNEP has identified Kragujevac as one of the four heavily polluted environmental "hot spots". Damaging of industrial and military targets caused the release of substantial amounts of hazardous chemical substances into the environment. This study was conducted in order to access the exposure of residents of Kragujevac city to persistent soil pollutants, twenty years after NATO air campaign. The paper reports the results of measuring radionuclides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and heavy metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn, and Hg) in soil samples collected from two depths (0-15 cm and 15-30 cm) at 30 locations along the riverbank of the Lepenica River. The average specific activities of 226Ra, 232Th, 40K and 137Cs were comparable to average worldwide values; excess lifetime cancer risk (ELCR) from natural radionuclides ranged from 1.1·10-4 to 3.3·10-4. The measured concentrations of As, Co, Cr, Cu, and Ni exceeded the limit values in most of the samples. Non-carcinogenic risk (hazard quotient and hazard index) and carcinogenic risk from heavy metals were assessed. Total hazard index was 0.257 and 2.16 for adults and children, respectively. Sum of measured PAHs ranged from 110 to 1026 µg kg-1. Sum of PCBs exceeded the limit value of 20 µg kg-1 in all samples (it ranged from 48.8 to 196.8 µg kg-1), but it was still below the remediation level. The differences between two layers with respect to all measured variables were not statistically significant.

Future environmental challenges of the urban protected area Great War Island (Belgrade, Serbia) based on valuation of the pollution status and ecosystem services.

The Great War Island (GWI) is an area of importance for the protection of the environment, cultural and historical heritage of Belgrade, Serbia. According to the International Union for Conservation of Nature (IUCN) this area belongs to the IV category - Habitats and Other Regulated Areas. The main objectives of this paper are to evaluate the potential impacts of pollution on ecosystem services of the Great War Island and to explore different scenarios for future urban development of the Great War Island that will have implication for human well-being. The aims of this paper are set up based on the evaluation of ecosystem services of the Great War Island and assessment of the pollution status of the Great War Island. In order to evaluate pollution status of the GWI inorganic and organic composition of sediments were examined. Additionally, the content of microelements was determined in the leaves of the Salix alba L. Pollution indices indicate that all investigated sampling sites are polluted and correspond to high and very high degree of contamination. Cd and Cu show high to extremely high degree of contamination while Sb has extremely high degree of contamination. Content of As, Co, Cu, Ni and Zn in leaves of Salix alba L. is in sufficient to normal range, while content of Cd is between the sufficient and excessive values generalized for various species. Typical oil distributions of terpanes and steranes and values of the corresponding maturity parameters clearly indicated that the sediments of the GWI, in addition to native organic matter, contained oil pollutants of anthropogenic origin. GWI provides provisioning, regulating, supporting and cultural ecosystem services. In relation to ecosystem services two possible scenarios can be predicted: first - losing the status of a protected area due to urbanization; and the second - increasing the degree of protection by admission into international protection lists.

Evaluation of heavy metals and radionuclides in fish and seafood products.

Despite the existence of a legislation regarding food contaminants, food safety control in Serbia is a matter of great concern. This study investigates the radioactivity levels and heavy metal concentrations in fish and seafood commercially available in Serbian markets. Domestic fish species (caught in the Danube River) and fishery products imported from Europe, Asia and America were analyzed. The content of natural radionuclides and 137Cs were investigated by gamma spectrometry. Activity concentration of 40 K was measured in the range of 44-165 Bq kg-1; low levels of 137Cs were detected in two samples (2.8 and 3.0 Bq kg-1), while concentrations of 226Ra and 232Th were below minimal detectable values. Concentrations of heavy metals (Cd, Hg and Pb) were determined using ICP-OES method. Cd concentration ranged from 0.01 to 0.81 mg kg-1 in sea fish and from 0.01 to 0.03 mg kg-1 in freshwater fish. Hg concentrations were in the range of 0.01-1.47 mg kg-1; the highest value was measured in the predator fish - shark. The highest level of Pb (6.56 mg kg-1) was detected in a blue sea fish (Atlantic mackerel). The health risks associated with the intake of heavy metals and radionuclides via fish consumption were evaluated. The results indicate that fish and seafood consumption do not pose a significant health concern in the case of the usual consumption rate which is typical for the population of Serbia. However, a highly frequent consumption of fishery products can have adverse health effects, especially due to Hg and Pb contamination.

Importance of background values in assessing the impact of heavy metals in river ecosystems: case study of Tisza River, Serbia.

The main objective of this paper is to evaluate how a choice of different background values may affect assessing the anthropogenic heavy metal pollution in sediments from Tisza River (Serbia). The second objective of this paper is to underline significance of using geochemical background values when establishing quality criteria for sediment. Enrichment factor (EF), geoaccumulation index (I geo), pollution load index (PLI), and potential ecological risk index (PERI) were calculated using different background values. Three geochemical (average metal concentrations in continental crust, average metal concentrations in shale, and average metal concentrations in non-contaminated core sediment samples) and two statistical methods (delineation method and principal component analyses) were used for calculating background values. It can be concluded that obtained information of pollution status can be more dependent on the use of background values than the index/factor chosen. The best option to assess the potential river sediment contamination is to compare obtained concentrations of analyzed elements with concentrations of mineralogically and texturally comparable, uncontaminated core sediment samples. Geochemical background values should be taken into account when establishing quality criteria for soils, sediments, and waters. Due to complexity of the local lithology, it is recommended that environmental monitoring and assessment include selection of an appropriate background values to gain understanding of the geochemistry and potential source of pollution in a given environment.

Bioaccumulation of metals in the trees of Novi Sad, Serbia.

In urban and industrial areas, higher plants are used as biomonitors of exposure. The objective of this study was to assess metals accumulation in leaves of dendroflora for the city of Novi Sad, Serbia, in May and September. The investigation was conducted at three sites in the urban area of Novi Sad. Determination of metals concentration for Al, As, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb in the sample was performed by inductively coupled plasma-optical emission spectrometry (ICP/OES). In the leaves of the examined tree species the highest concentrations were obtained for: Al, Fe, Mn, and Zn. The highest mean concentrations of metals were present in leaves of Aesculus hippocastanum in September. Trees from Liman and the Danube Park contained higher mean concentrations of metals in the leaves. In A. hippocastanum and Platanus hybrida an increase of al., As, Cr, Fe, and Pb concentrations occurred from May to September, with higher concentrations of Al and Fe noted in May. However, in Celtis australis, Juglans regia, and Tilia platypyllos there was a reduction in Al, Mn, Fe, and Zn from May to September. The basis for these findings requires further investigation, but diverse washing procedures may account partially for these observations.

Bioaccumulation of Heavy Metals and Microelements in Silver Bream (Brama brama L.), Northern Pike (Esox lucius L.), Sterlet (Acipenser ruthenus L.), and Common Carp (Cyprinus carpio L.) From Tisza River, Serbia.

The aim of this study was to determine the concentrations of Al, As, B, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Sr, and Zn in liver, gills, gonads, and brain of four ecologically different fish species in Serbia: piscivorous northern pike, benthivorous sterlet and silver bream, and omnivorous common carp. Fish were caught at four sites along the stretch of the River Tisza in the Pannonian part of Serbia during October 2010. Results revealed that heavy metals and microelements with the highest values in fish samples were Fe, Al, and Zn. The highest concentration of heavy metals and microelements was recorded in omnivorous common carp, and organs that most intensively accumulated the greatest number of metals were liver and gills, whereas the locality did not exert a marked impact on level of bioaccumulation.