Uticaj promene načina korišćenja zemljišta na strukturu livadske crnice u zapadnoj Srbiji

Changes in land use can significantly affect aggregate distribution and water stability of structural aggregates. This study was conducted in the Kolubara River Valley, Western Serbia, to determine the effects of land use changes on composition and water stability of aggregates in humus horizons (0-30 cm) of noncarbonated Gleyic Fluvisols. This study was conducted at nine sites, where each site contained two adjacent land uses of natural grassland and arable land which underwent crop rotation for >100 years. Soil samples were taken from depths of 0-10, 10-20 and 20-30 cm for each land use. When the grassland was converted into arable land, the content of the agronomically most valuable aggregates (0.25-10 mm) of cultivated soils for a depth of 0-30 cm was significantly reduced by 22-40%, while the percentage of cloddy aggregates (>10 mm) increased by 41-68%, compared to grassland. In addition, the long-term arable soil had significantly (p lt 0.05) lower aggregate stability, determined by wet sieving, than grassland. The lowest aggregate stability was found in aggregates > 3 mm. Their content is ≈ 2.3 times lower in arable soil (12.6%) than in grassland (28.6%) at a depth of 0-10 cm. In addition, meanweight diameters of dry and wetstable aggregates and structure coefficient showed significant differences between land use at a depth of 0-30 cm. The results showed that the conversion of natural grassland to arable land in the lowland ecosystems of Western Serbia degraded aggregate distribution and stability.Istraživanja su sprovedena u dolini reke Kolubare da bi se utvrdili efekti promene načina korišćenja zemljišta na agregatni sastav i vodootpornost strukturnih agregata u humusnom horizontu (0-30 cm) beskarbonatne livadske crnice. Izabrano je devet lokacija koje su na bliskom rastojanju imale površine pod prirodnom livadskom vegetacijom i oranice koje su stvorene pre više od 100 godina razoravanjem prirodnih livada. Nakon razoravanja prirodnih livada i njihovog pretvaranja u oranice, sadržaj agronomski najpovoljnijih strukturnih agregata (prečnika 0,25-10 mm) u oranicama na dubini 0-30 cm, značajno je smanjen, za 22-40%, dok je sadržaj grudvastih agregata (>10 mm) povećan za 41-68 %, u poređenju sa livadom. Pored toga, višegodišnje oranice imaju značajno (p lt 0,05) manju vodootpornost strukturnih agregata, određenih mokrim prosejavanjem, od livada. Najmanju vodootpornost pokazali su strukturni agregati prečnika >3 mm. Takođe, prosečni maseni prečnici suvih i vodootpornih agregata i koeficijent strukture pokazali su značajne razlike između različitih načina korišćenja zemljišta na dubini 0-30 cm. Razoravanje livadskih crnica pod prirodnom livadskom vegetacijom istraženog područja i njihova višegodišnja obrada doveli su do značajnih negativnih promena agregatnog sastava i smanjenja vodootpornosti strukturnih agregata

Population doses from terrestrial gamma exposure in Belgrade (Serbia) and their relation to geological setting

Terrestrial radiation exposure emitted from naturally occurring radionuclides, such as 40K and radionuclides from the 238U and 232Th series and their decay products represent the main external source of irradation to human body. The purpose of this study was to provide the assessment of the doses from terrestrial exposure of population in Belgrade. The gamma dose rate, annual effective doses and external hazard indexes due to terrestrial natural occurring radionuclides (226Ra, 232Th, 40K) were calculated based on their activities in soil samples in Belgrade determined by gamma-ray spectrometry. The mean value of the total absorbed gamma dose rate outdoors due to terrestrial radionuclides for Belgrade was 59 nGy/h which is close to the worldwide average value (58 nGy/h). The values of the gamma dose rate varied among sampling locations as a consequence of different geological formations in the investigated area. The mean value of annual effective dose of 73 Sv was significantly lower than the maximum allowed dose of 1 mSv for the population and was consistent with the worldwide average value. The mean value of external hazard index was found to be 0.28. The results of this assessment study pointed out that there is no significant radiation risk to the population of Belgrade due to terrestrial exposure to radiation from natural sources outdoors.I International Conference on Radiation in Various Fields of Research : RAD 2017 : book of abstracts; April 25-27, 2012; Niš, Serbi

Assessment of soil erosion rates in Southeastern Serbia using nuclear techniques

Erozija zemljišta vodom predstavlja vaţan problem zaštite ţivotne sredine u Srbiji. Posledica erozije je degradacija zemljišnih resursa, smanjenje plodnosti zemljišta i redukcija poljoprivredne proizvodnje. Najveši intenzitet erozije uoţen je na obradivom zemljištu na strmim padinama. Pretvaranje pašnjaka u obradivo zemljište uticalo je na povešanje prostora zahvašenih procesom erozije. U ovom radu prikazani su preli-minarni rezultati projekta tehniţke saradnje sa MeŤunarodnom agencijom za atomsku energiju ̳Jaţanje kapaciteta za procenu intenziteta erozije zemljišta koriššenjem nuklearnih tehnika u cilju podrške odrţivom upravljanju zemljištem‘ (SRB5003) ţiji je cilj procena intenziteta erozije zemljišta 137Cs-metodom. Istraţivanja sprovedena u basenima Pţinje i Juţne Morave ukazala su na intenzivnu eroziju na ovom prostoru. Istraţivanja še biti nastavljena na nekoliko drugih lokacija, a rezultati še biti upotrebljeni za podršku nacionalnim programima konzervacije zemljišta.Soil erosion by water presents an important environmental problem in Serbia resulting in degradation of the soil resources, reducing soil fertility and agricultural production. The highest intensity of erosion was observed at cultivated land occupying steep slopes. The conversion of pastures to arable land enhances this problem. This study presents the preliminary results of Technical Cooperation Project of International Atomic Energy Agency ̳Strengthening the Capacities for Soil Erosion Assessment Using Nuclear Techniques to Support Implementation of Sustainable Land Management Practices‘(SRB5003) aimed at estimation of soil erosion rates using the 137Cs-method. The investigation of Pčinja and South Morava River Basins in southeastern Serbia revealed intensive erosion in the area. The investigation will continue at several other sites and the results will be used to support national soil conservation policy.Proceedings: [http://vinar.vin.bg.ac.rs/handle/123456789/8681]XXX симпозијум ДЗЗСЦГ (Друштва за заштиту од зрачења Србије и Црне Горе), 2- 4. октобар 2019. године, Дивчибаре, Србиј

Vertical distribution of 137Cs in the undisturbed soil profiles in the basin of pčinja river, southeastern serbia

The 137Cs activity concentrations in six undisturbed soil profiles collected during 2013 in the basin of Pčinja River, southeastern Serbia, were determined gamma-ray spectrometrically. Average value of six undisturbed soil profiles by layers was calculated and vertical distribution of 137Cs activity concentration at 5 cm interval samples was shown by average profile. The 137Cs activity concentrations varied between 0.29 and 70.9 Bq kg-1 with a mean of 10.7 Bq kg-1. Even 27 years after Chernobyl accident 74% of deposited 137Cs was found in the first 20 cm of the soil

Assessment of soil erosion rates in Southeastern Serbia using nuclear techniques

Erozija zemljišta vodom predstavlja vaţan problem zaštite ţivotne sredine u Srbiji. Posledica erozije je degradacija zemljišnih resursa, smanjenje plodnosti zemljišta i redukcija poljoprivredne proizvodnje. Najveši intenzitet erozije uoţen je na obradivom zemljištu na strmim padinama. Pretvaranje pašnjaka u obradivo zemljište uticalo je na povešanje prostora zahvašenih procesom erozije. U ovom radu prikazani su preli-minarni rezultati projekta tehniţke saradnje sa MeŤunarodnom agencijom za atomsku energiju ̳Jaţanje kapaciteta za procenu intenziteta erozije zemljišta koriššenjem nuklearnih tehnika u cilju podrške odrţivom upravljanju zemljištem‘ (SRB5003) ţiji je cilj procena intenziteta erozije zemljišta 137Cs-metodom. Istraţivanja sprovedena u basenima Pţinje i Juţne Morave ukazala su na intenzivnu eroziju na ovom prostoru. Istraţivanja še biti nastavljena na nekoliko drugih lokacija, a rezultati še biti upotrebljeni za podršku nacionalnim programima konzervacije zemljišta.Soil erosion by water presents an important environmental problem in Serbia resulting in degradation of the soil resources, reducing soil fertility and agricultural production. The highest intensity of erosion was observed at cultivated land occupying steep slopes. The conversion of pastures to arable land enhances this problem. This study presents the preliminary results of Technical Cooperation Project of International Atomic Energy Agency ̳Strengthening the Capacities for Soil Erosion Assessment Using Nuclear Techniques to Support Implementation of Sustainable Land Management Practices‘(SRB5003) aimed at estimation of soil erosion rates using the 137Cs-method. The investigation of Pčinja and South Morava River Basins in southeastern Serbia revealed intensive erosion in the area. The investigation will continue at several other sites and the results will be used to support national soil conservation policy.Proceedings: [http://vinar.vin.bg.ac.rs/handle/123456789/8681]XXX симпозијум ДЗЗСЦГ (Друштва за заштиту од зрачења Србије и Црне Горе), 2- 4. октобар 2019. године, Дивчибаре, Србиј

The Natural Radionuclides in Soils of Subotica (Serbia): Distribution and Corresponding Gamma Dose Rates

The activity concentrations of K-40, Ra-226 and Th-232 from 50 locations on the territory of Subotica, North Serbia, were determined by gamma ray spectrometry. Based on the activity concentrations of investigated radionuclides, the absorbed gamma dose rate in the air was calculated. The mean values of activity concentrations were found to be 290 Bq/kg for K-40, 20 Bq/kg for Ra-226 and 18 Bq/kg for Th-232. The total absorbed gamma dose rate varied between 24 and 46 nGy/h. The mean value of 32 nGy/h was lower than the world average value.4th International Conference on Radiation and Applications in Various Fields of Research (RAD), Proceedings, May 23-27, 2016, Nis, Serbi

The potential of sustainable tourism development at the Stara mountain

In the past, the greatest part of the Stara mountain had been subjected to anthropogenic processes which induced serious ecologic consequences and diminished the worth of the potential for tourism development. The present study investigates the possibilities for the development of sustainable tourism of the Stara mountain with focus on analyzing the natural environment and the consequences that may be induced by preparations for more intensive tourist exploitation (technical interventions). The importance is stressed of anti-erosion protection and of the measures for improvement of biodiversity and geo-diversity of the Stara mountain. The necessity of finding the modes of more rational exploitation of natural and anthropogenic qualities of the Stara mountain is indicated

Spatial distribution of the Ra-226 activity concentrations in well and spring waters in Serbia and their relation to geological formations

A survey of radium activity concentrations in well and spring waters in Serbia was conducted and their correlations with geological formations were analysed. Water samples were collected from 170 sampling sites and analysed by gamma-ray spectrometry. The mean activity concentrations of Ra-226 were found to be 0.36 Bq L-1 and 0.57 Bq L-1 in well and spring waters, respectively. In more than 90% of the analysed waters the Ra-226 activity concentrations were below 1 Bq L-1. The highest activity concentrations of this radionuclide (up to 17 Bq L-1) were found in crystalline rocks- and carbon dioxide rich-aquifers. The mapping results provide a baseline to identify regions that may require additional assessment of radiation exposure by local communities. (C) 2011 Elsevier By. All rights reserved

Assessment of radiation exposure to human and non-human biota due to natural radionuclides in terrestrial environment of Belgrade, the capital of Serbia

The main focus of this study was to assess radiation exposure to human and non-human biota due to natural radionuclides in soil of the Serbian capital. For the first time, ERICA tool was employed for calculation of gamma dose rates to non-human biota in this area. In analyzed soils, the mean values of Ra-226, Th-232 and K-40 specific activities were found to be 35, 43 and 490 Bq kg(-1), respectively. The distribution of analyzed natural radionuclides in soils was discussed in respect to its statistically significant correlations with sand, silt, clay, carbonates, cation exchange capacity and pH value. The annual outdoor effective dose rates to the population varied from 48 to 98 mu Sv, and the total dose rates to terrestrial biota, calculated by ERICA tool, varied from 9.84 x 10(-2) mu Gy h(-1) (for tree) to 5.54 x 10(+0) mu Gy h(-1) (for lichen and bryophytes). The results obtained could serve as a baseline data for the assessment of possible anthropogenic enhancement of the total dose rate to human and non-human biota of the study area

Environmental assessment of heavy metals around the largest coal fired power plant in Serbia

Anthropogenic activities may lead to increased levels of heavy metals in soil environment and to reduced environmental quality. In this study concentrations of heavy metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V, Zn) were measured by using an atomic absorption spectrometer and soil samples were collected in the vicinity of the largest coal fired power plant in Serbia. The soil pollution status was assessed and enrichment by heavy metals at some sampling sites was revealed. For investigated metals the enrichment factors were in the range of 0.3 to 15.5, while the mean values indicated deficient to minimal enrichment of heavy metals in the investigated area. The highest contamination factor was determined for Ni, followed by Zn, Co and Cd. Cluster analysis was used to identify associations between heavy metals and soil properties. Significant positive correlations were found between: (1) Cd and Mn, Ni, Pb, Zn; (2) Cr and Cu, Fe, Ni, Pb; (3) Zn and Cu, Ni, Pb; and (4) Fe and V. Spatial distribution maps of heavy metal contents based on geostatistical analysis indicated similar patterns of spatial distribution for Co, Fe and V as well as for Cd, Mn, Ni and Pb. The hot spots for Co, Cr, Cu and Zn were revealed between two blocks of coal fired power plant in the investigated area. The distribution pattern revealed that the highest concentrations matched the predominant wind directions. It may be concluded that operation of the coal fired power plant has no significant negative impact on the surrounding environment with regard to the content of investigated heavy metals. (C) 2015 Elsevier B.V. All rights reserved