Tourist and Ecological Study of the River Lim Valley

Dolina Lima i Polimlje predstavljaju složenu prostornu celinu u kojoj se prepliću različiti prirodni i antropogeni procesi. Analiza elemenata prirodne i sociokulturne sredine, njihovo turističko-ekološko vrednovanje i objedinjavanje treba da pokažu svrsishodnost ulaganja u turizam i ekologiju Polimlja. Tema doktorske disertacije postavljena je tako da se kroz trinaest komplementarnih poglavlja dođe do projektovanog cilja o mogućnostima razvoja pojedinih vrsta ekoturizma. Prikaz objedinjenih sadržaja u određenom obimu doprinosi boljem poznavanju Polimlja i omogućava lakši pristup operativnom delu turističkog planiranja u uslovima ekološke i turističke održivosti. Takva konstatacija proističe iz utvrđenih vrednosti dobijenih analizom parametara kvaliteta životne sredine i sociokulturne baštine. Na osnovu dobijenih vrednosti izveden je zaključak da turizam u ekološkom ambijentu Polimlja s obzirom na kvalitet prirodnih elemenata može postati dominantna delatnost i pored negativih iskustava u oblasti životne sredine iz druge polovine dvadesetog veka.The valley of the river Lim and Polimlje represent a complex regional entity in which different natural and antropogenic processes interact. Analysis of elements of the natural and socio-cultural environment, their tourist-ecological valorization and combination should show the appropriateness of investing in the tourism and ecology of Polimlje. The theme of this Ph.D. thesis is defined in such a way that through thirteen complementary chapters it arrives at the projected target about the possibillities of the development of some types of eco tourism. Presentation of the combined content to a certain degree contributes to a better knowledge of Polimlje and enables easier access to the operative part of tourist planning in conditions of ecological and tourist maintenance. Such a conclusion is the result of established values obtained by analysis of the quality of the environment and the socio-cultural heritage. Based on the values obtained it may be concluded that tourism in the ecological environment of Polimlje, having in mind the quality of natural elements, could become a dominant activity regardless of negative experiences in the environmental field in the second half of the twentieth century

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

EXPOSURE TO EARTHQUAKES — DISTRIBUTION AND CHANGE OF THE WORLD’S POPULATION WITH REGARD TO DISPOSITION OF SEISMIC ACTIVITIES

Earthquake effects can be distinctly different in two different countries even if the earthquake has the same level of intensity. Loss and damage caused by the earthquake will be much less in developed countries than in developing countries. Due to its inability to prevent and cope with disasters developing countries are in the focus in this article. This paper presents an approach for detecting the most and the least vulnerable countries of the world and the distribution of their population within different earthquake intensity zones. There is also a summary of the change in world population during the 25‑year period (1990–2015), within continents and earthquake intensity zones as well as a comparison between continents. The population growth is unevenly distributed and highest in the zone with probable maximum intensity VIII. In relation to the World population by earthquake intensity zones, the developing countries have the lowest share of its population among the zone with most destructive earthquakes

Uticaj različitog načina korišćenja zemljišta na infiltraciju vode u peskovito-ilovastim zemljištima

Human activity can significantly alter land cover characteristics and subsequently hydrological and other processes in river basin. The aim of this study was to determine infiltration of surface (0-30 cm) sandy loamy Fluvisol under natural meadow vegetation and adjacent Fluvisol which is used more than 10 years as the arable soil, with similar conditions of pedogenesis in the Nišava River Valley, in the vicinity of Pirot (Serbia). The other conditions of pedogenes were similar. Measurement of infiltration was performed by double cylindrical infiltrometer. Three infiltration runs were carried out for each location. The results showed that the in the arable soil compared with meadow, constant (steady state) infiltration rate and cumulative infiltration were about 699% and 447% higher, respectively. The change in soil structure caused by loosening of the plowing layer because of tillage is the main factor causing the increase in infiltration of water into the soil after conversion of natural grassland to arable soil. These results can be used in predicting surface runoff, saturated hydraulic conductivity of the surface layers and groundwater recharge, and also in the development or selection of the most efficient methods of irrigation sandy loam soils.Delatnost ljudi može znatno izmeniti osobine zemljišnog pokrivača, a zatim hidrološke i druge procese u rečnom slivu. U vezi s tim, obavljena su uporedna terenska istraživanja u cilju utvrđivanja infiltracije vode u površinskom horizontu (0-30 cm) bestrukturnog, peskovito-ilovastog, slabo humoznog distričnog fluvisola pod prirodnom livadskom vegetacijom i sličnog fluvisola koji se koristi više od 10 godina kao njivsko zemljište, u dolini reke Nišave, u okolini Pirota (Srbija). Ostali uslovi pedogeneze bili su im slični. Merenje infiltracije vršeno je pomoću duplih cilindričnih infiltrometara. Na svakoj lokaciji obavljena su po tri merenja infiltracionih karakteristika istraženih zemljišta. Rezultati su pokazali da su u obrađivanom zemljištu konstantna (ustaljena) brzina infiltracije i kumulativna infiltracija veće za oko 699%, odnosno 447% u poređenju sa prirodnom livadom. Promena građe zemljišta uzrokovana rastresanjem oraničnog horizonta pri obavljanju agrotehničkih operacija glavni je faktor koji je uzrokovao povećanje brzine infiltracije vode nakon prevođenja prirodnih livada u oranice. Rezultati ovog istraživanja mogu se koristiti u predviđanju površinskog oticanja, zasićene hidrauličke provodljivosti površinskh slojeva zemljišta i popunjavanja zaliha podzemnih voda, a takođe i u razvoju ili odabiru najefikasnijih metoda za navodnjavanje peskovito ilovastih zemljišta

Uticaj režima navodnjavanja na prinos i komponente prinosa soje

This study examines the effects of different irrigation regimes on seed yield and yield components of sprinkler-irrigated soya bean [(Glycine max (L.) Merr.] under field conditions in 2006, 2007 and 2008 in Zemun Polje (Srem, Srbija). Four irrigation regimes: 80-85% (T1), 70-75% (T2), 60-65% (T3) of field capacity, and non-irrigated regime (T0) were evaluated each experimental year. The experimental design was a randomised complete block with four replications on a Calcaric Chernozem. Water stress (drought) during growing season in the non-irrigated treatment (T0) decreased plant physiological activity, vegetative growth, and productivity of soya bean. Irrigation treatments significantly (P lt 0.01) influenced soya bean seed yield and yield components. The treatment T2 produced higher seed yield than T1 and T3. Irrigation regimes had statistically significant different effects on yield components such as the plant height at harvest, number of pods per plant, number of seeds per plant, mass of pod with seeds per plant, 1,000 seed mass and hectoliter mass of soya bean seeds. Yield reduction was mainly due to a lower number of pods and seeds per plant and lower seed mass. The T1 treatment had the highest plant height of soya bean in all three growing years. The results have shown that under water scarcity, the treatment T3 is an acceptable irrigation strategy to stabilize and increase soya bean yield in Srem and neighboring countries in the region, provided that this practice is not prevented by economic constraints.U ovom radu ispituje se uticaj različitih režima navodnjavanja orošavanjem na prinos i komponente prinosa semena soje [(Glycine max (L.) Merr.] u poljskim uslovima u 2006, 2007. i 2008. godini u Zemun Polju (Srem, Srbija). Svake godine istraživana su po tri režima navodnjavanja, i to sa 80-85% (T1), 70-75% (T2), 60-65% (T3) poljskog vodnog kapaciteta i prirodni vodni režim bez navodnjavnja (T0). Ogled je izveden po metodi slučajnog blok sistema u četiri ponavljanja na karbonatnom černozemu. Deficit vode u toku vegetacionog perioda u nenavodnjavanom tretmanu (T0) smanjio je fiziološku aktivnost biljaka, vegetativni rast i produktivnost soje. Navodnjavani tretmani su vrlo značajno (P lt 0,01) uticali na prinos zrna soje i komponente prinosa. Na tretmanu T2 postignut je veći prinos semena nego na tretmanima T1 i T3. Iako je tretman T2 dobio oko 37% manje vode za navodnjavanje u poređenju sa T1, prinos soje povećan je u proseku za 11%. Navodnjavani režimi imali su statistički značajno različite uticaje na komponente prinosa kao što su visina biljaka u vreme žetve, broj mahuna i zrna po biljci, masa mahuna po biljci, masa zrna po biljci, masa 1.000 zrna i zapreminska masa zrna. Smanjenje prinosa je uglavnom posledica manjeg broja mahuna i zrna po biljci i manje mase 1.000 zrna. Tretman T1 imao je najveću visinu biljaka u sve tri godine ispitivanja. Rezultati su pokazali da je tretman T3 prihvatljiva strategija navodnjavanja za stabilizaciju i povećanje prinosa soje u Sremu i susednim zemljama regiona u uslovima ograničenih vodnih resursa, pod uslovom da ova praksa nije sprečena ekonomskim ograničenjima

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

Liming increases alfalfa yield and crude protein content in an acidic silty loam soil

A three year field trial examined the effect of three hydrated lime (HL, Ca(OH)2) rates (0, 1.5 and 3 Mg HL ha-1) on yield and quality characteristics of alfalfa on an acid soil (pHwater 1:2.5 4.7) in Western Serbia. Lime was applied only once. Total dry mass yields of a new planting alfalfa (Medicago sativa L.) increased up to 6500% by the treatments of HL, compared with the untreated control. Lime application significantly (P ≤ 0.05) increased the crude protein content of alfalfa, in comparison to the no limed control. Liming also significantly increased Ca, K, and P concentrations but decreased Mg, Fe, Mn, Zn, and Al concentrations in alfalfa tissue, compared with the control treatment. Alfalfa yield increase was attributed to the increase of Ca, P and K uptake. Furthermore, the low (1.5 Mg HL ha-1) and high (3 Mg HL ha-1) lime treatments increased soil pH even further by 0.9 and 1.5 pH units, respectively. The results suggest that an initial application of hydrated lime at a rate of 3 Mg HL ha-1 may ameliorate soil acidity and increase the yield and quality characteristics of alfalfa at least over a 3-year period.Keywords: Alfalfa, soil acidity, liming, herbage yield, elemental compositio

The conversion of forestland into agricultural land without appropriate measures to conserve SOM leads to the degradation of physical and rheological soil properties

This study was conducted to compare soil particle density (ρs), soil total porosity (TP), liquid limit (LL), plastic limit (PL), and plasticity index, and their relations with soil organic matter (SOM), of non-carbonate silty clay Fluvisols under different land uses. Three neighboring land uses were studied: native deciduous forest, arable land, and meadow, managed in the same way for more than 100 years. Soil was collected from 27 soil profiles and from three depths (0–15, 15–30 and 30–45 cm). Land use caused statistically significant but different impacts on soil properties, particularly in the topsoil. The forest topsoil measured the lowest ρs and bulk density (ρb) but the highest SOM and soil water content at PL, compared to meadow and arable soil. Statistically significant linear relationship was observed with the SOM content and ρs (− 0.851**), ρb (− 0.567**), calculated TP (0.567**) and measured TP (− 0.280**). There was a nonlinear relationship between SOM and LL (0.704**) and PL (0.845**) at the topsoil. The findings suggested that SOM content strongly affected ρs, ρb, TP, LL and LP. This regional study showed that the conversion of forestland into agricultural land without appropriate measures to conserve SOM leads to the degradation of physical and rheological soil properties

IMPACT OF GRAZING ON SOIL ORGANIC MATTER AND PHYSICAL PROPERTIES OF A FLUVISOL IN NORTWEST SERBIA

The effects of long-term (>20 yr) grazing on the selected physical properties of a non carbonated silty-clay Fluvisols were studied in the region of the Kolubara Valley, Northwest Serbia. Two adjacent land-use types (native deciduous forest and natural pasture soils converted from forests for more than 20 years) were chosen for the study. Disturbed and undisturbed soil samples were collected from three sites at each of the two different land-use types from the depths of 0–15, 15–30 and 30–45 cm. In relation to the soil under native forest, soil organic matter content, total porosity and air-filled porosity were significantly reduced after long-term of grazing. The bulk density (0.99–1.48 g cm–3) and the saturated hydraulic conductivity (6.9.10–2–3.2.10–4 cm s–1) were significantly lower in forest compared to the adjacent pasture (ex-forest) soil (1.49–1.55 g cm–3 and 3.4.10–4–5.5.10–4 cm s–1, respectively). In addition, forest had significantly lower dry mean weight diameter (7.0–9.2 mm) and greater wet mean weight diameter (2.0–2.6 mm) for 0–45 cm depth compared with the pasture (8.8–9.4 mm and 1.8–2.3 mm, respectively). The decrease of soil organic matter content and reduction in aggregate stability under long-term grazing rendered the soil more susceptible to compaction. In conclusion, the results of this study indicate that removal of permanent vegetation in the conversion process from forest areas to pasture land may lead to loss of soil productivity and serious soil degradation. Obviously, there is a need for greater attention to developing sustainable land use practices in management of these ecosystems to prevent further degradation of pasture soils in the region

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