Ljubomir Letić

Procedure for underground water calculation regime of pedunculata oak habitat in plain Srem.

The calculation of the influence of the underground water level on the habitat conditions of pedunculate oak in the lowland Ravni Srem is presented. The management method in these forests is greatly determined by moisture regime. Hydrogeological conditions are significant factors of moisture distribution in the soil during the vegetation period. In the river Sava alluvial deposits in Ravni Srem, the serried type of aquifer was formed, mostly of subartesian character, connected with river waters by hydraulic connection. The calculation of underground water regime was adapted to the conditions of two-layer porous environment in the river Sava alluvium, in order to define the oscillations of piezometric pressure in the lower aquifer and the level of underground waters in the upper, less porous layer.

Monitoring kvaliteta vode i sedimenta manjih vodotoka u Vojvodini - primer vodotoka Tatarnica

U radu se analizira stanje kvaliteta vode i sedimenata kanalisanog vodotoka Tatarnica. Ovaj vodotok predstavlja i glavni kanal jednog od sistema za odvodnjavanje, koji je lociran dvadesetak kilometara zapadno od Novog Sada (Vojvodina, Srbija). Kvalitet vode i sedimenta ovog vodotoka, pored ostalog, znacajan je zbog toga sto se njegove vode koriste za navodnjavanje povrtarskih kultura na okolnim obradivim povrsinama ali i zbog toga sto se uliva u Dunav u zoni akvatorije posebne ekoloske vrednosti, parka prirode Begecka jama. Na osnovu mesecnog uzorkovanja vode i analize relevantnih indikatora kvaliteta, tokom perioda 2006-2012. godine, prikazani su rezultati sedmogodisnjeg monitoringa kvaliteta vode i sedimenata. Prema vecini relevantnih parametara kvaliteta, u najvecem broju uzoraka, voda ima dobar ekoloski potencijal. Međutim, konstatovana je i povremena pojava vode neodgovarajuceg kvaliteta, najcesce kada je u pitanju organsko zagađenje iskazano preko povecanih vrednosti bioloske i hemijske potrosnje kiseonika (BPK 5 i HPK) kod oko 35% uzoraka. Odstupanja od zahtevanog kvaliteta vode konstatovana su i kod ostalih parametara u oko 10-25% uzoraka. Sastav sedimenata, po svim razmatranim parametrima, uglavnom je u granicama koje nemaju negativne posledice na životnu sredinu u kanalu i njegovom okruženju.

Representation of certain indicators o climate change in the area of eastern Serbia in the period 1991-2012 compared to the reference period 1961-1990

Climate change that has occurred at the end of the last and at the beginning of this century, among other things, has a certain impact on forests as well. For the territory of Eastern Serbia, for two periods of climate observations, the reference period 1961-1990 and the period 1991-2012, a comparative analysis of the following climatic elements was done: air temperature, amount of precipitation and relative humidity of air. Calculations were performed on the basis of collected and systematized data from 11 meteorological stations (6 synoptic/main climatological and 5 regular climatological) that were part of the Republic Hydrometeorological Service, situated in the area of Eastern Serbia. Analysis of the anomalies of air temperature and precipitation as indicators of climate change for the period 1991-2012 compared to the reference period 1961-1990 was done separately for each of the four seasons (winter, spring, summer, autumn) and summarized for each period. The results of the comparative analysis show that in the period 1991-2012 compared to the reference period 1961-1990, there was an increase in the average annual air temperature, as well as the increase in the average air temperature for all four seasons, and a decrease in the average annual amounts of precipitation and the decrease in the relative humidity of air. [Projekat Ministarstva nauke Republike Srbije, br. 37008]

Formation of useful waters on the Stara Planina Mountain, in the area Visok Kraj.

Formation and discharge of useful waters was studied on southwestern slopes of the Stara Planina Mountain, in the area Visok Kraj that is the typical hilly-mountainous region in East Serbia. The catchment’s area of Dojkinacka River was chosen due to numerous and specific edaphic properties. Pump forests (association: Fagetum moesiacea serbicum Rud.) dominate here and were mostly developed on slightly acidic, humus-silicate or on acidic brownish soil. Soils are of a range of depths and development of pedogenetic processes. The aim of this work is to highlight elements that have pronounced influence on supply of useful and small water bodies in the catchment area of Dojkinacka River. Complex relations between geological setting, climate conditions, pedological characteristics, hydrological and hydrogeological conditions, forest vegetation etc. were analyzed. Elements that are significant for proper evaluation of useful water or small domains supply were in this case detected through water balance methods, geological mapping and tracking. It was deduced that the disagreement of topographic and hydrological catchment’s area of Dojkinacka River represents the significant element which should be taken into consideration in order to determine the real reserves of useful, i.e. small water domains.