A method of completely describing and analyzing the stochastic process of streamflow droughts has been recommended. All important components of streamflow droughts such as deficit, duration, time of occurrence, number of streamflow droughts in a given time interval [0, t], the largest streamflow drought deficit, and the largest streamflow drought duration in a given time interval [0, t] are taken into consideration. A streamflow drought is related here to streamflow deficit. Following the theory of the supremum of a random number of random variables a stochastic model is presented for interpretation and analysis of the largest streamflow drought deficit below a given reference discharge and the largest streamflow drought duration concerning a time interval [0, t], at a given location of a river. The method is based on the assumption that streamflow droughts are independent, identically distributed random variables and that their occurrence is subject to the Poisson probability law. This paper is actually a continuation of the previous E. Zelenhasić (1970, 1979, 1983) and P. Todorović (1970) works on the extremes in hydrology. Application of the method is made on the 58‐year record of the Sava River at Sr. Mitrovica and on the 52‐year record of Tisa River at Senta, Yugoslavia, and good agreement is found between the theoretical and empirical distribution functions for all analyzed drought components for both rivers. Only one complete example, the Sava River at Sr. Mitrovica, is given in the paper. The proposed method deals with hydrograph recessions of daily or instantaneous discharges in the region of low flows, and not with mean annual flows which were used by other investigators.

Josimov-Dundjerski J., Savić R., Belić A., Salvai A., Grabić J. (2015): Sustainability of the constructed wetland based on the characteristics in effluent. Soil & Water Res., 10: 114-120.The constructed wetland (CW) in the settlement of Gložan is the first system of its kind for wastewater treatment constructed in Vojvodina (Serbia), aimed at treating local municipal wastewater. The common reed Phragmites australis, naturally growing at the CW location, was used as biofiltering vegetation. The monitoring effectiveness of the CW was based on removing suspended solids and reducing the amount of organic matter. The eight-year long study shows that the age of the constructed wetland does not significantly affect the changes (increase) in concentration of suspended particles and organic compounds from the wastewater effluent. We proved that measured values of variables, suspended solids, and biochemical oxygen demand (BOD 5 ) of effluent belong to the same population. The chronological data series of suspended solids and BOD5 of effluent were processed using statistical tests of homogeneity, both parametric (Student's t-test with Fisher's F-test) and nonparametric (Mann-Whitney's U-test). The results of testing homogeneity of the data confirm that the constructed wetland has not been compromised, and that the removal of suspended solids is 93-96% and reduction of organic compounds, expressed in terms of BOD 5 , is up to 79-84%.

SažetakUređenje zemljišne teritorije putem komasacije ima za cilj poboljšanje uslova za poljoprivrednu proizvodnju. Poboljšanje se ogleda u grupisanju razbacanih i rascepkanih poljoprivrednih poseda u veće parcele. Nove parcele su pravilnog oblika, pogodnog za obradu savremenom poljoprivrednom mehanizacijom, sa direktnim pristupom sa mreže poljskih puteva. Kako bi se formirale pravilne parcele sa grupisanim posedom, na području je neophodno izvršiti čišćenje od skoro svih oblika vanšumskog zelenila, koje u novoj parcelaciji predstavlja prepreku. Prisustvo vanšumskog zelenila na području sa velikim procentom obradivih poljoprivrednih površina je od izuzetnog značaja. Funkcije vanšumskog zelenila se ogledaju od zaštite zemljišta od isušivanja i eolske erozije, očuvanja biodiverziteta do formiranja izgleda predela. U radu je prikazana mogućnost utvrđivanja zastupljenosti i povezanosti vanšumskog zelenila koristeći satelitske snimke dostupne preko aplikacije Google Earth. Identifikovane površine pod vanšumskim zelenilom su razvrstane kao tačkasti, linijski i površinski elementi. Korišćenjem geografskog informacionog sistema utvrđena je zastupljenost, međusobna povezanost i prostorni raspored vanšumskog zelenila na komasacijom uređenom području opštine Ada. Stanje registovano sa satelitskih snimaka je upoređeno sa stanjem koje bi se dobilo realizacijom projekta podizanja poljozaštitnih šumskih pojaseva.Ključne riječi:uređenje zemljišne teritorije, vanšumsko zelenilo, geografski informacioni sistem. UvodOsnovnu proizvodnu površinu u poljoprivrednoj proizvodnji predstavlja poljoprivredna parcela. Posed jednog gazdinstva je često sastavljen od više proizvodnih parcela. Prema podacima iz statističkog godišnjaka Republike Srbije, preko 80% poljoprivrednih površina je u vlasništvu privatnih gazdinstava. Međutim, prema istim