Dragan Dolinaj

Variability of seasonal and annual precipitation in Slovenia and its correlation with large-scale atmospheric circulation

Abstract This paper examines temporal and spatial variability and trends of annual and seasonal precipitation in Slovenia and their relationship with three atmospheric circulation patterns represented by their indices: North Atlantic Oscillation index (NAOi), Mediterranean Oscillation index (MOi) andWestern Mediterranean Oscillation index (WeMOi). Data from 45 precipitation stations were used for the period 1963–2012.Mean annual precipitation varies from 736 mm in eastern Slovenia to 2,518 mm in northwestern Slovenia. A significant annual precipitation decrease (from −3% to −6% per decade) is observed in western Slovenia. Significant negative trends are observed in southwestern Slovenia in summer (from −4% to −10% per decade) and near the Adriatic coast in spring (from −6% to −10% per decade). Non-significant negative and positive trends are observed in winter and autumn, respectively. Results indicate significant correlations between winter precipitation and MOi (from −0.3 to −0.7), NAOi (from −0.3 to −0.6) andWeMOi (from 0.3 to 0.6). Significant We-MOi influence is observed in spring and autumn, while NAOi and MOi influence has not been detected. Annual precipitation and WeMOi are significantly correlated in central and eastern Slovenia, while significant NAOi and MOi influence is observed in western Slovenia (with the larger area covered by MOi influence).

Drought Severity and its Effect on Agricultural Production in the Hungarian-Serbian Cross-Border Area

Abstract Several environmental and economic consequences of drought and the accompanying water shortage were observed in the plain area of the Carpathian Basin in the last decades. This area is mostly used for agriculture, thus it is a key problem in the future to maintain food safety in the changing circumstances. Therefore, involvement and identification of areas affected by drought hazard and revealing steps of efficient adaptation are of high importance. In this study influence of drought severity on agricultural production is investigated in the Hungarian-Serbian cross-border area. The tendency in drought severity was analysed by PaDI and MAI drought indices. The effect of drought on agricultural production is evaluated on maize yield data as the most drought sensitive crop in the region. Increasing drought frequency and severity was indicated for the study area for the period of 1961-2012. The spatial assessment of annual PaDI maps revealed the higher exposure of the north and northeastern part of the study area to drought, where drought frequency was also experienced to be the highest. Increased sensitivity was detected based on maize yield loss after the early 1990s and annual yields were in strong connection with d rought severity. In spite of the technological development of agriculture, environmental factors still substantially affect crop yie lds. The observed unfavourable changes in the region mean that water management and spatial planning faces conceptual challenges to prevent and mitigate the damages of drought.

Classification Methods for Inland Excess Water Modeling

Abstract Inland excess water floodings are a common problem in the Carpathian Basin. Nearly every year large areas are covered by water due to lack of natural runoff of superfluous water. To study the development of this phenomenon it is necessary to determine where these inundations are occurring. This research evaluates different methods to classify inland excess water occurrences on a study area covering south-east Hungary and northern Serbia. The region is susceptible to this type of flooding due to its geographical circumstances. Three separate methods are used to determine their applicability to the problem. The methods use the same input data set but differ in approach and complexity. The input data set consists of a mosaic of RapidEye medium resolution satellite images. The results of the classifications show that all three methods can be applied to the problem and provide high quality satellite based inland excess water maps over a large area.

Limnological characteristics, water regime and water quality problems of Borkovac reservoir (Vojvodina, Serbia)

In this study we present interdisciplinary investigations of the Borkovac reservoir (Vojvodina, Serbia). The limnological characteristics of the reservoir were analysed in the scope of its sustainable use for irrigation, fishing and tourism. This multipurpose water accumulation has been established in 1975 as a part of regional hydrological system of the Fruska Gora mountain region. The main environmental problems recognized in this study were: water regime, intensive sedimentation in the reservoir, enhanced water eutrophycation and toxic cyanobacterial blooms. Observed environmental problems and proposed solutions in the case of the Borkovac accumulation including construction of the sediment precipitator at the Borkovac stream junction to lake, sediment removal, artificial water mixing and oxygenation, phosphorous inactivitation, different kinds of biomanipulations and biomass removal and introduction of ecoremedation methods could also be applied to other artificial water bodies of the Fruska Gora slopes.

Statistical Analysis of Water Quality Parameters in Seven Major Serbian Rivers during 2004‒2013 Period

Rivers on territory of the Republic of Serbia can be separated to three sea drainage basins: Black, Adriatic and Aegean. Majority of rivers belong to the Black Sea drainage basin. The Danube is the most important river in Serbia and one of the most important rivers of Europe. All rivers investigated in this paper represent direct or indirect tributaries of the Danube River and as that, they are belonging to the Black Sea drainage basin. In this study, the water quality status and the spatial and temporal trends of seven major rivers in Serbia were assessed through the application of ten parameters of Water Quality Index. Ten year (2004–2013) public database of environmental data was used. Into considerations were taken differences between every river individually and difference between sample positions on every single river. Based on the chemical parameters of water quality, it can be seen that the biggest rivers in Serbia show different values of WQ parameters. The highest WQ value is measured on the Drina River, while the lowest value is measured on the Južna Morava and the Tisza River. Analyses of parameters per period of year show that there is a statistically significant difference between values during warm and cold periods.

Heat wave risk assessment and mapping in urban areas: case study for a midsized Central European city, Novi Sad (Serbia)

Risk assessment and mapping methodologies for heat waves as frequently occurring hazards in central and southeastern Europe were applied in this study, and the impact of heat waves on the mortality of urban populations was determined as part of the assessment. The methodology for conducting the heat wave risk assessment is based on European Commission’s Guidelines for Risk Assessment and Mapping. The Novi Sad (Serbia) urban area was studied during summer 2015, which was one of the hottest summers in the last few decades. In situ air temperature measurements from urban stations and mortality of urban populations were used. Nocturnal urban heat island (UHI) intensity values between the various built-up zones and natural surrounding areas were used for the hazard level calculation. Temperature data from 9 p.m. to 5 a.m. were used because during the night, the UHI intensity reached its maximum values. The average daily number of deaths by LCZs was used to define the impact level of the vulnerability index. Calculations for both hazard levels were completed during two intensive heat waves (in July and August 2015) when it was expected that there may be a high level of risk. The results and maps show that the urban area is complex, and the heat wave risk on the population is not uniform. The most densely built-up areas (LCZs 2, 5 and 6) have very high or high risk values that are influenced by a higher rate of mortality. The obtained results and maps can be used by local authorities to prevent and mitigate climate-related hazards, for medical institutions as well as urban planners and for ancillary local, regional or national services. According to these results, the local authorities could define hot spots where they can place medical and rescue teams and install points with water supplies, etc.

Correlation between discharge and water quality: Case study Nišava river: Serbia

The water quality and river discharges were surveyed at two sites in Nišava River basin (Dimitrovgrad and Niš) with complete data series for the ten-year period (2005–2014). For these stations SWQI was calculated and correlation analysis was applied. The index value is dimensionless and varies between 0 and 100 (best quality) It is derived from numerous physical, chemical, biological and microbiological parameters. At Niš station average annual value of SWQI is 78 (good) with a clear decrease trend over a ten-year period. On the other side, on Dimitrovgrad station, average annual SWQI is 89 (very good) with a clear positive trend. Goal of this paper was to determine if there is a correlation between river discharge and values of SWQI. Results of the Pearson correlation test between SWQI and daily discharge values for Dimitrovgrad station show a moderate linear relation was observed, r= -0.287, p = 0.002. On Niš station same test has shown that there is no statistically significant relation between discharge and water quality (r=0.103 p= 0.297). This study has shown that the correlation between SWQI and discharge is weak or not present at all at the investigated river.

Main characteristics of water regime of the phreatic aquifer in Subotica municipality: Vojvodina, Serbia

Introduction Formation and distribution of the phreatic (unconfined, free, first, shallow) aquifer, groundwater layer the closest to topographic surface, primarily depends on the ruling hydrogeological conditions and relations that are perceived in the presence of rocks of intergranular porosity with favourable water collecting abilities within the top (covering) geological layer and impermeable rocks in the bottom geological layer of a certain geological complex. Main characteristics of the phreatic aquifer water regime result from the series of complex and interdependent phenomena and processes whose character is defined by numerous natural and anthropogenic factors. Among the natural factors, besides above-mentioned hydrogeological conditions, it is necessary to mention pedological, geomorphologic, fitogeographical and especially climate and hydrological circumstances. However, anthropogenic factor significantly modifies the natural regime of the phreatic aquifer in the areas with appropriate hydrotechnical works conducted or intensive irrigation/drainage of cultivated land (Pavić, 2006; Pavić et al., 2006; Pennington, Cech, 2010). Abstract

The Importance of Preservation of Autochthonous Biotope of Pannonian Plane in the Area of Special Nature Reserve “Pašnjaci Velike Droplje“ for Education and Ecotourism Development

In the past the region of Vojvodina was dominated by vast steppes, saline areas, marshes and flooded terrains. Wet terrains were converted into steppes during the Holocene climate changes, but the land under cultivation is gradually taking their place, too. Autochthonous biotope is preserved in some regons of Vojvodina. These regions are under state protection. Special nature reserve “Pašnjaci velike droplje“ consists of saline areas and vast steppes and it is the only habitat of Great Bustard in Serbia. Reserve is located in north Banat. Devolpment of ecotourism is based upon endangered ornithology species, heterogeneous fauna as well as upon up the educational purpose of the reserve. There are also possibilities for organizing of photo safaris and nature schools in the reserve. In order to protect autochthonous biotope, legal regulations on protection should be obeyed, fields should be revitalized i.e. they should be transformed into former state of natural mosaic of vast steppes and saline areas.