Neven Kuspilic

Polaziste istraživanja je utvrđivanje utjecaja poljoprivrede na koncentracije nitrata u podzemnim vodama u odabranim nitratno ranjivim podrucjima (Varaždinska i Međimurska, Vukovarsko-srijemska županija) u kontinentalnom dijelu Republike Hrvatske. Cilj je utvrđivanje trenda u izmjerenim koncentracijama nitrata na 24 postaje motrenja kakvoce podzemne vode iz nacionalnog monitoringa unutar definiranih podrucja primjenom Mann- Kendallovog testa trenda. Aritmeticka sredina koncentracija NO3- prelazi MDK od 50 mg l-1 na 5 tocaka monitoringa ; 4 u Varaždinskoj i Međimurskoj županiji, a 1 u Vukovarsko-srijemskoj županiji. Na 12 postaja je utvrđen pozitivan trend (na 5 postaja je statisticki znacajan), a na 7 postaja negativan trend (na 5 postaja je statisticki znacajan), ali prema kategoriji koristenja poljoprivrednog zemljista na kojoj se nalazi pojedina tocka motrenja nije moguce definirati koje kulture dominantno utjecu na pozitivan trend koncentracije nitrata.

Inland water ports are key components of the entire transport system on inland waterways, and the success of complex transport process from the point of production to the point of final consumption is greatly dependent on them. Inland ports, situated on European waterways, with regard to the integral character of the transport and general economic market, are of particular importance. On the long-term basis, orientation of the European Community is to establish balance of transport development, stressing inland waterways and railways as alternative means of transport. This opens the opportunity for expansion of ports on inland waters. This refers mainly to ports in Eastern European Danubian Countries, where this fact is expected to influence directing of transport from Near East transport markets to the Danubian corridor and further to Western European countries. In Croatia, four port authorities are organized on inland waterways, as follows: in Vukovar for public ports on the Danube and the future Danube-Sava multipurpose canal, in Osijek for the Drava ports, while the jurisdiction on the Sava river is shared by the port authorities Sisak and Slavonski Brod. The Croatian ports system practically consists of four ports open to public transport of national importance: Sisak, Slavonski Brod, Osijek and Vukovar. Three of them (Slavonski Brod, Osije and Vukovar) are situated in the close vicinity of the transport corridor V c, while the ports Sisak and Slavonski Brod are situated along the transport corridor X. Their development will be greatly influenced by the importance of the transport corridors in the general traffic of the region, and vice versa. Master plans have been prepared for the ports Slavonski Brod, Osijek and Vukovar which imply their expansion, both as regards the reloading capacity and the operating space. Each of them has its specific properties resulting from the present situation, available space and physical and tranpost characteristics of their respective waterways. For the Sisak port the development plan has not been elaborated yet. Planned development of the Vukovar port includes modernizing and construction of additional port capacities in the existing port area, expansion of the port perimeter and integration with the industrial and economic zone of Borovo, investments in port infrastructure, inclusion of the port in the development of the industrial hinterland, modernizing of road and railway infrastructure in the port and in the access to the port, including connection to the major transport corridors (V c, X). The development plan of the Osijek port includes expansion of the port area to the total of 110 hectares and inclusion of the stretch from the Drava river km 12+600 to 15+490. The Plan also envisages inclusion of the island created by shortcutting the old Drava meander, and the present port area of 58.3 ha (aquatory 20.4 ha + territory 37.9 ha) will be extended to 10 ha of new territory. The development of the port Slavonski Brod is greatly dependent on the reliability and safety of navigation in the Sava river. The only present capacity in this port is reloading of crude oil in local transport to the Sisak port. In the final stage of development, the port Slavonski Brod would include 9 berths, specialized for reloading of general cargo, containers, gravel and sand, ro-ro transport, reloading of cereals, and for trans-shipment. The new Vukovar port on km 9 of the Danube-Sava Canal is envisaged within the scope of the Multipurpose Danube-Sava Canal Project. Development of this port depends on the development of transport and economic requirements and technical conditions. The forecast of future port traffic is about 5.7 million tons per annum in 30-years period (4.16 million tons per annum of water transport, and 1.56 tons of land transport). The port zone for water transport (trans-shipment) would consist of 3 port basins with 24 berths. The hinterland port zone would be connected to land transport, and would include the land terminal, production zone, trade and business zone, and commodity reserves. The facilities resulting from construction of this business zone would allow the increase of the traffic and production over 8 million tons per annum.

Focus of this research is on testing the applicability of the available empirical equations on scouring around piers of 7 bridges over large Croatian rivers: Danube, Drava, Sava and Kupa. Potential scour depth estimation for each bridge is calculated using empirical equations and compared to the depth of scour hole obtained from field measurements. Using calculated and measured data in comparison with foundation type and depth potential threat on bridge stability is evaluated.

The present state of the development of the catchment area gravitating towards the Multi-Purpose Canal Danube-Sava (MPCDS) enables partial water management, mainly for the purposes of drainage - flood control. The construction of the MPCDS will open a possibility for efficient management of waters in all the three aspects: flood control, water protection, and water utilisation. For the realisation of that goal it is necessary to build in the vicinity of the canal a number of water engineering structures, respecting the present state of the catchment area development and including the existing structures into the new system. The paper presents the selected system of water management in the MPCDS catchment area.

In this paper the authors developed an analytical procedure for predicting the dynamic displacement response of fixed offshore structures to the action of deep water random waves and uniform current. The structure is idealized as a linear onedegree of freedom system and the generalized co-ordinate system is chosen for assessing the structure's properties for which a suitable sinusoidal shape function is assumed. The transfer functions and the spectra of the generalized load and of the generalized displacement response of fixed offshore structures, depending on an adequate basic arrangement of vertical cylindrical piles and the wave-current propagation angle, are defined by applying the spectral analysis method. A numerical example is included to demonstrate the potential of the analytical model and to quantify the effects of the presence of current on the structural load and response.

Sava, Drava and Danube are three large Croatian rivers. Beside being major water recipients of large Croatian areas, water management's relevance of these rivers is great. In the past they were the subject of many regulation actions and river modifications. In the 70's and 80's significant decrease of the water surface elevation was measured. All rivers are navigable on these sequences, and channel geometry changes have a large impact on navigability purpose. On the river Sava additional issue is water level degradation, which causes problems in the use of rivers. It is possible to make strong relation between river bed degradation and water-level degradation. Additional river bed degradation is caused by gravel exploitation and dredging for increasing waterway depth.

Rijeka Drava kao recipijent s velikim vodnogospodarskim znacenjem, ima stalnu tendenciju produbljenja korita. Razlozi tih promjena su visestruki, a uglavnom uvjetovani antropogenim aktivnostima na vodotoku i slivu. Morfoloske promjene ocituju se na izmjeni prirodnog režima voda i nanosa. Prilikom provedbe radova na vodotocima i njihovom slivu, nužno je pracenje promjena na vodotoku kako bi se blagovremeno moglo reagirati ukoliko se pojave neželjeni ucinci. Prirodni vodotoci predstavljaju relativno stabilan sustav kod kojeg se umjetnim promjenama narusava prirodna ravnoteža. Unutar novih okolnosti vodotoci teže postizanju nove dinamicke ravnoteže. Na rijeci Dravi, kod luke Osijek, prije dvadesetak godina izveden je prokop. U tom periodu prokop je "sazrio" i poprimio oblik dinamicke ravnoteže uz aktivno staro korito. Na starom koritu 2005. godine izvedena je pregrada, cime su stvoreni novi uvjeti za daljnji razvoj prokopa. Promjene u geometriji prokopa te hidrolosko-hidraulickih parametara mjerene su dubinomjerom i ultrazvucnim mjeracem protoka. Temeljem prikupljenih podataka može se teorijski dati ocjena globalne stabilnosti korita. U clanku je dana metodologija pracenja hidromorfoloskih parametara te su dani preliminarni rezultati ocjene stabilnosti korita u prokopu.

The river Sava has large importance in water management of the Republic of Croatia. In recent period, large attention is given to the maintenance and navigability setting of the river, which is in conjunction with Croatian international obligations resulted from AGN agreement. The river Sava is navigable on its major reach, and future river regulation actions should contribute to the necessity of undisturbed inland navigation. On the other hand, regulation actions may not exceed the scope of the natural river characteristics. Morphological analysis according to the regime theory gives an overview of the river natural and evaluated project condition. The idea is to examine hydraulical and geometrical characteristics of the river channel. Such analysis was carried out for Jamena-Samac reach, with evident channel stability level.

This paper presents the results of monitoring of meander cute cut-off in send-bed river. Hydrologic-hydraulic data were collected on 24 control cross-sections on ten occasions during one year. The water levels were recorded using RTK- GPS, and data on the bedform, velocity profiles and discharges were collected using 4 beam broadband ADCP with frequency of 1200 kHz. Measurements were performed during low, medium and high flows. On a section somewhat longer than the cut-off itself, a 1-d morphodynamic model was constructed by using HEC-RAS 4.0 software. The paper gives an overview of the methodology of data collection and the results of estimated bedforms by using various methods of sediment transport calculation. The calculated bedforms were compared to the measured data. Parameters used for the evaluation of different methods of bedform prediction are hydraulic depth , river channel level and width of the water surface B. The calculation of river bedforms was made through the quasi-dynamic 1-d morphodynamic model for a period of one year. There were also surveys of the river bed on cut-off in this period, and thus calculated and measured bedforms could be compared. The dynamic boundary conditions were recorded discharges at the upstream boundary and recorded water levels on the downstream boundary, and estimated incoming sediment load on the basis of the existing sediment load curve. The bedforms were calculated for several methods of sediment transport calculation: Ackers-White, Engelund- Hansen, Laursen, Meyer-Peter-Muller, Toffaleti and Yang. Hydrologic and hydraulic characteristics of the monitored watercourse are in the range of validity of all mentioned methods, but it should be emphasized that the Meyer-Peter-Muller method is valid predominantly for gravel river bed material. The paper also presents a sensitivity analysis for a certain morphological parameter in the numerical model. The sensitivity analysis was performed for: incoming sediment load, river bed material, sediment specific gravity, particle settling velocity and water temperature.

Retentions are often used as technical measures for protection from flash floods. They are either used as independent structures or a multi structured system. The more complex the system, the more complicated is the identification of relevant precipitations providing a critical discharge on the downstream area, mostly directed towards determination of flood risks. One of the key elements is the correctly developed simulation model giving precise forecast of oncoming water wave. The paper reports on the risk determination method associated with rainfall probability. For an analysis the example of the complex Medvescak brook catchement was taken, as a part of Medvednica hill’ s water drainage system for protection of the city of Zagreb from floods. The simulation of oncoming water wave was conducted with hydraulic and hydrologic model, using HEC ("Hydrologic Engineering Centre") of the programme package, developed by the US Army Corps of Engineers hydraulic engineering centre. The model examines directly the output results’ sensitivity (transformation of water waves of different return periods) to the set of hydraulic catchement parameters (various precipitation cases with corresponding return periods and intensities - ITP curves). The maximal discharge, return period and rain period dependence diagrams were created to estimate flood risks: Qmaks – PP - Tk for characteristic catchement points. For these points, with regard to the bed capacity a water wave return period that does not overflow the bed was determined. The obtained results of the simulation model indicate that a satisfyingly constructed retention system provides a highquality flood protection for the observed area of Medvescak.

<p>This paper presents the concept of the project “Advanced monitoring of soil salinization risk in the Neretva Delta agroecosystem” (Delta Sal). Aim of the project is to develop and implement an advanced system for monitoring, forecasting and reporting the water and soil conditions in the Neretva Delta agroecosystem that is primarily used for agriculture. Selected pilot location is specific due to its biodiversity – water network within the delta consists of surface irrigation and drainage canal network, carst aquifer dominated by the tidal regime while also replenished by the freshwater from the upstream river flow, all of which are used for citrus fruits production while at the same time influencing the water regime of adjacent protected salt marshes ecosystem. Neretva Delta is dominated by the traditional farming methods practiced in the polder systems. Salt water intrusion is present in the entire delta, which is reflecting on the irrigation water quality and subsequently on the agricultural production of citruses that are salt-sensitive horticultural crops. Extensive spatial and temporal monitoring of water quality data through multisensory monitoring stations will be used for development of guidelines for salt stress alleviation in citrus fruits. This paper presents the outline of the project, methodology of analysis and selection of representative agricultural parcels for the research, rationale of farmer’s current decision-making that affects the agricultural landscape pattern and proposed monitoring network. Monitoring is focused on continuous real-time measurements of surface water levels and index water velocity using radars, shallow and deep piezometers for monitoring of ground water levels, rain gauges, multiparameter water quality measurements (dissolved oxygen, water depth, electrical conductivity, total dissolved solids, salinity, pH, oxidation reduction potential, temperature, nitrate and chloride). Data is transmitted in real-time to the cloud-based interface for remote access. Integrated data management will be used in the upcoming project stages for analysis of salt water intrusion on Neretva Delta agricultural production. Final outcome of the project are guidelines for Neretva Delta management with the future outlook in the climate change context, compliant with UNFCCC convention under which this area falls into one of the most vulnerable areas in Croatia.</p><p> </p><p>Acknowledgment:</p><p>„This work has been supported in part by the European Regional Development Fund under the project Advanced monitoring of soil salinization risk in the Neretva Delta agroecosystem (KK.05.1.1.02.0011)“</p>