Regular monitoring of water quality of the Danube river in the backwater zone includes analysis of the sediment. It is well known that sediment is a sink place for the non degradable compounds and it reveales the long term water quality status in the reservoir. This paper presents the general results on the Iron Gate reservoir siltation. as well as some data regarding pollution level, based on investigations carried in the period of 2001-2002. The investigations included organic load of the sediment, heavy metals and organic pollutants content. The degree of pollution is evaluated on the basis of various criteria, also compared to results of previous case studies.

The paper presents theoretical model of the pollutant density changes in water environment. Spreading of the pollutant is modeled by strong pointed force on the pollution system in the water. This force appears as a strong short term pressure in certain point of the system after which it starts to move in one direction. Results of applying of this model shows that density of the pollution depends on mass of the pollution and the speed of the spreading of the pollutant in the aquatic system. One dimensional result of the pollutant density that is received, i.e. pointed direction of the pollutant stands only in the cases of precisely fixed conditions defined by modeling. For any other values that exceed these values the pollutant density value is equivalent zero value.

During 2003 the referent monitoring of chemical quality of surface waters and sediments in Vojvodina (Serbia, Serbia and Montenegro) was conducted as a supplement to the regular monitoring program in Vojvodina. The aim of the study was to establish the chemical quality of surface waters and sediments. It is concluded that the water quality satisfies the criteria of the 1st/2nd class according to our legislation, with the exception of a few monitoring stations which showed a slight contamination with mineral oils and polycyclic aromatic hydrocarbons (PAHs)/ With regard to contamination of sediments with PAHs, organochlorine pesticides and polychlorinated biphenyls (PCBs) the Begej-Klek monitoring station may be considered as potentially problematic as the reference values according to Dutch legislation were exceeded for three classes of pollutants.

In this paper are represented the results of the pollution character of soils and water during the 2002. Taking into consideration the changes of analyzed parameters in during the analyzed period, there have been noticed strong periodical pollutions by organic substances, nutrients and industrial polluters with the growing tendency regarding frequency which make worse the quality of soil-water the drainage basin of the river Tara, unique in Europe is proposed. That is the reason why the monitoring of the mentioned potential, with support of the space informatics technology as the prerequisite of its management.