SAVA

River Basin

The Sava River (945 km) is the major drainage basin of South Eastern Europe and the largest tributary to the Danube River. The 97,713.20 km2 large catchment is extended over Slovenia, Croatia, Bosnia and Herzegovina and Serbia.

Potential stressors

In the Alpine headwater regions mean annual precipitation range between 2000 and 3000 mm per year with a mean annual temperature of 6 °C. At the confluence of the Sava with the Danube, annual precipitation decreases sharply to around 660 mm per year and temperature increases to 13°C. The important characteristic of the Sava is its quick response to precipitation that is also reflected in the short mean residence time of approximately 2 years estimated in the river. The population in the Sava basin is about 8.2 million (46% of the total population of all the riparian countries). The basin is covered by forest and semi-natural areas (55%) and agricultural surfaces (42%). Sava provides drinking water (surface and groundwater) for the population in large cities. The upper reaches are largely influenced by carbonate mineral weathering, the middle by agricultural activity and biological processes related to eutrophication, while the lower reaches are influenced mostly by stressors related to high pollution from industrial processing along with untreated municipal waste water discharges.

Study area

Data on the environmental status of the Sava River are available through the national water monitoring programs. However, data gaps are obvious, since the most of the activities are limited to certain river sections, or to particular variables, and datasets are not entirely comparable. The data on temperature, discharge and water level are monitored continuously for at least 30 years (lately with automatic monitoring stations), while temperature data are available for about the last 100 to 150 years. Globaqua contributions to investigate the influence of multiple stressors on the water quality and quantity and to evaluate the impact of chemical pollution and other stressors on biodiversity; to determine transport and impact of pollutants under extreme hydrological events (floods and droughts); to study the appearance and distribution of invasive species in the basin; to assess change scenarios in the water resources ecosystem services and the effects in socio-economic development.

Contact person: Radmila Milacic (JSI), [email protected]