Sadbera Trožić-Borovac, Mahir Gajević, Aldijana Mušović, Senad Šljuka
ASSESSMENT OF THE AQUACULTURE IMPACT ON THE ECOLOGICAL POTENTIAL OF THE SALAKOVAC RESERVOIR (NERETVA RIVER)
DOI: 10.35666/28310438.2025.6.188
UDC: 502.131.1:556(497.6Salakovac)"2008/2021"
According to the Management plan for the water area of the Adriatic Sea in the territory of the Federation of Bosnia and Herzegovina, the Salakovac reservoir on the Neretva River belongs to type 13, which includes large lowland waterways. The mentioned reservoir is designated as a heavily altered water body. Within the Water Framework Directive, aquaculture is recognized as a pressure on water bodies, through the intake of nutrients, water pollution, introduction of non-native species, introduction of parasites and one of the ways of introduction of invasive aquatic species. The Salakovac reservoir has a total volume of 68x106 m3 and was created by the construction of a 70 meters high concrete gravity dam in 1981, located on the Neretva River, in the Salakovac settlement (15 km upstream from Mostar). It flows through the canyon section of the Neretva River (20 km long), built of carbonates of Mesozoic age with deposits of diluvial formations of fluvial origin, the left bank is made of limestone, while the right bank is made of dolomite. The work is the result of research (period from 2008 to 2021) as part of biomonitoring and the Aquaculture Study itself in the water area of the Adriatic Sea of FBiH (period from 2008 to 2021). For the purposes of the analysis, measurements of physicochemical parameters were performed with an emphasis on total chlorophyll a, TP and transparency (m). The Trophic State Index (TSI) was used to assess trophicity. In the assessment of the impact of aquaculture, the burden of pollution is indicated through the values of BOD5, TP and TN, as well as the values of nutrients in the sludge upstream and downstream of the fish farm. 8 fish farms with an average of 40 cages were installed on the reservoir. The first fish farm was installed in 1987. The obtained values indicate an increase in the value of trophicity (TSI = 51.381), and especially the concentration of nutrients in the sludge downstream of the cage breeding pond (TP = 1309 mg/kg). As a result of the introduction of ichthyo populations into cages in the period 2016-2019, non-native invasive species Dreissena polymorpha (Pallas, 1771) and Craspedacusta sowerbii Lankester, 1880 were identified. The trend of degradation continued with the increase of legal and illegal aquaculture facilities.
Keywords: protection, management, degradation, invasive species, control.