Macrozoobenthos as an determinant of ecological status of the bosna river

UDK: 574.587(282.249 Bosna) The paper presents the distribution and diversity of macrozoobenthos composition of Bosna river up to Zenica, from 1999 to 2010. Macrozoobenthos has been chosen as an element of bioevaluation of the ecological state of running water, and according to the provisions of the Water Framework Directive. Sampling has been done by using the kick-sampling amd multihabitat method, a standard for hydrobiological research. The highest diversity of macrozoobenthos has been found in samples from the sites Rimski most (36 taxa), and the lowest was at site of the Bosna River upstream from the mouth of Ljubina river and downstream of the mouth of the Zgošća river (4 taxa). According to abiotic conditions which directly affect the composition of macrozoobenthos, and using Bray-Curtis similarity, the highest degree of similarity has been found in sites which are spatially nearby. Taxa number and EPT taxa number were highly correlated (R2 = 0,871). Saprobic index and BMWP index were calculated in assessing the ecological status of the river Bosna at the study sites. The values obtained comparing EPT taxa number and BMWP index show a high correlation (R2 = 0,706). The composition and the distribution of the macrozoobenthos in the Bosna river are conditioned by abiotic parameters. Sites upstream of the mouth of the Ljubina river and downstream from the mouth of the Zgošća river represent the places with the highest pollution which is the result of point and diffuse sources of pollution.