Diversity of Aquatic Macroinvertebrates in Streams in the Belgrade Region (Does Different Stream Types Matter?) - page 2

In total, only five taxa were present in all the stream types. Besides Nematoda and Chironomidae, tubificid worms Limnodrilus hoffmeisteri and Potamothrix hammoniensis, and snail Physella acuta were common for analyzed stream types (Table 2). Tubificids L. claparedeanus Ratzel 1868 and L. udekemianus Claparede, 1862 as well as biting midges (Ceratopogonidae), were present in all stream types, except in Type 6, i.e. the type with the lowest overall diversity (Table 2).

A relatively low number of common taxa among the analyzed types could suggest noticeable faunistical differences. However, the performed multivariate analysis (DCA) does not provide support for the above mentioned, as the obtained biplot reveals overlapping of samples belonging to different stream types (Figure 2). However, some differences, regarding localities could be noted along the first DCA axys, particularly between the Danube Batajnica locality (1) on the left side, and the Kotež -Vizelj locality (19) on the right. The separation arises primarily due to the presence of taxa Psammoryctides barbatus (Grube, 1861) (code Psa bar), Isochaetides michaelseni Lastockin, 1936) (Iso mic) and Corophium curvispinum (Sars,1895) (Cor cur) in the first locality, i.e. due to the presence of Eiseniella tetraedra (Savigny, 1826) (Eis tet), Dugesia lugubris Schmidt, 1861 (Dug), Alboglossiphonia heteroclita (Linnaeus, 1758) (Alb), Bythinia tentaculata (Linnaeus, 1758) (Byt), Sympetrum sp. (Sym) and Caenis horaria (Linnaeus, 1758) (Cae hor) in the second (Vizelj-Kotež).

The performed multivariate analysis could not separate watercourses in the Belgrade Region, in regards to the corresponding types. As the main reason behind the revealed uniformity could be urbanization and other anthropogenic activities, resulting in a reduction in the number of less tolerant taxa, together with an increase in the diversity and significance of pollution-tolerant taxa (Walsh et al., 2005; Smith and Lamp, 2008). A faunistic shift is noticeable in the overall diversity of the main taxonomic groups, with Oligochaeta (ie tubificids) as the most diverse members of the macroinvertebrate community in all the analyzed types of watercourses. The performed ecological assessment analysis (Kračun et al., 2013) showed poor overall ecological status/potential of these urban watercourses, indicating deteriorated habitats and communities.

However, it should be pointed out that the number of analyzed samples/watercourses is limited, especially in the case of types 2 and 6 (only two each), which could be the reason for its lower general diversity, compared to the other types. For more reliable analysis, prolonged and more detailed sampling is needed.

 

Acknowledgments

This study was supported by the Institute of Public Health Belgrade.

 

Fig02

Figure 2: DCA performed on the 21 sample x 65 taxa data matrix (presence/absence); localities and taxa codes are provided in Tables 1 and 2, respectively.