Vergleich der Zuckmücken-Besiedlung bodenwasser-gespeister und straßenabwasser-belasteter Bachläufe (Diptera: Cbironomidae)
[Comparison of Chironomid Coenoses of Soilwater-fed and Municipal Surfacewater-affected Streams (Diptera : Chironomidae)]
Mölleken, Helga M.; Steffan, Wilhelm
Distribution and abundance of Chironomidae in 5 urban brooks of the Niederberg Region (NW'Germany) are investigated in comparison with the situation in natural or nearly natural brooks of that area. At 19 sampling stations only 22 species were found in total. This is considered to depend primarily upon the physiographic instability of these running waters, as they are principally fed by soilwater. The successive reduction of Chironomidae in number of species and abundance of individuals can be traced back to the influence of organic and inorganic materials supplied by polluted municipal surface-water. The physiographical conditions are found to be basic for the qualitative as well as for the quantitative differences between the compared Chironomidae coenoses of these brooks.