dc.description.abstract | This thesis study was conducted on Sarıçay, Karamenderes, Tuzla and Kocaba? Streams located on Biga Peninsula in order to reveal the seasonal distributions and community structures of Oligochaeta (Annelida) and Chironomidae (Diptera) fauna in relation to some environmental variables between Autumn 2008 and Summer 2009. The data, comprising the zoobenthos records and environmental variables collected from 15 sampling stations on the Biga Peninsula Streams were subjected to multi dimensional techniques.Environmental variables such as temperature, salinity, pH, electrical conductivity, TDS mgL-1 and dissolved oxygen were measured in situ by using YSI 100 portable probe, simultaneously with benthic sampling. In addition, Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Ortho-Phosphate (PO4-P), Nitrate Nitrogen (NO3-N), Total Suspended Solids (TSS) and Turbidity were analyzed by classic, colorimetric, cadmium reduction, filtration and nephelometric methods based on USEPA, 1998 respectively. Moreover, the texture and some variables such as pH and conductivity were also analyzed in stream bed sediment by hydrometric and electrometric methods based on, respectively.According to the data, 33 Oligochaeta and 87 Chironomidae taxon have been identified in 15 stations of the studied streams. The Naididae was the richest family of the Oligochaeta fauna in the study area represented by 29 taxa, followed by Enchytraeidae (2 taxa) and Lumbriculidae (2 taxa). The streams could be listed as follows according to the species richness of Oligochaeta;, Tuzla (27 taxa), Karamenderes (21 taxa), Sarıçay (20 taxa) and Kocaba? Stream (17 taxa). The Chironominae was the highest species diversity among Chironomidae family with 38 taxa (27 of Chironomini and 11 of Tanytarsini tribes), followed by Orthocladiinae with 32 taxa, Tanypodinae with 14 taxa, Diamesinae with 2 taxa and Prodiamisinae with 1 taxa of the Diptera larvae were determined. The studied streams could be listed according to the species richness of Chironomidae as follows; Kocaba? Stream (66 taxa), Karamenderes (65 taxa), Tuzla (57 taxa) and Sarıçay (46 taxa).In the study area, the relationships between Oligochaeta and Chironomidae fauna and environmental variables were revealed by Multi Dimensional Scaling Analysis (MDS). Individual numbers of the species from different habitats of all the station were subjected to Multiple Correspondence Analysis (MC) and Cluster Analyze. As a result of the analysis, it was determined that the species were distributed along the stream by their ecological requirements.It was determined that tolerant species to pollution of Oligochaeta and Chironomidae were dominated at the streams in the sampling area.The Bothrioneurum vejdovskyanum Stolc, 1886, Mesenchytraeus sanguineus Nielsen & Christensen, 1959 and Enchytraeus christenseni Dozsa-Farkas, 1992 were the first records for Oligochaeta fauna of Turkey.Key Words: Oligochaeta, Chironomidae, Sarıçay, Karamenderes Stream, Tuzla Stream, Kocabaş Stream, Environmental Variables. | en_US |