Hyporheic fauna from interstitial of the Someş River basin (Transylvania, northwestern Romania)

• Main Authors: Claudia Pavelescu, Mirela Cîmpean, Ioana Meleg
• Format: Article
• Language: English
• Published: Editura Academiei Romane 2009-01-01
• Series: Travaux de l'Institut de Speologie Emile Racovitza
• Subjects: hyporheic communities; interstitial; water mites; cyclopoids; oligochaetes; biodiversity; statistical analyses
• Online Access: http://www.speotravaux.iser.ro/09/art04.pdf

Biodiversity in hyporheic habitats (interstitial water habitats in river bank sediments) has been studied on Someşul Cald (Warm Someş) and Someşul Rece (Cold Someş) River (north-western Romania, Transylvania), from March to October 2004. pH and electrical conductivity were measured monthly at each site, and animals were collected with the Karaman-Chappuis method and by filtering water through a hand-net. The relative abundance of the best-represented hyporheic invertebrates (oligochaetes and insect larvae) was higher in Someşul Cald interstitial habitats than in Someşul Rece. The focus was directed to the role of water mites (Acari, Hydrachnidia), cyclopoid copepods (Crustacea, Copepoda, Cyclopoida) and oligochaetes (Annelida, Oligochaeta) in hyporheic communities. Nine water mites and five cyclopoid species were identified in five sampling sites of the two rivers. Their higher diversity was recorded in two stations on the Someşul Cald River. The cyclopoid copepod Diacyclops disjunctus (Thallwitz, 1927) is a new record for Romania. As for oligochaetes, 17 species were identified and their higher diversity was recorded on Someşul Rece River. Canonical Correspondence Analysis (CCA) shows that presence of some water mites and cyclopoid species can be associated with measured physicochemical parameters (pH, electrical conductivity). Principal Component Analysis (PCA) shows similarities between stations and the dominant taxa in some samples.