Physical, chemical and faunal characteristics of a perennial stream in arid northern Oman

A study of a 1•5 km stretch of a perennial stream in arid northern Oman describes the physical, chemical and faunal characteristics of riffles, runs and pools. Air temperature seems to influence invertebrate recruitment. Flooding is the most important catastrophic event that alters the physical and chemical environment. Current velocity and substrate composition are also probable factors affecting the community structure. All other chemical conditions except nitrate (–N) were significantly similar in all biotopes. Three vertebrate and 33 invertebrate taxa were recorded. The low faunal diversity is a reflection of a physically controlled system.