Diel variations in physical and chemical parameters in a semi-arid stream in Spain (Chicamo Stream)

Abstract

Rivers and streams fluctuate both spatially and temporally. Diel, seasonal and annual variations are well documented for temperate forest rivers (e.g. CHESTERIKOFF et al. 1991, REBSDORF et al. 1991), for desert streams and pools (e.g. SCHOLNICK 1994, JONES et al. 1995) and prairie streams (e.g. ZALE et al. 1989) but few data exist on diel variations in arid and semi-arid streams in the Mediterranean region (e.g. MARTI et al. 1994, GUASCH et al. 1998). However, these fluctuations are important for the aquatic community (e.g. JACKSON 1988) and may influence their life cycle. This study focused on diel variations in some physical and chemical parameters in a Mediterranean stream, as part of a major project, the principal objective of which was to examine some aspects of the metabolism of the Chicamo Stream, a semi-arid Mediterranean stream located in south-east Spain. The objectives of this study could be summarized as: (1) the analysis of diel variations of seven physico–chemical parameters in six sampling sites of the Chicamo Stream, during winter, spring, summer and autumn, and (2) a comparison of the seasonal and diel fluctuations with the variations obtained during an annual cycle.