Variability in Dissolved Oxygen and Other Water-Quality Variables Within the National Estuarine Research Reserve System

• DOI: 10.2112/si45-017.1
• Publication Date: 2010-09-22T22:06:38Z
• Authors: Elizabeth Wenner; Denise Sanger; Michael Arendt; A. Frederick Holland; Yian Chen
• Keywords: 0106 biological sciences; 14. Life underwater; 15. Life on land; 01 natural sciences; 6. Clean water

Abstract Shallow estuarine habitats are normally characterized by wide interannual and intraannual fluctuations in water-quality variables, including dissolved oxygen; however, the short-term variability in water-quality variables is seldom measured and characterized. Water-quality data collected semicontinuously by automated data sondes from 1995 to 2000 at 55 sites among 22 National Estuarine Research Reserves (NERR) were analyzed to characterize temporal variability and compare conditions among estuarine systems and regions. Three-way analysis of variance (ANOVA) models revealed several significant interannual and seasonal differences for water-quality variables for many sites sampled within a reserve; however, interannual trends with respect to reserve or region were not readily apparent. Salinity and hypoxic events (dissolved oxygen [DO] < 28% saturation [sat]) were generally greatest in summer or fall. Evapotranspiration and precipitation appeared to influence seasonal salinity patterns at reserve s...