Synergy of light and nutrients on the photosynthetic efficiency of phytoplankton populations from the Neuse River Estuary, North Carolina (original) (raw)

2002, Journal of Plankton Research

Estuarine phytoplankton are subject to many interacting and competing stressors and they must compete for available resources to maximize their photosynthetic rates and growth (Petersen et al., 1997). Characterizing the physiological response of phytoplankton to interacting environmental variables is essential to anticipating changes that might occur due to anthropogenic disturbances. This is fundamental to the formation of effective coastal nutrient management practices (Cloern, 1996). These humaninduced impacts include enhanced nutrient loading (Hobbie and Smith, 1975; Paerl et al., 1995), modified nutrient ratios (Quian et al., 2000), altered flow regimes (Rudek et al., 1991), and enhanced ultraviolet (UV) radiation (Hader and Worrest, 1991). Given this, developing a non-intrusive means to characterize the physiological state of phytoplankton communities and to predict their response to interacting anthropogenic disturbances has long been a goal of environmental scientists. Work over the last two decades by plant scientists and oceanographers (Kolber et al., 1988; Schreiber et al., 1995) has demonstrated the utility of chlorophyll a (chl a) fluorescence measurements as a sensitive indicator of the physiological state of phytoplankton populations under erratic conditions.