Seasonal Changes in Microbial Processes in Estuarine and Continental Shelf Waters of the South-eastern U.S.A.

The Effects of System-Level Nutrient Enrichment on Bacterioplankton Production in a Tidally-Influenced Estuary**

“…Asymptotic temperature responses of BP have recently been reported in estuaries (APPLE, DEL GIORGIO, and KEMP, 2006;MURRELL, 2003) and lakes (FELIP, PACE, and COLE, 1996), which may drive the relationship between temperature and BP : CHLA values. The positive temperature response of BP : CHLA is also in general agreement with the strong temperature dependence of heterotrophic relative to autotrophic microbial processes in a range of estuarine ecosystems (HOCH and KIRCHMAN, 1993;POMEROY et al, 2000;SAMPOU and KEMP, 1994;SHIAH and DUCKLOW, 1997) and the weakened coupling of BP and CHLA (i.e., lower BP per unit CHLA) observed at lower temperatures (HOCH and KIRCHMAN, 1993;SHIAH and DUCKLOW, 1994a).…”

“…The covariation of BP to algal biomass can be influenced by temporal lags between primary production and availability of algal substrates for consumption by bacterioplankton (BILLEN, 1990), reliance of BP on nonalgal substrates (BAINES and PACE, 1991; BANO, MORAN, and HOD-SON, 1997), differences in extracellular organic carbon release per unit primary production (BAINES and PACE, 1991), and direct (and disproportional relative to phytoplankton) effect of nutrients on bacterioplankton production (VREDE et al, 1999). Coherence between BP and CHLA may also be undermined by variability in bacterial growth efficiency (DEL GIORGIO and COLE, 1998), high turbidity (POMEROY et al, 2000), allochthonous inputs of organic matter (HOCH and KIRCHMAN, 1993;REVILLA et al, 2000), and disproportionate effect of temperature on bacteria relative to phytoplankton (SHIAH and DUCKLOW, 1994a). The extent to which measurements of CHLA accurately represent in situ algal biomass and production may also be compromised by variability in the carbon-to-chlorophyll ratio of phytoplankton (CLOERN, Journal of Coastal Research, Special Issue No.…”

Air–sea exchanges of CO<sub>2</sub> in the world's coastal seas

“…Riverine organic carbon is supplied primarily by the erosion of soil organic matter or plant detritus (allochthonous) and by phytoplankton in water (autochthonous). The inorganic carbon is derived mainly from soil and rock erosion, and by the oxidation of organic matter mostly through microbial processes (Odum and Hoskin, 1958;Odum and Wilson, 1962;Probst et al, 1994;Neal et al, 1998;Nelson et al, 1999;Pomeroy et al, 2000). These organic and inorganic forms of carbon in dissolved and particulate phases reach the estuaries, which are typically wider than river channels.…”

The role of marsh‐dominated heterotrophic continental margins in transport of CO2 between the atmosphere, the land‐sea interface and the ocean

“…The SAB is also bounded by the Gulf Stream along its shelf break which is only 70 m in depth. Extensive biological and physical oceanographic studies have been conducted in the SAB [Menzel, 1993;Pomeroy et al, 2000]. The shelf has no annual spring bloom and the episodic intrusion of the nutrient-rich Gulf Stream water is the driving force for biological production on the shelf.…”