Primary estuaries

Primary estuaries are formed from terrestrial and/or tectonic processes with minimal changes from the sea—these systems have essentially preserved their original... 

Jassby AD, Cloem JE, Cole BE (2002) Annual primary production patterns and mechanisms of change in a nutrient-rich tidal estuary. Limnol Oceanogr 47 698-712... 

Table 2. Known inputs and outputs of U to the oceans. Units are 10 g yr or thousand tons per year. References are the most recent primary studies of that flux. Some other fluxes (e.g., groundwater input and input or removal at estuaries) are so poorly known that they cannot be realistically included. Significant uncertainty remains in most of the fluxes listed above so that, within these uncertainties, the U budget can be considered to be in balance.

Static die-away tests were performed by Potter et al. with an A9PEO7 24 mixture in water from a vertically well-mixed estuary in Florida [36]. Lag times of 0—12 days were observed, and after 4—24 days, primary degradation was complete. These rates are similar to those reported by Kvestak and Ahel [6]. It is likely that the microorganisms in these experiments were pre-acclimated to biodegrade nonionic surfactants, as a municipal sewage treatment plant discharge is present a few kilometres upstream. 

Nitrogen pollution has received far more attention than that of phosphorus for two reasons. First, it has been considered as the nutrient-limiting primary production in estuaries and coastal waters. Second, its loading into the coastal zone has been far greater than that of phosphorus (Figure 24.21). It is also more efficiently exported into the ocean due in part to formation of iron phosphate minerals in anoxic estuarine sediments. 

Moreover, both river induced up-welling and river discharge of nutrients create a fertile environment which enhances the primary production of organic matter in off-shore direction of estuaries. It can be predicted from these observations that heterogeneous reactions between dissolved and both mineral phase and biota will be predominant in estuaries and coastal zones. These reactions will primarily affect those elements and compounds which are located at the particulate surface. The determination of surface properties of particles appear to be an important key to understand the interactions of trace elements and organic compounds between particulate and dissolved phases in estuarine and coastal systems. 

This major input of DOM from macrophytes is not restricted to lakes, but is also realized in other aquatic ecosystems. DOM export from watersheds in lotic ecosystems is directly related to annual runoff, but significantly greater in swamp-draining streams compared with upland-draining streams (Mulholland and Kuenzler, 1979 see Chapter 2 and 6). In the Hudson Estuary, planktonic bacterial production is 3 to 6 times greater than primary production (Findlay et al., 1992). DOC derived from submerged aquatic plants in part supports the difference in bacterial carbon uptake and planktonic primary production. 

As for lakes, primary production in estuaries tends to be nutrient dependent and can vary with nutrient load from 30 to 1000 g C m 2yr 1 (Gilmartin, 1964 Cadee and Hegeman, 1974 Cadee, 1978, 1986 Sirois... 

Boyer, J. N., R. R. Christian, and D. W. Stanley. 1993. Patterns of phytoplankton primary productivity in the Neuse River estuary, North Carolina, USA. Marine Ecology Progress Series 97 287-297. 

Cadee, G. C. 1978. Primary production and chlorophyll in the Zaire River, estuary and plume. 

Fisher, T. R., P. R. Carlson, and R. T. Barber. 1982. Carbon and nitrogen primary productivity in three North Carolina estuaries. Estuarine, Coastal and Shelf Science 15 621—644. 

Randall, J. M., and J. W. Day, Jr. 1986. Effects of river discharge and vertical circulation on aquatic primary production in a turbid Louisiana (USA) estuary. Journal of Sea Research 21 231-242. 

Sirois, D. L., and S. W. Fredrick. 1978. Phytoplankton and primary production in the Lower Hudson River Estuary. Estuarine, Coastal and Shelf Science 7 413—423. 

Many of the previous morphological classifications of estuaries provided by Fairbridge (1980) and others fail to make any connection with the prior structure and relief in which an estuary has formed (Perillo, 1995). A more recent modification of this classification system uses an approach that better encompasses the spectrum and diversity of estuarine systems (figure 2.5 Perillo, 1995). It also provides a genetically based linkage of primary and secondary estuaries based on classification of the shoreline (see Shepard, 1973), which considers the prior structure from which an estuary has formed. This morphogenetic... 

As nonconservative gases, carbon dioxide and oxygen are closely coupled to the organic carbon pool through autotrophic (e.g., photosynthesis) and heterotrophic (e.g., respiration) processes. The dominant primary producers in estuaries and the coastal ocean are benthic and pelagic microalgae (phytoplankton). The average atomic C-to-N-to-P ratio... 

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