1. Library reserve packet:
The physical and chemical properties of seawater and of estuarine water are of course important determinants of the nature of the estuarine ecosystem. Some of these properties also affect circulation patterns and patterns of sediment deposition. For this reason we address this topic before we begin to discuss estuarine circulation patterns.
The first reading, from the oceanography textbook by Gross, considers basic characteristics of the water molecule and their influence on the physical properties of water. The composition of sea salt and the nature of salinity is then discussed, along with a treatment of the relationship between salinity, temperature, and density. Important aspects of seawater chemistry include the definitions of conservative and nonconservative properties; a brief reference to the biological importance of osmotic pressure; the solubility of gases as a function of temperature and salinity; and the carbon dioxide and carbonate cycles, which are also related to pH.
The reading from Kennish supplements these topics with some additional information on temperature, light penetration in water, salinity and major dissolved consituents in seawaer, pH, Eh (redox potential), description of conservative and nonconservative behavior in mixing of fresh water and seawater, and the roles of oxygen and carbon dioxide in estuarine waters.
A critical topic that we will not consider here is the dynamics of nutrient cycling, photosynthesis, respiration, and depletion of dissolved oxygen. This will be dealt with a little bit later in the semester as we begin to discuss estuarine ecology.