Offshore Oceanographic and Environmental Monitoring Services for the Strategic Petroleum Reserve - Response to Decision Maker's Questions: Benthos - FINAL

The seemingly infinite capacity of the oceans to absorb and hide refuse has been used by man to dispose of all manner of material for thousands of years. Most of this material was relatively innocuous and there was not resulting "back-lash". However, with the advent of the industrial revolution, more and more of the substances produced by man, particularly by the chemical industry, were toxic to some degree. It is no longer feasible to simply "dump" byproducts, wastes, and other cast-off material into the ocean and pretend they no longer exist. This is proved by the mercury poisoning incident in Minimiata, Japan, the uproar over incineration of chemicals at sea, disposal of petrochemical products into shallow waters and the furor that was generated when the Strategic Petroleum Reserve brine disposal array was first proposed, to name a few examples. Brine is probably among the least toxic substances being disposed in the oceans. In narrow bayous and streams, brine can form a dense bottom layer whose salinity exceeds the tolerance ability of many benthic invertebrates and nektonic organisms (Harper, in prep.). In the oceanic environment, brine is not restricted and can speard and flow with the prevailing currents. Potential problems associated with brine are: 1) increased salinity from incomplete mixing which not only covers the bottom, but percolates into the sediments; and 2) an ionic ratio that is different from sea water and may cause ionic imbalance in soft bodied organisms that do not have the ability to regulate their internal osmotic concentration. Any given benthic assemblage is not a static entity. The components of the assemblage are constantly shifting as new members are recruited and existing members are removed by death or in some cases migration. Death can be caused by a number of agents, i.e. predation, old age, abiotic stress (high or low temperature, anoxia, salinity changes) and introduction of toxic substances. To be capable of making decisions concerning disposal of substances in the ocean, one must be capable of distinguishing between natural death and toxic-induced death. And to obtain this capability, one must know how much variability exists in the natural community.