may be increased. Laguna Madre during the 1990s provides an example of an ecosystem with 
small nutrient loading that developed symptoms of eutrophication. An inedible phytoplankton 
spQcxQS Aureoumbra lagunensis developed into a brown-tide bloom because most consumers 
could not ingest it. Those that could were being controlled by predators. Because of the 
mechanism by which this bloom developed, it could not be predicted easily by regression. 
However, susceptibility to such blooms could be predicted by food web models. 
2. Food web models can be used to calculate the dependency of charismatic and recreational 
species on other components of the food web, and how such dependency would be altered by 
changes in nutrient loading. This knowledge would arm managers with a eariy warning system 
to detect alterations in an ecosystem that eventually could lead to reductions or decreased 
production of important species. 
Each of these modeling strategies has different data requirements and makes predictions at 
different temporal and spatial scales. We will integrate the three approaches by working 
cooperatively to maximize the benefits of the approaches and minimize the limitations. The final 
outcome of this research implementation plan will be a set of empirical or numerical models for 
classes of coastal waters. These models will be able to accurately describe how increases in 
nutrient loading causes changes in hypoxia/anoxia in coastal receiving waters, losses of SAV, 
and changes in algal community composition leading to shifts in basic food webs. The models 
will provide the scientific basis for the development of nutrient criteria for coastal receiving 
waters. We should be able to extrapolate results between similar classes of receiving waters 
once a classification scheme incorporating key factors affecting nutrient response for coastal 
receiving waters is developed and tested. 
NHEERL Ecology Divisions are strategically located in four major coastal systems with AED 
along the Atlantic Coast, GED on the Gulf Of Mexico, WED along the Pacific Coast, and MED 
on the Great Lakes. Each of these Divisions will focus intensive studies on a local system and 
collect pertinent related information from other systems in their general region. All four 
Divisions will work to develop a common approach for key parameters and measurements that 
are needed across all regions (i.e., what, when, where, and how for nutrient loading, DO, 
Chlorophyll a) and maintain that approach through annual reviews. Other measurements (e.g., 
community metrics or depth of oxygen penetration into sediment) may be developed within or 
compared across multiple regions as individual Divisional research plans are developed further. 
Research Projects 
Project Title 1. Development of nutrient load-DO Response Relationships for Coastal 
Receiving Waters 
Project Coordination and Resources (9.0 FTEs: AED-4.0, GED-3.0, MED-1.0, WED-l.O) 
49 
