A Classification of U.S. Estuaries Based on Physical and Hydrologic Attributes

Abstract

A classification of U.S. estuaries is presented based on estuarine characteristics that have been identified as important for quantifying stressor-response relationships in coastal systems. Estuaries within a class have similar physical and hydrologic characteristics and would be expected to demonstrate similar biological responses to stressor loads from the adjacent watersheds. Nine classes of estuaries were identified by applying cluster analysis to a database for 138 U.S. estuarine drainage areas. The database included physical measures of estuarine areas, depth and volume, as well as hydrologic parameters (i.e., tide height, tidal prism volume, freshwater inflow rates, salinity, and temperature). The ability of an estuary to dilute or flush pollutants can be estimated using physical and hydrologic properties such as volume, bathymetry, freshwater inflow and tidal exchange rates which influence residence time and affect pollutant loading rates. Thus, physical and hydrologic characteristics can be used to estimate the susceptibility of estuaries to pollutant effects. This classification of estuaries can be used by natural resource managers to describe and inventory coastal systems, understand stressor impacts, predict which systems are most sensitive to stressors, and manage and protect coastal resources.

Fish under influence: A macroecological analysis of relations between fish species richness and environmental gradients among European tidal estuaries

“…For instance, annual or seasonal temperature and rainfall data could represent useful information on the influence of climatic conditions upon a catchment area (Pease, 1999;Ley, 2005;Engle et al, 2007). Biological production (Willig et al, 2003) within an estuary and on the adjacent coast and shelf, and for instance the presence of upwelling fronts known to modulate the production and distribution regimes of marine species (e.g.…”

“…residence time) that influence rates of sediment flushing (Engle et al, 2007). Estuarine hydrodynamics are under larger scale control, mainly estuary geomorphology, climate (e.g.…”

“…Main features of estuaries thus strongly influence fish habitats and communities at different scales (Roy et al, 2001;Saintilan, 2004;Harrison and Whitfield, 2006). Consequently, taking into account the large-scale driving factors (Keddy, 1992), macroscopic studies of the relationships between environment and fish assemblage structure may help, first, to understand the functioning of estuarine ecosystems, and then, to assess their ecological status so that appropriate management decisions can be taken (Brown, 1995;Peterson, 2003;Engle et al, 2007).…”

Cumulative Effects of Coastal Habitat Alterations on Fishery Resources: toward Prediction at Regional Scales

“…Nevertheless, it is encouraging for future studies that independent estimates of prerecruit survival from Alabama and Mississippi were equivalent. A more detailed model would benefit from large-scale validation of these estimates and their variability for Gulf of Mexico estuaries or relevant classes of estuaries (Engle et al 2007). We extrapolated habitat effects on recruitment from Mobile Bay to the U.S. Gulf-wide crab stock, thereby introducing potentially large uncertainty.…”

Caracterizacion hidrografica del estuario del rio Valdivia, centro sur de Chile

“…Si bien ningún estuario es igual a otro, la definición de patrones generales de su dinámica es útil para comprender las diferencias y similitudes entre los cientos de estuarios, identificar y priorizar esfuerzos de conservación de los servicios ecosistémicos, manejo de recursos y guía para futuras investigaciones (Engle et al, 2007). Además, la estratificación estuarina es importante porque inhibe la mezcla vertical, que afecta la dinámica de la columna de agua y podría conducir a la hipoxia en las aguas debajo de la picnoclina (Geyer, 2010).…”