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Southeast Stream Quality Assessment


The Southeast Stream Quality Assessment (SESQA) study characterized watershed and water quality parameters, with the goal of determining the factors that have the greatest potential to alter biotic condition across the southeast.


Odontidium | Amphora bicapitata | Aneumastus carolinianus | Encyonema minutum var. pseudogracilis | Encyonema pergracile | Encyonema reichardtii | Fallacia subhamulata | Fallacia vitrea | Fragilariforma marylandica | Grunowia solgensis | Halamphora latecostata | Hippodonta pseudacceptata | Luticola minor | Luticola mobiliensis | Navicula genovefae | Navicula ingenua | Navicula kotschyi | Nitzschia angustata | Odontidium hyemale | Odontidium mesodon | Placoneis anglophila | Prestauroneis protracta | Pseudofallacia monoculata | Sellaphora stauroneioides | Stauroneis smithii var. incisa | Synedra goulardi | Tetracyclus rupestris | Ulnaria contracta |


Design and methods of the SESQA Survey
The Southeast Stream Quality Assessment


Species composition and abundance of diatoms in streams and rivers are a crucial measure of biotic condition as diatoms are sensitive to impacts caused by human activities such as urbanization, flow alteration, and the loading of contaminants, nutrients and sediment. Regional surveys of rivers by the U.S. Geological Survey
(USGS) National Water Quality Assessment Program (NAWQA) were designed to evaluate the effects of these stressors on aquatic organisms, including diatoms.

Algal samples were collected at 108 sites in 2014, from streams representing gradients in chemical and physical alteration across the southeast region. More than 375 taxa were identified during analysis for species composition and abundance. A flora of diatoms in the region was published:

Bishop, I.W., Esposito, R.M., Tyree, M. and Spaulding, S.A. 2017. A diatom voucher flora from selected southeast rivers (USA). Phytotaxa, (in press).

A number of taxon pages were developed based on this material. In addition, a workshop on species of Gomphonema was based primarily on specimens from the southeast.


US Geological Survey

Rocky Mountain Cooperative Ecosystem Study Unit (CESU) Agreement G15AC00104 | Diane McKnight


Ian Bishop

Graduate Student, Graduate School of Oceanography, University of Rhode Island
Review Board, This Website

Meredith Tyree

Professional Research Associate, Institute of Arctic and Alpine Research, University of Colorado

Sarah Spaulding

Ecologist, US Geological Survey
Review Board, This Website

Rhea Esposito

Cary Institute of Ecosystem Studies

Alec Camp

University of Colorado

Paul Bliznik

University of Colorado

Leanna Jo Clarkson

University of Colorado

Tanya Hannis

University of Colorado

This project was first entered on 27 November, 2017 by Sarah Spaulding