|
<br />OJn742
<br />
<br />"
<br />
<br />that biogeographical features (latitude, altitude, slope,
<br />distance from Pacific Ocean) and hydrological vari-
<br />ables (current velocity, mean depth) were most useful
<br />in delineating site groupings in a survey of streams
<br />in north-western North America, Within basins,
<br />Ormerod & Edwards (1987) determined that water
<br />chemistry (pH or total hardness) and associated geo-
<br />logy were the dominant correlates with macroinvert-
<br />ebrate assemblages, along with slope or distance from
<br />source in the River Wye, Richards et ai, (1993) reported
<br />that substrate variables were the most important fac-
<br />tors explaining variation in macroinvertebrate commu-
<br />nities in a Michigan agricultural watershed, As
<br />demonstrated by all these studies, the type of environ-
<br />mental factors affecting invertebrate community distri-
<br />bution in stream ecosystems differs based on the
<br />spatial scale (regional, basin, within stream) examined
<br />and the large-scale environmental gradients (e,g, alti-
<br />tude) present within the study area, For the South
<br />Platte River Basin, ecoregions and physical (geomor-
<br />phology) and chemical factors (as affected by land
<br />use) within ecoregions are dominant factors affecting
<br />invertebrate distribution.
<br />
<br />Acknowledgments
<br />
<br />"
<br />
<br />This study was supported by the US Geological
<br />Survey's National Water Quality Assessment Program:
<br />South Platte River Study, We thank KF. Dennehy, J,R
<br />Ortiz, RC. Averett, V. Averett, RC. Petersen, LR
<br />DeWeese, P,B. McMahon, D.W, Litke, J,E, Paschal, RB.
<br />Swanson, GD, McElhany, and KL Findell for field
<br />assistance, We thank H,V. Leland for assistance in data
<br />analyses, We thank H,V. Leland, KF. Dennehy, R,G,
<br />Smegl, T,M, Short and an anonymous referee for
<br />their critical review of the manuscript. This paper is
<br />dedicated to the memory of Robert C. Averett
<br />(deceased June 25, 1993) whose leadership in aquatic
<br />ecology and inspiration to aquatic ecologists will
<br />be missed,
<br />
<br />References
<br />
<br />Anderson JR, Hardy E,E" Roach J,T, & Witmer RE,
<br />(1976) A land use and land cover classification system
<br />for use with remote sensor data. U.S. Geological Survey
<br />Professional Paper 963, 28 p,
<br />Benke AC., Van Arsdall T,C., Gillespie D,M, & Parrish
<br />EK. (1984) Invertebrate productivity in a subtropical
<br />
<br />@ 1995 Blackwell Science Ltd, Freshwater Biology, 33, 439-454
<br />
<br />Invertebrates of the South Platte River 453
<br />
<br />blackwater river: the importance of habitat and life
<br />history, Ecological Monographs, 54, 25-<i3.
<br />Bruns DA & Minshall G,W (1985) River continuum
<br />relationships in an 8th-order river reach: analyses of
<br />polar ordination, functional groups, and organic matter
<br />parameters, Hydrobiologia, 127, 277-285,
<br />Bruns D,A, Hale A,S. & Minshall G,W (1987) Ecological
<br />correlates of species richness in three guilds of lotic
<br />macroinvertebrates, Journal Freshwater Ecology, 4, 163-
<br />177-
<br />Bruns DA, Minshall G,W, Brock j,T., Cushing c.E.,
<br />Cummins K,W, & Vannote RL. (1982) Ordination of
<br />functional groups and organic matter parameters from
<br />the Middle Fork of the Salmon River, Idaho, Freshwater
<br />Invertebrate Biology, 1, 2-12,
<br />Buchanan T.I, & Somers W,P, (1969) Discharge
<br />measurements at gaging stations. U.S. Geological Survey
<br />Techniques of Water Resources Investigations, Book 3,
<br />Chapter A8, 65 p, "
<br />Corkum L.D. (1989) Patterns of benthic invertebrate
<br />assemblages in rivers of northwestern North America.
<br />Freshwater Biology, 21, 191-205,
<br />Dennehy K.E, Litke D,W" Tate C.M. & Heiny j,S, (1993)
<br />South Platte River Basin-Colorado, Nebraska and
<br />Wyoming, Water Resources Bulletin, 29, 1-40,
<br />Eschner T.R, Hadley RE & Crowley K.D, (1983)
<br />Hydrologic and morphologic changes in channels of
<br />the Platte River Basin in Colorado, Wyoming, and
<br />Nebraska, A historical approach, V,S, Geological 5urvey
<br />Professional Paper 1277-A, 1-39,
<br />Fishman M.j, (1993) Methods of analysis by the V,S,
<br />Geological Survey National Water Quality
<br />Laboratory - determination of inorganic and organic
<br />constituents in water and fluvial sediments. U.S.
<br />Geological Survey Open File Report 93--125, 217 p,
<br />Folk RL. (1980) Petrology of Sedimentary Rocks, Hemphill,
<br />Austin, TX, 184 p,
<br />Furse M,T" Moss D., Wright J,F. & Armitage P.D, (1984)
<br />The influence of seasonal and taxonomic factors on the
<br />ordination and classification of runnj.ng-water sites in
<br />Great Britain and on the prediction of their macro-
<br />invertebrate communities. Freshwater Biology, 14, '257-
<br />280.
<br />Gregory S,V" Swanson F,J., McKee WA, & Cummins
<br />K.W, (1991) An ecosystem perspective ofriparian zones,
<br />BioScience, 41, 540-551.
<br />Gurtz M,E, (1994) Design of biological components of
<br />the National Water-Quality Assessment (NAWQA)
<br />Program, Biological Monitoring of Aquatic Systems (eds
<br />S, L. Loeb and A Spacie), pp, 323-354, Lewis Publishers,
<br />Boca Raton, FL,
<br />HiIIM,O, (1979) DECORANA - A FORTRAN Program for
<br />Detrended Correspondence Analysj~ and Reciprocal
<br />
|