Macroinvertebrate assemblages on woody debris and their relations with environmental variables in the lower Sacramento and San Joaquin River drainages, California

Brown, L. R.; May, J. T.

Abstract:

Data from 25 sites were used to evaluate associations between macroinvertebrate assemblages on large woody debris (snags) and environmental variables in the lower San Joaquin and Sacramento River drainages in California as part of the U.S. Geological Survey‘s National Water Quality Assessment Program. Samples were collected from 1993 to 1995 in the San Joaquin River drainage and in 1996 and 1997 in the Sacramento River drainage. Macroinvertebrate taxa were aggregated to the family (or higher) level of taxonomic organization, resulting in 39 taxa for analyses. Only the 31 most common taxa were used for two-way indicator species analysis (TWINSPAN) and canonical correspondence analysis (CCA). TWINSPAN analysis defined four groups of snag samples on the basis of macroinvertebrate assemblages. Analysis of variance identified differences in environmental and biotic characteristics among the groups. These results combined with the results of CCA indicated that mean dominant substrate type, gradient, specific conductance, water temperature, percentage of the basin in agricultural land use, percentage of the basin in combined agricultural and urban land uses, and elevation were important factors in explaining assemblage structure. Macroinvertebrate assemblages on snags may be useful in family level bioassessments of environmental conditions in valley floor habitats.

Genre:

Article

ProdID:

70022589

Citation Author:

Brown, L. R.; May, J. T.

Citation Contributing Office:

Citation Datum:

Citation Day:

Citation Edition:

Citation Editor:

Citation End Page:

329

Citation Issue:

Citation Keywords:

Citation Language:

English

Citation Larger Work Title:

Environmental Monitoring and Assessment

Citation LatN:

Citation LatS:

Citation LonE:

Citation LonW:

Citation Month:

Citation No Pagination:

Citation Number Of Pages:

Citation Online Only Flag:

Citation Phsyical Description:

Citation Projection:

Citation Public Comments:

Citation Publisher:

Citation Series:

Citation Series Code:

Citation Series Number:

Citation Search Results Text:

Macroinvertebrate assemblages on woody debris and their relations with environmental variables in the lower Sacramento and San Joaquin River drainages, California; 2000; Article; Journal; Environmental Monitoring and Assessment; Brown, L. R.; May, J. T.