HR: 1330h
AN: NB33B-01    [Abstracts]
TI: Biological Assessment of Urban and Agricultural Streams in the California Central Valley (Fall 2002 Through Spring 2004)
AU: * Bacey, J
EM: nbacey@cdpr.ca.gov
AF: CA Department of Pesticide Regulation, 1001 I St., Sacramento, CA 95817 United States
AU: Moncada, A
EM: nbacey@cdpr.ca.gov
AF: CA Department of Pesticide Regulation, 1001 I St., Sacramento, CA 95817 United States
AB: California has over 200,000 miles of rivers and streams that are increasingly impacted from human activities. Various agencies in the state have begun to conduct bioassessment to evaluate these impacts. We conducted a pilot study to assess potential aquatic impacts of pesticides and other human activities in two urban creeks and two agricultural creeks in the fall and spring for two years (2002-04) using a modified U.S. EPA EMAP method. All creeks showed highly impacted conditions. Water quality measurements indicated below normal dissolved oxygen levels at 44% and 15% of the sites, and elevated temperatures at 70% and 73% of the urban and agricultural sites, respectively. Physical habitat scores indicated significant impacts. Diazinon and chlorpyrifos were detected at all sites (trace to 0.212 ppb). Pyrethroids were detected in water and sediment in urban sites only (trace to 27.5 ppt). High numbers of chironomidae and very low numbers of pollution intolerant species were detected in the benthic macroinvertebrate community. Urban creeks had a higher number of pollution tolerant species compared to agricultural creeks. All sites were ecologically impacted. Mulitvariate ANOVA of macroinvertebrate metrics revealed a significant difference between urban and agricultural sites (P= 0.002) and between fall and spring seasons (P=0.036).
UR: http://www.cdpr.ca.gov/docs/empm/pubs/ehapreps/Bioasse1.pdf
DE: 1803 Anthropogenic effects
DE: 1871 Surface water quality
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly