HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (6) Citing Articles via Google Scholar Google Scholar Articles by Tate, K. W. Articles by Nader, G. Search for Related Content PubMed PubMed Citation Articles by Tate, K. W. Articles by Nader, G. Agricola Articles by Tate, K. W. Articles by Nader, G. Related Collections Surface Water Quality Best Management Practices Microorganisms Water Pollution Animal Waste

Significant Escherichia coli Attenuation by Vegetative Buffers on Annual Grasslands

^a Department of Plant Sciences, Mail Stop 1, One Shields Avenue, University of California, Davis, CA 95616-8515
^b Veterinary Medicine Teaching and Research Center, School of Veterinary Medicine, University of California, 18830 Road 112, Tulare, CA 93274
^c Department of Environmental Science Policy and Management, 151 Hilgard Hall #3110, University of California, Berkeley, CA 94720-3114
^d University of California Cooperative Extension, 142A Garden Highway, Yuba City, CA 95991-5593

View larger version (31K): [in a new window]   Fig. 1. Runoff plot design and layout of buffer and residual dry matter (RDM) treatments for 5, 20, and 35% land slope treatment blocks.

View larger version (12K): [in a new window]   Fig. 2. Cumulative rainfall (cm), storm runoff collection timing, and fecal material application dates during the portions of the 2002 rainfall season (12 Mar. 2003 to 4 May 2003) and 2003 rainfall season (14 Dec. 2003 to 2 Mar. 2004) included in the study period.

View larger version (17K): [in a new window]   Fig. 3. Change in mean concentration of E. coli (cfu/100 mL) in surface water runoff samples held for 6, 24, 48, and 72 h from collection (time = 0 h) before processing. Data points represent the mean concentration of five replicates with an initial concentration of 103, 104, 106, and 107 cfu/100 mL, respectively. Error bars report one standard error of the mean.

View larger version (17K): [in a new window]   Fig. 4. Total rainfall (mm) and mean maximum daily temperature (°C) observed for each month of the 2002–2003 rainfall season, the 2003 dry season, and the 2003–2004 rainfall season with long term monthly means for the period of record (1989 through 2004) at the U.C. Sierra Foothill Research and Extension Center official weather station (California Irrigation Management Information System, Station #84).

View larger version (14K): [in a new window]   Fig. 5. Mean total E. coli (cfu) discharged from 48, 2.0-m-wide by 3.0-m-long annual grassland runoff plots across the 2002–2003 and 2003–2004 rainfall seasons following application of a total of 41.5 x 109 E. coli (cfu) in cattle fecal material. (a) Mean discharge for buffer treatments of 0.1-m buffer, 1.1-m buffer, 2.1-m buffer, and a no fecal application negative control; calculated by combining rainfall season, land slope, and residual dry matter treatments. (b) Mean discharge for residual dry vegetation matter in October treatments of 225, 560, 900, and 4500 kg/ha; calculated by combining rainfall season, land slope, and buffer treatments. (c) Mean discharge for land slope treatments of 5, 20, and 35%; calculated by combining rainfall season, buffer, and residual dry matter treatments. Error bars report one standard error of the mean.

View larger version (17K): [in a new window]   Fig. 6. Observed total E. coli [log10(cfu + 1)] discharged from annual grassland runoff plots versus values predicted by linear mixed effects model which contained year, buffer width, residual dry vegetative matter, land slope, and runoff as independent factors.

View larger version (21K): [in a new window]   Fig. 7. Relationship of total E. coli discharge (cfu) and log10 reduction in discharge due to buffer width and total runoff for storm series observed during portions of the 2002–2003 and 2003–2004 rainfall seasons contained in the study period. Slope and residual dry matter level set to 20% and 900 kg/ha, respectively.

View larger version (19K): [in a new window]   Fig. 8. Relationship of total E. coli discharge (cfu) and log10 reduction in discharge due to residual dry vegetation matter and land slope for storm series observed during portions of the 2002–2003 and 2003–2004 rainfall season contained in the study period.