. Bulletin. Science. DIAZINON IN THE CHOLLAS CREEK WATERSHED 35 Legend ...:er quality sample station .â ^ Sediment quality sample station Residential Commercial and Office ff$ Industrial Transportation Puolc F*o*t>es and Utilities Parks and Recreation Agncuiture Undeveloped Water I. bi>yr==a Fig. 1. Sampling sites on Chollas Creek, and associated land use of the Chollas Creek watershed. Note. *DPR(2), PRISM1, PRISM2, SD8(1) CC-N1, CC-N2, CC-S1, CC-S2 were sampling sites from Weston Solutions, Inc., 2006. inch in water year), storm event precipitation, intensity (the amount of precipi
. Bulletin. Science. DIAZINON IN THE CHOLLAS CREEK WATERSHED 35 Legend ...:er quality sample station .â ^ Sediment quality sample station Residential Commercial and Office ff$ Industrial Transportation Puolc F*o*t>es and Utilities Parks and Recreation Agncuiture Undeveloped Water I. bi>yr==a Fig. 1. Sampling sites on Chollas Creek, and associated land use of the Chollas Creek watershed. Note. *DPR(2), PRISM1, PRISM2, SD8(1) CC-N1, CC-N2, CC-S1, CC-S2 were sampling sites from Weston Solutions, Inc., 2006. inch in water year), storm event precipitation, intensity (the amount of precipitation in centimeters per hour during storm event), and annual cumulative precipitation. Annual cumulative precipitation was calculated based on a water year, from October to September of the following year. Flow measurements for Chollas Creek during this study were not available. A Mann-Whitney U test (Mann and Whitney 1947) was performed to compare diazinon levels before the pesticide's phase-out period (1998-2004) to levels after the phase-out was completed (2005), and a Kendall's test (Kendall 1955) was performed to determine if the declining trend in levels of diazinon from 1998 through 2005, has been significant. Quality Assurance (QA) and Quality Control (QC) Procedures Quality control samples consisted of field blanks, field duplicate samples, and lab duplicate samples. Precision for all samples were within the objective for diazinon of 25% which was previously established (San Diego Baykeeper 2005), except for a single sample (Site 4 on March 29, 2006) which showed precision of 26%. Overall precision was for all tests. Additionally, QA/QC procedures consisted of enrichment of natural Chollas Creek waters at each sampling site, with at least two different levels (100 ppt and 200 ppt or 500 ppt) of diazinon spiked into these samples, in order to determine the accuracy of the ELISA method. Accuracy of the ELISA test for diazinon-spiked samples for each rain event r
Size: 1880px × 1330px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionbiodiversity, booksubjectscience
