Environmental Monitoring and Assessment

, Volume 121, Issue 1, pp 245–262

Spatial Relationships Between Water Quality and Pesticide Application Rates in Agricultural Watersheds

  • John W. Hunt
  • Brian S. Anderson
  • Bryn M. Phillips
  • Ron S. Tjeerdema
  • Nancy Richard
  • Val Connor
  • Karen Worcester
  • Mark Angelo
  • Amanda Bern
  • Brian Fulfrost
  • Dustin Mulvaney
Article

DOI: 10.1007/s10661-005-9118-0

Cite this article as:
Hunt, J.W., Anderson, B.S., Phillips, B.M. et al. Environ Monit Assess (2006) 121: 245. doi:10.1007/s10661-005-9118-0

Abstract

Pesticide applications to agricultural lands in California, USA, are reported to a central data base, while data on water and sediment quality are collected by a number of monitoring programs. Data from both sources are geo-referenced, allowing spatial analysis of relationships between pesticide application rates and the chemical and biological condition of water bodies. This study collected data from 12 watersheds, selected to represent a range of pesticide usage. Water quality parameters were measured during six surveys of stream sites receiving runoff from the selected watershed areas. This study had three objectives: to evaluate the usefulness of pesticide application data in selecting regional monitoring sites, to provide information for generating and testing hypotheses about pesticide fate and effects, and to determine whether in-stream nitrate concentration was a useful surrogate indicator for regional monitoring of toxic substances. Significant correlations were observed between pesticide application rates and in-stream pesticide concentrations (p < 0.05) and toxicity (p < 0.10). In-stream nitrate concentrations were not significantly correlated with either the amount of pesticides applied, in-stream pesticide concentrations, or in-stream toxicity (all p > 0.30). Neither total watershed area nor the area in which pesticide usage was reported correlated significantly with the amount of pesticides applied, in-stream pesticide concentrations, or in-stream toxicity (all p > 0.14). In-stream pesticide concentrations and effects were more closely related to the intensity of pesticide use than to the area under cultivation.

Keywords

land usepesticide use reportsdiazinonchlorpyrifospyrethroidtoxicityCeriodaphnia dubiaHyalella aztecaGISwatershed

Copyright information

© Springer Science+Business Media, Inc. 2005

Authors and Affiliations

  • John W. Hunt
    • 1
  • Brian S. Anderson
    • 1
  • Bryn M. Phillips
    • 1
  • Ron S. Tjeerdema
    • 1
  • Nancy Richard
    • 2
  • Val Connor
    • 2
  • Karen Worcester
    • 3
  • Mark Angelo
    • 3
  • Amanda Bern
    • 3
  • Brian Fulfrost
    • 4
  • Dustin Mulvaney
    • 4
  1. 1.Department of Environmental Toxicology, Marine Pollution Studies Laboratory at Granite CanyonUniversity of California, DavisMontereyUSA
  2. 2.California State Water Resources Control BoardSacramentoUSA
  3. 3.California Regional Water Quality Control BoardSan Luis ObispoUSA
  4. 4.Department of Environmental StudiesUniversity of California, Santa Cruz, GIS Technology LaboratorySanta CruzUSA