| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
a U.S. Geological Survey, 6000 J St., Sacramento, CA 95819
b U.S. Geological Survey, 8987 Yellow Brick Rd., Baltimore, MD 21237
c U.S. Geological Survey, 308 South Airport Rd., Jackson, MS 39208
d U.S. Geological Survey, 10615 S.E. Cherry Blossom Dr., Portland, OR 97216
e U.S. Geological Survey, 5957 Lakeside Blvd., Indianapolis, IN 46278
f U.S. Geological Survey, National Water Quality Lab., Denver Federal Center, Building 95, Lakewood, CO 80225
* Corresponding author (joed{at}usgs.gov).
Received for publication August 2, 2007. Agricultural chemical transport to surface water and the linkage to other hydrological compartments, principally ground water, was investigated at five watersheds in semiarid to humid climatic settings. Chemical transport was affected by storm water runoff, soil drainage, irrigation, and how streams were linked to shallow ground water systems. Irrigation practices and timing of chemical use greatly affected nutrient and pesticide transport in the semiarid basins. Irrigation with imported water tended to increase ground water and chemical transport, whereas the use of locally pumped irrigation water may eliminate connections between streams and ground water, resulting in lower annual loads. Drainage pathways in humid environments are important because the loads may be transported in tile drains, or through varying combinations of ground water discharge, and overland flow. In most cases, overland flow contributed the greatest loads, but a significant portion of the annual load of nitrate and some pesticide degradates can be transported under base-flow conditions. The highest basin yields for nitrate were measured in a semiarid irrigated system that used imported water and in a stream dominated by tile drainage in a humid environment. Pesticide loads, as a percent of actual use (LAPU), showed the effects of climate and geohydrologic conditions. The LAPU values in the semiarid study basin in Washington were generally low because most of the load was transported in ground water discharge to the stream. When herbicides are applied during the rainy season in a semiarid setting, such as simazine in the California basin, LAPU values are similar to those in the Midwest basins.
Abbreviations: DEA, deethylatrazine • ESA, ethane-sulfonic acid • LAPU, load as a percent of use • OXA, oxanilic acid
This article has been cited by other articles:
|
|
 |
|
  P. D. Capel, K. A. McCarthy, and J. E. Barbash National, Holistic, Watershed-Scale Approach to Understand the Sources, Transport, and Fate of Agricultural Chemicals J. Environ. Qual., May 1, 2008; 37(3): 983 - 993. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. J. Puckett, C. Zamora, H. Essaid, J. T. Wilson, H. M. Johnson, M. J. Brayton, and J. R. Vogel Transport and Fate of Nitrate at the Ground-Water/Surface-Water Interface J. Environ. Qual., May 1, 2008; 37(3): 1034 - 1050. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. C. Hancock, M. W. Sandstrom, J. R. Vogel, R. M.T. Webb, E. R. Bayless, and J. E. Barbash Pesticide Fate and Transport throughout Unsaturated Zones in Five Agricultural Settings, USA J. Environ. Qual., May 1, 2008; 37(3): 1086 - 1100. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. R. Vogel, M. S. Majewski, and P. D. Capel Pesticides in Rain in Four Agricultural Watersheds in the United States J. Environ. Qual., May 1, 2008; 37(3): 1101 - 1115. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Crop Science | |||
| Journal of Natural Resources and Life Sciences Education |
Vadose Zone Journal | ||||
| Soil Science Society of America Journal | Journal of Plant Registrations | The Plant Genome | |||
