Herbicide and nitrate distribution in central Iowa rainfall

被引:38
作者
Hatfield, JL [1 ]
Wesley, CK [1 ]
Prueger, JH [1 ]
Pfeiffer, RL [1 ]
机构
[1] PRINCETON UNIV,PRINCETON,NJ 08544
关键词
D O I
10.2134/jeq1996.00472425002500020008x
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
Herbicides are detected in rainfall; however, these are a small fraction of the total applied. This study was designed to evaluate monthly and annual variation in atrazine (6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine) alachlor (2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide metolachlor (2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide), and NO3-N concentrations in rainfall over Walnut Creek watershed south of Ames, IA. The study began in 1991 and continued through 1994. Within the watershed, two wet/dry precipitation samplers were positioned 4 km apart. Detections varied during the year with >90% of the herbicide detections occurring in April through early July. Concentrations varied among events from nondetectable amounts to concentrations of 154 mu g L(-1), which occurred when atrazlne was applied during an extremely humid day immediately followed by rainfall of <10 mm that washed spray drift from the atmosphere. This was a local scale phenomenon, because the other collector had a more typical concentration of 1.7 mu g L(-1) with an 8-mm rainfall. Variation between the two collectors suggests that local scale meteorological processes affect herbicide movement. Yearly atrazine deposition totals were >100 mu g m(-2) representing <0.1% of the amount applied. Nitrate-N concentrations in precipitation were uniformly distributed throughout the year and without annual variation in the concentrations. Deposition rates of NO3-N were about 1.2 g m(-2). Annual loading onto the watershed was about 25% of the amount applied from all forms of N fertilizers. Movement and rates of deposition provide an understanding of the processes and magnitude of the impact of agriculture on the environment.
引用
收藏
页码:259 / 264
页数:6
相关论文
共 7 条
[1]   ATRAZINE AND OTHER S-TRIAZINE HERBICIDES IN LAKES AND IN RAIN IN SWITZERLAND [J].
BUSER, HR .
ENVIRONMENTAL SCIENCE & TECHNOLOGY, 1990, 24 (07) :1049-1058
[2]  
GOOLSBY DA, 1990, NEW DIRECTIONS PESTI, P697
[3]   PESTICIDES IN IOWA PRECIPITATION [J].
NATIONS, BK ;
HALLBERG, GR .
JOURNAL OF ENVIRONMENTAL QUALITY, 1992, 21 (03) :486-492
[4]  
PFEIFFER RL, 1992, QUALITY ASSURANCE QU
[5]   PESTICIDES IN RAINWATER IN THE NORTHEASTERN UNITED-STATES [J].
RICHARDS, RP ;
KRAMER, JW ;
BAKER, DB ;
KRIEGER, KA .
NATURE, 1987, 327 (6118) :129-131
[6]  
SAUER PJ, 1994, NATIONAL SOIL TILTH, V941