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Nitrapyrin, 6-CPA, and herbicide concentrations in agricultural soils, subsurface drains, and corresponding streams in the Midwestern US

June 28, 2018
Nitrapyrin is a nitrification inhibitor that is co-applied with N-fertilizer in agroecosystems. Over the course of one year (March 2016 to June 2017), 192 water samples from seven streams across Iowa and Illinois were analyzed for nitrapyrin, its degradate 6-chloropicolinic acid (6-CPA), and three widely used herbicides acetochlor, atrazine, and metolachlor. Additional environmental samples were collected and analyzed in spring 2017: 63 water samples from eight subsurface drains, and 33 soil samples from a field in Iowa that received direct application of nitrapyrin (only for nitrapyrin and herbicides). Nitrapyrin was detected in all seven streams (56% detection) with concentrations ranging from 4 to 1,200 ng/L; 6-CPA was detected in six of the seven streams (13% detection) with concentrations ranging from 2 to 13 ng/L. Nitrapyrin was detected in only two of the eight subsurface drains and in 10% of drain samples (10% detection), and with concentrations ranginged from 3 to 12 ng/L; 6-CPA was detected in six of the eight subsurface drains and in (33% of drain samples withdetection), and concentrations ranginged from 2 to 6 ng/L. Nitrapyrin was detected in 67% of the soil samples collected, and concentrations ranged from 0.9 to 42 ng/g. Generally, all three herbicides were detected more frequently and at higher concentrations than nitrapyrin in the streams, subsurface drains, and soils. There are 3 csv datasets related to this data release. Please find in each of the child items the data and metadata.
Publication Year 2018
Title Nitrapyrin, 6-CPA, and herbicide concentrations in agricultural soils, subsurface drains, and corresponding streams in the Midwestern US
DOI 10.5066/P91OESMG
Authors Emily E Woodward, Michelle L Hladik, Dana W Kolpin
Product Type Data Release
Record Source USGS Asset Identifier Service (AIS)
USGS Organization Sacramento Projects Office (USGS California Water Science Center)
Rights This work is marked with CC0 1.0 Universal
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