Fig. 6. Frequencies of herbicide detection in ground water for the NAWQA study in relation to agricultural use (Gianessi and Anderson, 1996); (a) atrazine, (b) metolachlor. LUSs, land-use studies; SUSs, subunit surveys.
Fig. 6. Frequencies of herbicide detection in ground water for the NAWQA study in relation to agricultural use (Gianessi and Anderson, 1996); (a) atrazine, (b) metolachlor. LUSs, land-use studies; SUSs, subunit surveys.