Fig 1.
Simulated EIQ values for low, medium, and high risk categories for each risk factor used in the herbicide EIQ calculation (Eq 1).
Dark bars represent median EIQ value, boxes enclose the first and third quartiles, and whiskers extend to minimum and maximum observed EIQ values.
Fig 2.
Histogram of Monte Carlo simulation of 100,000 EIQ values calculated by random draws of values for risk factors included in the EIQ formula (Eq 1).
For box-plots, dark bars represent median EIQ value, boxes enclose the first and third quartiles, and whiskers extend to minimum and maximum observed EIQ values.
Table 1.
The influence of risk factors on the calculated environmental impact quotient (EIQ) as determined by simulation analysis (N = 100,000).
Table 2.
The influence of risk factors on the calculated environmental impact quotient (EIQ) as determined by simulation analysis (N = 100,000) for herbicides applied before crop emergence (PRE) and herbicides applied after crop emergence (POST).
Fig 3.
Relationship between Field EIQ and herbicide use rate (A,B) and the EIQ (C,D) for two herbicide data sets.
(A) Relationship between maximum herbicide use rate and Field EIQ for Senseman data set; (B) relationship between herbicide field use rate and Field EIQ for Beckie data set; (C) relationship between herbicide EIQ and Field EIQ for the Senseman data set; (D) relationship between herbicide EIQ and Field EIQ for the Beckie data set. Spearman’s rank correlation rho and P-value are provided in each panel.
Fig 4.
The relationship between plant surface half-life risk factor (P) and EIQ value for 116 herbicides (Senseman data set).
Filled circles with error bars represent means and standard errors, grey open circles represent individual herbicides (N = 116). For box-plots, dark bars represent median EIQ value, boxes enclose the first and third quartiles; preemergence (PRE) and postemergence (POST) boxplots represent the data for P = 1 and P = 3, respectively.