Herbicides in Metro Atlanta Streams and Rivers Data Analysis Cristal Moon
Herbicides in Metro Atlanta Streams and Rivers
Data Analysis
Cristal Moon
Rivers
Suwanee Creek
Nickajack Creek
Chattahoochee River
Questions• Do herbicide levels have yearly trends?• Are they related to other factors in surface
water?
Variability of two Pesticides in Chattahoochee
Levels for Nickajack Creek
Levels for Suwanee Creek
Least Squares Regression
+ is levels, green line is regression, red bars are 95% confidence levels
Error variance=0.3095Correlation Coefficient= 0.1375P-value=0.1814
Error variance=0.0089Correlation Coefficient= 0.1681P-value=0.1016
Normal?
Chi2=4,337,300Chi2inv=118.7516Chi2>Chi2inv, therefore distribution is not normal
Chi2= 527.3569, Chi2inv=118.7516Chi2>Chi2inv, therefore distribution is not normal
Discharge vs. Herbicides
Correlation Coefficient: 0.0374P-value=0.7174
Correlation Coefficient: -0.0133P-value= 0.8974
Specific Conductance vs. Herbicides
Correlation Coefficient= -0.1757P-value= 0.0868
Correlation Coefficient= -0.2161P-value= 0.0344
pH
Correlation Coefficient= 0.0063P-value= 0.9515
Correlation Coefficient=-0.0919P-value= 0.3732
Principle Component Regression
Green is Least-Squares, Blue is Reduced Major Axis, Black is PCR
LSSA
Significant frequencies (in Hz) at 0.97765Corresponding powers: 16.0276
Significant frequencies (in Hz) at 0.97765Corresponding powers: 8.7976
Conclusions
• Annual increase in herbicides early in year• Linear increase over time• Levels not related to pH or discharge• Specific Conductance somewhat correlated