The Impact of Soil Characteristics and Land Use on Atrazine Sorption: A Meta-Analysis Approach.

Atrazine is one of the most widely used herbicides worldwide, but atrazine contamination of groundwater is of great concern, especially in certain soil and environmental conditions. Sorption plays an essential role in atrazine environmental fate and behavior. This research aims to determine how soil characteristics and land use impact atrazine sorption by using a statistical meta-analysis approach. We collected hundreds of observations of soil characteristics, land use, and atrazine sorption data from the past 30 years of literature to determine the key factors influencing atrazine sorption. PROC MIXED MODEL was used in the statistical analysis with 1) soil characteristics and land use as fixed explanatory variables, 2) author information as random variables, 3) replicates of experiment as weights, and 4) sorption parameters as response variables. The analysis shows that among soil organic carbon (SOC), pH, silt, clay, and, CEC, SOC and pH are the most important parameters to predict sorption of atrazine. There is a general trend of increasing Freundlich adsorption coefficient (K_f) to an increasing SOC content. However, no clear linear pattern was observed. We propose a succinct linear relationship between K_f and SOC may be region or laboratory specific, which is justified by our laboratory sorption isotherm experiments on soils collected in North Carolina.