Relating Atrazine Degradation Rate in Soil to Environmental Conditions: Implications for Global Fate Modeling

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• 作者：Kathrin Fenner ; Valentin A. Lanz ; Martin Scheringer ; Mark E. Borsuk
• 刊名：Environmental Science & Technology
• 出版年：2007
• 出版时间：April 15, 2007
• 年：2007
• 卷：41
• 期：8
• 页码：2840 - 2846
• 全文大小：145K
• 年卷期：v.41,no.8(April 15, 2007)
• ISSN：1520-5851

文摘

With the ready availability of georeferenced environmentaldata, regional and global chemical fate models havebecome increasingly spatially explicit. However, thedescription of how chemical fate properties such asdegradation rate constants and partition coefficients dependon environmental conditions has not kept up with thesedevelopments. Consequently, model results are often subjectto large uncertainty stemming from inherent variability inthese properties. Here, we present an extensive meta-analysisof soil degradation of one exemplary compound, theherbicide atrazine. In the first part of the paper, we presentthe results of an in-depth statistical analysis of thedependence of atrazine degradation rate constants onvarious environmental factors. In the second part, the resultingestimation equation for atrazine degradation rate constantsis implemented in CliMoChem, a model for the predictionof global chemical fate, which we supplemented with spatialinformation on various soil descriptors, such as temperature,sand and clay content, organic carbon content, andpH. Estimates of polar accumulation, an important indicatorof global chemical fate, were then compared betweenthis model setup and estimates obtained when the degradationrate constant is represented by a single value or asbeing dependent on temperature only. Results for thethree rate estimation methods demonstrate that a spatiallyexplicit description of the soil degradation processresults in 4-fold higher estimates of polar accumulation,while reducing uncertainty in the prediction of this endpointby more than 40%.