Pesticide volatilization from soil and plant surfaces [Elektronische Ressource] : measurements at different scales versus model predictions / vorgelegt von André Wolters

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Informations

• Publié par: rheinisch-westfalischen_technischen_hochschule_-rwth-_aachen
• Publié le: 01 janvier 2003
• Nombre de lectures: 39
• Poids de l'ouvrage: 1 Mo

Extrait

Pesticide Volatilization from Soil and Plant Surfaces:
Measurements at Different Scales
versus Model Predictions



Von der Fakultät für Mathematik, Informatik und Naturwissenschaften der
Rheinisch-Westfälischen Technischen Hochschule Aachen zur Erlangung
des akademischen Grades eines Doktors der Naturwissenschaften
genehmigte Dissertation



vorgelegt von

Dipl.-Chem.
André Wolters
aus Schwalmtal (Nordrhein-Westfalen)





Berichter: Univ.-Prof. Dr. rer. nat. Andreas Schäffer
Univ.-Prof. Dr. agr. Harry Vereecken

Tag der mündlichen Prüfung: 25. Juni 2003



Diese Dissertation ist auf den Internetseiten der Hochschulbibliothek online verfügbar.
TABLE OF CONTENTS I

1 INTRODUCTION...................................................................................................1

1.1 Pesticides in the Atmosphere........................................................................... 2
1.1.1 Sources: Application and Post-application Processes ......................................... 2
1.1.2 Distribution: Transport Processes....................................................................... 3
1.1.3 Removal: Deposition and Photochemical Reactions........................................... 3
1.2 Key Process: Volatilization.............................................................................4
1.2.1 Overview: Experimental Determination............................................................. 5
1.2.2 Registration: German and European Guidelines ................................................. 7
1.3 Aims and Scope.............................................................................................10
2 THEORETICAL CONSIDERATIONS AND MODEL APPROACHES ........... 11

2.1 Pesticide Volatilization from Bare Soil...........................................................11
2.1.1 Factors Governing Volatilization from Soil...................................................... 12
2.1.2 Model Approaches: Volatilization from Soil.................................................... 14
2.1.2.1 Empirical Approaches: Volatilization from Soil ........................................... 15
2.1.2.1.1 Estimation Method: Smit et al. (1997).................................................. 15
2.1.2.1.2 Estimation Method: Woodrow & Seiber (1997).................................... 15
2.1.2.2 Screening Approach: Behavior Assessment Model ...................................... 16
2.1.2.3 Sophisticated Approaches: Improvement of PEC Models............................. 17
2.1.2.3.1 PEARL: Description of Volatilization from Soil................................... 18
2.1.2.3.2 PELMO: Description of Volatilization from Soil.................................. 19
2.2 Pesticide Volatilization from Plant Surfaces...................................................20
2.2.1 Factors Governing Volatilization from Plants .................................................. 21
2.2.2 Model Approaches: Volatilization from Plants................................................. 22
2.2.2.1 Empirical Approach: SMIT et al. (1998)...................................................... 22
2.2.2.2 Model Approach on the Basis of a Boundary-layer Concept......................... 23
3 EXPERIMENTAL METHODS AND INSTRUMENTATION ........................... 27

3.1 Volatilization Measurements at Different Scales ............................................27
3.1.1 Laboratory Studies: Photovolatility Chamber................................................... 27
3.1.1.1 Main Features of the Photovolatility Chamber ............................................. 28
3.1.1.2 Characterization of the Aerodynamic Conditions and Water Content ........... 30
3.1.1.3 Air sampling: Adsorption Capacity of the PUF plugs ................................... 30
3.1.1.4 Performance of Studies on Volatilization: Application Process .................... 31
3.1.1.5 Performance of Studies on Volatilization: Analysis...................................... 31
3.1.1.6 Process Studies on the Influence of Soil Moisture and Temperature............. 32
3.1.2 Semi-field Scale: Wind Tunnel ........................................................................ 33
3.1.2.1 Characteristics of the Wind Tunnel and Measuring Technique ..................... 33
3.1.2.2 Application Device: Semi-automatic Sprayer............................................... 34
3.1.2.3 Air Sampling Unit: High-volume Sampler and Medium-volume Sampler .... 34
3.1.2.4 Study on Volatilization from Soil Surfaces................................................... 36
3.1.2.5 Study on Volatilization from Plant Surfaces................................................. 37
3.1.3 Field Study: Micrometeorological Methods ..................................................... 38
II TABLE OF CONTENTS

3.1.3.1 Field Site and Application ............................................................................38
3.1.3.2 Meteorological Measurements......................................................................39
3.1.3.3 Plant and Soil Sampling...............................................................................40
3.1.3.4 Pesticide Concentrations in Air.....................................................................40
3.1.3.5 Micrometeorological Methods for Determining Volatilization Fluxes...........41
3.2 Phase Partitioning Studies.............................................................................42
3.2.1 Measurement of Soil-Air Partitioning Coefficients ...........................................42
3.2.1.1 A Novel Chamber for Partitioning Studies: Main Features............................42
3.2.1.2 Air Supply and Air Sampling Unit................................................................43
3.2.1.3 Studies on Soil-Air Partitioning....................................................................44
3.2.2 Measurement of Soil-Water Partitioning Coefficients.......................................44
3.2.2.1 Studies on Soil-Water Partitioning: Experimental Set-up..............................44
3.2.2.2 Calculation of Sorption Coefficients for Pesticides .......................................45
3.3 Analytics.......................................................................................................45
3.3.1 Sample Preparation..........................................................................................45
3.3.2 Radioactivity Measurements.............................................................................47
3.3.3 Quantification of Pesticides and Metabolites ....................................................47
3.3.3.1 Thin-layer Chromatography (TLC)...............................................................47
3.3.3.2 Gas Chromatography / Mass Selective Detector (GC-MSD) .........................48
3.3.3.3 High Pressure Liquid Chromatography (HPLC) ...........................................49
3.3.3.4 Thermodesorption System (TDS) .................................................................49
3.4 Test Compounds............................................................................................50
3.4.1 Parathion-methyl..............................................................................................51
3.4.2 Fenpropimorph.................................................................................................51
3.4.3 Terbuthylazine.................................................................................................51
3.4.4 Chlorpyrifos.....................................................................................................52
3.4.5 Quinoxyfen......................................................................................................52
3.5 Experimental Soil..........................................................................................52
3.5.1 Gleyic Cambisol...............................................................................................52
3.5.2 Orthic Luvisol..................................................................................................53
4 RESULTS AND DISCUSSION .............................................................................54

4.1 Volatilization from Bare Soil.........................................................................54
4.1.1 Laboratory Studies on Volatilization of Parathion-methyl ................................54
4.1.1.1 Measurements of Air Velocity and Pressure Differential ..............................54
4.1.1.2 Validation of the Total-volume Sampler (TVS) ............................................55
4.1.1.3 Water Content in the Soil Container .............................................................56
4.1.1.4 Validation of Uniform Spray Distribution Pattern.........................................57
4.1.1.5 Influence of Soil Moisture on Cumulative Volatilization and Kinetics ..........58
4.1.1.5.1 Radioactivity and Mass Balance ...........................................................58
4.1.1.5.2 Metabolization and Mineralization........................................................59
4.1.1.5.3 Cumulative Volatilization and Kinetics.................................................