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Universi^ Micionlms International 300 N INFORMATION TO USERS This reproduction was made from a copy of a document sent to us for microfilming. While the most advanced technology has been used to photograph and reproduce this document, the quality of the reproduction is heavily dependent upon the quality of the material submitted. The following explanation of techniques is provided to help clarify markings or notations which may appear on this reproduction. 1. The sign or "target" for pages apparently lacking from the document photographed is "Missing Page(s)". If it was possible to obtain the missing page(s) or section, they are spliced into the film along with adjacent pages. This may have necessitated cutting through an image and duplicating adjacent pages to assure complete continuity. 2. When an image on the film is obliterated with a round black mark, it is an indication of either blurred copy because of movement during exposure, duplicate copy, or copyrighted materials that should not have been filmed. For blurred pages, a good image of the page can be found in the adjacent frame. If copyrighted materials were deleted, a target note will appear listing the pages in the adjacent frame. 3. When a map, drawing or chart, etc., is part of the material being photographed, a definite method of "sectioning" the material has been followed. It is customary to begin filming at the upper left hand comer of a large sheet and to continue from left to right in equal sections with small overlaps. If necessary, sectioning is continued again—beginning below the first row and continuing on until complete. 4. For. illustrations that cannot be satisfactorily reproduced by xerographic means, photographic prints can be purchased at additional cost and inserted into your xerographic copy. These prints are available upon request from the Dissertations Customer Services Department. 5. Some pages in any document may have indistinct print. In all cases the best available copy has been filmed. Universi^ Micionlms International 300 N. Zeeb Road Ann Arbor, Ml 48106 8316338 Wysocki, Donald John CHARACTERIZATION OF THE LOAMY SURFICIAL SEDIMENTS IN A TYPE AREA OF THE lOWAN EROSION SURFACE Iowa State University PH.D. 1983 University Microfilms InternatiOnEll 300 N. Zeeb RW. Ann Arbor, MI 48106 Characterization of the loamy surficial sediments in a type area of the lowan Erosion Surface by Donald John Wysocki A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY Department: Agronomy Major: Soil Morphology and Genesis Approved: Signature was redacted for privacy. In Charge of Major Work Signature was redacted for privacy. Fqj/Ote Major Department Signature was redacted for privacy. For the Graduate College Iowa State University Ames, Iowa 1983 ii TABLE OF CONTENTS Page INTRODUCTION 1 History of the lowan Area 1 Models of Landscape Evolution 10 Study of Hi 11siopes and Their Sediments 19 Studies of hillslope position 21 Hi 11si ope Studies on the lowan Surface and Adjacent Areas 26 Summary of the Introduction 27 DESCRIPTION OF THE STUDY 29 Description of the Study Area 29 METHODS AND PROCEDURES 42 Field Methods 42 Selection of transects 42 Collection of cores 42 Shallow cores 42 Deep cores 42 Bulk density 43 Laboratory Procedures 43 Description and sampling of the soil profiles 43 Particle size analysis 43 Pipette 43 Sedigraph 43 Sand fractionation 47 Organic carbon 47 Available phosphorus 47 Clay mineralogy 47 iii Page RESULTS AND DISCUSSION 49 Soil Color Product 50 Thickness of the Loamy Surficial Sediments 61 Particle Size Characteristics 71 Clay content 72 Geometric mean 85 Fine/coarse particle ratio 101 Sand content 111 Bulk Density and Organic Carbon Content 127a Available Phosphorus 131 Clay Mineralogy 137 SUMMARY AND CONCLUSIONS 145 Characterization of the Loamy Surficial Sediments within the Study Area 146 Origin of the sediments 148 Geomorphic and time setting 148 Loamy Sediments on the lowan Erosion Surface 150 Ruhe's Model of Landscape Evolution 152 Suggestions for Further Study of the Surficial Loamy Sediments 152 LITERATURE CITED 155 ACKNOWLEDGMENTS 163 APPENDIX A. SOIL PROFILE DESCRIPTIONS 165 List of Abbreviations 165 Texture 165 Mottles 165 Structure 165 Consistence 165 Clay films 166 iv Page Effervescence 166 Boundary 166 Transect 1 167 Transect 2 169 Transect 3 172 Transect 4 174 Transect 5 178 Transect 6 182 Deep Cores 185 APPENDIX B. SOIL PROFILE DATA 188 V LIST OF TABLES Page Table 1. A comparison of the particle size data from 20 samples of a Fayette C horizon analyzed by the sedigraph and pi pette methods 44 Table 2. A comparison of particle size data for a Floyd clay loam obtained by the sedigraph and pipette methods 46 Table 3. Numerical values given to color hue and contrast of mottling to determine the color product 50 Table 4. Color characteristics of the basal horizon of the loany surficial sediments along transects 1, 2, and 3 51 Table 5. Color characteristics of the basal horizon of the loatny surficial sediments along transects 4, 5, and 6 52 Table 6. Thicknesses of the loamy surficial sediments along the six hi 11si ope transects 62 Table 7a. Average clay content of the loamy surficial sedi­ ments along the six hi 11 slope transects 73 Table 7b. Linear regression equations and correlation coeffi­ cients which related the particle size characteristics of the loamy sediments to the materials underlying the stone line 84h Table 8. Weighted average geometric means of the loamy surficial sediments along the six hillslope transects 86 Table 9. Weighted average ratio of the fine (16-250 ym) to coarse (.250-2.0 mm) particle fractions of the loamy surficial sediments along the six hillslope transects 102 Table 10. Average sand content of the surficial loamy sediments along the six hillslope transects 112 Table 11. Weighted average bulk densities and organic carbon content of the loany surficial sediments along transect 5 127b Table 12. Weighted average available phosphorus content of the loamy surficial sediments along transects 1,3, and 5 131 vi LIST OF FIGURES Page Figure 1. Location of the lowan Erosion Surface (from Ruhe, 1969) 2 Figure 2. Present stratigraphie nomenclature for east-central and northeast Iowa (after Hall berg, 1980) 9 Figure 3. Theories of slope evolution (after Davis, 1899; Penck, 1924; and King, 1953) 11 Figure 4. Slope components of fully developed slopes (from Wood, 1942; King, 1957; and Ruhe, 1960) 13 Figure 5. Slope modification by parallel retreat 16 Figure 6. Three dimensional attack on an interfluve by the processes of pedimentation (after Ruhe et al., 1967) 18 Figure 7. A stepped erosion surface and its temporal characteristics 20 Figure 8. The influence of slope upon soil thickness and depth to the water table 23 Figure 9. Location of Butler County, Iowa 30 Figure 10. Location of the study in Butler County, Iowa 31 Figure 11. Soil map of the study area 33 Figure 12. Topographic map of the study area showing the loca­ tions of the hillslope transects and deep soil cores 34 Figure 13. Cross sectional diagram of transect 1 showing the slope profile, elevations, and thickness of loamy surficial sediments 35 Figure 14. Cross sectional diagram of transect 2 showing the slope profile, elevations, and thickness of loamy surficial sediments 36 Figure 15. Cross sectional diagram of transect 3 showing the slope profile, elevations, and thickness of loamy surficial sediments 37 vii Page Figure 16. Cross sectional diagram of transect 4 showing the slope profile, elevations, and thickness of loamy surficial sediments 38 Figure 17. Cross sectional diagram of transect 5 showing the slope profile, elevations, and thickness of loamy surficial sediments 39 Figure 18. Cross sectional diagram of transect 6 showing the slope profile, elevations, and thickness of loainy surficial sediments 40 Figure 19. A schematic example of the printout of the Sedi graph 50000 45 Figure 20. Mathematical description of the color product along hillslope transect 1 54 Figure 21. Mathematical description of the color product along hillslope transect 2 55 Figure 22. Mathematical description of the color product along hillslope transect 3 56 Figure 23. Mathematical description of the color product along hillslope transect 4 57 Figure 24. Mathematical description of the color product along hillslope transect 5 58 Figure 25. Mathematical description of the color product along hillslope transect 6 59 Figure 26. Mathematical description of the color product for all transects combined 60 Figure 27. Mathematical description of the thickness of the loamy surficial sediments along transect 1 63 Figure 28. Mathematical description of the thickness of the loamy surficial sediments along transect 2 64 Figure 29. Mathematical description of the thickness of the loamy surficial sediments along transect 3 65 Figure 30. Mathematical description of the thickness of the loamy surficial sediments along transect 4 66 vm Page Figure 31. Mathematical description of the thickness of the loamy surficial sediments along transect 5 67 Figure 32. Mathematical description of the thickness of the loamy surficial sediments along transect 6 68 Figure 33. Mathematical description of the thickness of the loany surficial sediments from all transects combined 69 Figure 34. Mathematical description of the clay content of the loamy surficial sediments along hi 11siope transect 1 74 Figure 35. Clay content of the loamy surficial sediments along hi11 siope transect 2 75 Figure 36. Mathematical description of the clay content of the loamy surficial sediments along hi 11 si ope transect 2 fitted by regression analysis 76 Figure 37. Mathematical description of the clay content of the loainy surficial sediments along hi 11 slope transect 3 77 Figure 38. Clay content of the loamy surficial sediments along hi 11si ope transect 4 78 Figure 39. Mathematical description of the clay content of the loamy surficial sediments along hillslope transect 4, fitted by regression analysis 79 Figure 40.
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