Pressurized Hot Water: an Alternative Method of Nutrient Extraction and Subsequent Analysis for Use in Small-Scale Agriculture

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Pressurized Hot Water: an Alternative Method of Nutrient Extraction and Subsequent Analysis for Use in Small-Scale Agriculture Brigham Young University BYU ScholarsArchive Theses and Dissertations 2004-07-13 Pressurized Hot Water: An Alternative Method of Nutrient Extraction and Subsequent Analysis for Use in Small-Scale Agriculture Kristy Susanne Crane Brigham Young University - Provo Follow this and additional works at: https://scholarsarchive.byu.edu/etd Part of the Animal Sciences Commons BYU ScholarsArchive Citation Crane, Kristy Susanne, "Pressurized Hot Water: An Alternative Method of Nutrient Extraction and Subsequent Analysis for Use in Small-Scale Agriculture" (2004). Theses and Dissertations. 541. https://scholarsarchive.byu.edu/etd/541 This Thesis is brought to you for free and open access by BYU ScholarsArchive. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. PRESSURIZED HOT WATER: AN ALTERNATIVE METHOD OF NUTRIENT EXTRACTION AND SUBSEQUENT ANALYSIS FOR USE IN SMALL-SCALE AGRICULTURE by Kristy S. Crane A thesis submitted to the faculty of Brigham Young University in partial fulfillment of the requirements for the degree of Master of Science Department of Plant and Animal Sciences Brigham Young University August 2004 BRIGHAM YOUNG UNIVERSITY GRADUATE COMMITTEE APPROVAL of a thesis submitted by Kristy S. Crane This thesis has been read by each member of the following graduate committee and by majority vote has been found satisfactory. _________________________ ____________________________________ Date Phil S. Allen, Chair _________________________ ____________________________________ Date Bruce L. Webb _________________________ ____________________________________ Date Von D. Jolley _________________________ ____________________________________ Date Sheldon D. Nelson BRIGHAM YOUNG UNIVERSITY As chair of the candidate’s graduate committee, I have read the thesis of Kristy S. Crane in its final form and have found that (1) its format, citations, and bibliographical style are consistent and acceptable and fulfill university and department style requirements; (2) its illustrative materials including figures, tables, and charts are in place; and (3) the final manuscript is satisfactory to the graduate committee and is ready for submission to the university library. ________________________ ____________________________________ Date Phil S. Allen Chair, Graduate Committee Accepted for the Department ____________________________________ Sheldon D. Nelson Department Chair Accepted for the College ____________________________________ Kent D. Crookston Dean, College of Biology and Agriculture ABSTRACT PRESSURIZED HOT WATER: AN ALTERNATIVE METHOD OF ELEMENTAL EXTRACTION AND ANALYSIS FOR USE IN SMALL-SCALE AGRICULTURE Kristy S. Crane Department of Plant and Animal Sciences Master of Science Soil analysis for small acreage farms in developing countries is often inconvenient and prohibitively expensive using current procedures, yet the information gained from these soil tests could have economical and environmental benefits. The pressurized hot-water (PHW) extraction coupled with colorimetric or turbidimetric analyses shows promise as an alternative to current procedures. Accepted methods of colorimetric analysis for NO3-N and P exist but an alternative method to atomic absorption spectrometry for K analysis is needed. Of the many possible methods to quantify K, tests performed in the Brigham Young University (BYU) laboratory found sodium tetraphenylborate to be unsatisfactory and sodium cobaltinitrite to be simple, inexpensive and consistent. Test results on 38 arid-zone soils from the Western United States encourage adoption of sodium cobaltinitrite as an acceptable procedure for K quantification in conjunction with PHW extraction [r2 of 0.90 compared to atomic absorption (AA) analysis and r2 of 0.67 compared to values extracted with ammonium acetate and measured with AA]. Two hundred twenty-eight soils varying widely in soil parameters from different areas of Guatemala and Morocco were analyzed for NO3-N, P and K using standard methods (water-CTA, Olsen-molybdic acid and ammonium acetate- atomic absorption, respectively) and correlated to values obtained from the PHW extraction coupled with colorimetric or turbidimetric analytical procedures at BYU. The correlations between the values for these tests were good (r2 of 0.96, 0.71 and 0.52 for NO3-N, P, and K; respectively). Soils from each country were simultaneously analyzed for NO3-N and P in laboratories in Guatemala and Morocco and these results correlated with those from BYU. Correlations between BYU values and those from other laboratories gave generally positive results with the Guatemala laboratory showing overall closer correlation with BYU values than data from the Morocco laboratory. The results suggest that the PHW extraction and accompanying simplified analyses present a viable, less expensive alternative to current soil nutrient extraction and analysis procedures for the range of soils tested from Morocco and Guatemala. ACKNOWLEDGEMENTS Grateful acknowledgement is given for the guidance, expertise and encouragement of my faculty advisors Dr. Phil Allen and Bruce Webb. Their love of adventure and enthusiasm for science greatly shaped this project and my life. Appreciation is also due Dr. Von Jolley and Dr. Sheldon Nelson for their advice and contributions during the revision phase of this project. Particular thanks are due the Benson Food and Agriculture Institute, the Potash and Phosphate Institute and the Department of Plant and Animal Science at Brigham Young University for financial contributions and acknowledgment must be given to Mustapha Naimi and Hicham at the Institute of Agronomy Hassan II and Gadid Artereaga and Rudolfo Chicas at the University of the East at Cunori. Acknowledgement is in order for Scott Allen, Amanda Silvester, Heather Hunsaker, Darrin Roberts, Jenny Christopherson and Angela Demeester for many hours of laboratory analysis and to Amanda Shiffler and Necia Bair for camaraderie and understanding. I acknowledge my father, Richard Gibson, who introduced me to the joys of plant science as a child and my mother, Lexia Gibson, for her encouragement. I sincerely appreciate my husband, Peter Crane, for the love and support that was crucial to the completion of this project. Finally, I would like to thank my Heavenly Father by whom all things are possible. TABLE OF CONTENTS Title Page…………………………………………………………………………..i Abstract…………………………………………………………………………...iv Acknowledgements………………………………………………………….……vi Table of Contents………………………………………………………………...vii List of Tables………………………………………………………………….......x List of Figures………………………………………………………………….....xi Manuscript 1: A Rapid Turbidimetric Potassium Test Modified for Use with the Pressurized Hot-Water (PHW) Extraction ……………………………………1 Abstract…………………………………………………………………....1 Introduction………………………………………………………………..1 Method Development……………………………………………………...2 Sodium Tetraphenylborate………………………………………...2 Sodium Cobaltinitrite……………………………………………...3 Test of Method……….……………………………………………………5 Results and Discussion…………………………………………………....6 Conclusions………………………………………………………….…….6 References…………………………………………………………………6 Table 1…………………………………………………………………….9 Table 2…………………………………………………………………...10 Table 3…………………………………………………………………...11 Table 4…………………………………………………………………...12 vii Figure 1…………………………………………………………………..13 Figure 2…………………………………………………………………..14 Figure 3…………………………………………………………………..15 Figure 4…………………………………………………………………..16 Manuscript 2: A Simplified Soil Analysis Procedure for Use in Small-Scale Agriculture…………………………………………………………………...17 Abstract…………………………………………………………………..17 Introduction………………………………………………………………17 General…………………………………………………………...17 Phosphorus Extraction…………………………………………...19 Experimental Design……………………………………………………..20 Methods and Materials…………………………………………………...21 PHW Extraction and Analysis…………………………………...21 Standard Methods………………………………………………..21 Analyses Completed at BYU…………………………….21 Analyses Completed in Morocco………………………...21 Analyses Completed in Guatemala………………………21 Results and Discussion…………………………………………………..22 Comparison of Methods………………………………………….22 Comparisons among Laboratories……………………………….23 Conclusions………………………………………………………………24 Acknowledgements………………………………………………………25 References………………………………………………………………..25 viii Table 1…………………………………………………………………...27 Table 2…………………………………………………………………...28 Table 3…………………………………………………………………...29 Table 4…………………………………………………………………...30 Table 5…………………………………………………………………...31 Table 6…………………………………………………………………...32 Figure 1…………………………………………………………………..33 Figure 2…………………………………………………………………..34 Figure 3…………………………………………………………………..35 Figure 4…………………………………………………………………..36 Figure 5………………………………………………………………..…37 Figure 6…………………………………………………………………..38 Appendix I: Introduction and Literature Review………………………………...39 Appendix II: A Summary Table of Spectrophotometric Methods of Analysis for Soil Nutrients………………………………………………………………...44 Appendix III: Methods and Materials…………………………………...…….....70 Appendix IV: Project Data…………………………………………………….....80 ix LIST OF TABLES Manuscript 1: A Rapid Turbidimetric Potassium Test Modified for Use with the Pressurized Hot-Water Extraction Table 1. Transmittance (mean of six readings ± standard deviation) for standard solutions (µg g-1) using the sodium tetraphenylborate method. The standard deviations prove that the test is not sensitive enough at agronomically important soil K values. Values were read on a spectrophotometer at 410 nm.
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