| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
a USDA-ARS, U.S. Dairy Forage Research Center, 1925 Linden Drive West, Madison, WI 53706
b USDA-ARS, Pasture Systems and Watershed Management Research Unit, Building 3702, Curtin Road, University Park, PA 16802-3702
* Corresponding author (vadas{at}wisc.edu)
Received for publication September 1, 2005. Manure water-extractable phosphorus (WEP) data are used in indices and models to assess P transport in runoff. Methods to measure WEP vary widely, often without understanding the effect on how much P is extracted. We conducted water extractions on five dairy, swine, and poultry manures to assess single and sequential extractions, drying manures, solution to solid (cm3 g–1) extraction ratios, and P determination method. We found little difference in WEP of single or sequential extractions. Increasing extraction ratio from 10:1 to 250:1 resulted in more WEP recovered, but in a diminishing fashion so that ratios of 200:1 and 250:1 were not significantly different. Patterns of increased WEP with extraction ratio varied with manure type, presence of bedding material, and drying treatment. Fresh and air-dried manures had similar patterns, but differed substantially from oven-dried (90°C) manures. The differential effect of oven-drying on WEP was greatest for dairy and poultry manure, and less for swine manure. We analyzed water extracts colorimetrically before and after digestion, to examine the potential effect of P determination by inductively coupled plasma (ICP) spectroscopy. Digested extracts always contained more P. For manures with bedding, drying decreased the difference in P measured before and after digestion. The opposite was true for manures without bedding. Results highlight the influence of methodology on manure WEP measurement and caution needed when comparing data across studies using different WEP methods. Overall, our results point to a need for a standard manure water extraction method.
Abbreviations: ICP, phosphorus analysis by inductively coupled plasma spectroscopy • TP, total phosphorus in manures • WEP, manure water-extractable phosphorus • WEPI, inorganic manure water-extractable phosphorus measured colorimetrically without digestion • WEPT, total manure water-extractable phosphorus measured colorimetrically with digestion
This article has been cited by other articles:
|
|
 |
|
  U. P. P. Pillai, V. Manoharan, A. Lisle, X. Li, and W. Bryden Phytase Supplemented Poultry Diets Affect Soluble Phosphorus and Nitrogen in Manure and Manure-amended Soil J. Environ. Qual., June 23, 2009; 38(4): 1700 - 1708. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. P. Hanrahan, W. E. Jokela, and J. R. Knapp Dairy Diet Phosphorus and Rainfall Timing Effects on Runoff Phosphorus from Land-Applied Manure J. Environ. Qual., January 13, 2009; 38(1): 212 - 217. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Z. He, B. J. Cade-Menun, G. S. Toor, A.-M. Fortuna, C. W. Honeycutt, and J. T. Sims Comparison of Phosphorus Forms in Wet and Dried Animal Manures by Solution Phosphorus-31 Nuclear Magnetic Resonance Spectroscopy and Enzymatic Hydrolysis J. Environ. Qual., May 25, 2007; 36(4): 1086 - 1095. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. A. Vadas, W. J. Gburek, A. N. Sharpley, P. J. A. Kleinman, P. A. Moore Jr., M. L. Cabrera, and R. D. Harmel A Model for Phosphorus Transformation and Runoff Loss for Surface-Applied Manures J. Environ. Qual., January 9, 2007; 36(1): 324 - 332. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Crop Science | |||
| Journal of Natural Resources and Life Sciences Education |
Vadose Zone Journal | ||||
| Soil Science Society of America Journal | Journal of Plant Registrations | The Plant Genome | |||
