|
|
||||||||
a USDA-ARS, Dairy Forage Research Center, 1925 Linden Dr. West, Madison, WI 53706
b Dep. of Soil Science, Univ. of Wisconsin, 1525 Observatory Dr., Madison, WI 53706
* Corresponding author (jmpowel2{at}wisc.edu)
Received for publication May 19, 2004. Indirect estimates of manure N availability to crops are highly variable. We developed two methods that label dairy manure N components with the stable isotope 15N for direct measurement of manure N availability to crops. The forage method involved the labeling then feeding of 15N-enriched forage to dairy cows (Bos taurus) to label urine N, fecal endogenous N, and fecal undigested feed N. The urea method involved the direct feeding of 15N-enriched urea to label urine N and fecal endogenous N. Manure from each enrichment method was applied to a Plano silt loam (fine-silty, mixed, mesic, Typic Argiudolls) using field plots in 1999 and 2000; corn (Zea mays L.) was grown for 2 yr after each application. No significant differences were observed in manure 15N recoveries in corn, soil inorganic N, or soil total N due to manure application year or manure enrichment method. Corn took up 14 to 16% of manure 15N the first year and 4 to 8% the second year after application. Most 15N recovery in soil inorganic and total N was found in the upper 30 cm of soil, indicating little downward movement of applied manure 15N. On average, 68% of applied manure 15N was accounted for, either in crop uptake (21%) or in the soil (47%). The less laborious and less costly urea enrichment method may be adequate for short-term (2 yr or less, the range of this study) manuresoilcropN cycling studies. Longer-term studies may need to include fecal undigested feed 15N derived from the forage enrichment method.
Abbreviations: FM, forage manure MEM, manure enrichment method UM, urea manure
This article has been cited by other articles:
![]() |
P. R. Cusick, K. A. Kelling, J. M. Powell, and G. R. Munoz Estimates of Residual Dairy Manure Nitrogen Availability Using Various Techniques J. Environ. Qual., October 27, 2006; 35(6): 2170 - 2177. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Zhang, R. Gavlak, A. Mitchell, and S. Sparrow Solid and Liquid Cattle Manure Application in a Subarctic Soil: Bromegrass and Oat Production and Soil Properties Agron. J., October 3, 2006; 98(6): 1551 - 1558. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Crop Science | Vadose Zone Journal | |||
| Journal of Natural Resources and Life Sciences Education |
Soil Science Society of America Journal | ||||
| Journal of Plant Registrations | Journal of Environmental Quality |
The Plant Genome | |||