| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
a Dep. of Geological Sciences, Univ. of Tennessee, Knoxville, TN 37996-1410
b Département des Sols et de Génie agro-alimentaire, Université Laval, Pavillon Comtois, Sainte-Foy, PQ, Canada G1K 7P4
* Corresponding author (eperfect{at}utk.edu)
Tillage research has traditionally focused on mean effects; few studies have compared treatments in terms of their spatial variability. We applied several methods of time-space series analysis to investigate the spatial variability of gravimetric water content (w), volumetric water content (
), bulk density (
b) and total C (TC) in the upper 10 cm of long-term conventional-till (CT) and no-till (NT) soil management practices at Lexington, KY. The soil was a Maury silt loam (fine, mixed, semiactive, mesic Typic Paleudalf). Replicate transects were established in untracked interrows parallel to the direction of tillage in the CT practice. Each transect was 48.5 m long with 107 equally spaced sampling points. Soil spatial variability was higher under NT than under CT. Spectral analyses of variance identified significant differences between tillage treatments at frequencies <0.02 cycles m-1 for all soil properties, and at 0.18 cycles m-1 for w, 0.13, 0.31 and 0.48 cycles m-1 for , and 0.22, 0.70 and 0.90 cycles m-1 for b. Spatial variations in water content and b appeared to be related to the distribution of TC. Coherency analysis indicated relationships were strongest at frequencies <0.09 cycles m-1. For NT the relationship between w and TC was also significant at higher frequencies (1.01–1.05 cycles m-1). Gravimetric water content increased as TC increased, while and b decreased. Lagged relations for w versus TC were more frequent in CT than NT, possibly due to soil translocation during tillage operations. The opposite was true for versus TC and b versus TC, suggesting that soil aggregates form at some distance from sites of carbon deposition under NT.
Abbreviations: CT, conventional tillage soil management practice • CV, coefficient of variation • DFT, discrete Fourier transform • NT, no-till soil management practice • TC, total C content • TDR, time domain reflectometry • w, gravimetric water content • , volumetric water content • b, bulk density
This article has been cited by other articles:
|
|
 |
|
  B. C. Si Spatial Scaling Analyses of Soil Physical Properties: A Review of Spectral and Wavelet Methods Vadose Zone J., May 27, 2008; 7(2): 547 - 562. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. J. Munkholm, E. Perfect, and J. Grove Incorporation of Water Content in the Weibull Model for Soil Aggregate Strength Soil Sci. Soc. Am. J., April 5, 2007; 71(3): 682 - 691. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. N. Kravchenko, G. P. Robertson, X. Hao, and D. G. Bullock Management Practice Effects on Surface Total Carbon: Differences in Spatial Variability Patterns Agron. J., October 3, 2006; 98(6): 1559 - 1568. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Perie, A. D. Munson, and J. Caron Use of Spectral Analysis to Detect Changes in Spatial Variability of Forest Floor Properties Soil Sci. Soc. Am. J., February 2, 2006; 70(2): 439 - 447. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. N. Kravchenko, G. P. Robertson, K. D. Thelen, and R. R. Harwood Management, Topographical, and Weather Effects on Spatial Variability of Crop Grain Yields Agron. J., March 1, 2005; 97(2): 514 - 523. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Perfect, A. B. Kenst, M. Diaz-Zorita, and J. H. Grove Fractal Analysis of Soil Water Desorption Data Collected on Disturbed Samples with Water Activity Meters Soil Sci. Soc. Am. J., July 1, 2004; 68(4): 1177 - 1184. [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 | ||||
| Journal of Plant Registrations | Journal of Environmental Quality |
The Plant Genome | |||
