Author
JUNG, WON-KYO - UNIV OF MISSOURI | |
Kitchen, Newell | |
Sudduth, Kenneth - Ken | |
Kremer, Robert | |
MOTAVALLI, ROBERT - UNIV OF MISSOURI | |
ANDERSON, STEPHEN - UNIV OF MISSOURI | |
Alberts, Edward |
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only Publication Acceptance Date: 7/23/2003 Publication Date: 11/3/2003 Citation: JUNG, W., KITCHEN, N.R., SUDDUTH, K.A., KREMER, R.J., MOTAVALLI, R.J., ANDERSON, S.H., ALBERTS, E.E. 2003. SPATIAL CHARACTERISTICS OF SOIL QUALITY INDICATORS ON CLAYPAN SOILS [abstract] [CD-ROM]. ASA-CSSA-SSSA-Annual Meeting Abstracts. Interpretive Summary: Technical Abstract: Site-specific field management practices require an accurate assessment of the spatial structure of soil properties in order to obtain a reasonable estimate at unsampled locations. This research was conducted to understand the spatial characteristics of soil quality indicators on a claypan soil field. Landscape properties, such as elevation and slope, were obtained by real-time kinematic-GPS. Soil samples were collected at three depths (0 to 7.5 cm, 7.5 to 15 cm and 15 to 30 cm) within a 4-ha field on a 10 by 30-m grid spacing (75 samples) and at additional random points (10 samples). Samples were analyzed for physical, chemical, and microbial properties that serve as soil quality indicators. Semi-variogram analysis was used to identify the spatial dependence of soil quality indicators. Spatial dependence of most indicators was unique. Spatial dependence also varied by sampling depth. An exponential model fit to the semi-variograms showed that the variations of CEC, organic C and most physical properties were strongly spatially dependent, with range distances from 20 to 60 m. The range of spatial dependence was greater for the 15- to 30-cm sampling depth than for shallower samples. Our results show that spatial characteristics of soil quality indicators are not the same and tailoring of sampling strategies is required for valid interpolation and mapping. |