『Abstract
The objective of this study was to examine the interactive effects
of tillage and land forms (erodibility) on the redistribution
of C, N and P within an agricultural landscape. soils were sampled
from an undulating maize field in central Belgium. Half of the
field was under conventional tillage (CT), while the rest was
under minimum tillage (MT) management. Based on slope and curvature
characteristics, depositional and erodible zones were identified
in both tillage treatments. We analyzed 400 surface (0-5 cm) soil
samples, and 25 soil profiles (0-100 cm). Concentrations of native
C, maize-derived C, total N, Olsen P, and moisture content in
the 0-5 cm soil layer showed distinct spatial patterns with variogram
ranges from 30 to 90 m. These patterns were related to local differences
in texture and landform. In general, nutrient concentrations were
greater in lower, depositional areas, and smaller in higher, erodible
areas. In addition, the impact of landform was more pronounced
in CT than MT. Three years after the implementation of the tillage
treatments, native C, total N and Olsen P stocks (0-46 cm) in
erodible zones were about 40% less under CT than under MT. However,
in depositional zones, nutrient stocks were equal between the
tillage treatments. Differences in erosion rates, the distribution
of Olsen P and maize-derived C indicated that this pattern was
mainly caused by soil transport induced by erosion since the implementation
of the tillage treatments, rather than local differences in decomposition
rates. We concluded that the influence of landforms on the stabilization
and redistribution processes of nutrients is greater within CT
than MT. Therefore, interactions between landform and agricultural
management need to be considered in regional soil organic matter
inventory assessments
Keywords: Erosion; Deposition; Tillage; Agriculture; Carbon; Soil
nutrients』
1. Introduction
2. Materials and methods
2.1. Site description
2.2. Soil sampling
2.3. Analyses
2.4. Statistical analyses
3. Results
3.1. Native C, maize-derived C, Olsen P, and moisture content
in surface samples across the field
3.2. Surface C, N, P, moisture and bulk density across curvature
classes
3.3. Nutrient stocks
3.4. Depth profiles of native C, maize-derived C and Olsen P
4. Discussion
5. Conclusions
Acknowledgements
Appendix A. Supplementary data
References