Soil property and soybean yield trends in response to alternative wheat residue management practices in a wheat-soybean, double-crop production system in eastern Arkansas
Loading...
Date
2008
Authors
Amuri, Nyambilila
Brye, Kristofor R
Gbur, Edward E
Popp, Jennie
Chen, Pengyin
Journal Title
Journal ISSN
Volume Title
Publisher
Electronic Journal of Integrative Biosciences
Abstract
Growing concerns over the long-term sustainability of agricultural
systems require investigation of agricultural management practices
that may improve and sustain soil quality and crop productivity
over time. Over 20% of the soybean [Glycine max (L.) Merr.] area
in the highly productive Mississippi River Delta region of the mid southern United States is in a double-crop rotation with wheat
[Triticum aestivum (L.)]. Currently, much of the resulting wheat
residue is managed by burning followed by conventional tillage,
but this combination may not be environmentally sustainable.
Therefore, the objective of this study was to determine the long term effects of tillage [conventional (CT) and no-tillage (NT)],
wheat-residue burning (burn and no burn), wheat-residue level
(low and high, achieved with differential N fertilization), and
irrigation (irrigated and dry-land) on soybean yield, net economic
returns, and soil properties in the top 10 cm of a wheat -soybean,
double-crop production system. A field experiment was conducted
from 2001 through 2007 in the Mississippi River Delta region of
eastern Arkansas on a Calloway silt loam (fine silty, mixed, active,
thermic Glossaquic Fraglossudalf). Soil bulk density increased in
both CT and NT during the first three years, but at a greater rate
under NT (0.12 g cm-3 yr-1) than CT (0.08 g cm-3 yr-1), followed by
a decline at a similar rate in both tillage treatments. Soil pH and
Mehlich-3 extractable soil Ca and Mg contents increased, while
electrical conductivity decreased linearly over time when all
treatments were combined. Soil organic matter (SOM) increased
over time in all treatment combinations. Total C (TC) increased at
a greater rate in the no burn (0.08 kg C m-2 yr-1) and high-residue level (0.07 kg C m-2 yr-1) than in the burn (0.05 kg C m-2 yr-1) and
low-residue-level (0.05 kg C m-2 yr-1) treatments. Extractable soil
P content declined linearly over time at greater rate under NT (3.3
kg P ha-1 yr-1) and high-residue-level (3.4 kg P ha-1 yr-1) than under
CT (2.6 kg P ha-1 yr-1) and low-residue-level (2.4 kg P ha-1 yr-1)
treatments. Soybean yield declined at a similar rate in the first
three years, but increased at a similar rate over the subsequent
three years in all tillage-treatment combinations. Increasing SOM
and TC over time indicated that the silt-loam soils of the
Mississippi River Delta region have the potential to accumulate C
in the top 10 cm at increasing rates beyond six years from initial
conversion to alternative residue management practices.
Implementation of the appropriate residue management practices
has the potential to improve soil quality and maintain long-term
productivity of silt-loam soils in the Mississippi River Delta region
of the mid-southern United States.
Description
Journal Article
Keywords
Arkansas, Organic matter, Residue management, Wheat, Soybean, Soil properties, Soil carbon