Soil Properties, Soybean Response, and Economic Return as Affected by Residue and Water Management Practices

Abstract

Soil, water, and air quality can be positively impacted by alternative crop residue management practices that return residue to the soil. Double-crop production systems, particularly those with a grass included in the rotation, rely on successful residue management practices. Soil quality and overall soil tilth are often low in regions with a long history of intensely cultivated, row-crop production, such as in the Mississippi River Delta region of the mid-South. Therefore, the objective of this study was to evaluate the effects of alternative residue (i.e., tillage, residue burning, and residue level) and water management practices on soil properties, soybean [Glycine max (L.) Merr.] production, and net economic returns, over two consecutive rotations in a wheat (Triticum aestivum L.)-soybean double-crop system in the Mississippi River Delta region of eastern Arkansas. Initiated in 2001, this study reports results from years 4 and 5 of the experiment. Residue management effects were inconsistent among soil properties and years, and differences were generally agronomically non-significant. Averaged across irrigation treatments, soybean yield was unaffected by tillage, burning, and residue level either year. Within the non-irrigated treatment, conventionally tilled (CT) soybean yield was 38 % greater (p < .05) than no-tillage (NT) in 2005, but similar in 2006. In 2005 and 2006, irrigated soybean yield was 34 and 26 % greater (p < .05), respectively, in the burned than non-burned treatment. In 2006, the estimated net return from the high residue/burned/NT/irrigated Management Practice Effects on Soil and Crop Response 717treatment combination was 51 % greater than the traditional combination of high residue/burned/CT/irrigated soybean. By years four and five following conversion from CT to NT, the more environmentally sustainable practice of NT appears to be a viable, and potentially more profitable, alternative to the traditional and common practice of CT.

Wheat (Triticum aestivumL.) Cultivar Selection Affects Double-Crop and Relay-Intercrop Soybean (Glycine maxL.) Response on Claypan Soils

“…Soybean plant population at harvest was lower when Ernie was seeded in 38-cm rows, possibly because the amount of residue in the field affected available soil moisture for soybean plants [41]; but there was no effect of wheat row spacing on double-crop soybean grain yield. Similarly, wheat residue management had no effect on double-crop soybean yield in eastern Arkansas [41].…”

Carbon Dioxide Emissions as Affected by Alternative Long-Term Irrigation and Tillage Management Practices in the Lower Mississippi River Valley

“…When biological consumption of soil organic matter is limited, soil C can build up in the soil. Although plant productivity may be limited in dry years, dryland agriculture can have both economic and environmental benefits [ 29 ].…”

“…Parsch et al [ 31 ] reported that nonirrigated soybean grown in eastern Arkansas generally provided a larger net economic return for the producer than irrigated soybean. Verkler et al [ 29 ] also demonstrated that, during a favorable rainfall year, dryland soybean production was equally profitable as irrigated soybean production in eastern Arkansas. However, not surprisingly, during growing seasons of less-than-optimal rainfall, dryland production was much less profitable than irrigated soybean production.…”

Long-Term Effects of Alternative Residue Management Practices on Soil Water Retention in a Wheat-Soybean, Double-Crop System in Eastern Arkansas

“…Consistent with prior annual soil sampling conducted at this field site [6] [7] [14] [16], at wheat harvest in May 2014, a single soil sample was collected from the top 10 cm in each plot using a 4.8-cm-diameter stainless steel core chamber beveled to the outside to minimize compaction. Soil samples were oven-dried for 48 hr at 70˚C, weighed for bulk density determinations, ground to pass through a 2-mm mesh screen, and analyzed for selected soil chemical properties.…”

“…In addition, to determine actual residue management effects on near-surface bulk density, a third set of soil cores were collected between 8 and 10 weeks after soybean planting in 2014, similar to previous annual bulk densities assessments [6] [7] [14] [16]. A single 4.8-cm-diameter soil core was extracted from the top 10 cm in each plot using a stainless steel core chamber and slidehammer.…”