Residue Level and Manure Application Timing Effects on Runoff and Sediment Losses

Abstract

There is growing interest in evaluating the effects of corn silage harvesting methods on erosion control. Increasing the silage cutting height will increase residue cover and could conceivably minimize off-site migration of sediments compared with conventional silage harvesting. The effects of residue level and manure application timing on runoff and sediment losses from no-till corn were examined. Treatments included conventional corn grain (G) and silage (SL) and nonconventional, high-cut (60-65 cm) silage (SH). Corn harvesting treatments were subjected to different manure application regimes: no manure (N) or surface application in fall (F) or spring (S). Simulated rainfall (76 mm/h; 1 h) was applied in spring and fall for two years (2002-2003), runoff from 2.0- x 1.5-m plots collected, and a subsample analyzed for sediment concentration and aggregate size distribution. Runoff volume was inversely related to residue cover. Manure addition to silage plots reduced spring runoff by 71 to 88%, attributable to an increase in soil organic matter content, compared with SH-N and SL-N. Differences in sediment concentration between SH and SL were not significant. For silage plots, spring-applied manure had the greatest influence on sediment export reducing it by 84 to 93% in spring runoff compared with corresponding N plots. Sediment loads were also 85 to 97% lower from SH-S compared with SL-N in all four seasons. Except for spring 2003, sediment export was lower from G compared with SL. The combination of manure and higher residue associated with high-cut silage often lowered sediment export compared with low-cut silage. Nearly identical aggregate size distributions were observed in sediments from SH and SL plots. High residue levels combined with spring-applied manure led to enrichment in the clay-sized fraction of runoff sediment. Recently applied manure and higher residue levels achieved by high-cutting silage can substantially lower sediment losses in spring runoff when soil is most susceptible to erosion.

Delayed Tillage and Cover Crop Effects in Potato Systems

“…In contrast, delaying primary tillage until just prior to potato planting consistently resulted in ground cover in excess of 90%. As shown by Grande et al (2005), there is a curvilinear relationship between residue cover and sediment load under erosive conditions; when there is little ground cover (20% or less), small increases result in a disproportionate reduction in sediment loss. Once ground cover of more than 50% is achieved, sediment losses may be reduced by 90% or more, compared to bare soil or minimally covered soil.…”

Soil Erosion by Water

“…Manuring can reduce water runoff by 70-90 % and sediment loss by 80-95 % as a result of increased organic matter content (Grande et al 2005 ). Using manure in combination with other conservation practices, such as no-till may be an effective strategy for reducing soil erosion.…”

Phosphorus and organic matter enrichment in snowmelt and rainfall–runoff from three corn management systems

“…Elevated residue levels have been found to decrease detachment and reduce overland flow velocity, in-turn causing larger particles to settle, thus promoting transport of Penriched finer particles (Pierzynski et al, 1990). Higher residue levels have also been shown to help maintain higher average infiltration rates and surface roughness that also facilitate particle deposition (Baker and Laflen, 1982;Grande et al, 2005), resulting in greater P enrichment. The highest TP ER values occurred during May, with the lowest values during the high soil loss events of June.…”