Skip to main content
ARS Home » Southeast Area » Tifton, Georgia » Southeast Watershed Research » Research » Publications at this Location » Publication #156541
Title: TILLAGE EFFECTS ON INTERRILL ERODIBILITY OF HIGHLY-WEATHERED SOUTHEASTERN SOILS

Author
item Truman, Clinton
item Reeves, Donald
item SHAW, JOEY - AUBURN UNIV

Submitted to: Soil Science Society of America Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/11/2003
Publication Date: N/A
Citation: N/A

Interpretive Summary: Soils of the Southeastern U.S. have been traditionally conventional tilled and are considered highly erodible. Conservation tillage systems are effective BMPs to reduce soil loss. We quantified differences in infiltration, runoff, soil loss, and calculated interrill erodibilities (Ki) for three soils with the following surface textures: loamy sand (AL), silt loam (AL), and loamy sand (GA) managed under conventional- (CT), strip- (ST), and no-till (NT) systems with and without surface cover (C, NC) and/or with and without paratilling (+P, -P). Field plots (1-3% slope, 1-m2) established on each treatment received simulated rainfall (50 mm h-1 for 2 h). Infiltration, runoff, soil loss and subsequent Ki value differences among tillage systems were attributed to the presence or absence of surface residue cover and/or paratilling. Surface residue cover increased infiltration and decreased runoff by 16% to 1.5-fold and decreased soil loss by 3- to 5-fold. Paratilling increased infiltration and decreased runoff (by 12% to 7-fold) and decreased soil loss (62% to 3-fold). Surface residue cover and paratilling caused a 2- to 3-fold decrease in Ki (Ki values ranged from 0.01-0.40). The worst-case scenario evaluated in terms of infiltration, runoff, soil loss and Ki values was the CT-P, NC treatment, whereas the best-case scenarios were the NT+P, C and ST-P, C treatments. Reduced tillage systems (NT, ST) coupled with surface residue cover and/or paratilling are effective BMPs for reducing runoff and soil loss and lowering Ki.

Technical Abstract: Soils of the Southeastern U.S. have been traditionally conventional tilled and are considered highly erodible. Conservation tillage systems are effective BMPs to reduce soil loss. We quantified differences in infiltration, runoff, soil loss, and calculated interrill erodibilities (Ki) for three soils with the following surface textures: loamy sand (AL), silt loam (AL), and loamy sand (GA) managed under conventional- (CT), strip- (ST), and no-till (NT) systems with and without surface cover (C, NC) and/or with and without paratilling (+P, -P). Field plots (1-3% slope, 1-m2) established on each treatment received simulated rainfall (50 mm h-1 for 2 h), and runoff and soil loss were measured continuously. Infiltration, runoff, soil loss and subsequent Ki value differences among tillage systems were attributed to the presence or absence of surface residue cover and/or paratilling. NT, C and ST, C plots increased infiltration and decreased runoff by 16% to 1.5-fold and decreased soil loss by 3- to 5-fold compared to corresponding NC plots. NT+P plots were less dense (by ~ 10%) resulting in increased infiltration and decreased runoff (by 12% to 7-fold) and decreased soil loss (62% to 3-fold) compared to NT-P plots. Surface residue cover and paratilling caused a 2- to 3-fold decrease in Ki (Ki values ranged from 0.01-0.40). The worst-case scenario evaluated in terms of infiltration, runoff, soil loss and Ki values was the CT-P, NC treatment, whereas the best-case scenarios were the NT+P, C and ST-P, C treatments. Reduced tillage systems (NT, ST) coupled with surface residue cover and/or paratilling are effective practices for reducing runoff and soil loss and lowering Ki.