Submitted to: Agronomy Journal
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/31/2013
Publication Date: 12/13/2013
Publication URL: http://handle.nal.usda.gov/10113/59381
Citation: Mikha, M.M., Benjamin, J.G., Stahlman, P.W., Geier, P.W. 2013. Remediation/restoration of degraded soil I: Impact on soil chemical properties. Agronomy Journal. 106:252-260. Interpretive Summary: In the central Great Plain Region, it is critical to characterize the nutrient dynamics of eroded land as affected by tillage and manure addition. Six years of data, 2006 to 2011, were collected from the eroded site located at the Agricultural Research Center, near Hays, KS. The eroded study site exhibits low soil nutrient content and high alkalinity. This was due to top soil losses, particularly by wind erosion. The addition of high dosage of manure, double the crop nitrogen requirement, reduces soil alkalinity by 21% compared with the same amount of commercial fertilizer at the surface 6 inches. Soil extractable phosphorus (P) with a high dosage of manure was increased by 28 ppm than the low dosage of manure, equivalent to crop N requirement. In general, six years of annual manure addition as N source improved soil nutrient dynamics in this eroded site compared with commercial fertilizer.
Technical Abstract: Characterizations of nutrient dynamics influenced by different management in eroded sites in the central Great Plains Region are critical. The objectives of this study were to evaluate the impact of tillage practices and N treatments on changes in soil nutrient constituents. The eroded site was located at the Kansas State University Agricultural Research Center near Hays, KS. Soil type was an Armo silt loam (fine-loamy, mixed, mesic, Entic Haplustolls). Treatments were two tillage practices, no-tillage (NT) and conventional tillage (CT); two nitrogen (N) sources, beef manure (M) and urea as commercial fertilizer (F) at low (L) and high (H) N rates. The control (C) treatment, with no N added, was included under both tillage practices. Soil samples were taken annually in the spring at 0- to 15-cm and 15- to 30-cm depths. The treatments were arranged as a randomized complete block design with four replicates. Soil chemical properties were influenced by treatment combinations of N source and rate and sampling depths, but not by tillage. Soil acidity (pH) was reduced in 2011 compared with 2006. Relative to control, more reduction in soil pH was observed with MH (21%) compared with FH treatment. Soil EC with MH and FH was approximately 2.2 times greater than ML and FL. Soil Olsen (NaHCO3) extractable phosphorus (P) with MH substantially increased, 45.9 mg kg-1, compared with ML, 18.3 mg kg-1, at the surface 0- to 15-cm. In general, the use of M as nitrogen source improved soil nutrient dynamics in this eroded site compared with F.