|Van Santen, Edzard|
Submitted to: Southern Conservation Agricultural Systems Conference
Publication Type: Proceedings
Publication Acceptance Date: 6/25/2007
Publication Date: 6/25/2007
Citation: Biscaro, A.S., Arriaga, F.J., Balkcom, K.S., Shaw, J.N., Van Santen, E., Bergtold, J.S., Raper, R.L., Reeves, D.W. 2007. Assessment of soil physical properties on different management practices and landscape positions. In: Wright, D.L., Marois, J.J., Scanlon, K., editors. Proceedings of the 29th Southern Conservation Agricultural Systems Conference, June 25-27, 2007, Quincy, Florida. Available at: http://www.ag.auburn.edu/auxiliary/nsdl/scasc/. Interpretive Summary: Understanding field variability of soil properties can help producers optimize inputs and increase profitability. Additionally, this knowledge can help protect the environment due to enhanced fertilizer and pesticide use. The impact of four crop management practices and field variability was evaluated on a large field in the central Alabama Coastal Plain. The field was divided into three major areas by the difference in elevation. The four management practices were: 1) conventional tillage with manure; 2) conventional tillage without manure; 3) conservation tillage with manure; 4) conservation tillage without manure. A corn-cotton rotation was evaluated for this research. Overall, water movement, soil stability and soil carbon content were lower with conventional tillage. Manure application increased soil carbon content regardless of tillage treatment. Carbon content increased by 62% with manure application on conventional tillage treatments and by 39% on conservation tillage. However, soil carbon content was greater on conservation tillage than conventional tillage treatments. Water movement was greatest on higher elevations in the field. No differences were found for soil stability and carbon content with elevation. Conservation tillage for 6 crop years thus far has improved soil quality more than manure application alone. Continued efforts on this work will help producers manage their lands more efficiently.
Technical Abstract: Crop production has become more costly every year, and improving recommendations and implementation of site-specific crop management can help farmers achieve input optimization and consequent savings. The use of precision agriculture techniques is completely dependent on understanding the spatial variability of soil physical properties. In order to assess management practices and landscape variability effects on soil physical properties, infiltration, aggregate stability and total carbon (C) were measured in a 22 acre field in the central Alabama Coastal Plain. Based on the local soil properties, the field was separated into three zones - summit, backslope and accumulation. Four tillage systems treatments - conventional system with (CT+M) or without (CT) dairy manure, and conservation system with (NT+M) or without (NT) dairy manure - and corn-cotton rotation have been established in the study area since 2001. Overall, infiltration, aggregate stability and C content were lower in CT. The C content was significantly higher (P < 0.001) for treatments with manure, where CT+M was 62% greater than CT, and NT+M was 39% greater than NT. Infiltration was highest on the summit (5.7 in/h), followed by backslope and accumulation zones (3.4 and 2.8 in/h, respectively). No significant difference (P = 0.69 and 0.39, respectively) was found for aggregate stability and carbon among the zones. Conservation tillage for 6 crop years thus far has improved