|VAN SANTEN, E|
Submitted to: International Soil Tillage Research Organization Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 10/13/2005
Publication Date: 10/13/2005
Citation: Terra, J.A., Shaw, J.N., Reeves, D.W., Van Santen, E., Raper, R.L., Balkcom, K.S., Schwab, E.B. 2005. Soil management practices and landscape attributes impacts on field-scale corn productivity. In: Proceedings of the 16th International Soil Tillage Research Organization (ISTRO) Conference, July 13-18, 2003, Brisbane, Australia. p. 1217-1222. CD-ROM.
Technical Abstract: Soil management practices and terrain attributes effects on corn (Zea mays L.) grain yield were assessed in a 9-ha Alabama field (Typic and Aquic Paleudults) during 2001-2004. A conventional system (chisel plowing/disking with no cover crops) with or without dairy manure (CTmanure or CT), and a conservation system (no-till and winter cover crops) with and without manure (NTmanure or NT), were established in strips traversing the landscape in a corn-cotton (Gossypium hirsutum L.) rotation. Five management zone clusters were delineated using a soil survey, topography and surfaces of soil electrical conductivity (EC), soil organic carbon (SOC) and soil texture. Conservation systems had greater yield than conventional systems in all clusters in 2002 (dry season; 8.88 vs. 6.71 Mg ha-1), and in four of five clusters in 2003 (wet season; 13.04 vs. 12.33 Mg ha-1); no differences existed in 2001 (9.85 Mg ha-1) . In 2004, CT (8.43 Mg ha-1) had the lowest yield in all clusters; NTmanure (11.21 Mg ha-1) had greater yield than NT and CTmanure (10.57 and 10.30 Mg ha-1 respectively) in some clusters. Yield differences between high and low productivity clusters within years were lower in conservation than in conventional systems. Soil texture, SOC and EC were typically related with yield in all treatments, and explained 47-71 % of yield variation. Factor analysis suggested that soil degradation and field-scale water dynamics had significant impacts on yield variability. The aggregate of data indicates for degraded soils in warm humid climates, conservation systems increase corn productivity and spatial and temporal stability of yields even during initial adoption years.