|SCHLEGEL, ALAN - Kansas State University|
|Baumhardt, Roland - Louis|
|Evett, Steven - Steve|
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 8/19/2013
Publication Date: 11/3/2013
Citation: Schwartz, R.C., Schlegel, A.J., Baumhardt, R.L., Evett, S.R., Bell, J.M. 2013. Contrasting tillage effects of infiltration, stored soil water and yield at two locations [abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. Session 182-3, p. 119.
Technical Abstract: The success of reduced tillage practices in improving and sustaining crop yield can be influenced by the interaction of soil and climate. A parallel field study in Bushland, TX and Tribune, KS evaluated infiltration and evaporation throughout a wheat-sorghum-fallow rotation under no tillage (NT) and stubble-mulch tillage (ST) management. Near-surface (0.1 – 0.3 m) hourly soil water contents were measured at each location using time-domain reflectometry. Profile water contents were monitored weekly or bi-weekly using a neutron probe. Soil temperature, precipitation and solar radiation were also measured. Cumulative infiltration and evaporation were estimated using a water balance approach in conjunction with a calibrated drainage model. At both locations, soil water contents at 0.05 and 0.1 m were lower in recently tilled ST plots compared with NT plots, even following repeated precipitation events. Prior to sorghum emergence, tillage reduced pre-emergence water content by 7 mm in Bushland and 60 mm in Tribune. Most of the additional stored soil water under NT was above 0.15 m depth at both locations. During fallow after sorghum in Bushland, NT did not influence cumulative infiltration and evaporation and, consequently, did not exhibit significantly improved water storage, despite having greater residue cover. During fallow after sorghum in Tribune, NT significantly (P less than 0.06) increased infiltration compared with ST but these gains were offset by greater evaporation rates. Field areas with high residue accumulations and differing micro-elevations likely contributed to the large variability in infiltration fluxes for NT at both locations. The short-term hydrologic response to tillage practices substantially differs at each location, and this influences sorghum yield potential, and profitable dryland cropping management practices at each location.