Abstracts

277 - Assessing soil water content & temperature under
conventional tillage & no-tillage for drought adaptation
G.Y. Suarez 1 , P. von Bertoldi 2 , D. Rudolph 1 & G. Parkin 2
1
Department of Earth and Environmental Sciences – University of Waterloo, Waterloo,
Ontario, Canada
2
School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada
Pre-growing season weather forecasts are relatively unreliable and farmers must seek an
alternative measure to inform their land management options in order to reduce the potential
impact of drought on crop yield. A potential approach to minimizing drought impacts
is to use measured or modelled soil water storage and temperature in late spring as
a predictor of future dry soil conditions. This information can then be used to modify the
planting date to reduce the impacts of a subsequent dry growing season and to ensure
optimal temperature conditions for crop growth. Both parameters may be influenced by
the tillage methods adopted on the fields. High resolution (hourly) soil water content and
temperature data collected at a research farm for 11 years within the 0–100 cm depth profiles
under no-till (NT) and conventional fall tillage (CT) practices were used to test the
hypothesis that no-tillage reduces the impact of drought on crop yield by conserving soil
water storage while maintaining optimum soil temperature during the growing season in
comparison to conventional tillage. The field data sets were used in a time series analysis
with a forecasting model to understand field data behaviour and predict the ideal planting
date to avoid potential impacts of drought on crop yield. The results indicate that adopting
a no-till management system may be one strategy of reducing the impact of drought by
conserving more soil moisture and temperature than tilled soil. Also the soil temperature
autoregression forecasting model using precipitation and air temperature as correlated data
shows high certainty and accuracy for predicting soil temperature. The forecast model can
be useful for predicting optimum planting date.
205 - Modelling nitrate concentrations in the shallow subsurface
for variable hydrogeological settings in agricultural watersheds
Shoaib Saleem, Jana Levison, Beth Parker, Nishant Mistry & Scott Gardner
School of Engineering – University of Guelph, Guelph, Ontario, Canada
Ralph Martin
Plant Agriculture – University of Guelph, Guelph, Ontario, Canada
Groundwater is the principle source of water for about 30% of population in Ontario
and most families living in rural areas entirely depend on it for their water supply. Advancements
in agricultural technologies have increased farm productivity and profitability.
However, associated intensive nitrogen application in agricultural fields has also resulted in
leaching of excess nitrogen to aquifers in a variety of settings. Elevated nitrate in drinking
water is a concern since it can lead to various health issues such as methemoglobinemia
(blue-baby syndrome). The maximum allowable limit for nitrate in Canadian drinking
water is 10 mg L -1 nitrate-N. Therefore, it is very important to have a comprehensive
understanding of evolving cropping systems and their potential impact on groundwater
84 IAH-CNC 2015 WATERLOO CONFERENCE