Soil dynamics driven by controlled traffic farming in the Canadian Prairies

  • Author / Creator
    Guenette, Kris G.
  • Growth of the human population within the next half century is projected to reach a staggering quantity. Maintaining our food security for future generations without causing further environmental degradation in an ever dynamic landscape is a complex challenge, which may be partially remedied through the application of practices that promote sustainability in the agricultural industry. The implementation of controlled traffic farming (CTF), a management system which reduces spatially applied compaction, is a doorway to reach sustainability as it can reduce soil degradation and facilitate soil amelioration. As soil degradation from conventional agricultural practices may greatly hinder our food production ability, any means of mitigating the risk in achieving future food security must be rigorously studied. Thus, it was the goal of this study to analyze how the implementation of CTF impacts soil and its respective quality in the Canadian Prairies. This was achieved through: (i) a regional analysis of how CTF affects soil physical quality in annual croplands throughout Alberta, Canada, (ii) investigating how simulated CTF field conditions impact the water use of faba beans (Vicia faba L.) and (iii) assessing how CTF influences the spatial heterogeneity of soil quality at the field scale in Alberta, Canada. The findings of this study revealed how the implementation of CTF can have variable effects on different soils throughout Alberta, Canada due to intrinsic and extrinsic influencing factors (i.e., the landscape under examination, the duration of CTF usage and the management practices previously employed). However, despite site specific variability influencing CTF responses, soil physical quality was found to greatly benefit the un-trafficked areas of CTF, which can potentially represent a maximum of 80% of the field area from CTF implementation. Further investigation into the interaction of faba beans with soil conditions experienced in CTF fields throughout Alberta showed that high levels of compaction, observed uniformly or as a plow plan, largely inhibited faba bean productivity. Furthermore, conditions of high water availability were able to partially mask the detrimental effects of high compaction, while a relatively lower water availability representing field moist conditions displayed great disparity in faba bean productivity among varying levels of compaction. Additionally, improvements to un-trafficked soil quality and its corresponding spatial structure were quantified at the field scale through standard and hybrid geostatistical methods. Extrinsic factors from the CTF management system predominantly influenced the spatial structure of soil physical and hydraulic quality parameters, which were best predicted through regression and regression kriging methods. Moreover, intrinsic variations due to landscape features and water movement were shown to highly contribute to the spatial structure of soil nutrient quality parameters. Furthermore, topographic influence on the spatial structure of soil nutrient properties were highlighted, as terrain-derived covariates (e.g., elevation and topographic position index) paired with the covariate kriging method yielding the best model.

  • Subjects / Keywords
  • Graduation date
    Fall 2017
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.