Tuesday, November 6, 2007
210-3

Tillage Translocation and Tillage Erosion within Intensive Potato Production Systems in Atlantic Canada.

Kevin Tiessen, Macdonald Col.-McGill Univ., Dept of NRS, McGill University, 21 111 Lakeshore Road, Ste. Anne de Bellevue, QC H9X 3V9, CANADA, Guy Mehuys, CANADA,McGill U., Dep. of Natural Resource Sci., Macdonald Campus Mcgill University, Ste Anne De Bellevue, QC H9X 3V9, CANADA, David Lobb, University of Manitoba, Department of Soil Science, University of Manitoba, Winnipeg, MB R3T 2N2, Canada, and Herb Rees, Agriculture and Agri-Food Canada, Potato Research Centre, 850 Lincoln Road, P.O. Box 20280, Fredericton, NB E3B 4Z7, Canada.

In Canada, there is growing acceptance that tillage erosion is a serious form of soil degradation and a threat to the sustainability of agriculture across the country. To date, the potential risk for tillage erosion within potato production systems has not been investigated. The objective of this project was to generate tillage translocation and erosivity values for implements common to conventionally and conservation tilled potato production systems in Atlantic Canada.

Both systems require numerous tillage operations: primary fall tillage [mouldboard (MP) vs. chisel plough (CP)], secondary spring tillage [offset disc (OD) vs. vibrashank (VS)], and “tertiary” tillage operations [implements involved in planting, cultivating and hilling (PCH) and harvesting (HARV) operations]. Our results show that each primary, secondary and tertiary tillage operation is potentially erosive, as each moved large quantities of soil over considerable distances. After one pass, all six tillage operations tested moved soil at least 3 m, with the furthest translocated distances observed for the PCH sequence (23.6 m) and for the CP, VS and HARV (approx. 6 m). The mass of translocated soil was largest for the PCH sequence (115.9 kg m-1), followed by the HARV (71.7 kg m-1), CP (64.4 kg m-1), MP (43.3 kg m-1), OD (35.0 kg m-1) and VS (34.9 kg m-1). Overall, the potential for tillage erosion was greatest for the PCH sequence and HARV (3.6 and 3.0 kg m-1 %-1 pass-1, respectively), followed by the MP, CP and OD (1.8 to 1.9 kg m-1 %-1 pass-1), and finally the VS (0.3 kg m-1 %-1 pass-1). It is apparent that conservation, secondary and tertiary tillage implements can move as much soil as conventional tillage implements, such as the mouldboard plough, and must be considered when developing best management practices to improve soil conservation strategies for potato production systems in Canada and worldwide.