Adaptation of seedbed preparation for spring cereals to unfavourably high soil moisture conditions in loam soil

Abstract

In the future, increased precipitation in spring may force Scandinavian farmers to prepare their cereal seedbeds under conditions with excessive soil moisture, and thereby risk soil compaction, oxygen deficiency and yield loss. To adapt to climate change and avoid yield loss, a possible strategy may be to increase moisture loss from the seedbed, in contrast to earlier seedbed research, which has focused on minimising moisture loss. In this study, we compared light and heavy mechanisation alternatives for secondary tillage in an experiment with relatively dry and excess moisture conditions. The mechanisation alternatives’ suitability for excess moisture conditions was assessed in terms of resultant aggregate size distribution, penetration resistance, bulk density, air-filled porosity, air permeability, soil moisture content and cereal emergence. In general, lighter mechanisation created more favourable seedbed characteristics and seemed to be more suitable under excess soil moisture conditions. Larger aggregates after heavier mechanisation did not result in lower soil moisture content, probably because of compaction in the seedbed. We conclude that, under Norwegian conditions, the most important adaptation to climate change in seedbed preparation for spring cereals is the avoidance of compaction. Implement management for seedbed preparation should be more differentiated.

Keywords

• compaction
• mechanisation strategy
• secondary tillage
• sowing
• workability