Centre for Development and Environment (CDE)

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Does use of the “Dyker” reduce soil erosion and waterlogging in conventionally farmed potato fields? A field trial in the Frienisberg area

Researchers of CDE are currently examining the effects of a device called “Dyker” on several potato fields in the Frienisberg area near Bern, Switzerland. The study is part of the European RECARE project. The Dyker consists of a set of wheels with three inclined shovels each. Attached to the rear end of the planting machine, it digs holes into the bottom of the furrows between the potato hills. The holes are intended to improve water infiltration and to help retain water near the plants, while preventing waterlogging and stagnant water in depressions and minimizing surface runoff and soil erosion.

Dyker, potato field
With Dyker
Furrows treated with the Dyker (lower photos) show less sighs of erosion and soil accumulation compared to untreated furrows (upper photos). Photos: Tatenda Lemann, CDE

In order to assess and measure the effectiveness of the Dyker in conventional potato farming, potatoes in several fields were planted in alternating sets of rows with and without use of the Dyker. Drone photographs and measurements show that in fields with a slope gradient of more than 5 percent, furrows treated with the Dyker clearly displayed less signs of erosion compared to untreated furrows. In addition, their accumulation zones had collected less eroded soil than those of untreated furrows..

The Dyker in use with a Grimme GL 420 potato planter. Video: Tatenda Lemann, CDE

A series of drone photographs of a field with a slight depression further shows how the Dyker affects infiltration and stagnant water. In treated furrows, rainwater was evenly retained in the holes and infiltrated the soil locally, rather than collecting in the depression. Not so in untreated furrows: Here, much of the water remained on the surface and ran off into the depression. The amount of water that collected there exceeded the soil’s infiltration capacity and stood in the furrows for several days, creating anaerobic conditions in the adjacent potato hills. This prevented the plants from growing and ultimately led to crop failure.

Dyker potato field
In rows that had not been treated with the Dyker, waterlogging prevented the growth of potato plants in a depression (see middle to right part of photo). Photo: Tatenda Lemann, CDE

These first measurements and assessments demonstrate that the Dyker helps to reduce erosion and stagnant water in conventional potato farming. By the end of the study in December 2017, these results will be combined with those of further tests and evaluations, with the aim of providing a general assessment of the Dyker’s effectiveness in improving soil functions and ecosystem services, as well as the costs and benefits associated with its use.