Poor soil management damaging enviroment
Farming Systems for the New Millennium was the title of a
recent Association of Applied Biologists conference in
Cambridge. Edward Long relays some of the highlights
INAPPROPRIATE soil management due to sodden conditions this autumn and winter has created environmental problems. But less damage has been done where land has not been ploughed, according Vic Jordan chief executive of Soil Management Initiative.
Dr Jordan believes valuable lessons have been learned. "Damage done to the environment by the wrong soil management policy is worse this year than ever before.
"The main problems include soil erosion due to water run-off and loss of nutrients causing pollution. There was only a brief period last autumn when it was possible to work the land properly."
The result has been poor water infiltration into soil. On some flooded land water has sunk to a depth of only a few inches before hitting a compacted layer, moving horizontally and leaving dry soil beneath a pan.
"Where min-till has been used, percolation is possible so water can get away better. In plots where land was ploughed the soil is puddled and waterlogged, but in min-till plots water has been absorbed and field drains are running freely.
"Immediate post-harvest incorporation of stubble and soil consolidation provided a sufficiently firm seed-bed to drill without having to totally invert the soil. This has agronomic and environmental benefits that will build over time."
Useful soil management lessons have been learned during recent wet weather, says Vic Jordan. Minimum tillage has proves valuable (see below).
• 43% increase in infiltration.
• 48% reduction in run-off.
• 68% less sediment lost.
• 81% less phosphate removed.
• 69% cut in soil mineral N depletion.