Water quality management

To reduce eutrophication of waters is an important issue for agriculture today. The long-term field leaching experiments at the department of Soil and Environment have been important for the development of cropping practices to improve nutrient use efficiency and decrease nutrient leaching from agricultural land. The field leaching facilities consist of separately tile-drained plots with continuous measurements of drainage water flow and flow-proportional water sampling from each plot. This enables studies of how different management practices and crops affect leaching of nutrients from the soil. The leaching experiments within the programme of long-term field experiments are located at four sites in southern Sweden. Both organic and conventional cropping systems are represented. Management practices include for example different soil tillage systems, applications of cattle and pig slurry, different types of cover crops and green manure crops.

Conventional cropping systems

Site: Lönnstorp, southwest Sweden (Lund)

Soil texture: loam

Start: 1993

Crops: Crop rotations with different types of cover crops. Cereals, oilseed crops, sugar beets and energy crops have been studied.

Site: Mellby, southwest Sweden (Laholm)

Soil texture: sand

Start: 1983

Crops: Spring cereals with three fertiliser regimes (control, mineral fertilizer, pig slurry), with and without undersown cover crop of perennial ryegrass

Site: Lanna, west Sweden (Skara)

Soil texture: clay

Start: 1993

Crops: Spring  cereals and oilseed crops in two different soil tillage systems, i.e. mouldboard ploughing and reduced tillage

Site: Fotegården, west Sweden (Lidköping)

Soil texture: sand

Start: 1993

Crops: Spring cereals and potatoes with and without cover crops and different times of ploughing

Organic cropping systems

Site: Mellby, southwest Sweden  (Laholm)

Soil texture: sand

Start: 1998

Crops: Organic crop rotation without application of animal manure. Annual grass/clover crops, spring wheat, winter rye and broad bean.

Site: Mellby, southwest Sweden  (Laholm)

Soil texture: sand

Start: 1991

Crops: Organic crop rotation representing a dairy farm with cattle slurry applications. Three-year grass/clover forage crop, spring barley and oats.

Site: Lanna, west Sweden  (Skara)

Soil texture: clay

Start: 1998

Crops: Organic crop rotation without application of animal manure. Annual grass/clover crops, oats, winter wheat and broad bean.

Site: Lanna, west Sweden  (Skara)

Soil texture: clay

Start: 1998

Crops: Organic crop rotation representing a dairy farm with cattle slurry applications. Two-year grass/clover forage crop, spring barley and oats.