Making do with less Senior adviser, Plant nutrition Leif Knudsen, DAAS Dansk Landbrugsrådgivning Landscentret | Planteproduktion

Making do with less: Nitrogen statistic for Denmark Trials with increasing amounts of Nitrogen Different types of nitrogen fertilzer in cereals, maize and potatoes Starter fertilizers to maize Manganese and other micronutrients Reducing leaching of nitrogen

Imported Exported Surplus Kyllingsbæk, 2005 Nitrogen account for Denmark

Mineral fertilizer Animal manure Input of nitrogen in Danish Agriculture Input reduced 35 pct from 84/85 to 04/05

Nitrogen in animal manure from cattle Milk yield, ECM per cow Excr. kg per cow Excr. gr. per kg ECM19,516,815,4 Dairy cows, 1, Kg N from cattle, 1,000 t

Nitrogen excretion from pigs Excretion of nitrogen per kg produced kg meat

Yield in winter wheat Hkg per ha Belgium Denmark France Germany Netherland Sweden UK

Results of trials with increasing amounts of nitrogen 2006Ave , ,765 Winter wheat 11057, ,754 S.Bar- ley Opti- mal N, kg/ha Yield, deci- ton/ha No. of tri. Opti- mal N, kg/ha Yield, deci- ton/ha No. of tri.

ENTEC fertilizer to spring barley, 3 tr Kg N in grain per ha Reference NS 24-7 ENTEC NS Kg N per ha

Sulfammo NS Sulfammo NS to winter wheat, 5 tr Kg N uptake in grain per ha

9,5 10,0 10,5 11,0 11,5 12,0 12, Percent protein NS NS N-plus-- 4 trials with N-Plus to winter wheat N i N-Plus st N i N-Plus st x 10 N i N-Plus

Nitro gen Phos- phor. Yield and response Units per ha

Winter barley without spraying with manganese sulphate Winter barley without spraying with manganese sulphate Winter barley with 2 x autumn spraying with 2,5 kg manganese sulphate Winter barley with 2 x autumn spraying with 2,5 kg manganese sulphate

30 N in calcium- nitrate footplaced 30 N in amm.sul- phate footplaced 2 x MnSO 4 autumn sprayed Untreated 2 trials with foot placed fertilizer to prevent manga- nese deficiency in winter barley, 2006 Picture from trial no. 001 April ,6+30,70 -1,6+21,1+ 9,923,6 Yield and yield response tr. 001 og 002

trials,4 trials2 trials3 trials Untreated 67,468,262,256,5 Copper-0,2-0,4-0,32,0 Zinck0,1-0,2-1,7-2,4 Magnesum,sulphur-0,9 0,01,6 Nutrimix (Mix)-0,6-0,4-0,7-1,3 Epso Combitop (Mix)-1,40,10,50,2 Micro Mix.-0,7-1,3-1,7-0,5 Manganese-0,40,6-1,22,0 Selenium-1,5 - - Boron -0,4 --1,4 ns Yield and yield response, dt per ha Winter wheat Spring barley Trials with micronutrients

Leaching of nitrogen, kg N/ha 60 kg N/ha 120 kg N/ha Spring barley, with and without catch crops Ploughed spring Without catch crop Ploughed spring with catch crop Effect of reduced N supply: 20 kg N reduced leaching = 30 pct. of N reduction Catch crops give more than a 50 per- cent reduction in leaching

Mustard as an intercrop between two winter wheat crops or sown together with winter wheat Mustard as an intercrop between two winter wheat crops or sown together with winter wheat

Kg N-min per 25 cm soil per ha Depth cm Winter wheat Sown at normal time N-min 98 kg N/ha Mustard as intercrop N-min 70 kg N/ha Very early sown winter wheat, N-min 63 kg N/ha Mustard + winter wheat N-min 30 kg N/ha Reduction of leaching in rotations dominated by winter cereals

Does the Danish regulation of nitrogen work and does it have an environmental impact? Clay soils, >10 pct. clay Upper ground water Root zone Mg nitrate-N per liter 90/ /2005 Sandy soils (<10 pct. clay

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