Making do with less

Senior adviser, Plant nutrition

Leif Knudsen, DAAS

Dansk LandbrugsrådgivningLandscentret | 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

0100200300400500600700800

1000

tons

of N

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

1985 1996 2004

Milk yield, ECM per cow 6300 7600 8745

Excr. kg per cow 123 128 134

Excr. gr. per kg ECM 19,5 16,8 15,4

Dairy cows, 1,000 890 701 569

Kg N from cattle, 1,000 t 170 142 115

Nitrogen excretion from pigs

Excretion of nitrogen per kg produced kg meat

Yield in winter wheat 1980-2006

30

40

50

60

70

80

90

100

1980 1985 1990 1995 2000 2005 2010

Hkg

per

ha

Belgium

Denmark

France

Germany

Netherland

Sweden

UK

Results of trials with increasing amounts of nitrogen

2006Ave. 2001-2005

16984,51619684,765Winterwheat

11057,91713058,754S.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. 2006

0

20

40

60

80

100

120

0 50 100 150 200 250

Kg

N in

gra

in p

er h

a

Reference NS 24-7

ENTEC NS 26-13

Kg N per ha

Sulfammo NS 23-18

0

20

40

60

80

100

120

140

160

180

0 50 100 150 200 250 300

Sulfammo NS 23-18 to winter wheat, 5 tr. 2006K

g N

upt

ake

in g

rain

per

ha

9,5

10,0

10,5

11,0

11,5

12,0

12,5

150 175 200 175 175 175

Per

cent

pro

tein

-------NS 24-7------- --NS 24-7 + N-plus--

4 trials with N-Plus to winter wheat 2006

20 N

i N

-Plu

s st

. 51

20 N

i N

-Plu

s st

. 37

2 x

10 N

i N

-Plu

s

Table 12. Starter fertilizer to maize for silage

N P

Trial no. 1 21. No fertilizer - - 113,5 79,02. 81 kg NS 24-7 19 - 5,6 13,83. 116 kg NP 17-9-0 m. S 19 11 4,4 18,24. 128 kg NP 16-8 20 10 8,6 9,75. 123 kg NP 16-5 m. Humifirst 20 6 9,8 22,86. 95 kg NP 16-5 m. Humifirst 15 5 0,1 17,97. 78 kg ENTEC (NP 25-7) 20 5 8,3 19,18. 160 kg ENTEC (NP 25-7) 40 11 13,9 24,89. 240 kg NP 17-9-0 m. S 40 22 17,2 32,9LSD ns ns

Maize, silage

kg per ha

Nitrogen

Phos-phor.

Yield and responseUnits 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 MnSO4

autumn

sprayedUntreated

2 trials with foot placed fertilizer to prevent manga-nese deficiency in winter barley, 2006

Picture from trial no. 001 April 2006Picture from trial no. 001 April 2006

0+51,6+30,70

-1,6+21,1+ 9,923,6

Yield and yield response tr. 001 og 002

2005 2006 2005 20066 trials, 4 trials 2 trials 3 trials

Untreated 67,4 68,2 62,2 56,5Copper -0,2 -0,4 -0,3 2,0Zinck 0,1 -0,2 -1,7 -2,4Magnesum,sulphur -0,9 -0,9 0,0 1,6Nutrimix (Mix) -0,6 -0,4 -0,7 -1,3Epso Combitop (Mix) -1,4 0,1 0,5 0,2Micro Mix. -0,7 -1,3 -1,7 -0,5Manganese -0,4 0,6 -1,2 2,0Selenium -1,5 - -1,5 -Boron - 0,4 - -1,4

ns ns ns ns

Yield and yield response, dt per ha

Winter wheat Spring barley

Trials with micronutrients 2005-2006

0

10

20

30

40

50

60

70

80

Le

ach

ing

of n

itro

ge

n, k

g N

/ha

60 kg N/ha120 kg N/ha

Spring barley, with and without catch crops

Ploughed springWithout catch crop

Ploughed spring with catch crop

Effect of reduced N supply: 20 kg N reducedleaching = 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 togetherwith winter wheat

Mustard as an intercrop between two winter wheat crops or sown togetherwith winter wheat

0 5 10 15 20 25 30 35 40

0-25

25-50

50-75

75-100

Kg N-min per 25 cm soil per ha

Dep

th c

m

Winter wheatSown at normal timeN-min 98 kg N/ha

Mustard as intercropN-min 70 kg N/ha

Very early sown winter wheat, N-min 63 kg N/ha

Mustard + winter wheatN-min 30 kgN/ha

Reduction of leaching in rotations dominated by winter cereals

Does the Danish regulation of nitrogen work anddoes it have an environmental impact?

Clay soils, >10 pct. clay

Upper ground water

Upper ground water

Root zone

Root zone

Mg

nitr

ate-

N p

er li

ter

90/91 2004/2005

Sandy soils (<10 pct. clay

Thank you for your attention