Frans Aarts

1
Frans Aarts
Plantekongres 2005, Denmark
Nutrient balances experiences from The
Netherlands

• Wageningen University and Research Centre (W-UR)
• Plant Research International

2
Agricultural facts

• Denmark
• agricultural land 2.7 million ha
• animal production 5 billion euro

• Netherlands
• agricultural land 1.9 million ha
• animal production 8 billion euro
• 24,000 dairy farms (grass, maize)
• 6,000 pigs/chicken farms (no land)

3
Agricultural facts

• Denmark
• agricultural land 2.7 million ha
• animal production 5 billion euro

• Netherlands
• agricultural land 1.9 million ha
• animal production 8 billion euro
• 24,000 dairy farms (grass, maize)
• 6,000 pigs/chicken farms (no land)

high
very high
Livestock density
4
Manure-N (1997)

• Netherlands
• 258 kg N/ha on average
• 288 kg N/ha on dairy farms
• Denmark
• - 90 kg N/ha on average

5
Effect of livestock density on N balance (Denmark)
6
Effect of livestock density on N balance (EU, le
Gall)
7500 kg milk 170 kg N-manure
7
Effect of livestock density on N balance (le Gall)
Dutch average
8
Effect of livestock density on N balance
N surplus/ha ( input output)
manure-N/ha
9
Nitrates directive
N surplus
190 kg
manure-N/ha
170 kg EU nitrates directive
10
Nitrates directive
N surplus
355 kg
190 kg
manure-N/ha
170 kg EU nitrates directive
288 kg
Dutch dairy farms
11
Effect of livestock density on N surplus
Individual farms
N surplus
manure-N/ha
12
Effect of livestock density on N surplus
Individual farms
N surplus
On farm level livestock density is a weak
indicator for N surplus
manure-N/ha
13
N-surplus as indicator for environmental effects
Quality water
excellent
bad
N surplus/ha
14
N-surplus as indicator for environmental effects
Quality water
excellent
peat, grassland
average
dry sand, arable
bad
N surplus/ha
15
N-surplus as indicator for environmental effects
Quality water
desired
peat, grassland
average
light sand, arable
N surplus/ha
acceptable
16
N-surplus as indicator for environmental effects
Quality water
At farm level N-surplus can be a good indicator
for environmental performance
desired
peat, grassland
average
light sand, arable
N surplus/ha
acceptable
17
Surplus N related to nitrate leaching (light
sandy soils)
18
Surplus N (1998, kg/ha)
Acceptable
250 ? peat
130 light sand
19
Surplus N (1998, kg/ha)
Acceptable
250 ? peat
130 light sand
Strong reduction of surpluses is needed
20
How to reduce surpluses?

• limit to livestock density animal accounting
• or
• Limit to surpluses mineral accounting

21
Limit to livestock density
N surplus
Reducing livestock density
190 kg
288 kg
manure-N/ha
170 kg
22
Limit to livestock density
N surplus
190 kg
manure-N/ha
170 kg
23
Limit to livestock density
N surplus
190 kg
Not all farms below acceptable level
manure-N/ha
170 kg
24
Limit to the surplus of N
N surplus
Improving management
190 kg
288 kg
manure-N/ha
170 kg
25
Limit to the surplus of N
N surplus
190 kg
288 kg
manure-N/ha
170 kg
26
Limit to the surplus of N
N surplus
190 kg
All farms below acceptable level
288 kg
manure-N/ha
170 kg
27
Mineral accounting, with limited surpluses

• Advantages
• environmental quality is better guaranteed
• more attractive if land is expensive and animal
  density is high
• Disadvantages
• High cost to control
• Acceptance of EU?

28
How to reduce surpluses?

• Improve N-turnover in farm components
• less inputs needed

feed
18
Milk/meat
herd
71
crop
manure
80
53
soil
fertilizer
29
1987
200?
De MarkeAn experimental farm on light sandy
soil, with an average intensity of milk
production and very tight environmental standards
30
How to reduce surpluses?

• Improved N-turnover De Marke

feed
18
23
Milk/meat
herd
71
93
crop
manure
80
92
70
soil
fertilizer
53
31
Results 1993-1998

• Mineral fertiliser-N 70 kg/ha
• reduction of 70
• Purchased feed 2,000 kg dm/ha
• Reduction of 60
• Surplus N 150 kg/ha

32
Results 2004

• Mineral fertiliser-N 0 kg/ha
• reduction of 100
• Purchased feed 2,000 kg dm/ha
• Reduction of 60
• Surplus N 100 kg/ha

33
How to convince farmers?

• Father G. van den Elsen (founder of Rabo-bank,
  Campina etc.) It is
  impossible to convince farmers only with books
  and journals. The truth should be pumped into
  their heads by clear, visible examples.
  (Sociologie der Boeren,
  1918)
  
  

34
1999
2005
Cows Opportunitiescommercial intensive dairy
farms, demonstrating possibilities to realise low
surpluses
35
Characteristics of pilot farms
36
Environmental performance pilot farms
37
Economics
Income
N surplus
Measures to reduce surplus
38
Economics
Income
N surplus
Pilot farms
measures
39
Economics
Income
N surplus
2,500 euro
Pilot farms
measures
40
Dutch Mineral Accounting System (1998 2006)
Farm gate balance
Input
Output
concentrates
livestock
milk, livestock
roughage
roughage
manure
manure
artificial fertilizer
Farm gate surplus
41
Dutch Mineral Accounting System (1998 2006)
Farm gate balance
Input
Output
concentrates
livestock
milk, livestock
roughage
roughage
manure
manure
artificial fertilizer
About 70 kg N below real surplus (including
deposition, clover etc.)
Farm gate surplus
42
Permitted farm gate surpluses (kg N/ha)
On light sandy soils 40 kg less
43
Real N-surplus of very specialized dairy farms
(kg/ha)
(-150)
Average annual decrease 38 kg 11
44
Farmgate N-surplus of all dairy farms
Save area
MINAS
45
P2O5 -surplus of very specialized dairy farms
(kg/ha)
(-31)
Average annual decrease 8 kg 13
46
The future

• ? We love mineral accounting, but European Court
  of Justice does not ?

47
The future

• ? We love mineral accounting, but European Court
  of Justice does not ?
• We will introduce application standards for
  fertilizers in 2006 ?

48
The future

• ? We love mineral accounting, but European Court
  of Justice does not ?
• We will introduce application standards for
  fertilizers in 2006 ?
• We expect that costs will increase for farmers ?,
  but costs for government will be lower ?

49
The future

• ? We love mineral accounting, but European Court
  of Justice does not ?
• We will introduce application standards for
  fertilizers in 2006 ?
• We expect that costs will increase for farmers ?,
  but costs for government will be lower ?
• We hope that in the future a mineral accounting
  system can be reintroduced, because nutrient
  surplus is the better indicator for environmental
  quality ?

50

• Thanks!