PHOSPHORUS USE AND RECYCLING
IN ORGANIC FARMING IN DENMARK
Margrethe Askegaard, M.Sc. Agric., PhD
[email protected], SEGES Organic farming
“Phosphorus a Limited Resource - Closing the Loop”, Malmø 28th October, 2016
SWOT ANALYSIS FOR THE USE OF URBAN
ORGANIC WASTES IN ORGANIC FARMING
2..
Strengths:
• Use of urban organic wastes
corresponds with the Danish
Resources Strategy for waste
management
• Promotes the EU target for increased
use of wastes and recirculation in
organic farming
Weaknesses:
• Challenges the organic
precautionary principle because
urban organic waste may include
toxic components.
Opportunities:
• Promotes conversion to organic
farming, especially in Eastdenmark
• Higher yields
• Elevated Danish production of feed
concentrates.
• Reduced carbon footprint
Threats:
• Negative consumer reactions to
meat and bone meal, or sewage
sludge or related residual products
• Detection of new problematic
elements in accepted waste
products
DO WE HAVE A PROBLEM WITH PHOSPHORUS
DEFICIENCY IN ORGANIC FARMING?
● We don’t know!
● Organic farmers focuses on N, K and S as yield limitingfactors – not P.
● The willingness to pay for P is relatively low.
● But we need to be much more aware of the P-supply to the soils, especially in the eastern part of Denmark.
● And organic agriculture need to get access to the availableP sources now – before they all flow in to streams addingforbidden substances.
3..
THE MAIN CHALLENGE:
4..
NS
KP
THE GEOGRAFIC DISTRIBUTION OF P-SURPLUS IN
DENMARK
5..
Vi har opsparet 1,4 ton P/ha,
men de er uens fordelt, og
så er jo også udfasningen
der ”truer”
2005 2013
Andersen et al. 2016. Redegørelse for udvikling i landbrugets fosforforbrug, tab og påvirkning af
vandmiljøet. Teknisk rapport fra DCE – Nationalt Center for Miljø og Energi
DIFFERENT P-STATUS IN EAST AND WEST
DENMARK
6..Olsen-P (Pt) intervals
0,0
- 0,9
1,0
- 1,9
2,0
- 2,9
3,0
- 3,9
4,0
- 4,9
5,0
- 5,9
6,0
- 6,9
7,0
- 7,9
8,0
- 8,9
9,0
- 10,
0
> 10
,0
Dis
trib
ution o
f soil
test analy
sis
(%
)
0
10
20
30
40
Sealand
Western Jutland
FARMGATE P-BALANCES 2007-2008
7..
Organic dairy farms
Livestock units ha-1
0,6 0,8 1,0 1,2 1,4 1,6 1,8
Surp
lus (
kg P
ha
-1)
-10
-5
0
5
10
15
20
25
30
NITROGEN AND PHOSPHORUS APPLICATION IN
ORGANIC FIELDS
8..
Extract from fertilizer accounts
2013/2014 for organic farms.
Include both own and
purchased organic fertilizers.
kg h
a-1
0
10
20
30
40
50
60
70
80
90
100
110
120
130
Total-N
NH4-N
P estimated
Sealand
Funen
Bornh
olm
Jutla
nd E
ast
Jutla
nd N
orth
Jutla
nd W
est
POTENTIAL PHOSPHORUS RESSOURCES
9..Ton P per yr.
0 1000 2000 3000 4000
Vinasse
Biomass cuts from streams
Roadside cuts
Food waste from retail and production
Protamylasse
Fertigro
Wood ash
Biomasses from natural areas
Green garden and park waste
Source separated food waste private households
Novogro
Meat and bone meal
Sewage sludge
Not permitted
Permitted
Permitted ( )
10..
Thank you for your attention