Transcript No Slide Title

Benefits and risks of applying compost to
European soils
Luca Montanarella
Status of Soil Organic
Carbon in European soils:
Spatial data layer of
estimated OC contents in the
surface horizon of soils in
Europe (30cm), 1km grid
size.
Soil Organic Carbon dynamics
Terrestrial organic carbon pool
Max. potential carbon stock at climax
Max. potential carbon stock achievable through LULUCF measures
Actual terrestrial carbon stock
Terrestrial carbon stock
depletion by historical human
induced LULUCF activities
Hypothetical carbon
stock build-up by
LULUCF measures
time
Ca. 60,000 B.C. to 1000-1500 A.D Last “green” revolution
present
future
Monitoring SOM on Broadbalk, Rothamsted
%OC
3
2.5
Management/vegetation
Old pasture (8-18cm)
Old woodland (13-18cm)
Broadbalk,
after
50
years
continuous wheat, 1893
No manure since 1839 (0-23cm)
Complete minerals and 185kg
(NH 4)2SO4 most years since 1843
14 tons of farmyard manure
annually since 1843 (0-23cm)
%C
1.5
2.4
0.9
1.1
FYM
2.2
FYM since 1885
2
1.5
FYM since
1968
NPK
1
No fertilisers or manures
0.5
FYM applied at 35 t ha-1 yr-1
19
90
19
70
19
50
19
30
19
10
18
90
18
70
18
50
0
Goulding
Soil specific carbon sequestration potential
Max & Min tC are
soil specific
tC
100
Max tC 90
80
70
60
Actual tC50
40
30
20
10
0
Min tC
0
5
Carbon Sequestration
Rate, CSR
Potential Carbon
Sequestration,
PCS
Carbon Loss Rate, CLR
Potential Carbon
loss, PCL (Risk
assessment)
10
15
20
Years
SOC content is depending on humidity,
temperature, soil type and land use
Example:
Change in organic carbon content
of topsoils in England and Wales
[after Loveland, NSRI, Cranfield University, Silsoe]
Carbon losses from all soils across England and Wales 1978-2003
(Bellamy et al., Nature Sep 2005, based on ca. 6000 samples, 0-15cm)
Bellamy et al. estimate annual losses of 13 million tonnes
of carbon. This is equivalent to 8% of the UK emissions
of carbon dioxide in 1990, and is as much as the entire
UK reduction in CO2 emissions achieved between 1990
and 2002 (12.7 million tonnes of carbon per year).
Total biowaste and green waste arising in the European Union (1,000 t/y)
•Country
•Austria
•Municipal
solid waste
production
•4 110
•Biowaste
actually
collected
•Greenwaste
actually
collected
•880
•850
•Biowaste
potentially
collectable
•Greenwaste
potentially
collectable
•1 220
•1 020
•(*) 580
•BelgiumFlanders
•(***) 4 781
•BelgiumWallonia
•900
•120
•160
•12 000
•14 000
•48 715
•Denmark
•2 787
•280
•490
•50
•550
•France
•21 100
•74.7
•860.6
•9 006
•5 900
•Finland
•2 100
•100
•600
•Spain
•14 296
•(**) 60
•/
•6 600
•Greece
•4 200
•/
•/
•1 800
•27 000
•(****) 1 100
•/
•9 000
•1 848
•/
•/
•440
•Ireland
•Luxembourg
Modified for France by I. Feix. Data from
Germany are from the report
Bundesgütegemeinschaft Kompost: Verzeichnis
der Kompostierungs- und Vergärungsanlagen in
Deutschland, 2003.
•390
•Germany
•Italy
J. Barth, An estimation of European compost
production, sources, quantities and use, EU
Compost Workshop “Steps towards a European
Compost Directive”, Vienna, 2-3 November 1999.
•330
•299
•30
•60
•Netherlands
•8 480
•1 500
•800
•Portugal
•3 600
•/
•10
•Sweden
•3 998
•130
•150
•United
Kingdom
•28 989
•39
•860
•European
Union
•176 303
•15 854.3
•2 500
•1 000
•1 300
•970
•530
•3 200
•54 806
•(*) Biowaste of industrial origin; (**) Catalonia; (***) Belgium total; (****) Italy: CIC and Italian Environmental Agency data for 2002.
Soil organic matter
Origin
Turnover
Complexity
Corg
CO2
Decomposing fresh OM
(Particulate organic matter)
soluble OM
-OH
Colloidal OM
Polysaccharides and biomolecules
Humic substances
Microorganisms
Model of soil carbon
dynamics
Vegetation, organic input
Primary production,
quality
CELL
Soil, Land
Use,
Climate
(structural
polysaccharides)
0.3 yr
LIGNIN
LABILE
2.5 yr
0,87 yr
microbial
synthesis
mineralization
CO2
HUM
(humic
and protected)
CO2
25 yr
numerical values for
soil/land use =
- 20% clay
- temperature 12°C
- water/porevolume >
0,4
- annual crops conv.
tillage
STABLE
3300 yr
CO2
Balesdent, 2000
Potential measures for cropland
0
1
2
Zero-tillage
Reduced-tillage
Set-aside
Grasses and permanent crops
Deep-rooting crops
Animal manure
Crop residues
Sewage sludge
Composting
Improved rotations
Fertilisation
Irrigation
Bioenergy crops
Extensification
Organic farming
Freibauer et al. 2003
3
4
5
6
7
t C/ha/y
Measure
Potential soil C
sequestration
rate
(t CO2.ha-1.y-1)
Estimated
uncertainty
(%)
Ref. /
notes
Limiting factor
Soil
sequestration
potential (106
CO2.y-1) given
limitation
Ref. /
notes
Animal
manure
1.38
> 50%
1
Manure available = 385.106
t dm.y-1
86.83
4
Crop residues
2.54
> 50%
1
Surplus straw = 5.3.106 t
dm.y-1
90.46
5
Sewage sludge
0.95
> 50%
1, 2
Sewage sludge available in
the mid-time (2005) =
8.3.106 t dm.y-1
6.30
6
Composting
1.38 or higher
>> 50%
3, 2
Potential production of
composted
materials
present in MSW = 13 to
22.106 t dm.y-1. Figures
include
processing
of
biowaste
from
agroindustrial by-products, but
neither manure, nor crop
residues.
11
7
-1. Smith et al. (2000); per hectare values calculated using the average C content of arable top soils (to 30 cm) of 53 t C.ha-1; Vleeshouwers and Verhageb (2002), cf. table 5.
-2. The sequestration values are based on a load rate of 1 t ha-1.y-1, which was the lowest safe limit in place (in Sweden) at the time of analysis for this figure (1997). A higher loading rate would give a higher sequestration rate per
area. As the limiting factor for the application of compost is the amount of producible compost, a higher loading rate on a certain area would imply that a more limited area could be treated.
-3. Assumed to be the same as animal manure figure of Smith et al. (2000).
-4. Total figure for EU15 calculated from figures in Smith et al. (2000). Total amount of manure available from Smith et al. (1997).
-5. Total figure for EU15 calculated from figures in Smith et al. (2000). Total amount of surplus cereal straw available from Smith et al. (1997).
European Climate Change Programme ECCP 2000-2001
Total carbon sequestration potential of measures for increasing soil carbon stocks
in agricultural soils for Europe (EU15) and limiting factors.
Comparative rates and loads of Cu inputs into French soils
Land surface
(%UAA)
Mean level of Cu
(mg.kg-1 dm)
Cu rates
(kg.ha-1.y-1)
Cu annual loads
(t.y-1) over
France
1 to 4%
334
0.668
165
MSW compost
0.1%
164.4
0.822
47
Greenwaste compost
0.2%
50.8
0.254
14
Households
compost
0.02%
87.8
0.439
1
Animal effluents
20-25%
Ex.: 52 cattle; 730
pigs
0.7 cattle;
2.3 pigs
4 460 (all an.
effl.)
P fertilisers
80-90%
/
0.004
102
~3% (vineyards &
arboriculture)
/
0.8 to 14
752 to 13 152
100%
/
0.006 to
0.015
185 to 462
Urban sewage sludge
Biodegradable
wastes
Agricultural
practices
Cu fungicides
Atmospheric
depositions
TWG Organic Matter
biowaste
Fig. I.1: Heavy Metal Contents in European Soils
according to Soil Parent Material and Land Use
- Cadmium -
Fig. I.3: Heavy Metal Contents in European Soils
according to Soil Parent Material and Land Use
- Copper -
Map Sources:
European Soil Data Base, Version 1.0
CORINE Land Cover, Version 12/2000
Status June 2003
Classes of Cu Content
[mg/kg]
- Median values -
Map Sources:
European Soil Data Base, Version 1.0
CORINE Land Cover, Version 12/2000
Status June 2003
Classes of Cd Content
[mg/kg]
- Median values -
Conclusions
• Soil Organic carbon levels in Europe are low and are constantly
declining.
• There is the urgent need to reverse this negative trend
• Compost and bio-waste could provide a valuable source of
organic matter for European soils.
• Long-term fate of the exogenous organic material in soils needs
to be taken into account, depending on the pedo-climatic local
conditions.
• Potential contamination of bulk organic materials, like compost,
sludges and other bio-wastes is a potential threat to human
health
• Careful application of QA/QC and of the precautionary principle
is a pre-requisite for increased acceptance of these materials as
soil improvers.