View
218
Download
0
Category
Preview:
Citation preview
Soutenance pour l'habilitation à diriger les recherchesUniversité Pierre et Marie Curie, UFR des Sciences de la Terre
Benoît GABRIELLEChargé de Recherche
UMR INRA INA P-G
Environnement et Grandes
Cultures
20 Janvier 2006
L'évaluation environnementale des
agrosystèmes:
une approche intégrée pour gérer les
risques agri-environnementaux
2
Context - 1
A growing demand for agricultural produce...
Tilman et al., Agricultural sustainability and intensive production practices, Nature 418: 671-677, 2002
2050
4.0
(109 t
onne
s)
2010
Bio-fuels in EuropeDirective 2003/30 EC
3
Context - 2
...currently met with increased reliance on exogenous inputs...
b: total global use of N and P fertilisers, and area of irrigated land
c: global pesticide production and imports
(Tilman et al., 2002)
4
Context - 3
...albeit with decreasing marginal efficiency
“Pest control methods with a potential efficiency of 100% raise an issue of durability for agricultural practices [...] similarly to the problem of antibiotics becoming less effective in medicine.” (INRA-Cemagref, Joint expertise report on Pesticides, Agriculture and the Environment, 2005)
(Tilman et al., 2002)
5
Context - 4
Agriculture is being pointed out as a major source of
negative environmental impacts
IFEN,6th report on water quality inFrance (2004)
6
Context - 5
Potential impacts from agriculture
CO2
Groundwater
NO3
Fertilizers (N)Pesticides
SolSoil organicmatter
N2O, NO,NH3,Pesticides
Eutrophication
Global warming
Air pollution
Ecotoxicity
Pesticides
Acidification
7
An unresolvable quandary ?
Humans have made unprecedented change to ecosystems in
recent decades to meet growing demands for food, fresh water,
fibre and energy.
Various techniques being used increasingly in various parts of
the world allow [...] productive use of land while keeping
favorable conditions for nature.
The approach taken by the Millenium Ecosystem assessment
could provide a useful tool to enable decision-makers to
understand far better the full consequences of their action.
MILLENIUM ECOSYSTEM ASSESSMENT – UNLiving beyond our means: natural assets and human well-being – Statement of the Board
8
Methodology for environmental assessment
Need for integrated assessment, across
Compounds and environmental compartments
Elementary parts of a production chain
Time
A spatial territory relevant to the production or
environmental issue at stake
To avoid or manage trade-offs between
Environmental issues
Geographical locations
Generations !
9
Managing a production chain versus a territory
?
10
The 'functional' side: life cycle assessment (LCA)
LCA, a conceptual framework to address environmental impactsfrom the 'cradle to the grave'
Renewable carbonFertilizersPesticides
Inputs:
Outputs:CO2, CH4, NOx
Fossile carbonOther fossile resources
Products et co-products
NO3-, N20... Pesticides
In agriculture, LCA was applied to waste management, cropping systems analysis, and bio-energy chains.
11
Estimation of fluxes
Outputs
Inputs
Emissions
InputX
Indirect emissions
E = a X +/-
Industry
Direct emissionsE within several
orders of magnitude!
InputX
Agriculture
PerturbationsE = f(soil, climate , managt, X)
12
Capturing the spatial variability of field emissions
Gabrielle, Laville, et al. (submitted to Global Biogeochem. Cycles)
Simulation ofN
2O fluxes in the
Beauce region(fluxes in kg N
2O-N/ha/yr)
13
Environmental balance models – example of CERES
Atmosphere
Soil
mineral N organic N
SOIL TRANSFERS Heat (Fourier) Water (Tipping bucket) Nitrate (Convective)
absorption
C-N BIOTRANSFORMATIONS Mineralisation - Immobilisation
Nitrification - Denitrificationdrainage,nitrate
leaching
PLANT PROCESSES Phenology Ressource capture PartitioningSenescence
crop residues
Groundwater
CO2, N
2O,
NH3, NO
14
Challenges wihtin the modelling loop
Experiments
Integration into model; calibration
detailed
lighterProcess analysis
Extrapolation
Model application
Moduleselection
15
Challenges wihtin the modelling loop
Experiments
Integration into model; calibration
detailed
lighterProcess analysis
Extrapolation
Model application
Moduleselection
16
Integration of nitrous oxide emissions
Simulation by CERES with two different N2O emission modules
Gabrielle, Laville, et al., Nutr. Cycling Agroecosys. (in the press)
Haplic calcisol
Redoxic luvisol
Haplic luvisol
--- Simulated o Observed
17
Challenges wihtin the modelling loop
Experiments
Integration into model; calibration
detailed
lighterProcess analysis
Extrapolation
Model application
Moduleselection
18
The 'eco-balance' experiment
19
Challenges wihtin the modelling loop
Experiments
Integration into model; calibration
detailed
lighterProcess analysis
Extrapolation
Model application
Moduleselection
20
Extrapolation to new sets of soils and climates
21
Challenges wihtin the modelling loop
Experiments
Integration into model; calibration
detailed
lighterProcess analysis
Extrapolation
Model application
Moduleselection
22
Model application: scenario analysis
Oilseed rape / wheat / barley crop rotation, on a rendzina soil (Indre)Data averaged over 30 years
ManagementScenario
Reduced inputs
“Sound” (Raisonné)
Business as usual
Fertiliser N dose
(kg N/ha)
Mean grainyield
(tonnes / ha)
Emissions in g N per tonne of wheat grain produced
Nitrate N2O NH
3
150
210
120
8.7
7.8
8.3
10.5
7.5
8.5 2.9
2.9
3.7
18.0
24.1
15.3
23
Is there really room for improvement ?
Technological “fixes” at the field-scale
Optimising fertiliser N applications (including variable-rate within
agricultural field)
Selection of crop rotations (eg, legume crops)
Introduction of new genotypes (eg, herbicide-tolerant)
Displacement of fossile resources (bio-energy, 'green chemistry')
Agricultural recycling of urban waste
24
Benefits of herbicide-tolerant crops ?
Calculated impacts on various environmental or population targets for rotations with or without herbicide-tolerant, genetically modified crops in Dijon.(Mamy, 2004)
25
Recycling of urban waste
Simulation of soil C variations inplots amended withurban waste composts(Gabrielle, Da Silveira, Houot, Michelin,Agric. Ecosys. Environ., 2005)
MSW: municipal solid wasteBIO: biodegradable wasteGWS: green waste + sludgeFYM: farmyard manure+N: complemented with fertilizer N
Integration into life cycle assessment of waste management Landfilling Incineration Composting Of which
field emissions
-5
0
5
10
15
20
25
Global warming (x100 kg eq. CO2)Acidification (g eq. H+)Eutrophication (g eq. phosphate)
26
Potential benefits on soil quality
Compost application may improve the structural
stability of soils (Annabi, 2004), and mitigate runoff
and erosion risks in loamy soils.
How to incorporate such qualitative impacts in life-
cycle assessment?
Pic
ture
s by
Y. L
e B
isso
nnai
s
27
Room for improvement? Maybe make room bigger....
Technological “fixes” at the field-scale
Cropping systems approach
Identification of 'best management practices' tailored to local
conditions
At the farm or production basin level
Optimal allocation of land use and agricultural inputs
Optimisation of nutrients and carbon flows (especially in livestock
systems)
Rural engineering
28
Territorial approach opens up new horizons
The introduction of new productions entails changes in
Physical and biogeochemical fluxes in local environment
Cropping systems management
Economic revenues and farm management
Organisation of labour, logistics, ...
Perception of agricultural activities by local stakeholders
29
Future research and problematics
Integration of environmental assessment with other
disciplines (agronomy, economics, social sciences)
To internalize determinants of agrosystems management
(including land use)
Also, internalize environmental impacts in the selection of
management strategies
Modelling (and experimenting)
To generate spatial distributions of input parameters, and validate
regional estimates
Long-term trends from repeated applications
Gaseous emissions (and depositions)
Encompassing ecological issues that can hardly be
tackled by flux-based methods (eg, soil quality)
30
Linking of bio-physical and economic models
Soil types
'Typical' farm
Environmental balance model
Micro-economicmodel
Agronomic scenarios(crop rotations,fertilization,decision rules, ...) N losses,
crop yields
Optimal management
Input costs,market prices, taxation, incentives, etc...
Profits,social costs
Environmentalperformance atterritorial level
31
Example: efficiency of agri-environmental measures
Profit associated with the optimal combination of nitrogen inputs reduction and soil vegetation cover under nitrate leaching constraint for a typical arable farm of Champagne-Ardennes. (Hardelin, J., Master's dissertation, 2005)
50
100
150
200
250
25,5
85 24 22 20 18 16 14 12
Nitrate leaching level (kg N per ha)
Fa
rm p
rofi
t (€
pe
r h
a)
PRAITERRE project, coordinated by G. Lemaire (INRA Lusignan), and funded for 2006-2008.
32
Large-scale simulations of N gas emissions:
Nitro-Europe
Integrated Project coordinated by M. Sutton (CEH Edinburgh), and funded under the 6th EU FP for 2006-2010.
WP 4NEU Landscape
Analysis
WP 3 NEU Plot Scale
Modelling
WP 2 NEU Ecosystem
Manipulation
WP 1 NEU
Flux NetworkWP 5
NEU EuropeanIntegration
WP 6 NEU Verification
& Reliability
CarboEurope IP plus other EU & national activities
33
Bio-energy, a model frame-work for assessment ?
Regional case-studies and chain implementation may be provided by
the R&D Cluster on Agro-Resources (in Picardie-Champagne-
Ardennes)
With support from national and European programmes (BioEnergy
Network of excellence)
Life cycle assessment may be
implemented at supply basin level,
Thereby integrating land-use change
and territorial impacts
(tentative Ph.D. Programme with INRA Laon/Reims/Mons),
With links to other sustainability indicators: economic, social,
ecological (UT Troyes)
34
Conclusion: challenges ahead
From a scientific perspective
Develop bio-physical models for environmental
assessment
Broaden the scope of the assessment and tackle
territorial impacts
...and from a personal perspective
Foster collaboration with thematically- or
geographically-distant groups
Entrust work to students (graduates or post'docs) and
colleagues
35
Merci à tous !
36
Lecture Outline
Context and issues
Méthodologie de l 'évaluation intégrée
Exemples de résultats
Conclusion: vers une approche systémique
37
A range of available methods
Physical variability (soil, climatic zone)
Methods based on cropping practices
Methods based on fluxes of matter and energy
SIRIS ranking;IDEA
INDIGO
Tem
po
ral
vari
abil
ity
Static
Mean environment
Local environment
Agri-environmental indicators
Static
Dynamic
Life cycle assessment
38
Why use biophysical models ?
0
1
2
3
4
5
6
7N
ote
d'im
pact
Oilseed rape Sugar Beet Maize
Châlons
Toulouse
DijonChâlons
Toulouse
DijonChâlons
Dijon
Impacts on “fresh water” target, across soil and crop types (model-based)
Ph. D. thesis by L. Mamy, 2004
GM cropnon-GM crop
Low risk7
0
2
4
6
8
10
Châlons
Toulouse
DijonChâlons
Toulouse
DijonChâlons
Dijon
Values of indicator I-Phy for the chemical weeding of GM and non-GM crops
39
Application to natural systems: a source of controversy
LCA of bio-diesel from oilseed rape
N2O
emission
kg/ha/yr
NH3
emission
kg/ha/yr
NO3
leaching
kg/ha/yr
Report by
IFEU/UBA
1992-Germany
~3 0 ~70
Report by
Ecobilan
1993-France
~0.3 0 negligible
« Ecobalance of
oilseed rape»
1996-INRA
~0.1 13 8
40
From field to production system: PRAITERRE
Typology and drivers of farms
Impact assessmentEconomic functions
Pilot farmsSupport for innovations
Adoption of innovations
Impact assessmentEconomic functions
Posterior models Simulation of future environmental impacts Economic analysis
Impact assessmentEconomic functions
Prior modelsSelection of
suitable innovationsAgri-
environmental engineering
Innovative systems design
Project coordinated by G. Lemaire (INRA Lusignan), and funded for 2006-2008.
41
Using straw for combined heat and power production
Global warming impact of one litre of bio-ethanol produced with either pure natural gas or 50% wheat straw. Direct emissions (field)are estimated with a biophysical model, including climate variability.
42
Eat local: common sense or real progress?
Life cycle impacts of the production of one litre of milk produced by cows fed with locally-produced oilseed rape cake or imported soymeal.(Lehuger, S., Master's dissertation, 2005)
0
20
40
60
80
100
Ressou
rces
Effet d
e se
rre
Couche
d'ozo
ne
Tox. h
umaine
Ecoto
x. Aqu
a.
Ecoto
x. Aqu
a. mar
ine
Ecoto
x. te
rrestr
e
Pol. p
hotoch
imiqu
e
Acidific
ation
Eutro
phisa
tion
%
Soja
Colza ITK céréalier
Colza ITKlaitier
Colzamoyen
43
Research issues in a nutshell
Modelling (and experimenting)
Long-term trends from repeated applications
Gaseous emissions (and depositions)
Generating spatial distributions of input parameters,
and validating regional estimates
Encompassing ecological issues that can hardly be
tackled by life cycle assessment (eg, soil quality)
Expanding physical system to internalize
management rules
Recommended