1 a proposal to review the emergy methodology in order to make possible a proper assessment of...
TRANSCRIPT
1
A proposal to REVIEW the EMERGY METHODOLOGY in
order to make possible a
PROPER ASSESSMENT
of sustainable rural systems
Laboratory of Ecological Engineering, Food Engineering School,
State University of Campinas,Campinas, SP, Brazil
Enrique Ortega, Fabio Takahashi,
José Maria Gusman,Luis Alberto Ambrosio
Support:
2
PROBLEM
In the Northern Hemisphere, the agriculture was transformed into a very simple system due to the intensive use of industrial chemicals and machinery in substitution of biological processes and local labor.
Because of that, the emergy assessment of rural systems lost its inherent complexity.
For the correct assessment of ecological farming the excluded factors must be considered.
PROPOSAL
3
INTRODUCTION
The research at the Laboratory of Ecological Engineering deals with the emergy diagnosis of Food Production and Consumption Systems and the design of new models for rural systems.
At the beginning of activities in 1994, the emergy methodology was applied to conventional chemical farming systems.
In 1998, the research focus shifted to soybean farming, the most important agricultural system in Brazil. Soybean is produced in many types of farms, some of them are ecological farms.
4
During the data collection it was discovered that:
• In family managed ecological farms, an important objective was the maintenance of local labor;
• The native vegetation is preserved because it supplies materials and services to the peasant’s family;
• Regional feedback inputs can be renewable or partly renewable;
• Ecological farms produce environmental services.
• Chemical farms produce deleterious externalities.
5
It was concluded that there were two main soybean production models, both with two variants:
(a) Biological model - agro-ecological farming- organic farming
(b) Chemical model - inputs intensive farming- biotechnological farming
It was necessary to work with farm typology, a novelty in emergy analysis. In this presentation the farming models studied will be described.
6
The emergy methodology needs to be actualized, it demands always to be improved!
The suggestion of considering the inputs specific renewability was presented at the 4th International Workshop Advances in Energy Studies, in 2002.
In the 4th Emergy Conference, which took place in 2006, it was presented the idea that information is the key input for Brazilian soybean system and a form to calculate it.
In this meeting, the main contribution is that farm diagnosis should consider impact absorption area using concepts of ecological footprint method and global warming mitigation.
7
The first reference to agriculture emergy analysis was a chapter of the book Energy in Agriculture (Odum, 1984).
After that, in Emergy Folio #4, Brandt-Williams & Odum (2002) presented a very similar systems diagram.
METHODOLOGY HISTORY
Figure 1 shows the diagram used for the emergy analysis of the Agriculture of Florida.
8
Environ-ment
Fuel Goods & Services
Farm production
Soil
Labor PotashElec-tricity
LimePesti-cides
Phos-phate
Nitro-gen
Evapotranspiration
Evaluated product
Figure 2. A systems diagram with 11 inputs and 1 product was applied to 22 crops (Emergy Folio 4. Agriculture of Florida)
9
In 1997, Brandt-Williams and Odum wrote a paper to explain the procedure to make the emergy assessment of agriculture. This work became a chapter of the book Ecological Engineering and Sustainable Agriculture that was published in Portuguese on the internet.
The following diagrams belong to this book.
http://www.fea.unicamp.br/docentes/ortega/livro/index.htmwww.fea.unicamp.br/docentes/ortega/livro/C03-SherryOdum.pdf
10Figure 1a. Energy flows diagram of an Agriculture system.
Rain
Wind
SunVegetable cultivation
Soil & nutrients
Farm assets
Run-off
Lime Fertilizers FuelsHuman labor
Goods & services
Market
Evapo-transpiration
Solar energy
Albedo
Low intensity dispersed energy
Production
Pesticides
Sales
Agriculture system
11
Figure 1b. Nomenclature of aggregated flows.
Vegetable cultivation
Soil & nutrients
Farm assets
RRenewable
natural resources
Dispersed energy
Production
Agricultural system
NNon-renewable
natural resources
MMaterials and Fuel
SLabor and Services
F=M+SEconomy Feedback
I=R+NNature input
Y=I+FTotal Emergy
EProduct Energy
12
Figure 1c. Soil as non-renewable resource.
Environmental work
Dispersed energy
N
Agricultural system
MMaterials and Fuel
SLabor and Services
F=M+SEconomy Feedback
I=R+NNature input
Y=I+FTotal emergy
EProduct Energy
RRenewable resources
NNon-renewable natural assets
Economic useR
M SVery slow production
Very rapid consumption
13
Figure 1d. Resumed diagram showing aggregated flows of inputs and one output.
NY=I+FEconomic use of the
ecosystem space
R
M S
14
These two approaches didn’t consider:
• The environmental services provided by farm’s preserved forest and wetlands;
• Biologically fixed nitrogen and soil minerals mobilized by micro-biota;
• That part of production destined to local population; • Recycling; • The possibility of co-products, as for example,
second crops; • Waste, emissions, rural exodus, toxic substances,
deaths by intoxication, biodiversity loss, human culture degradation and other outputs.
15
Ortega et al. (2002a, 2002b), concerned with the distortion between reality and emergy indices, proposed the use of input’s renewability for emergy flows calculation and also new indices.
This perspective is described in the next figures.
The feedback could have a renewable part (FR) and non-renewable part (FN):
F = FR + FN = (MR + SR ) + (MN + SN)
MR = MiR = (Reni) (Mi)
MN =MiN =(1-Reni) (Mi)
M = MR + MN
Each Material and Service has its own renewability:
S = SR + SN
16Figure 3a. A broad vision of agricultural systems.
Environmental work
Degraded energy
Agricultural system
M
S
F=M+SEconomy Feedback
I=R+NNature inputs
Y=I+F
Products Energy
R1
Local renewable resources
NCNature assets
R
M RVery slow production
Very slow consumption
R
Services including external labor and information
Materials and fuel
R3
Atmosphere & soil minerals renewable resources
QFarm
Assets HHuman Assets
R2
Regional renewable resources
$Money
$ in
$ out
LLocal labor
S
Environmental services
Direct environmental forces
Very slow production
Total emergy used
Output
Low values
Ecological Agriculture
Biological model: Agro-ecological farming.
17Figure 3b. A broad vision of agriculture systems.
Environmental work
Degraded energy
N
Agricultural system
M
S
F=M+SEconomy Feedback
I=R+NNature inputs
Y=I+F
Products Energy
R1
Local renewable resources
NCNature assets
Agriculture as economic use of
geographic spaceR
M RVery slow production
Very rapid consumption
Very slow consumption
R
Services including external labor and information
Materials and fuel
R3
Atmosphere & soil minerals renewable resources
QFarm
Assets HHuman Assets
R2
Regional renewable resources
$Money
$ in
$ out
LLocal labor
S
Destruction
Emissions, efluents and residues energy
Environmental services
Direct environmental forces
N
Very slow production
Biodiversity lossSoil erosion
Toxic substancesRural exodusCultural loss
Total emergy used
Output
Transition to chemical farming.
18Figure 3c. A broad vision of agriculture systems.
Environmental work
Degraded energy
N
Agricultural system
M
S
F=M+SEconomy Feedback
I=R+NNature inputs
Y=I+F
Products Energy
R1
Local renewable resources
NCNature assets
Agriculture as economic use of
geographic spaceR
MVery rapid consumption
Services including external labor and information
Materials and fuel
QFarm
Assets
R2
Regional renewable resources
$Money
$ in
$ out
S
Destruction
Emissions, efluents and residues energy
Direct environmental forces
N
Biodiversity lossSoil erosion
Toxic substancesRural exodusCultural loss
Total emergy used
Output
X
X
Chemical model: inputs intensive farming.
19
Figure 3d. Aggregated flows diagram. Products Energy
Economic use of geographic space as chemical agriculture
M R S
Emissions, efluents and residues energy
N
R
Very rapid consumption
R
Very slow production
interactionR
N FNFR
interactionR
N FNFR
interactionR
N FNFR
Reni
Mi
Reni
Ri
Reni
Si
F = FR + FN
Biodiversity lossCO2, Rural exodusToxic substances
Cultural lossSoil erosion
OutputDestruction N
Environmental servicesVery slow production
20Figure 4. A new diagram proposed to study agricultural systems (Ortega et al., 2002a, 2002b)
Environmental work
Agriculture system
I=R+NNature inputs
R1
Local renewable resources
BNature assets
Very slow production
Very slow consumption
R3
Atmosphere & soil minerals renewable resources
R2
Regional renewable resources
Products Energy
M LL S
Emissions, efluents and residues energy
Environmental servicesVery slow production
Biodiversity lossCO2, Rural exodusToxic substances
Human culture lossSoil erosion
Output
N
R
Very rapid consumption
R
interactionR
N FNFR
Reni
Mi
Reni
Reni
Si
M
S
F=M+SFeedback from Economy
Services including external labor and information
Materials and fuel
QFarm
Assets HHuman Assets
$Money
$ in
$ out
LLocal labor
DestructionN
Economic use of geographic space as agriculture
interactionR
N FNFR
Direct use
Our first idea for a General Model(It includes biological & chemical systems).
21Figure 5. Proposal of a more complete systems diagram measuring INFO, GW, WT and LR (Ortega, 2006).
Water and mineral
resourcesfrom soil
(M&S)R
Renewable energy
Nitrogen from
atmosphere
People
(M&S)N
Soil
Local processing
Environmental Services
Negative externalities
Products
Plantation
Forest reserve
Regional biodiversity
Local population
Materials and Services
ProductsSun, Moonand Earth´s internal heat
Albedo
Residues
InfoN
Local resources
CO2 in excess
captured
Acid deposition due to NOx
and SOx liberation
Local and global climate change
Not filtered UV radiation
InfoR
Waste treatment
Loss Recovery
Additional services
Info
WT
LR
GW
22
Rural space biocapacity
Rural production unit(s)
Earth deep heat
Moon-Earth gravity force
Sun energy
Nitrogen biológically
fixed
Soil mineralsbiolocally mobilized
Industrial urban centers
Environmental services for external use
Industrial products and services
Residues & emissions
Local population
Environmental services locally used
Residues & emissions
Local resources used above
recovering rate
Crop lands & grazing lands
Wetlands, prairies, swamps
Poly-culture
Native vegetation
(productive)
Past eras ecosystems
Bio-mass
External consumption
Biological diversity
Raw materials without added value
Infra-structure
Industrial products obtained with non-
renewable resources
Animal husbandry
PeopleProcessed
products
Local consumption
Treatment & recycling
Crops, cattle and forestry products
Negative externalities (receptor damage)
$
$
Infra-structure
Money
Culture
CultureInformation
External inputs Recycled
residues
Human labor
Geophysical, thermo-chemical processes
Biocapacity of areas without human control
Emissions and industrial wastes with global impact
Petroleum, gas, coal
Recycling
Extraction, Power plants, Petrochemical and Pharmaceutical industries, Metalurgy, etc.
Global resources used above
reovering rate
Minerals, wood
Net yield of energy and materials
Feed-back
Biological diversity
“non productive” biomas of present era
Greenhouse gases,
acid aerosols
CO2Soil, wood
Solid wastes, effluents and emissions
Transfer controls
Figure 6. An even more complete systems diagram for an agricultural system.
23
Rural space biocapacity
Rural production unit(s)
Earth deep heat
Moon-Earth gravity force
Sun energy
Nitrogen biológically
fixed
Soil mineralsbiolocally mobilized
Crop lands & grazing lands
Wetlands, prairies, swamps
Poly-culture
Native vegetation
(productive)
Biological diversity
Animal husbandry
External inputs Recycled
residues
Human labor
Greenhouse gases,
acid aerosols
Residues & emissions
Local population
Environmental services locally used
Local resources used above
recovering rate
Infra-structure
PeopleProcessed
products
Local consumption
Treatment & recycling
Crops, cattle and forestry products
$Money
CultureInformation
Recycling
Solid wastes, effluents and emissions
Soil, wood
Raw materials without added value
Environmental services for external use
Negative externalities (receptor damage)
Net yield of energy and materials
Step by step building-up of the complex diagram
24
Rural space biocapacity
Rural production unit(s)
Earth deep heat
Moon-Earth gravity force
Sun energy
Nitrogen biológically
fixed
Soil mineralsbiolocally mobilized
Environmental services for external use
Residues & emissions
Local population
Environmental services locally used
Local resources used above
recovering rate
Crop lands & grazing lands
Wetlands, prairies, swamps
Poly-culture
Native vegetation
(productive)
Biological diversity
Raw materials without added value
Infra-structure
Animal husbandry
PeopleProcessed
products
Local consumption
Treatment & recycling
Crops, cattle and forestry products
Negative externalities (receptor damage)
$Money
CultureInformation
External inputs Recycled
residues
Human labor
Recycling
Net yield of energy and materials
Greenhouse gases,
acid aerosols
Solid wastes, effluents and emissions
Soil, wood
Industrial urban centers
Residues & emissions
External consumption
$
Infra-structure
Culture
Transfer controls
Past eras ecosystems
Bio-mass
Industrial products obtained with non-
renewable resources
Geophysical, thermo-chemical processes
Petroleum, gas, coal Extraction, Power plants, Petrochemical and
Pharmaceutical industries, Metalurgy, etc.
Global resources used above
reovering rate
Minerals, wood CO2
Biological diversity
“non productive” biomas of present era
Biocapacity of areas without human controlIndustrial products and services
Emissions and industrial wastes with global impact
Feed-back
25
OUR SUGGESTIONS
(a) To use the renewability of each input in the Emergy Flows and Emergy Indices calculations;
(b) To consider as additional renewable inputs those flows that are produced by biodiversity, such as soil minerals obtained by deep roots and micro-biota and chemicals produced by symbiotic biota;
26
• The real productivity without the consideration of top soil erosion and fossil fuel use as positive fact (instead of EYR = (R/F) + (N/F) +1 use R/F instead of ESI =EYR/ELR use B/C=R/N);
(c) To develop indicators that measure:
• Renewable and non-renewable capital;
• Internal flows (local consumption, material recycling, internal services);
• Human labor quality;
• Environmental services loss;
• Negative externalities;
27
(d) To consider Natural Capital, Environmental services, Infra-structure, Financial and Social Resources, Emissions and Waste as new items in the Inputs-Output balance.
(e) To consider the value of Information as input, stock and output;
(f) To discuss the contradiction of using Transformity Tr = (R+N+F)/E as indicator of viability, because low productivity (E) and high erosion farms (N) could have the biggest values!
(g) To consider impact absorption area.
28
APLC
ESLC
LL
Ex
ES
Local consumption
Residues, effluents, emissions
F
Preserved ecosystems
AgricultureProduction
Local labor
APLP
AP
CL
APT
WT
WL
WE
R
EST
Transfor-mation
Greenhouse gases
and Acids
Heat
Cold
F´ F´´
AP
Environmental services
Locally processedagricultural products
Waste and losses from destroyed internal structure
Negative externalities
Human economy feedback: materials & services
Directrenewable resources
Exportedagricultural products
NLNon- renewable local resources
Nitrogen & minerals mobilized by biota
R’
R’’
Other ecosystems resources
Ex
Figure 7. First part of a proposal for a generic diagram.
29
R Global ecosystems
Treatment & recovering systems
Impact absorption: heat, negative externalities, internal structure losses, waste, effluents, emissions
ES
Forested lands of Clean Development Mechanism
F´´´
Cold environment
Negative externalities
Additional feedback from human economy: materials & services
Ex
Environmental services: clear air, clean water, healthy soil,preserved species,stabilized climate.
Area
Area
Area
The second part of the generic diagram: impact absorption area
30
The complete system diagram
APLC
ESLC
LL
Ex
ES
Local consumption
Residues, effluents, emissions
F
Preserved ecosystems
AgricultureProduction
Local labor
APLP
AP
CL
APT
WT
WL
WE
R
EST
Transfor-mation
Greenhouse gases
and Acids
Heat
Cold
F´ F´´
AP
Environmental services
Locally processedagricultural products
Waste and losses from destroyed internal structure
Negative externalities
Human economy feedback: materials & services
Directrenewable resources
Exportedagricultural products
NL
Nitrogen & minerals mobilized by biota
R’
R’’
Other ecosystems resources
R
Global ecosystems
Treatment & recovering systems
ESForested lands of Clean Development Mechanism
F´´´
Cold environment
Greenhouse gases (CO2, CH4, N2O) Heat, Acids, Organic matter, Losses from system internal structure, Toxic substances.
Additional feedback from human economy: materials & services
Clear air and water, healthy soil,preserved species,stabilized climate.Area
AreaArea
Environmental services:
The impact production must fit the impact absorption capacity
31
APLC
ESLC
LL
Ex
ES
F
LA & P
APLP
AP
CL
APT
WA
WL
WE
R
R
GE
GT ES
EST
CDM
TP
GHG
H
F´ F´´´F´´
C
AP
CL
WLT
A’’
Production Area
Impact Absortion Area
A’’
NLC
NLT
NCE
NC
PNL
Ex
The complete system can be represented in a compact form.
It can be seen as a fractal.
32
APLC
ESLC
LL
Ex
ES
F
APLP
AP
CL
APT
WA
WL
WE
R
R
GE
GT ES
EST
CDM
GHG
F´ F´´´F´´
AP
CL
WT
A’’
Production Area
Impact Absortion Area
A’’
APLC
ESLC
LL
Ex
ES
F
APLP
AP
CL
APT
WA
WL
WE
R
R
GE
GT ES
EST
CDM
GHG
F´ F´´´F´´
AP
CL
WT
A’’
Production Area
Impact Absortion Area
A’’
APLC
ESLC
LL
Ex
ES
F
APLP
AP
CL
APT
WA
WL
WE
R
R
GE
GT ES
EST
CDM
GHG
F´ F´´´F´´
AP
CL
WT
A’’
Production Area
Impact Absortion Area
A’’
Chemical Inputs
Agriculture production
Urban consumption
Interconnected fractals
The question is that until today the production-consumption systems have not been planned correctly!
33
R
GE
TRSES
CDM
F´´´
CE
A
AA
Ex
R
GE
TRSES
CDM
F´´´
CE
A
AA
Ex
R
GE
TRSES
CDM
F´´´
CE
A
AA
Ex
APLC
ESLC
LL
Ex
ES
F
Ll
APLP
AP
CL
APT
WT
WL
WE
R
EST
Tr
GHG
Heat
Cold
F´ F´´
AP
NL
R’
R’’
APLC
ESLC
LL
Ex
ES
F
Ll
APLP
AP
CL
APT
WT
WL
WE
R
EST
Tr
GHG
Heat
Cold
F´ F´´
AP
NL
R’
R’’
APLC
ESLC
LL
Ex
ES
F
Ll
APLP
AP
CL
APT
WT
WL
WE
R
EST
Tr
GHG
Heat
Cold
F´ F´´
AP
NL
R’
R’’
Chemical Inputs
Agriculture production Urban
consumption
Area deficit
Area deficit
Area deficit
All the human systems have been built without impact absorption area!
34
APLC
ESLC
LL
Ex
ES
F
Ll
APLP
AP
CL
APT
WT
WL
WE
R
EST
Tr
GHG
Heat
Cold
F´ F´´
AP
NL
R’
R’’
Overshoot possibility!
0
5
10
15
20
25
30
35
40
0 1 2 3 4 5 6 7 8
EIR
Fo
rest
are
a /
fa
rmin
g a
rea
SANPP
SAR
R
GE
TRSES
CDM
F´´´
CE
A
AA
Ex
There is an area deficit!
(Agostinho et al., 2008)
It is up to 6 to 13 times bigger than the crop area!
What is the size of the impact absorption area in agriculture?
Brazilian watershed
(Siche et al., 2007)
(Ulgiati et al., 2001)
Other countries
(Brown et al., 2002)
35
The farm productivity should be compared in a proper basis: as a whole system, including complementary area.
The agro-ecological farm already includes its impact absorption area as preserved natural area that also produces environmental services.
The chemical farm should include the complementary area needed to absorb environmental impact and to produce the environmental services that are lost due to its full conversion to crop land.
Productivity = --------------------------------------------------------Production (kg/year)
Crop area + Impact absorption area (ha)
36
An example of whole system comparison:
Corn production in an agro-ecological farm:
Corn production in a chemical farm:
Productivity = ----------------------------------------------- = ---------------2000 kg/year
Crop area (1 ha) + absorption area (1 ha)
1000 kg/year
ha
Productivity = ----------------------------------------------- = ---------------6000 kg/year
Crop area (1 ha) + absorption area (11 ha)
500 kg/year
ha
This concept helps to explain the so called “Scale Economy” that really works in the opposite sense!
37
Table 1. Classification of Emergy flows
Inputs and services Description
I: Nature contribution R + N
R = R1 + R2 +R3
Renewable resources from nature
Rain;Materials and Services from preserved areas; Nutrients from soil minerals and air.
N: Nature non-renewable inputs Soil and diversity loss (including people).
F: Economy Feedback F = M + S
M: Materials M = MR + MN
MR: Renewable Materials Renewable materials from natural origin.
MN: Non-renewable Materials Minerals, Chemicals, Steel, Fuel, etc.
S: Services (total) S = SR + SN + SA
SR: Labor Services (partially renewable) Labor (family, local and external): SR = SRF + SRL + SRE
SN: Other Services (non-renewable) Taxes, money costs, insurance, etc.
SA: Additional Services (non-renewable) Externalities: effluents, medical and job costs,
Y: Total Emergy Y = I + F
38
Table 2a. Proposals for Emergy Indices
Modified Emergy Indices Formula Concept
Renewability* R* = (R + MR + SR) / Y Renewable/Total
Environmental Loading ratio* ELR* = (N+MN+SN) / (R+MR+SR) Non-renewable/renewable
New Emergy Indices Formula Concept
Labor Services Ratio LSR = SR / S Labor/Services
Labor Empower Ratio LER = SR / Y Labor/Empower
Family farming LWR = SRF / (SRL+SNE) Family labor/Others
Externalities Empower Ratio ExER = SA / Y Externalities/Empower
Cycling ratio CR = C / F Cycling / Feedback
39
Table 2b. Proposals for Emergy Indices
New Emergy Indices Formula Concept
Natural Capital/Economy NC / (IE + FN) Natural Capital / Feedback
Renewable mobilization Benefit =R/F Renewable/Feedback
Non-renewable mobilization Cost =N/F Nonrenewable / Feedback
Systemic Benefit/Cost BC=R/N Renewables /Non-renewables
External resources dependence ED= F/R Feedback/Renewables
Natural Capital rate CN / Time Natural capital change with time
Anthropic rate (IE + FN) / Time Human assets change with time
40
RESULTS & DISCUSSIONAgro-forestry (10 years)
Conventional extensive low productivity
41
The End of Oil Actual and Projected Oil Production
Increasing:N/F, ELR, EIR, Tr, EER
Increasing: %Ren, R/F
Decreasing: %Ren, R/F Decreasing:N/F, ELR, EIR,Tr, EER
CO2 Reduction Actual and Projected CO2 Production
Individualism, capitalismcompetition & exclusion
Community solutions
Support a social & ecological perspective for
42
CONCLUSIONS OR RECOMMENDATIONS
1. If the suggestions proposed here are pertinent, then it is necessary to organize a group to discuss these issues in deep;
2. Give this group a reasonable time (4-6 months) to discuss on the best procedures for this kind of emergy calculation;
3. Disseminate the preliminary results among the emergy researchers to obtain feedback;
4. Write a new folio on Agriculture (General Scope)
43
ACKNOWLEDGEMENTS
• Adriana Pires for egg production system research
• Teldes Albuquerque for Agro-forestry systems research
• Mileine Zanghetin for helping in preparation of PowerPoint presentation
• Feni Agostinho for discussion and graph preparation of forested area needed to absorb the impact of non-renewable feedback from economy
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