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1/22
A more accurate value of ecological footprint for small farms in Brazil
Feni AgostinhoEnrique Ortega
State University of Campinas, Brazil
Raul SicheNational University of Trujillo, Peru
000 51
International Footprint Conference: New Developments In Ecological Footprinting
Methodology, Policy And Practice
8-10 May 2007, City Hall, Cardiff, UK
2/22
Introduction
1. Agriculture is essential to human life maintenance, but besides food and fibers it produces externalities:
2. The objective of this work is to insert externalities in the calculation of footprint and biocapacity. In this first attempt we only studied small farms.
a. Positive externalities or environmental services: water percolation; maintenance of biodiversity (native vegetation areas); climate regulation; soil erosion control; local labor.
b. Negative externalities: water and soil contamination by chemicals; decrease of water percolation and increase of soil loss; greenhouse gases emission (global warming); biodiversity loss; human exodus.
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Nitrogen from
atmosphere
Plantation
Local resources
Products
Forest reserve
Albedo
Water and mineral
resources from soil
CO2
Local and global climate change
Materials and
services
Sun, Rain and Wind
Local processing
Residues
Products
$High quantity of environmental
services
Low quantity of negative
externalities
Local laborRegional
biodiversity
Co-products of the ecological farming model
4/22
Regional biodiversity
Plantation
Products
Forest reserve
Albedo
Nitrogen from
atmosphere
Water and mineral
resources from soil
CO2
Local and global climate change
Materials and services
Sun, Rain and Wind
Residues
Products
$Low quantity of environmental
services
High quantity of negative
externalities
Co-products of the agro-chemical model
5/22
Negative externalities
Negative externalities for UK agriculture (Pretty et al., 2005):
(a) 360 USD/ha/year for conventional agriculture;
(b) 80 USD/ha/year for organic agriculture.
Negative externalities of Brazilian soybean farming (Ortega et al., 2005)
USD/ha/year
Conventional Ecological
Top soil loss 83.0 83.0
Nutrient losses due to erosion 13.6 13.6
CO2 emission 7.8 -
CH4 and NOx emission 52.5 -
Effluent treatment 39.7 -
Intoxication and deaths by pesticides 0.2 -
Rural exodus 50.0 -
Total: 246.8 96.6
6/22Source: Millennium Ecosystem Assessment
Ecosystems services
7/22
Ecosystems services
A key work on positive externalities was published by Costanza et al. (1997), who estimated the value of environmental services for the entire planet as USD 33 trillion per year.
Biomes existing in the farms studied
Value of ecosystems services in USD/ha/year (Costanza et al., 1997)
Lakes/Rivers 8457
Tropical forest 1745
Grass/Rangelands 158
Cropland 38
Biomes considered in Costanza’s work were: (a) Terrestrial: Forest, Grass/Rangeland, Wetland, Lakers/Rivers, Desert, Tundra, Ice/Rock, Cropland, Urban; (b) Marine: Open ocean, Coastal.
8/22
Study cases: small family farms
Two models of production were compared: ecological model and conventional or chemical model. Three farms were studied:
(a) Duas Cachoeiras farm – ecological model (29.7ha);
(b) Santa Helena farm – conventional model (15.5ha);
(c) Três Lagos farm – conventional model (25.2ha).
Brazil São Paulo state
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New assumptions in ecological footprint assessment
Changes made in the present paper
Traditional Ecological Footprint
Equivalence factors (EQF) were calculated with NPP as suggested by Venetoulis & Talberth (2005)
The EQFs are based on Earth’s potential to supply resources for humanity (agricultural suitability index)
Externalities accounted as Emergy (Odum, 1996)
Not considered
Built areas in farms doesn’t have gardens and parks, only roofs and roads
Urban areas have biocapacity due to gardens and parks
All green areas were considered as CO2 absorbers (49 kg C/ha/yr; IPCC, 2004)
Only forest areas are accounted (950 kg C/ha/yr)
Agrochemicals accounted as Emergy Not considered
10/22
Biome Biome service value
(USD/ha/yr)
Duas Cachoeiras farm
Santa Helena farm
Três Lagos farm
ha USD/yr ha USD/yr ha USD/yr
Lake 8457 0.16 1353.12 0.18 1522.26 0.44 3721.08
Forest 1745 7.79 13593.55 4.59 8009.55 1.98 3455.10
Grass/Rangeland
158 12.49 1973.42 1.43 225.94 18.36 2900.88
Cropland 38 7.54 286.52 7.50 285.00 4.16 158.08
Total (USD/yr): 17206.61 10042.75 10235.14
Total farm area (ha) 29.70 15.50 25.20
Total (USD/ha/yr): 579.35 647.92 406.15
11/22
Results
Land use Duas Cachoeiras farm (29.7ha)
Santa Helena farm (15.5ha)
Três Lagos farm (25.2ha)
Forest 7.79ha 4.59ha 1.98ha
Lake 0.16ha 0.18ha 0.44ha
Crop 7.54ha 7.50ha 4.16ha
Meadow 3.96ha - -
Pasture 8.53ha 1.43ha 18.36ha
Construction 1.72ha 1.84ha 0.29ha
Negative Ext. 96 USD/ha/yr 247 USD/ha/yr 247 USD/ha/yr
Positive Ext. 579 USD/ha/yr 647 USD/ha/yr 406 USD/ha/yr
(26.2%)
(0.6%)
(25.4%)
(13.3%)
(28.7%)
(5.8%)
(29.5%)
(1.2%)
(48.3%)
(9.2%)
(11.8%)
(7.8%)
(1.7%)
(16.6%)
(72.8%)
(1.1%)
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Results
Duas Cachoeiras farm[nha]
Santa Helena farm[nha]
Três Lagos farm[nha]
1. Traditional method (with the use of NPP for EQFs calculation)
Biocapacity 56.22 27.30 42.18
Ecological footprint 17.38 17.99 21.50
Ecologic balance 38.84 9.30 20.69
2. Enhanced method (considering negative and positive externalities)
Biocapacity 73.63 37.46 52.54
Ecological footprint 18.66 25.74 28.94
Ecologic balance 54.97 11.72 23.61
The unit “national hectares” was used instead of “global hectares” because we used national data to calculate the yield factor and the Brazilian emergy density to account the negative externalities and the environmental services.
13/22
Results
There is a positive balance for all systems using the two methodologies; it increases in the case of the ecological farm.
Results in nha (national hectares)
Duas Cachoeiras farm
Santa Helena farm
Três Lagos farm
1. Traditional method (with use of NPP for EQF’s calculation)
Biocapacity 56.22 27.30 42.18
Ecological footprint 17.38 17.99 21.50
Ecologic balance 38.84 9.30 20.69
2. Enhanced method (considering negative and positive externalities)
Biocapacity 73.63 37.46 52.54
Ecological footprint 18.66 25.74 28.94
Ecologic balance 54.97 11.72 23.61
(+17.41)
(+1.28)
(+16.13)
(+10.16)
(+7.75)
(+2.41)
(+10.36)
(+7.44)
(+2.92)
14/22
Results
Agroecological farm: best performance in biocapacity, footprint and ecologic balance using the two methodologies when compared with the other farms studied.
Results in nha (national hectares)
Duas Cachoeiras farm
Santa Helena farm
Três Lagos farm
1. Traditional method (with use of NPP for EQF’s calculation)
Biocapacity 56.22 27.30 42.18
Ecological footprint 17.38 17.99 21.50
Ecologic balance 38.84 9.30 20.69
2. Enhanced method (considering negative and positive externalities)
Biocapacity 73.63 37.46 52.54
Ecological footprint 18.66 25.74 28.94
Ecologic balance 54.97 11.72 23.61
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Results
BC/EF = biocapacity/footprint
Farm BC (nha) EF (nha) BC/EF
Duas Cachoeiras 73.6 18.6 3.9
Santa Helena 37.4 25.7 1.4
Três Lagos 52.5 28.9 1.8
•The ecological farm produces almost 4 times its footprint;
•The conventional chemical farm produces only 1.6 times its own footprint.
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Conclusions
1. Agroecology improves the farm sustainability by increasing
biocapacity and reducing ecological footprint. Consequently the
ecological farm studied here is doubtlessly an example to be
followed;
2. Negative externalities and ecosystem services proved to be
important factors in EF calculations. Thus, it is extremely necessary
to carry on further studies about their calculation;
3. The three systems studied are small family farms and are not
representative of Brazilian agricultural business. The farmers sold
products in local markets and preserve native forest; therefore
they keep some biodiversity. Profit is small and it is used to
maintain the system under production. These facts explain why the
indicators observed are so similar.
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It is urgent to evaluate the big chemical farms in Brazil (soybean, sugar-cane, orange, coffee and cattle) using Ecological Footprint and considering negative externalities and ecosystem services.
Source:Ortega, 2007c
Ecological farmUSD/ha/year
Chemical farmUSD/ha/year
Soybean sales 500 650
Corn and Wheat sales 600 800
Environmental services
400 0
Sales 1100 1450
Integral benefits 1500 1450
Production costs 400 800
Externalities 0 360
Ideological pressures 0 240
Total costs 400 800
Economic profit 700 650
Net integral benefit 1100 50
Recommendation
18/22
Source:Ortega, 2007c
Ecological farmUSD/ha/year
Chemical farmUSD/ha/year
Soybean sales 500 650
Corn and Wheat sales 600 800
Environmental services
400 0
Sales 1100 1450
Integral benefits 1500 1450
Production costs 400 800
Negative externalities 0 360
Ideological pressures 0 240
Total costs 400 1400
Economic profit 700 650
Integral or due profit 1100 50
Assumptions for future studies
Income depends on size and not on productivityEcological farmer = 1100 USD/ha/year x 20 ha = 22 000 USD/year
Chemical farmer = 50 USD/ha/year x 2000 ha =100 000 USD/year
Difference is bigger because externalities are not paid
Chemical farmer= 650 USD/ha/year x 2000 ha =1 300 000 USD/year
19/22Soybean production in Central Brazil
20/22
Biodiversity destroyed
Hydrologic damages
Rural exodus
Poisonous substances
Hunger and
poverty
Gas for greenhouse
Effect
Cheap meat, milk, eggs for
Europeans
+
Unfair prices for local ecological farmers
High footprint in foreign countries
21/22
Acknowledgements
The authors are grateful to CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior)
and to CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico) for their financial support.
22/22
Externalities FP and BC calculation
Positive externalities (ecosystem services):
Negative externalities:
Chemical model externalities = 246.8 USD/ha/yr (Ortega et al.,2005)
Ecological model externalities = 96.6 USD/ha/yr (Estimated);
Area = area with crop production or pasture;
Biome value = data from Costanza et al. (1997);
Brazilian emdollar = 3.30E+12 seJ/USD (Ortega, 2007b);
Biome area = biome area present in the farm;
Brazilian emergy density = 3.26E+15 seJ/ha/yr (Ortega, 2007b).
Externality value [USD/ha/yr] * Brazilian emdollar [seJ/USD] * Area [ha]
Brazilian emergy density [seJ/ha/year]
Footprint [nha] =
23/22
Chemicals footprint (Zhao et al., 2005)
Transformities of chemical inputs:
Fertilizer = 4.78E+13 seJ/kg ( Brandt-Williams, 2002);
Pesticide = 2.49E+13 seJ/kg (Brown and Arding, 1991);
Vaccine = 3.30E+12 seJ/USD (Ortega, 2007b);
Brazilian emergy density = 3.26E+15 seJ/ha/yr (Ortega, 2007b).
Chemical input [kg or USD/yr] * Transformity [seJ/kg or USD]
Brazilian emergy density [seJ/ha/yr]
Footprint [nha] =
Footprint = [seJ/year] / [seJ/ha/year] = ha
24/22
References
Costanza R, D’Arge R, De Groot R, Farber S, Grasso M, Hannon B, Limburg K, Naeem S, O’Neill RV, Paruelo J, Raskin RG, Sutton P, van den Belt M. 1997. The value of the world’s ecosystem services and natural capital. Nature. 387: 253-260.
IPCC. 2004. Intergovernmental Panel on Climate Change. 2004. Inter-annual and decadal variability of atmospheric CO2 concentrations. In:
The Special Report on Land Use, Land-Use Change, and Forestry. Available in: http://www.grida.no/climate/ipcc/land_use/020.htm. Date of access: 16/12/2006.
Millennium Ecosystem Assessment. Available in: http://www.maweb.org/en/index.aspx. Date of access: 10/02/2007.
Odum HT. 1996. Environmental Accounting, Emergy and Decision Making. J. Wiley, NY.
25/22
References
Ortega E. 2007c. What is INFO? The role of information in agriculture. Proceedings of IV Emergy Conference, University of Florida, Gainesville, USA. In press.
Ortega E, Cavalett O, Bonifácio R, Watanabe M. 2005. Brazilian Soybean Production: emergy analysis with an expanded scope. Bulletin of Science, Technology & Society. 25: 323-334.
Pretty JN, Ball AS, Lang T, Morison JIL. 2005. Farm costs and food miles: An assessment of the full cost of the UK weekly food basket. Food Policy. 30: 1 – 19.
Venetoulis J, Talberth J. 2005. Ecological footprint of Nations (2005 Update): sustainability indicators program. Redefining Progress. Available in: www.redefiningprogress.org Date of access: 11/11/2006.