... Materia
Nicholas Georgescu Roegen (1906-1994)
“Matter matters too”
Combust fossil 1950/99
Materiali 60-95
Acqua 1940-2000
L economia: un sistema (complesso) aperto
NATURAL ENVIRONMENT
Natural resources
Natural sinks and material cycles
Earth s energy
Institutional context (political & organisational
SOCIETY Property rights distribution
Non-market caring services
Culture (traditions, ethical values, etc.)
Technologies and know-how
system, etc.)
Information and Knowledge
ECONOMIC SYSTEM
Natural Resources
Goods and Services (human-made)
Material Wastes and
Emissions
Direct Solar
Energy
Earth s Energy
Information and Knowledge
Money
Enterprises
Homes
Money
Dissipated Heat
Labour force and other
production factors
Open system: human
production processes
Open system: human societies
Closed system: Earth
Isolated system?: Universe
JMAlier: The environmentalism of the poor
In the emerging discipline of industrial
ecology,
researchers view modern
economies, metaphorically, as living
organisms.
Industrial economies “ingest”
raw materials, which are “metabolized” to
produce goods and services, and they
“excrete” wastes in the form of discarded
materials and pollution.
WRI 2000, p 1
Bilanciamento di input e output
INPUT
Materia
nazionale prelevata
(utilizzata):
SISTEMA ANTROPICO NAZIONALE
Accumulo di stock
• combustibili fossili
• minerali
• biomasse
Materia
nazionale prelevata e
non utilizzata
Importazioni
(materie prime e
“prodotti compositi”)
Flussi indiretti
associati
alle
importazioni
Aldo Femia
OUTPUT
Restituzione
all’ambiente:
TROUGHPUT
Riciclaggio
• emissioni in aria
• emissioni in acqua
• discariche
• usi dissipativi
• perdite
Materia
nazionale prelevata e
non utilizzata
Esportazioni
Flussi indiretti
associati
alle
esportazioni
Istat, Direzione Centrale della Contabilità Nazionale
Bilancio materiale dell’economia italiana
anno 1997
Importazioni
289
Esportazioni
111
Accumulo di stock
467
di cui:
Materie prime e semilav.
276
Prodotti finiti
13
di cui:
Infrastrutture di trasporto ed edifici
Estrazione interna
Macchinari
di materiali utilizzati
Altri beni durevoli
616
Variazione delle scorte
Animali vivi
di cui:
Combustibili fossili
290
13
8
157
-1
20
Minerali
409
Biomasse
187
Emissioni
480
di cui:
Anidride carbonica
Altre emissioni atmosferiche
Emissioni in acqua
Input ausiliari
457
12
11
677
Rifiuti deposti in discarica
di cui:
Aria per combustione,
56
Utilizzi dissipativi di prodotti e perdite
respirazione,
decomposizione
574
Acqua per
abbeveramento
103
dissipative
144
Altri output gassosi
331
di cui:
Vapore acqueo da
combustione
250
Anidride carbonica e vapore
7
Discrepanza statistica
Aldo Femia
acqueo da respirazione
81
Istat, Direzione Centrale della Contabilità Nazionale
SOME USEFUL DEFINITIONS
Hidden material flow: This is the portion of the total material requirement
that never enters the economy.
It is the natural resource use that occurs when providing those commodities
that do enter the economy.
The hidden material flow comprises two components, ancillary flows and
excavated or disturbed flows.
Ancillary material flow. This is the material that must be removed from the
natural environment, along with the desired material to obtain the desired
material.
Some examples are the portion of an ore that is processed and discarded to
concentrate the ore and
the plant and forest biomass that is removed from the land along with the logs
and grain, but is later separated from the desired material before further
processing.
SOME USEFUL DEFINITIONS
Excavated and/or disturbed material flow.
This is material moved or disturbed to obtain a natural resource, or to
create and maintain infrastructure.
Included in this category is the overburden
that must be removed to permit access to an ore body,
the soil erosion from agriculture,
and the material moved in the construction of infrastructure
(e.g. highway or a building,)
or in the dredging of harbors and canals
For simplicity, both ancillary and excavated or disturbed material have
been
combined into the single category of hidden material, even though they
can
have markedly different environmental impacts.
SOME USEFUL DEFINITIONS
Hidden flows have been calculated
for six categories of material flows:
- fossil fuels,
- metals and industrial minerals,
- construction materials,
- renewable natural resources,
- infrastructure creation and maintenance, and
- soil erosion.
MFA
Direct Material Input (DMI).:
This is the flow of natural resource commodities that enter the industrial
economy for further processing.
Included in this category are
grains used by a food processor, petroleum sent to a refinery, metals used by a
manufacturer, and logs taken to a mill
Total Material Requirement (TMR):
This is the sum of the total material input and the hidden or indirect material
flows, including deliberate landscape alterations.
It is the total material requirement for a national economy,
including all, domestic and imported natural resources.
The TMR gives the best overall estimate for the potential environmental impact
associated with natural resource extraction and use.
RESOURCE FLOWS: THE MATERIAL BASIS OF INDUSTRIAL ECONOMIES p.8
ADRIANSEE et AL. 1997 World Resource Institute
DomesticMaterialConsumption:=DomesticExtraction+IMP–EXP
DMC=DE+IMP-EXP
DMC+EXP=DE+IMP
DE+IMP:=DMI
DomExtr+Imports=:DirectMatInput
TMR procapite
110
100
90
USA
80
70
60
50
40
Paesi Bassi
Germania
Giappone
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
30
World Resource Institute, Adriansee et. Al 1997
Composizioni del TMR pc per il 1991
100
NASCOSTI
20
DIRETTI
40
ESTERI
60
DOMESTICI
Tonnellate pro-capite
80
Germania
Giappone Paesi Bassi
USA
Composizione del DMC pro-capite nel 2000
DMC e DE per unità di territorio
Input Materiale Diretto (DMI) Italia 1980-2001, tonnellate
1.200.000.000
1.000.000.000
800.000.000
Estrazione Interna Utilizzata
600.000.000
400.000.000
Importazioni
200.000.000
2001
2000
1999
1998
1997
1996
1995
1994
1993
1992
1991
1990
1989
1988
1987
1986
1985
1984
1983
1982
1981
1980
-
Fabbisogno Materiale Totale (TMR), Italia 1980-2001, tonnellate
2.500.000.000
2.000.000.000
1.500.000.000
Flussi totali dovuti alle Importazioni
1.000.000.000
Estrazioni interne totali
500.000.000
2001
2000
1999
1998
1997
1996
1995
1994
1993
1992
1991
1990
1989
1988
1987
1986
1985
1984
1983
1982
1981
1980
-