An Environmental Accounting Model for a Natural Reserve
Francesco Marangon*, Maurizio Spoto# and Francesca Visintin*
* Department of Economics, University of Udine, Via Tomadini 30/a I-33100 Udine, Italy
# Miramare Natural Marine Reserve, Viale Miramare 349, I-34100 Trieste, Italy
E-mail: marangon@uniud.it
Abstract: The implementation of environmental accounting
in a Natural Reserve produced some significant results in
terms of restrictions. First of all, environmental accounting
introduced a limitation in scale, which was inapplicable on a
micro scale. A second restriction concerned the physical unit
measure that was used instead of a monetary unit measure.
Finally, a third limitation was related to the fact that
environmental accounting only takes costs into account, and
not environmental benefits. These three limitations led us to
develop an environmental accounting model that considered
both consumed and produced resources in the Natural
Reserve. The model aimed at supplementing monetary
accounting (based on cost and revenue) with environmental
accounting, which not only reflects environmental cost, but
also environmental revenue; i.e. environmental benefit. The
difference between costs and benefits, both economic and
environmental, assessed the value produced or consumed by
the Natural Reserve.
Keywords: natural marine reserve, environmental
accounting, ecosystem functions, LTFP.
environmental accounting model that considered
resources both consumed and produced in the MNMR.
The model aimed at supplementing monetary accounting
(based on cost and revenue) with environmental
accounting, which not only reflects environmental cost,
but also “environmental revenue”; i.e. environmental
benefit. The difference between economic and
environmental costs and benefits assessed the value
produced or consumed by the MNMR. The model
assesses flows between the biosphere and technosphere
(Figure 1) [1] and is indicated as a “Natural resources
asset account” [2], [3]. The study analysed two of the
four flows: the biosphere-technosphere flow, which
assessed environmental benefits and economic revenue;
and the technosphere-biosphere flow, which assessed
environmental and monetary costs.
BIOSPHERE
TECHNOSPHERE
BIOSPHERE
IMPORTS
WASTE
FAMILIES
TRANSPORT
INDUSTRY
AGRICULTURE
STOCKS2
STOCKS1
DECOMPOSERS
CONSUMERS
PRODUCERS
SOIL
WATER
AIR
WATER
SOIL
PRODUCERS
CONSUMERS
DECOMPOSERS
STOCKS1
STOCKS2
TECHNOSPHE
Since 2004 the University of Udine (Italy) and the
Italian branch of the World Wildlife Fund have worked
together to establish an environmental accounting model
for the Miramare Natural Marine Reserve (Trieste, Italy)
(MNMR). The implementation of environmental
accounting has produced some significant results in terms
of limitations. First of all, environmental accounting
introduced a limitation in scale. The Namea (ISTAT1)
and Epea (EUROSTAT) models are effective on a macro
scale, but are inapplicable on a micro scale. This is the
case in natural areas. Natural resource accounting of
natural resources overcomes this limitation, but
introduces a second restriction: the implementation of a
physical unit measure instead of a monetary unit
measure. Finally a third limitation regards the accounting
of environmental costs, but not environmental benefits. If
environmental benefits are ignored, the environmental
accounting system will only take the effects of the
resources consumed into account, but not the resources
produced by ecosystems.
In section II the methodology is outlined and the
environmental accounting model is given. In section III
there is a brief description of the Miramare Reserve and
there is an illustration of how the model was adjusted to
the specific case. Section IV provides an analysis of the
results and section V concludes.
AIR
I. INTRODUCTION
AGRICULTURE
INDUSTRY
TRANSPORT
FAMILIES
WASTE
IMPORTS
Figure 1: Biosphere – technosphere flow matrix
TABLE I: ENVIRONMENTAL ACCOUNTING MODEL FOR THE MNMR
Asset accounts for the MNMR
Natural stock
Natural flow account
account
Costs:
Natural stock:
Benefits:
monetary
quantity
monetary
(park overheads)
(park revenues)
quality
environmental
environmental
(environmental costs)
(environmental benefits)
II. METHODOLOGY
We can see that the environmental accounting structure
for the MNMR is the same as that of the natural
resources asset account, and includes a natural capital
dimension (natural stock account) and a flow dimension
(natural flow account) (Table I).
The three limitations mentioned above (scale, unit
measure and cost but not benefit) led us to develop an
III. RESULTS
1
Istituto nazionale di statistica, National Institute of Statistics of
Italy.
La A Ministry of Environment decree established the
Miramare Natural Marine Reserve in 1986, and its
management was assigned to the Italian branch of the
World Wildlife Fund. The MNMR is located in the Gulf
of Trieste, which is situated in the northern part of the
Adriatic Sea. The land surface covers 30 ha., while the
surrounding sea area is 90 ha. The environment is marine
and coastal, and the land is rocky along the coast.
Information regarding the MNMR has been disseminated
in the surrounding area by means of scientific research,
environmental education projects, and local and national
media exposure. Moreover, projects have been set up
regarding local tourist management and fishing
regulation.
A. Natural stock account
It is difficult to assess the value of the Reserve’s natural
capital and its natural resources (water, flora, fauna and
soil)., and at this stage of our research we have not yet
reached an adequate estimate. To do so would require an
accurate census of the fish population. Clearly, in the
cases of fish and fauna there is a wide margin for error.
Therefore a quantitative and qualitative accounting
method has been adopted to measure natural capital. The
qualitative aspect is based on the Initial Environmental
Analysis (IEA), which was carried out during the
implementation stage of the Environmental Management
System (EMS) [4]. During the analysis care was taken to
indicate any sensitive species, whether of community or
priority interest. As regards the qualitative aspect
reference was made to the results of a visual census2.
B. Natural flow account
In order to construct a natural flow account for the
MNMR flows of energy and matter that move from the
technosphere to the biosphere and vice versa needed to
be traced. Moreover, input/output matrixes would be
required to reconstruct these movements [5], [6]. In order
to allocate monetary value to natural flow a cost-benefit
approach has to be adopted.
In this case costs are:
• monetary (costs contained in the profit and loss
account),
• environmental (flows between the technosphere and
the biosphere),
and benefits are:
• monetary (revenues contained in the profit and loss
account),
• environmental (flows between biosphere the and the
technosphere).
Two conditions are required to complete the framework:
1. the same unit of measure must be used in all the
accounts, namely a monetary unit;
2. the cost and revenue items must also be the same for
both the income statement and the environmental
account, as is the case for the input/output matrix
used in the national environmental account.
1) Technosphere-Biosphere flows
a)
from Nebbia’s analysis of the input/output matrix [1]. He
found that the national accounting breaks down human
activity into technosphere sectors. The environmental
accounting for a protected area divides human activity
according to management goals. It is by means of these
goals that the administrative body achieves the reserve’s
objectives. There are a total of six goals [4]:
• A: protection of the environment and exploitation of
natural resources;
• B: promotion and dissemination of marine
environment knowledge;
• C: environmental education;
• D: scientific research;
• E: the promotion of sustainable development;
• F: financing overheads and one-off costs.
Each of these goals benefits from a flow of energy and
matter from the biosphere. The IEA was used to identify
the flows [4]. Indeed EC Regulation n. 761/2001 (Emas
2) provides for the fact that the objective of the IEA is to
identify significant environmental interaction and to
evaluate the degree of environmental impact caused by
this interaction. Impact is related to the following factors:
• anthropic presence (knowledge regarding the marine
environment and its management, promotion of
environmentally-friendly business activity);
• raw materials use (upkeep residuals, urban waste);
• consumption of fuel for motor vehicles;
• consumption of heating fuel;
• consumption of electricity;
• water consumption;
• administration expenses.
Environmental impacts are linked to the consumption of
matter and energy, or the return of used resources. In
order to transform these impacts into environmental
costs, the IEA consumption accounting method was used
[4]. An estimate of the environmental cost for various
consumption items is achieved by using equivalent
tonnes of CO2 as the unit of measurement and estimating
the external cost per kilogram of CO2 to obtain a
monetary value. The next step is to apply the
environmental costs, which have been measured in
monetary terms, to the six goals that make up sections of
the MNMR technosphere.
b)
Monetary costs
After classifying environmental costs we moved on to the
reclassification of the costs taken from the 2004 income
statement of 31.12.2004. To do this we used the Long
Term Financial Plan approach3 [7]. This meant that all
the cost items on the reserve’s income statement were
reclassified according to the six Ministry of Environment
goals.
Environmental costs
The method used to classify environmental costs derives
2
A visual census is a non-invasive technique used to monitor fish
species by means of observers provided with boards or underwater
cameras.
3
The Long Term Financial Plan was presented by the Conservation
Finance Alliance together with The Nature Conservancy at the 5th
World Parks Congress, which was held in Durban (South Africa) in
September 2003. The LTFP is a long-term model for finance plan
management regarding parks and protected areas. The cost items are
recorded for management plans and sub-plans and cost centres.
TABLE II: ESTIMATE FUNCTIONS
Suggested by
Suggested by MNMR biologists
Costanza et al. [9]
Gas regulation
Nutrient cycle
Biological control
Habitat/refugia
Food production
Raw materials
GAS REGULATION
NUTRIENT CYCLE
FOOD PRODUCTION
BIOLOGICAL CONTROL
HABITAT/REFUGIA
RAW MATERIALS
RECREATION
CULTURAL
CONSERV.& EXPLOIT.
DISSEMINATION
EDUCATION
RESEARCH
SUST. DEVELOPMENT
MANAGEMENT
MANAGEMENT
SUST. DEVELOPMENT
RESEARCH
EDUCATION
DISSEMINATION
CULTURAL
RECREATION
RAW MATERIALS
HABITAT/REFUGIA
BIOLOGICAL CONTROL
FOOD PRODUCTION
CONSERV.& EXPLOIT.
MANAGEMENT
GOALS
ENVIRONMETNAL
FUNCTIONS
NUTRIENT CYCLE
The input/output matrix describing the relationship
between the biosphere and the technosphere divides the
biosphere up into natural inorganic entities (air, water
and soil) and types of living organisms (producers,
consumers and decomposers). However, since the reserve
only covers an area of 121 ha. this subdivision might not
have suited the research aims, and so we decided to
substitute it with an ecosystem approach based on
subdivision according to function.
In the last few decades there has been an increasing
interest in the valuation of ecosystem functions and
environmental goods and services [8]-[16]. De Groot’s
specification [11] regarding ecosystem functions, which
was taken up by Costanza et al. [9], should be interpreted
as the ability of natural processes and components to
provide goods and services that meet human needs both
directly and indirectly.
GAS REGULATION
Environmental benefits
ENVIRONMETNAL
FUNCTIONS
a)
an estimate of the monetary value of the
reserve’s environmental impact (based on the
IEA),
o a reclassification of costs on the basis of the
LTFP model.
By using a single unit of measurement (monetary) and a
sole classification we were able to unify three separate
instruments: the IEA, the LTFP and the environmental
accounting.
o
MANAGEMENT
GOALS
2) Biosphere-technosphere flows
Figure 2: Natural flows account for the MNMR..
Recreation
IV. ANALYSIS
Cultural
The continental shelf is the main feature of the MNMR’s
marine ecosystem, and is the basis for the functions that
Costanza et al. [9] identified in Table II. The following
functions are estimated: nutrient cycle, biological control,
food production, recreation, and culture (the value of
scientific and educational capital). Some of the functions
were proposed by MNMR biologists. However, due to
insufficient data this initial analysis has not considered
the functions of gas regulation and habitat/refugia.
Moreover, given the small surface area we did not
believe that it would be appropriate to estimate raw
materials production.
b)
Monetary benefits
Having defined technosphere sectors and biosphere
categories it is now possible to construct the biospheretechnosphere input/output matrix for the MNMR as
illustrated in Figure 2. The matrix summarises the
model’s structure and the approach outlined in the
previous sections, which can be encapsulated in the
following points:
• the monetary value of biosphere/technosphere flows
are estimated by means of:
o an estimate of the monetary value of the
reserve’s functions,
o a reclassification of income;
• the monetary value of technosphere/biosphere flows
are estimated by means of:
A. Estimate of environmental and monetary benefits
for the MNMR
The gas regulation function carried out by the MNMR
ecosystems has not been estimated in monetary terms
because, since this was the first application of our
accounting model, the data were not available. From a
methodological point of view, the estimate should have
measured the carbon content stored during the formation
of marine sediment due to the work of bivalves, as well
as the regulation function carried out by seaweed strata.
The nutrient cycle function considers the average
concentrations
of
phosphorous
and
nitrogen.
Replacement cost is used to estimate the value of this
function, i.e. the cost of removing phosphorous and
nitrogen mechanically. In the last 15 years there has been
an increase in the concentration of these elements in the
MNMR. This supports the hypothesis that marine
ecosystems store production residuals deriving from
outside the area. Replacement costs for continental
shelves vary between $752/ha. and $2,110/ha. per year
[9]. By taking a precautionary stance (the lowest figure),
and applying suitable inflation and dollar-euro exchange
rates, a value of €773.86/ha. per year is reached. Since
the MNMR covers an area of 121ha., the annual value of
its contribution to the nutrient cycle can be estimated as
€93,636.88.
Food production takes both fishing and angling into
consideration. It has been estimated that professional
fishermen catch 630,000 kg of fish per year from within
the vicinity of the MNMR [4], [17]. By multiplying the
total weight of the fish by their market value we can
obtain an estimate of the monetary value of the food
production function. The value of red meat fish (sardines,
mackerel, etc.) is not included because these species are
only present in the area due to sea currents. Moreover, as
it is difficult to accurately locate the positions of fishing
boats only 50% of the catch is allocated to the reserve.
On the contrary, as far as the anglers who fish close to
the reserve are concerned the total catch is allocated to
the area. An overall estimate of the food production
function amounts to €84,025.50.
As far as the biological control function is concerned,
Costanza et al. [9] assume that control exerted by the
high trophic levels is at least 30% of the fish catch value.
Consequently, if we take the food production estimate
mentioned above we will obtain a figure of €25,207.65
for the biological control function.
As regards the habitat/refugia function, the widespread
presence inside the reserve of 13 fish/fauna species has
been monitored (out of 116 recorded in the Adriatic and
Mediterranean Seas) [18], as well as 3 species found in
confined areas (Pleuronectidae, Syngnathidae e
Blenniidae). Most probably the reserve acts as a
recruitment area, since a large quantity of small creatures
can be found just after the reproduction period. In order
to produce a monetary value for the habitat/refugia
function it would be necessary to calculate the
reproduction rate or the annual increase in the most
commercially valuable fish species. In this way a
corresponding value can be given to a portion of the food
production function. However, it has not yet been
possible to estimate reproduction rates inside the MNMR.
Because of the reserve’s size and characteristics an
estimate of the raw materials function is not feasible.
Tourism in the MNMR has been divided into two
categories: recreation and culture. The former regards
free-time activities, while the latter is more closely
related to learning and education and refers to the cultural
function mentioned in Costanza et al. [9]. Three
categories of consumers of recreational activity have
been analysed: visitors to the visitors’ centre, and people
taking part in underwater activities: scuba divers and
snorkellers. Contingent valuation methods have been
used to give a monetary value to the benefits deriving
from each of the recreational activities. This results in
estimating the recreational demand function from which
the so-called consumer surplus can be derived, i.e. the
value that the consumer assigns to the services offered by
the reserve extra to the price of the entrance fee. An
estimate of the surplus is obtained by estimating the
demand function. This can be achieved by linking the
number of visitors (quantity) to the variable dimension of
tickets (price). The overall benefit is obtained by adding
surplus and price. A surplus figure of €22,250.16 has
been estimated for the visitors’ centre and figures
between €6,962.94 and €15,140.20 have been reached for
each the underwater activities. The price, which derives
from total entrance income, is €29,849.50 (10,301
visitors) for the visitors’ centre, €19, 256 (899 divers) for
scuba diving, and €15,592.50 (1,583 enthusiasts) for
snorkeling.
Moreover, the economic effects of tourism can be
defined as direct, indirect or induced. Direct effects
derive from tourist spending (added value), whereas
indirect and induced effects are tourism’s contribution to
the creation of income. They are estimated by
multiplying the added value by a Leontiev multiplier of
1.54 [19]. Therefore, it is necessary to estimate daily
tourist spending according to spending type and flow
categories (accommodation, catering and publications).
The following data have been gathered through our
questionnaires: accommodation spending €4,065.52;
catering €103,299.50; merchandising and publications
€5,180.38. By applying an income activation parameter,
an overall figure of €173,319.91 has been obtained for
revenues produced directly and indirectly in the MNMR.
By adding the benefit (incomes plus surplus) the
function’s value reaches a figure of €267,231.01. As
regards the natural flow account, which includes income
and expenditure from the income statement, revenues
have been subtracted, leaving a final amount of
€202,533.01.
The cultural function has been divided into two macro
areas: science and education. The former regards the
reserve as a kind of field laboratory, and a quantitative
and qualitative analysis of the function can be achieved
by using the following indicators: number of researchers
based on man-days (from which a monetary value can be
obtained); research projects (project budget); agreements
with Universities and Scientific Institutes for research
and conferences. However, these data are not yet
available and therefore estimates are based on data
deriving from literature [9]. In this case the average value
per hectare per year is €29.84, giving a total of
€3,610.64. The second macro area includes educational
activity that took place in 2004. Two hundred and fifteen
schools organised visits to the MNMR for a total of 4,300
pupils. From accounting data it was calculated that
educational activity produced revenues of €30,583.71 in
2004. Therefore, the overall cultural function value
amounts to €34,194.35 (Table III). Table III also gives
the grand total of €1,280,011.97 for monetary and
environmental benefits.
TABLE III: ENVIRONMENTAL BENEFITS PER FUNCTION
AND MONETARY BENEFITS
Functions
Environmental
benefits
Monetary benefits
Gas regulation
Nutrient cycle
Food production
Biological control
Habitat/refugia
Raw materials
Recreational
Cultural
Revenues
Public funding
Total benefits
Benefits
€
Not available
93,636.88
84,025.50
25,207.65
Not available
Not estimated
202,533.01
34,194.35
64,698.00
775,716.58
1,280,011.97
B. Estimate of the environmental and monetary costs
for the MNMR
Firstly, the anthropic impact on the MNMR was
considered. Tourism generates several consumer
externalities, among which the use of motor vehicles to
reach the area, and the use of complementary and
accessory materials for carrying out recreational
activities. Factors related to anthropic presence
(transport, consumer durables, consumer non-durables,
etc.) contribute to the production of carbon dioxide.
Although the unit of measure is different, the logic
behind the transformation of human presence into carbon
dioxide emissions is the same as the logic and method
behind the approach used to calculate the ecological
footprint [20], [21]. Indeed, whereas in the case of the
ecological footprint total consumption is converted into
equivalent surface area measured in hectares, here the
equivalent unit of measure is kilograms of CO2. By using
a CO2 production coefficient of 6.41 tonnes per
inhabitant per year, and considering that on average a trip
to the MNMR will last half a day, we can calculate that
17,083 visits will translate into 8,541 inhabitant days
giving a total of 149,887.7 kg of CO2. As the cost per
kilogram of CO2 emitted is on average 3.099 eurocents4,
an estimated monetary value of €4,645.50 can be
allocated to the consumer externalities produced by
visitors to the reserve. As regards the allocation of CO2
production to the six goals, anthropic presence was
weighted for each of the following activities:
environmental education through educational activities
and submarine visits (C) €4,645.50; promotion of
sustainable development by means of fish-tourism (E)
€3,889.25.
As concerns raw materials use, data supplied by the
reserve for paper consumption in 2004 were converted
into equivalent CO2 quantities, which amounted to
€13.62. Despite the fact that paper consumption is
common to all the goals, the figure was so low that it was
allocated exclusively to overheads goal (F). The fuel
consumed in the MNMR is used both for motor vehicles
and heating. Consumption for 2004 converted into
equivalent CO2 emissions translated into an
environmental cost of €215.95. Since the consumption of
fuel for motor vehicles is common to all the goals except
for goal A (as stated in the IEA), the total was shared
equally among all the other five goals (€35.99). LPG is
used in the reserve for heating, which emits CO2 during
combustion. From the Apat (Environmental Protection
Agency) [23] it can be deduced that a kilogram of LPG
will produce an equivalent of 3.02 kg of CO2. However,
by adding together emissions of CH4 and N2O total CO2
amounts to 3.16 kg/kg of fuel. Therefore, consumption
for 2004 translated into CO2 emissions is equal to
€387.80. Given that, according to the IEA, the
consumption of heating fuel falls entirely within goal F,
the complete sum can be allocated to the reserve’s
overheads.
Electricity consumption was 54.42kWh, which translates
into an environmental cost of €1.19. The IEA states that
this figure should be shared equally among all the goals,
4
Monetary valuation allows us to measure the environmental and
social impact of energy production. However, the estimates are still
inaccurate. The highly complex methodology only considers a limited
number of impacts related to energy production. These initial estimates
are based on a method devised for the ExternE EU project [22].
but the figure was so low that it was allocated solely to
goal F.
Annual water consumption amounted to 273.39m³, which
was equivalent to an environmental cost of €3.07. Again,
despite the fact that according to the IEA this figure
should have been shared equally among goals B, C and
F, it was so low that it was assigned solely to goal F.
Table IV illustrates environmental costs for all the six
MNMR management goals.
TABLE IV: ENVIRONMENTAL COSTS ALLOCATED
TO MANAGEMENT GOALS
Motor Heating Electricity Water
Raw
Goals Anthropic
presence materials vehicle
fuel
fuel
€
€
€
€
€
€
A
35,99
B
35,99
C
4.645,50
35,99
D
35,99
E
3.889,25
35,99
F
13,62
36,00
387,8
1,19
3,07
Costs
8.534,75
13,62 215,95
387,8
1,19
3,07
In order to conclude the cost analysis, the income
statement costs have to be added to the environmental
costs. The 2004 income statement was reclassified
according to the LTFP model. In this way the totals could
be allocated to the MNMR management goals (Table V).
TABLE V: MONETARY COSTS ALLOCATED TO MANAGEMENT GOALS
Sums allocated
Goals
€ 10.680,00
A) Protection and exploitation
€ 65.715,25
B) Promotion and dissemination
€ 214.165,56
C) Environmental education
€ 23.620,89
D) Scientific research
€ 203.645,55
E) Sustainable development
€ 81.853,35
F) One-off costs
€ 219.526,24
F) Overheads
Total amount allocated
€ 819.206,84
Now it is possible to obtain a figure for the net benefit in
2004, limited to flows from the biosphere to the
technosphere and vice versa. By subtracting costs from
benefits, both monetary and environmental (the
difference between the totals in Tables III and V), we can
see that the MNMR produced an annual net benefit of
€460,805.13.
V. DISCUSSION
In consideration of the three limitations mentioned earlier
(scale, physical measure unit and environmental costs) an
accounting model was proposed that would take into
account how much the reserve produced, and that would
be capable of co-ordinating and amalgamating various
instruments: LTFP (through the reclassification of costs
and income), IEA (monetary valuation of environmental
costs) and Costanza’s model for ecosystem valuation
(monetary valuation of environmental benefits).
From an analytical viewpoint the environmental balance
for the MNMR was positive to the sum of approximately
€461,000. How can this result be interpreted? Generally
speaking, it can be said that the reserve’s development
model is in line with sustainability. If this were not so,
the balance would be negative. Therefore, natural capital
policies fully achieve objectives regarding sustainable
development, protection and exploitation. If we compare
the net benefit figure of €460,805.13 with the financial
analysis contained in the LFTP and with the €735,000
contributed by the Ministry of Environment and the
Regional Council, we can conclude that 64% of public
funding is covered by the net benefits produced by the
reserve. It is as if public bodies contributed a net figure
of approximately €274,000.
Finally, we feel that more research should be done in
order to investigate the difficulties (incomplete
assessment procedures and insufficient data) connected
with the implementation of the model.
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