Integrating Environmental Accounting, Life Cycle and Ecosystem Services Assessment

Silvio Viglia, Andrzej Nienartowicz, Mieczys?aw Kunz, Pier Paolo Franzese

1Department of Science and Technology, Parthenope University of Naples, Italy

2Faculty of Biology and Environment Protection, Nicolaus Copernicus University, Toruń, Poland

3Faculty of Earth Sciences, Nicolaus Copernicus University, Toruń, Poland

4Industrial Ecology Programme, Department of Energy and Process Engineering, Norwegian University of Science and Technology, Trondheim, Norway

Integrating Environmental Accounting, Life Cycle and Ecosystem Services Assessment

Silvio Viglia1, Andrzej Nienartowicz2, Mieczys?aw Kunz3, Pier Paolo Franzese4?

1Department of Science and Technology, Parthenope University of Naples, Italy

2Faculty of Biology and Environment Protection, Nicolaus Copernicus University, Toruń, Poland

3Faculty of Earth Sciences, Nicolaus Copernicus University, Toruń, Poland

4Industrial Ecology Programme, Department of Energy and Process Engineering, Norwegian University of Science and Technology, Trondheim, Norway

Submission Info

Communicated by Sergio Ulgiati

Forest Ecosystem Services

Environmental Accounting

LCA

Multicriteria

Bory Tucholskie National Park

Environmental protection is often considered as competing with human activities and economic development. On the contrary, more innovative guidelines recommend nature conservation to be achieved without banning human activities but, instead, developing appropriate management practices aimed at joint economic, social, and environmental sustainability. The suitability of such management schemes should be evaluated through integrated assessment frameworks overcoming mono-dimensional metrics and criteria. In this study, we integrated different environmental accounting methods with life cycle and ecosystem services assessment to investigate the interplay of human activities and nature conservation in the Bory Tucholskie National Park (Poland). Indicators of environmental costs and impacts due to the exploitation of forest ecosystem services in the study area were calculated. In addition, the economic and ecological value of the main forest ecosystem services was assessed to explore the benefits gained in preserving stocks of natural capital while exploiting flows of ecosystem services.

? 2013 L&H Scientific Publishing, LLC. All rights reserved.

1 Introduction

Forest ecosystems provide not only food, fibers, chemicals, and construction materials, but also biomass as an alternative energy source as well as services of climate regulation, water cycle and uptake of emis-sions, not to talk of biodiversity protection [1,2]. Therefore, forest ecosystems have always, directly and indirectly, supported human life playing an important role for human well-being [3-5].

Some forests (especially in tropical areas) are undergoing a significant overexploitation due to human activities while several boreal forests show a growing stock since the 1950s, after centuries of stock decline and deforestation [6,7]. When forests are gradually converted into cropped area and pasture, the services they provide decline. Such a degradation of ecosystem services should be considered as a loss of capital asset. Yet, conventional accounting systems do not include measures of resource depletion or ecosystem service degradation [8]. As a consequence, severe forest exploitation would only show a positive increment of the GDP despite the loss of natural capital [9].

The 1992 U.N. Forest Principles identified the multifunctional and multiservice purpose of the world’s forests as follows: ‘‘Forest resources and forest lands shall be managed and used sustainably to fulfill social, economic, ecological, cultural and spiritual needs of present and future generations’’. There are different types of services provided by forests and woodlands. According to the Millennium Ecosystem Assessment [9], they can be divided in: 1) provisioning, 2) regulating, 3) cultural, and 4) supporting services. Examples of ecosystem services from forest are: timber, fuel wood, water protection and regulation, soil and biodiversity protection, ecotourism and recreative activities, cultural and spiritual values, among others [1,10,11].

The whole human economy is sustained by stocks of natural capital and flows of ecosystem services, without which only the economic capital and human labor could not ensure human well-being. Disregarding the biophysical constrains to human economy in the long run can result into an extreme impoverishment of natural resources and severe problems of environmental degradation [12]. Concerns about the size and impact of human economy at global scale in relation to “planetary boundaries” and a possible definition of a “safe operating space for humanity” have been discussed by Rockstr?m et al. [13].

In this framework, a key role can be played by integrated assessment frameworks capable of assessing the environmental performance and sustainability of human-dominated ecosystems and processes investigated at different scales under a life cycle assessment perspective [14-19].

Several authors have investigated the interplay between forest ecosystems and human activities by using different approaches, such as the Life Cycle Assessment [20,21], the Emergy Synthesis method [22], the economic valuation [4,23,24], the multicriteria analysis [25,26], and other integrated approaches to environmental accounting [27].

In this study, we implemented a multicriteria assessment framework integrating different environmental accounting methods with life cycle and ecosystem services assessment to investigate the interplay of human activities and nature conservation in the Bory Tucholskie National Park (Poland). The main goal of the assessment was the calculation of a set of indicators describing environmental costs and impacts due to the exploitation of forest ecosystem services. In addition, the economic and ecological value of the main forest ecosystem services was also assessed to explore the benefits gained in preserving stocks of natural capital while exploiting flows of ecosystem services.

2 Materials and Methods

2.1 The area of study

The Bory Tucholskie National Park (Fig. 1), located in northern Poland, was founded in 1996. Since 2010, this national Park is included within the UNESCO-MAB Tuchola Forest Biosphere Reserve, of which it represents the main core area [28]. The National Park represents the most valuable natural area of the whole Tuchola Forest region. It covers an area of 4,613 ha and it is classified as biome n. 5 (forests of the temperate zone, forests of Central Europe) according to the biogeographical classification of the world [29]. The Park comprises more than twenty lakes with a total water surface of 530 ha and almost 4,000 ha of forest land: 11.5% and 85.3% of the total area of the Park, respectively. Despite the low diversity of the tree species (97% of the standing wood biomass is represented by Pinus sylvestris [30], the Park is home to 173 species of vertebrate (20 species of fishes, 11 species of amphibians, 5 species of reptiles, 100 species of birds, and 37 species of mammals) of which 119 are protected.

(http://www.park.borytucholskie.info/index.php?a=56).

In the past, the vegetation cover was highly influenced by human activity because the area was mainly dominated by forestry. Nowadays, in the Park, and more in general in the whole Tuchola Forest, new management schemes more in line with ecological principles and use of natural methods of forest breeding are adopted, thus taking into consideration the need for protection of different existing forest ecosystems. As the conservation and restoration of natural habitats are the main goals of the Bory Tucholskie National Park, many activities are forbidden and others are permitted under restriction.

Ecosystem services connected to human activities in the Park area that are also relevant from an economic point of view are: 1) fishery and hunting products, 2) forestry products, 3) agricultural products, and 4) tourism and educational activities.

Fig.1 Bory Tucholskie National Park, Poland.

2.2 The multicriteria assessment framework

The performance of human activities carried out in a forest national Park can be evaluated in many different ways using economic, social, and environmental assessment methods and perspectives. In this study, we integrated different environmental accounting methods with life cycle and ecosystem services assessment to provide a large set of intensive and extensive indicators referring to multiple scales and dimensions. Extensive indicators account for total (direct and indirect) flows of environmental resources supporting the investigated Park system, also including hidden flows occurring at larger spatial and time scales. Extensive indicators are related to the physical size of the system while intensive indicators are relatively independent on the physical size of the system and provide a measure of environmental performance in relation to generated products [27].

The environmental accounting methods used in this study can be divided in two broad categories: (1) upstream methods (material flow accounting, embodied energy analysis, emergy accounting), focusing on the cumulative amount of environmental resources used per unit of generated product, and (2) downstream methods (CML2 baseline 2000), more concerned with the consequences of the system’s emissions.

While the upstream methods were used to calculate cumulative performance indicators capable of accounting for the depletion of environmental resources, the downstream method looked at the contribution to environmental impact categories due to the exploitation of ecosystem services.

The integration with the emergy method added up to the multidimensionality of the assessment by also including in the accounting free environmental resources as well as direct human labor and economic services. In so doing, the emergy method provided an ecological donor-side value of the ecosystems services exploited in the Park in terms of the cumulative work done by the biosphere to generate them.

Finally, an economic analysis of direct costs and benefits complemented the more ecological information generated by the emergy accounting with a user-side perspective on the economic value of the exploited ecosystem services. The economic profitability of the Park was assessed by calculating the market value of the provisioning and cultural services. In addition, an average economic value of the regulating services was also estimated in order to compare the total economic value of the exploited ecosystem services with the annual investment by the local and national government.

2.3 The material flow accounting

The Material Flow Accounting [31-33] aims at evaluating the environmental disturbance associated with the withdrawal or diversion of material flows from their natural ecosystemic pathways. In this method, appropriate Material Intensity factors (g/unit) are multiplied by each input to the system, accounting for the total amount of biotic and abiotic matter, water, and air that is directly or indirectly required to provide that very same input to the system. The resulting Material Intensities (MIs) of each input are then separately summed together for each environmental compartment (biotic and abiotic matter, water, air), and assigned to the system’s output as a quantitative measure of its cumulative environmental burden from that compartment (often referred to as “Ecological Rucksack”).

2.4 The embodied energy analysis

The Embodied Energy Analysis [34,35] aims at evaluating the gross energy requirement of the system in terms of direct and indirect consumption of fossil energy (sometimes also referred to as commercial energy) to produce a good or service. In this method, all the material and energy inputs to the investigated system are multiplied by appropriate oil equivalent factors (g/unit), and the cumulative embodied energy requirement of the system’s output is then computed as the sum of the individual oil equivalents of the inputs. Oil equivalents can be converted to energy units by multiplying them by the conventional calorific value of 1 g of raw oil (41,860 J/g).

Quantifying the total fossil energy invested into a process allows an estimate of the total amount of primary energy used and, as a consequence, the extent of the depletion of non-renewable energy resources caused by the process.

Resources provided for free by the environment (without requiring any consumption of fossil energy to make them available to the process) as well as human labor and economic services are not accounted for when the main focus of the analysis is on the consumption of fossil resources [36].

2.5 The emergy synthesis method

The emergy synthesis method [37,38] looks at the environmental performance of the system on the global scale of biosphere, also taking into account free environmental inputs such as solar radiation, wind energy, rain, geothermal flow, soil erosion, as well as the indirect environmental support embodied in human labour and economic services, which usually are not included in conventional energy analyses. Moreover, through the emergy method the accounting is extended back in time including the environmental workneeded for resource formation. All inputs are accounted for in terms of their solar emergy, defined as the total amount of solar available energy directly or indirectly required to make a given product or to support a given flow, and measured in solar equivalent joules (seJ) [38]. The amount of emergy required per unit product is referred to as its specific emergy (seJ/g) or solar transformity (seJ/J), and can be considered a“quality” factor providing a measure of the intensity of the support provided by the biosphere to the process per unit of generated product. The total emergy (U) supporting a process represents an indicator of the total environmental support provided by the biosphere to that process. A comprehensive description of the emergy theory, accounting methodology, and indicators can be found in Brown and Ulgiati [39,40].

2.6 The CML2 baseline 2000

Downstream impacts are associated with airborne and waterborne emissions and solid wastes. The assessment of these impacts can be performed in two different ways: (1) mid-point assessment, calculating the amount of emissions and assigning them to specific impact categories (i.e., damage potential), under the assumption that “l(fā)ess” is better; (2) end-point assessment, quantifying the extent to which a damage actually or potentially occurs (e.g., fraction of affected species; overall disease or disability generated, expressed as the number of years lost due to ill-health, disability or early death).

In this study, we used the CML2 baseline 2000 method (http://www.leidenuniv.nl) aimed at evaluating the potential environmental damage of airborne, liquid, and solid emissions by appropriate equivalence factors to selected reference compounds for each impact category. The potential impact of the investigated processes for each category was calculated by multiplying all the emissions by their respective impact equivalence factors.

The impact categories selected in this study are: 1) global warming potential, human toxicity, photochemical oxidation, acidification, and eutrophication.

2.7 Basic data, assumption, and allocation procedures

Based on a systems diagram of the study area (Fig. 2), tables of the input and output flows of the Park system were implemented. Basic raw data referred to the year 2010 were provided by the Authority of the Bory Tucholskie National Park. Raw data were used to account for the matter, energy, and money flows supporting the National Park in the time frame of one year. However, due to lack of disaggregated data for the different activities performed in the Park, we assumed that all input flows were used to generate the outputs. In addition, to calculate energy, material, and emissions intensity factors, the rules of Life Cycle Assessment (ISO 14040/44 [41,42]) were adopted, allocating the total input resources according to the economic value of the generated products (forestry, fishery, hunting, and agricultural products) and services (tourist and educational activities). Environmental costs of outputs were calculated by dividing the allocated amounts of invested inputs by the money value of the different types of product or service. Instead, for the Emergy Synthesis method the emergy algebra was applied (i.e., no allocation of input flows to products), under the assumption that all input flows were needed to generate all the outputs.

3 Results and Discussion

The systems diagram of the Bory Tucholskie National Park drawn by using Odum’s energy systems language is shown in Fig. 2. The natural ecosystem, shown in the left part of the diagram, is directly supported by renewable resources. The renewable flows (sun, rain, wind, geothermal), aggregated on the left of the diagram, directly support the natural ecosystem, also providing indirect support to human activities. In addition to renewable flows, several human-driven flows imported from the human economy (fossil fuels, electricity, goods, machinery, and labor) support the production patterns of the Park. These flows are shown as inflowing from the top of the diagram. Tourists visiting the Bory Tucholskie National Park interact with local assets and productive activities, enjoying local products, environmental and recreation services. Then, they leave the Park most probably enriched with a deeper understanding of the environmental, economic, and social aspects of the area, also thanks to the activity of environmental education.

Fig. 2 Systems diagram of the Bory Tucholskie National Park, Poland.

The economic budget of the Park is composed by income related to production activities (exported goods) and mainly by the contributions from local and central government. Tourists also provide an additional income used to import goods (equipment, machineries, etc.) and energy from outside the system. Money flows, drawn as dotted lines in Fig. 2, are shown as entering from the right side of the diagram and flowing out as payments for services associated to imports. It is important to note that the money paid for resources import only refers to the services associated to such resources. Services measure the indirect labor invested outside of the investigated system to extract and process the raw materials and make processed resources available to the production process (money is not paid to nature for its free resources but it is always paid to support direct and indirect labor).

The main indicators calculated by implementing the Embodied Energy Analysis and Material Flow Accounting are summarized in Table 1 and 2. Indicators were calculated for the exploitation of three main provisioning ecosystem services (fishery and hunting, forestry, and agriculture) and for cultural ecosystem services (tourist and educational activities). All results referred to the human exploitation of the provisioning ecosystem services were calculated per unit of product (gram of dry matter or joule of energy content). Instead, for tourist and educational activities, results are given per number of days of presence.

To support the production of 1 g of fishery and hunting products, 1 g of wood biomass, and 1 g of forage in the study area required 1.10, 0.02, and 0.15 g of oil equivalent, respectively (Table 1). Each visit to the Park required 37.69 g of oil equivalent per person per day whereas the total annual energy demand of the Park was 3.60×107g oil eq., equivalent to 1.50×1012J (Table 1).

Table 1 Fossil energy resource depletion

The results in Table 1 and 2 show that the request of energy, abiotic material, and water is higher for fishery and hunting products when looking at the intensity factors (intensive indicators) while the forestry sector showed the greatest figures when considering the size of the different production sectors (extensive indicators). This is due to the greater size of forestry activity compared to the minor sectors of fishery and hunting, and agriculture. The implementation of educational and tourism activities required about 40 g of oil equivalent, 200 g of abiotic material, and more than 2 liter of water per visitor per day. The cumulative abiotic material demand of the Park was 1.87×108g/yr whereas the total water demand was 2.12×109g/yr (Table 2).

The emergy value of the local renewable inputs (R) was 3.07×1018seJ/yr whereas the net primary production (NPP) was 1.18×1010g d.m./yr (Table 3). The ratios between R and the annual NPP of the Park, the CO2annually sequestered, the amount of water cycled through evapotranspiration, and the total O2released, allowed the calculation of the emergy intensity factors of these supporting and regulating ecosystem services (Table 3). These values of specific emergy provide an estimate of the ecological value of the selected ecosystem services in terms of the work done by the biosphere to support their generation.

The calculated specific emergy value of the NPP was then used to estimate the emergy value of the standing vegetal biomass in the Park (5.24×1011g of stored organic matter), resulting in 1.16×1020seJ (Table 4), a measure of the natural capital in terms of biomass.

Other natural capital storages are also of interest under the perspective of nature conservation: the surface water and the soil organic matter. The stocks of surface water and soil organic matter were estimated in 4.16×1013g and 3.69×1011g (http://soils.usda.gov/). These storages of natural capital were converted to emergy units by means of their specific emergy values, resulting in 9.44×1018and 2.30×1021seJ (Table 4).

The total renewable emergy flow of 3.07×1018seJ/yr (Table 3) can be considered as a measure of the work of biosphere to provide ecosystem services (water cycle, biomass supply, topsoil turnover, etc). Instead, the total emergy stored in natural capital, accounting for 2.42×1021seJ (Table 4), provides a measure of the “size” of the system in terms of cumulative biosphere work over time.

The histogram in Fig. 3, sometimes referred to as “emergy signature”, shows the relative importance of the main driving forces supporting the metabolism of the National Park. The main driving forces are represented by Services (S), Labor (L) and Renewable emergy flows (R).

Table 2 Abiotic material and water resource depletion

Table 3 Emergy value of renewable inputs and selected ecosystem services

Table 4 Emergy values of selected stocks of natural capital

Fig. 3 Main driving forces supporting the Bory Tucholskie National Park, Poland.

In Table 5, intensive (i.e., calculated per unit product) and extensive (i.e., calculated for the whole area) emergy-based indicators summarize the results of the emergy accounting method. The total emergy input of the Park (U) - namely what is invested by nature to support it and what is invested by the human economy to manage and exploit it - was 1.06×1019seJ/yr (Table 5). The environmental performance of the main ecosystem services exploited in the Park was evaluated as emergy flow per unit of generated product expressed as mass flow (g), energy content (J), and market value (€). These indicators summarized in Table 5 were calculated with and without accounting for Labor and Services, thus providing results that consider the contribution of human labor and economic services and a pure biophysical accounting.

The Environmental Loading Ratio (ELR) of the Park as a whole, i.e. the total loading of all the activities measured as the amount of the human-driven emergy inputs imported into the system per unit of free environmental emergy input locally available, was 2.46 (Table 5). The Emergy Yield Ratio (EYR), a measure of the ability of a process to exploit the local resources by investing resources from outside, was 1.41 (Table 5). Considering that a wilderness area should have an ELR equal to zero and that the lowest possible value of the EYR is 1.0 by definition, the calculated emergy indicators proved a relatively environmentally sound management of the whole Park system. This result is also confirmed by the value of the Emergy Sustainability Index (ESI) of 0.57 (Table 5).

Table 5 Intensive and extensive emergy-based indicators

Table 6 Contribution to environmental impact categories due to the exploitation of ecosystem services

Table 7 Annual investment from the government and economic value of ecosystem services

Table 6 shows the contribution of the activities performed in the Park to the Global Warming Potential (g of CO2equivalent) and the Acidification Potential (g of SO2equivalent). The calculated emissions were mainly related to the use of fossil fuels (diesel, gasoline) and electricity consumption. Also in this case, the biggest impact resulted associated to the Forestry sector with 8.19×107g CO2eq. and 5.81×105g SO2eq. (Table 6).

Monitoring these environmental costs and impacts over time would allow verifying to what extent the Park management is implementing management schemes oriented to improve the environmental performance of the system. Therefore, the obtained results also represent a useful benchmark for future evaluations and possible comparisons.

The human activities performed in the Bory Tucholskie National Park show an overall good environmental performance even if a problem arises when the focus is placed on the issue of economic selfsufficiency. Most of the economic budget of the National Park relies on the external support from the local and central government accounting for 781,250 €/yr (Table 7). The total market value of the provisioning and cultural ecosystem services in the Park, calculated considering their market price for the specific location and reference year, accounted for 122,668 €/yr (Table 7). This result shows that the annual investment from the government was more than 6 times the economic value of the provisioning and cultural services.

Nevertheless, assessing the benefits of the Park only in terms of direct economic return prevents from a proper understanding of the complexity interconnecting economic development, ecosystem services, and human well-being. In addition, it should be remarked that forest ecosystems do not only provide provisioning and cultural services but also regulating services which are of great importance for human wellbeing.

In general, it is difficult to estimate the economic value of regulating ecosystem services as this value is typically affected by a high uncertainty. In this study, we assessed the overall value of regulating services by multiplying the hectares of forest area in the Park by the average economic value of regulating ecosystem services for temperate forests of 490 $/ha/year [11]. Using this average figure, the economic value of the regulating services of the Park resulted 1,440,000 €/yr (Table 7). By adding the economic value of provisioning, cultural and regulating services, the total economic value of all ecosystem services accounted for 1,562,668 €/yr (Table 7) largely overcoming the annual investment from the government, thus confirming the worth of investing in natural capital conservation and sustainable management options also from an economic viewpoint.

4 Concluding remarks

The trade-off between nature conservation and the exploitation of natural resources is a complex issue that requires multicriteria assessment frameworks capable of integrating different methodologies and perspectives. In this study, the integration of different environmental accounting methods with life cycle and ecosystem services assessment allowed a more comprehensive understanding of the economic and environmental costs and benefits due to human activities in the Bory Tucholskie National Park.

A strong research effort should be applied in this direction to better support local managers and policy makers committed to develop environmental plans and policies for a sustainable management of natural resources. The proposed integrated assessment approach is useful in this framework as it can provide solid scientific information while taking into account ecological, environmental, and economic aspects.

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[37] Odum, H.T. (1988), Self organization, transformity and information,Science, 242, 1132-1139.

[38] Odum, H.T. (1996),Environmental Accounting: Emergy and Environmental Decision Making, John Wiley & Sons, NY.

[39] Brown, M.T. and Ulgiati, S. (2004), Energy quality, emergy, and transformity: H.T. Odum’s contributions to quantifying and understanding systems,Ecological Modelling, 178, 201-213.

[40] Brown, M.T. and Ulgiati, S. (2004), Emergy analysis and Environmental Accounting,Encyclopedia of Energy, 2, 329-354.

[41] ISO 14040 (2006),Environmental Management - Life Cycle Assessment – Principles and Framework, Brussels, 20 pp.

[42] ISO 14044 (2006),Environmental Management - Life Cycle Assessment - Requirements and Guidelines, Brussels, 46 pp.

[43] Odum, H.T.(2000),Handbook of Emergy Evaluation Folio 2: Emergy of Global Processes, Centre for Environmental Policy, University of Florida, Gainesville.

[44] Buenfil, A.A.(2001),Emergy evaluation of water, PhD thesis. University of Florida, Gainesville, Florida (USA).

23 September 2013

?Corresponding author.

E-mail address: pierpaolo.franzese@ntnu.no (Pier Paolo Franzese).

ISSN 2325-6192, eISSN 2325-6206/$- see front materials ? 2013 L&H Scientific Publishing, LLC. All rights reserved.

10.5890/JEAM.2013.11.001

Accepted 1 November 2013

Available online 1 January 2014