This article appeared in a journal published by Elsevier. The attachedcopy is furnished to the author for internal non-commercial researchand education use, including for instruction at the authors institution

and sharing with colleagues.

Other uses, including reproduction and distribution, or selling orlicensing copies, or posting to personal, institutional or third party

websites are prohibited.

In most cases authors are permitted to post their version of thearticle (e.g. in Word or Tex form) to their personal website orinstitutional repository. Authors requiring further information

regarding Elsevier’s archiving and manuscript policies areencouraged to visit:

http://www.elsevier.com/copyright

Author's personal copy

Analysis

Detecting the ‘conservation effect’ on the maintenance of natural capital flow indifferent natural parks

Irene Petrosillo ⁎, Teodoro Semeraro, Giovanni ZurliniLab. of Landscape Ecology, Dept. of Biological and Environmental Sciences and Technologies, Ecotekne, University of Salento, Prov.le Lecce-Monteroni, 73100 Lecce, Italy

a b s t r a c ta r t i c l e i n f o

Article history:Received 4 August 2009Received in revised form 11 December 2009Accepted 22 December 2009Available online 14 January 2010

Keywords:Natural capitalEnvironmental managementConservation policy

The identification of areas worthy of protection and their subsequent institution as natural parks areinstruments that society uses to preserve biodiversity that, by supporting Natural Capital Flow (NCF),represents a guarantee for the maintenance of human life quality. However, the implemented strategies forthe conservation of biodiversity may differ from those adopted for the maintenance of natural capital;consequently, planning for natural capital might require a different strategy from that used in conservationpolicies. The aim of this paper is to assess the ‘conservation effect’ of different conservation policies on themaintenance of NCF in three natural parks in Apulia Region (southern Italy). The assessment of naturalcapital flow variation has been carried out investigating the temporal dynamics of land-use/land-covermosaics, and using Costanza et al.'s economic coefficients as surrogates of NCF. Results showed that not allenvironmental conservation management strategies have played an equal role in fostering NCF. This researchhighlights that the recognition of the natural value of a site according to the European Directives (e.g.NATURA 2000 network) is not sufficiently effective for the conservation of the NCF, while it is necessary toidentify a management authority that can appropriately drive landscape transformations, and sets, ifnecessary, the appropriate limitations. In addition, the management of these areas as part of a network ofnatural parks seems to be more effective for the maintenance of NCF.

© 2009 Elsevier B.V. All rights reserved.

1. Introduction

Recently, society has increased its awareness that natural resourcesare becoming greatly compromised by the overexploitation of biodi-versity, and the factors that limit socio-economic development are nottechnological, but natural, i.e. the quantity of fishery products is notdependent on the numbers and capacity of fishing boats, but on theabundance of thefish population (Daily, 1997). Nevertheless, in the pastdecades biodiversity loss has been so dramatic that it has beenrecognized as crucial in the context of global change (Walker andSteffen, 1996). This has raised several concerns, including the possibilitythat the functioning of Earth's ecosystems may be threatened bybiodiversity loss (Costanza et al., 2007; Ehrlich and Ehrlich, 1981), withimportant effects on ecosystem goods and services and, consequently,on human well-being (de Groot, 2006; Costanza et al., 2007). Inparticular, ecosystem goods (e.g. food) and services (e.g. wasteassimilation) represent the benefits humans derive, directly orindirectly, fromecosystem functions (Costanza et al., 1997; Daily, 1997).

Biodiversity losswould implicate a threat to the survival of mankindfrom both an ecological and a social–economical viewpoint, becausebiodiversity, by supporting ecosystem services, contributes to the

maintenance of the quality of human life. Even though the persistenceof biodiversity and the maintenance of ecosystem services are largelydependent upon each other, these two aspects are not whollyinterchangeable (Williams and Araújo, 2002). While retaining a corefocus on protected areas designated to sustain biodiversity, the newarenas of conservation are much bigger and much more complex thanthe old. They encompass new places dominated by human activity, newrevenue streams from public and private sectors and new goals ofecosystem service provision (Daily and Matson, 2008). Planning forbiodiversity and ecosystem services conservation at the same time andin the same place may be difficult because areas important forecosystem services might not always be important for biodiversity(Balvanera et al., 2001; Chan et al., 2006). For example, the most scenicrivers (cultural service) may not be the ones containing irreplaceablebiodiversity features (Singh, 2002). Therefore, the implementation ofstrategies and tools for the conservation of biodiversity (e.g. landreclamation) may differ from those for the maintenance of ecosystemservices (e.g. resource management); consequently, planning forecosystem services might require different perspectives and strategiesfrom that used in conservation policies (Egoh et al., 2007). For thisreason, often strategies geared to sustaining human well-being likegood production, do not guarantee the maintenance of biodiversity intermsof specific-diversity, butwould foster thepersistence of structuresand functions that support ecosystemservices, bypreserving thenaturaldisturbance regime and the adaptive capacity of the biotic component.

Ecological Economics 69 (2010) 1115–1123

⁎ Corresponding author. Tel.: +39 0832 298896; fax: +39 0832 298626.E-mail address: irene.petrosillo@unisalento.it (I. Petrosillo).

0921-8009/$ – see front matter © 2009 Elsevier B.V. All rights reserved.doi:10.1016/j.ecolecon.2009.12.006

Contents lists available at ScienceDirect

Ecological Economics

j ourna l homepage: www.e lsev ie r.com/ locate /eco lecon

Author's personal copy

The notion of ecosystem services has been introduced as a mean forproviding information on the values humans place on ecosystems andvaluating benefits derived fromnatural resources (Costanza et al., 1997;de Groot et al., 2002; Farber et al., 2002; Abel et al., 2003; Chee, 2004;Groffman et al., 2004; Eamus et al., 2005; Kremen, 2005; MillenniumEcosystem Assessment [MEA], 2005). This is an important step, whichassumes a crucial relevance in the context of biodiversity conservationwhere values are often difficult to quantify in economic terms, andrarely well-explained in natural resource decisions (Wallace, 2007).

Undoubtedly, the concept of ecosystem services is not just asemantic decision, but it is integral to any process seeking to clearlyilluminate trade-offs between natural resource management andpolicy. The full inclusion of ecosystem services concept intoconservation policy would allow for the development of an integratedapproach to evaluating the merits and congruence of differentconservation objectives (Balvanera et al., 2001; Singh, 2002).Furthermore, it would place a specific focus on safeguarding humanwell-being (Balvanera et al., 2001; Kremen and Ostfeld, 2005), whichmight contribute to improve the societal relevance of conservationstrategies (Knight et al., 2006; Egoh et al., 2007).

Since in Petrosillo et al. (2009) we demonstrated that not all theconservation strategies are effective in fostering natural capital flow in aparticular protected area, the aimof this research is to verify if this resultis site-specific or can be generally applicable to other natural parks. Forthis reason, we aim to assess, as a first attempt, the ‘conservation effect’of different conservation policies on the maintenance of natural capitalflow in three natural parks under different conservation regimes.Wherewith ‘conservation effect’ we intend the positive consequences ofsuccessful management strategies to preserve biodiversity and ecosys-tem services, while we use the term natural capital flow to consider thewhole amount of ecosystem services provided by a natural protectedarea. The analysis of natural capital flow variation has been carried outinvestigating the temporal dynamics of land-use/land-cover mosaics,and using the economic coefficients, proposed by Costanza et al. (1997),as surrogates of natural capital.

The paper is organized in the following sections: in Section 1.1 weaddress the concept of natural capital in the context of landscapesciences, in Section 1.2 we focus on the role of natural parks inpreserving natural capital flow. Section 1.3 gives a short description ofthe study area and Section 2 is focused on the Materials and Methodsused. Finally in Section 3 we describe the main results for each naturalpark under study, and in Section 4 and 5 the Discussion andConclusions are reported.

1.1. The Concept of Natural Capital in the Context of Landscape Sciences

The expression ‘European Landscape’ is often used to describe thecontinuous and overall long-term interaction between human activityand natural processes. In the past centuries human activity has shapedand sculpted the landscape with a distinctive touch, altering thenatural disturbance regime (Moloney and Levin, 1996; MillenniumEcosystem Assessment [MEA], 2005) and currently, land-use/landcover transformations are the underlying causes of fragmentation andnatural habitat loss (Alcamo and Bennett, 2003). Globally, it isestimated that 38% of land is in agricultural uses (Food andAgricultural Organization [FAO], 2004), and excluding boreal lands,desert, rock and ice, this amount rises to 50% (Tilman et al., 2001; Daleand Polasky, 2007). Therefore, landscape can be seen as multifunc-tional because it is characterized by various functions and values inspace and time (Haines-Young and Potschin, 2004; Haines-Younget al., 2006; Mander et al., 2007), or rather a complex and adaptivesystem (Levin, 1998) where interaction between ecological patternsand processes, economic-manufacturing processes, and administra-tive political organization of society interact with each other.

Ecosystem Services, seen from a “multifunctional landscape” per-spective, are supported by amosaic of different land cover elements that

can change in quantity (composition) or in their spatial configuration.The combination of output of goods and services provided bymultifunctional landscape can be defined as Natural Capital (Haines-Young, 2000; de Groot, 2006). Natural Capital represents the overallresult of a wide range of processes and interactions through which thenatural and semi-natural components of the landscape support thequality of human life (Costanza et al., 2007). The essence of the concept ofcapital is that it is a stock that shows the capacity of giving rise to flows ofgoods and/or services (Ekins et al., 2003).

Ekins (1992) has disaggregated the capital stock into four differenttypes of capital: manufactured, human, social/organisational andnatural capital. Each of these stocks produces a flow of ‘services’,which serve as inputs into the productive process. Focusing on naturalcapital, it represents a complex category, which performs four distincttypes of environmental functions (Pearce and Turner, 1990), two ofwhich are directly relevant to the production process: the provision ofresources for production (the raw materials that become food, fuels,metals, timber, etc.) and the absorption of wastes from production. Inaddition, there is a third type of environmental function that does notcontribute directly to production, but is the most important because itprovides the basic context within which production is possible (i.e.the basic life-support functions). Finally, the fourth type of environ-mental function contributes to human well-being through what maybe called ‘amenity services’ (Ekins et al., 2003), such as the beauty ofwilderness and other natural areas. Both life-support functions andamenity services are produced directly by natural capital indepen-dently of human activity, but human activity can certainly exerciseadverse effects on them.

In general, the idea of natural capital has been used to explore theinter-relationships between environmental, economic and socialissues, and studies have attempted to integrate traditionally disparatenatural resource, ecological system, aesthetic, recreational andeconomic properties of landscapes (Antrop, 2000; de Groot et al.,2002; Potschin and Haines-Young, 2003; Bailey et al., 2006; Aronsonet al., 2007).

1.2. Natural Parks for the Conservation of NCF

One of the most successful strategies for the conservation of localnatural capital is the establishment of officially and legally recognizedterrestrial and marine protected areas. Both scientific and localcommunities increasingly expect multiple values to be incorporatedwithin planning for conservation (Raymond and Brown, 2006;Cowling et al., 2008; Kumar and Kumar, 2008; Naidoo et al., 2008;Raymond et al., 2009).

Natural protected areas can be considered part of the so-called“critical social–natural resource”, representing natural areas that areof critical value largely as a result of their social value to localcommunities, and bringing people into regular contact with thenatural world (Chiesura and de Groot, 2003). These areas shouldreduce intensive and direct use of ecosystems in terms of frequencyand extraction of resources considering the different requirements ofdifferent stakeholders.

There are different institutional levels wherein the conservationstrategies can apply, in particular at the European level it is possible tohighlight the NATURA 2000 network combining Sites of CommunityImportance (SCIs) designated under the Habitat Directive 92/43 andImportant Bird Areas (IBAs) under the Bird Directive 79/409. At theItalian level, there are mainly the national natural parks (Italian Law394/1991) and regional natural parks. Independently of the kind ofrecognition, these areas are as multifunctional landscapes (Mander etal., 2007), where people and the land are inseparable and areconsidered worthy of protection as such.

The crucial aspect of natural parks is their management, whichpredominantly has been focusing on individual habitats almost in

1116 I. Petrosillo et al. / Ecological Economics 69 (2010) 1115–1123

Author's personal copy

isolation without considering a landscape perspective (Roe and VanEeten, 2001; Brody et al., 2003; Petrosillo et al., 2009).

Policy analysis is a critical element of appraising the effectiveness ofany public policy including nature conservation policy (Papageorgiouand Vogiatzakis, 2006), where managers and policy-makers areincreasingly confronted with the problem of managing the entirelandscape and integrating phenomena across multiple scales of space,time and organizational levels (Berkes and Folke, 1998; Levin, 2006).That claims for new perspectives and insights helping to evaluate theeffectivenessof different kinds ofmanagement and conservationpolicies.

It is fundamental to understand how management of naturalprotected areas influences changes in natural capital and, therefore,human well-being, how they are addressed by conservation policy,which change of natural capital, in terms of level and type, deservesmore attention and is more acceptable, how appropriate standardscan be developed to evaluate and identify institutions and policiesthat can be effective in achieving the desired protection (Daily, 2000).

In this context, a useful tool is represented by retrospectiveanalysis that can help in identifying the possible driving forces ofchange and the main effects of these processes on natural capital. Inaddition, retrospective analysis can facilitate the understanding ofsystem past trajectory that is the basis for tracing future scenarios(Käyhkö and Skånes, 2006). In particular, in order to monitor naturalcapital, retrospective analysis can help in evaluating the effectivenessof different conservation policies on the maintenance of naturalcapital flow (Petrosillo et al., 2009). Since there are important aspectsof natural capital that are not directly measurable and comparable,they need to be derived indirectly through the use of surrogates.Functional to this aim is the use of economic coefficients, introducedby Costanza et al. in 1997, which represent a metric to quantify thebenefits of a variety of goods and services provided by ecosystemsthat do not enter the market. The assessment of natural capitalchanges, resulting from two different kinds of management over timecan be performed, as a first approximation, by estimating andcomparing, in a spatially explicit way, the changes in the economicvalue of natural capital under the current and the past managementregimes (Kreuter et al, 2001; Zhao et al., 2004; Petrosillo et al., 2009).

1.3. Study Area

The study area is represented by three natural parks in the ApuliaRegion (southern Italy) (Fig. 1): “Torre Guaceto”, “Saline Punta dellaContessa” and “Porto Selvaggio e Palude del Capitano”.

Since there are evidences that the conservation management levelcan play an important role in preserving natural capital flow in thesame area (Petrosillo et al., 2009), these areas were selected becausethey are under different conservation regimes, in fact “Torre Guaceto”is a national protected area, “Saline Punta della Contessa” is a regionalprotected area, and “Porto Selvaggio e Palude del Capitano” is aregional protected area that has been designed only recently and iscomposed by an aggregation of three Sites of Community Importance(SCIs): “Torre Luzzo”, “Torre Inserraglio” and “Palude del Capitano”.Furthermore, these areas followed different steps before they areofficially instituted as natural parks.

In 1987 Torre Guaceto was declared a Wetland of InternationalImportance according to the “Convention on Wetlands of InternationalImportance especially as a water flow habitat”, (the so-called RamsarConvention, 1971). In 1995, in the context of the European Program“Nature 2000”, the area of Torre Guaceto was proposed as a Site ofCommunity Importance (European code: IT9140005) according to theEuropean Directive 92/43, and in 1998 as an Important Bird Area(European code: IT9140008) according to the European Directive 79/409.Finally, in 2000 itwas designated as a national protected area according tothe Italian Law 394/1991.

Saline Punta della Contessa was declared an Oasis of Protection bythe Regional Law n. 751/83. In 1995 this area was proposed as a Site of

Community Importance according to the European Directive 92/43(European code: IT9140003), and as an Important Bird Area accordingto the European Directive 79/409 (European code: IT9140003). In2002 it was designated as a regional protected area according to theRegional Law 19/1997.

Porto Selvaggio e Palude del Capitano was designated as one singleregional protected area according to the Regional Law 19/1997 in 2006.It includes three areas that were proposed as Sites of CommunityImportance in 1995: Torre Uluzzo (European code: IT9150007), TorreInserraglio (European code: IT9150024) and Palude del Capitano(European code: IT9150013).

2. Materials and methods

We applied the approach proposed by Petrosillo et al. (2009), bycompiling a timeseries of land-use and land-covermaps for eachnaturalpark derived from interpreting 1 m×1 m orthorectified aerial photos,according to their availability: for “Torre Guaceto”maps are referred to1954, 1987, 1997 and 2004, while for “Saline Punta della Contessa” and“Porto Selvaggio e Palude del Capitano” to 1954, 1997 and 2006.

We identified 16 terrestrial land-use and land-cover categories todescribe both spatial and temporal landscape dynamics and to assesschanges in natural capital flow based on Costanza et al.'s (1997)ecosystem services valuation biomes model (Petrosillo et al., 2009).The most representative biome was used as a proxy for each categoryand the corresponding ecosystem services coefficient (US $×ha-1 peryear), as proposed by Costanza et al. (1997), is shown in Table 1.

In terms of proxy identification, the classification of permanentcultivations such as Mediterranean scrub, Almond and Olive groves,Reforestation area, Tamarisk, and Juniper, as “Forest”, and not as“Cropland”, depends on the ecological role they play, based not onlyon the intuitive production of goods and services, but also on the roleof sink played by permanent cultivation that is similar to that playedby forest and natural areas as to disturbances across multiple spatialscales (Zurlini et al., 2007; Zaccarelli et al., 2008). Although land-useintensification is at issue as source of disturbances, permanentcultivations are not detrimental to biodiversity; on the contrary,Zaccarelli et al. (2008) demonstrated that they apparently couldbuffer landscape dynamics and disturbances across scales in southernItaly. For each natural park we estimated the Natural Capital Flow(NCF) at time T using the following relationship, modified afterPetrosillo et al. (2009):

NCFT = ∑Ak × VCk

where Ak is the area (ha) for land-use/cover class ‘k’, and VCk isCostanza's Value coefficient (US $×ha−1 per year), which we assumedconstant during the temporal range under study.

For each year considered we estimated the error of digitalization,considering the resolution of the images used to realize themap of landuse (1 m×1 m). Therefore, a buffer of 1 m was created around theperimeters of each polygon of land-cover/land-usemap both inside andoutside. The error of digitalizationwas determined by the estimation ofa buffer value of natural capital flow, considering that, during thedigitalization, each vertex of the polygon could be positioned on theland-cover/land-use class under studywith an error of 1m compared tothe current position. Since itwas hard to establishwhether the error hasbeen determined bymoving the vertex on right or left side of the actualpolygon, the error value has been evaluated as considering the vertexsimultaneously positioned on both sides. Therefore, this procedurecaused an overestimation of the digitalization error.

3. Results

Changes in land-use/land-cover may significantly affect ecosystemprocesses and functions, even though the ecosystem services may not

1117I. Petrosillo et al. / Ecological Economics 69 (2010) 1115–1123

Author's personal copy

necessarily decrease largely if there is a concomitant increase in sizeof other land-cover types that provide a greater level of ecosystemservices (Kreuter et al., 2001). The interpretation of land-use/land-cover changes in terms of NCF changes highlighted several meaning-ful results in the context of natural parks that include NATURA 2000sites. In general, Table 2 shows how small changes in extent canproduce changes of great interest in natural capital flow, for instanceminor changes in the case of wetlands produce significant changes inNCF.

3.1. “Porto Selvaggio e Palude del Capitano” Natural Park

Changes of land-use/land-cover classes have caused the reductionof 12.5% in NCF from 1954 to 2006 (Table 2). The declining of the NCFis associated with the reduction of “wetlands” (from $ 112,292 to $47,770), partially balanced by the increase in “forest” (from $ 338,843to $ 343,469) and in “grassland” (from $ 24,199 to $ 27,354).

The change in the total NCF of this natural park shows a 12.4%decrease from 1954 to 1997, followed by a very small increase (0.10%)

from 1997 to 2006. However, in this last period the decrease is notfully reliable as the digitalization errors for 1997 and 2006 overlap.Therefore, in this interval, the NCF provided by this area could beapproximately considered constant. Surprisingly, even if this areaincludes three sites of community importance, according to theEuropeanHabitat Directive, this official recognition apparently did notproduce any relevant positive effect on the NCF (Fig. 2). The positiveeffects of the institution of the protected area cannot be determinedyet, because of the short period since its establishment, so that it isnecessary to wait for verifying if the presence of the managementauthority and the policies adopted are effective in the restoration ofthe NCF.

3.2. “Saline Punta della Contessa” Natural Park

In the case of “Saline Punta della Contessa” natural park, changes ofland-use/land-cover classes have produced an increase of about 7% inNCF, from 1954 to 2006 (Table 2). The main categories involved showthat the increase in NCF can be associated mainly with the increasing

Fig. 1. The natural parks under study, located in Apulia Region (southern Italy): the National Protected Area of “Torre Guaceto”, the Regional Protected Area of “Saline Punta dellaContessa”, and the Regional Protected Area of “Porto Selvaggio e Palude del Capitano”.

1118 I. Petrosillo et al. / Ecological Economics 69 (2010) 1115–1123

Author's personal copy

of the extension of “lakes rivers” (from $ 290,762 to $ 449,208) and“wetlands” (from $ 1,875,359 to $ 1,987,755), while the other classesshown less significant variations.

The change in the total NCF provided by this area highlights 1.7%decrease from 1954 to 1997, followed by an increase (8.8%) from 1997to 2006, even if in this last case, the reduction is not significant becausethe digitalization errors for 1954 and 1997 overlap (Fig. 3). Therefore, inthis interval, the NCF can be considered rather constant. In any case,despite the protected area has been declared an Oasis of Protection in1983 and a Site of Community Importance in 1995, neither officialrecognitions apparently produced any relevant positive effect on theNCF up to 1997 (Fig. 3). Conversely, the increase in theNCF from1997 to

2006 can probably be attributed to a “conservation effect” in terms ofpositive outcomes determined by the official establishment of thenatural park of “Saline Punta della Contessa” in 2002 (Fig. 3).

3.3. “Torre Guaceto” Natural Park

Changes in land-use/land-cover classes have caused the reduction ofabout 6% in NCF from 1954 to 2004 (Table 2), and it ismainly associatedwith the reduction of “wetlands” (from $ 2,058,072 to $ 1,777,896),partially balanced by the increase of “forest” (from $ 297,386 to$ 455,042).

In more detail, Fig. 4 shows the change in the total NCF of TorreGuaceto natural park with the identification of the different temporalrecognitions of its natural value, highlighting an average decreasingtrend (9%) from 1954 to 1997, followed by an increasing trend (4%)from 1997 to 2004 (Fig. 4).

As Petrosillo et al. (2009) demonstrated, despite the protected areabeing declared International Important Zone in 1987 according to the

Table 1Land-use/land-cover categories identified in the study areas; the most representativebiome used as a proxy for each land-use/land-cover category, and the correspondingecosystem services coefficient (US $×ha−1 per year), as proposed by Costanza et al.(1997).

Land-use/land-coverclass

The most representativebiome

Ecosystem service coefficient(US $×ha−1 per year)*

Urban Urban 0RailroadStreetRocky coast RockSow-able ground Cropland 92Uncultivated ground Grassland 232GrasslandMediterranean scrub Forest 969Almond landOlive grovesReforestation areaTamariskJuniperCoastal beach Coastal beach 4052Periodically underinundation land

Wetlands 14,785

Wetlands

Source: Petrosillo et al., 2009.

Table 2Extension (ha) and Natural Capital Flow (NCF, $) related to the different categories identified in the study areas. % of variation in NCF for “Porto Selvaggio e Palude del Capitano”(1954–2006), “Saline Punta della Contessa” (1954–2006), and “Torre Guaceto” (1954–2004).

Study area Year Extension(ha)/NCF($)

Category

Coastal beach Cropland Forest Grassland Lakes Rivers Rock Urban Wetlands Total

Porto Selvaggio e Palude del Capitano 1954 Extension 0.0 46.2 349.7 104.3 0.7 34.0 1.1 7.6 543.6NCF 0.0 4254.2 338,842.8 24,198.5 5523.7 0.0 0.0 112,292.1 485,111.3

1997 Extension 0.0 23.8 353.7 125.0 0.4 29.0 8.5 3.2 543.6NCF 0.0 2193.5 342,705.3 28,992.3 3314.2 0.0 0.0 47,770.3 424,975.6

2006 Extension 0.0 29.6 354.5 117.9 0.4 29.0 9.0 3.2 543.6NCF 0.0 2725.2 343,468.9 27,354.0 3314.2 0.0 0.0 47,770.3 424,632.6

% of variation inNCF (1954–2006)

0.0 −35.9 1.4 13.0 −40.0 0.0 0.0 −57.5 −12.5

Saline Punta della Contessa 1954 Extension 21.3 2293.2 46.4 0.0 30.6 0.9 5.6 126.8 2524.8NCF 86,198.2 210,969.8 44,945.1 0.0 290,762.3 0.0 0.0 1,875,359.0 2,508,234.4

1997 Extension 13.7 1701.6 18.7 30.0 45.7 7.1 579.0 121.3 2517.2NCF 55,403.0 156,547.8 18,153.2 6965.6 434,220.1 0.0 0.0 1,793,686.6 2,464,976.3

2006 Extension 16.0 1677.6 19.8 32.4 47.3 7.1 586.1 134.4 2520.8NCF 64,860.4 154,335.1 19,163.9 7524.7 449,207.9 0.0 0.0 1,987,754.5 2,682,846.5

% of variation inNCF (1954–2006)

−24.8 −26.8 −57.4 0.0 54.5 0.0 0.0 6.0 7.0

Torre Guaceto 1954 Extension 8.3 875.0 306.9 151.4 0.0 7.3 19.1 139.2 1507.2NCF 33,631.6 80,500.0 297,386.1 35,124.8 0.0 0.0 0.0 2,058,072.0 2,504,714.5

1987 Extension 11.4 895.9 408.3 26.9 0.6 7.4 33.4 120.3 1504.2NCF 46,192.8 82,422.8 395,642.7 6240.8 5698.8 0.0 0.0 1,778,635.5 2,314,833.4

1997 Extensio 10.7 853.1 437.3 33.2 0.7 7.3 46.0 116.0 1504.3NCF 43,356.4 78,485.2 423,743.7 7702.4 6648.6 0.0 0.0 1,715,060.0 2,274,996.3

2004 Extension 10.2 823.0 469.6 27.2 1.1 7.3 45.9 120.3 1504.6NCF 41,330.4 75,716.0 455,042.4 6310.4 10,827.7 0.0 0.0 1,777,896.3 2,367,123.2

% of variation inNCF (1954–2004)

22.9 −5.9 53.0 −82.0 0.0 0.0 0.0 −13.6 −5.5

Fig. 2. Temporal changes of Natural Capital Flow (NCF) in “Porto Selvaggio e Palude delCapitano”, highlighting the different temporal recognitions of its natural value (SCI: site ofcommunity importance; IBA: important birdarea;NPA: institutionof thenatural protectedarea). Bars represent the NCF variability range due to an estimated 2 m averagedigitalization error.

1119I. Petrosillo et al. / Ecological Economics 69 (2010) 1115–1123

Author's personal copy

Ramsar Convention and Site of Community Importance in 1995,neither official recognitions apparently produced any relevantpositive effect on the NCF. Conversely, the increase in the NCF from1997 to 2004 can probably be attributed to a successful conservationof the land-use pattern, given by the capacity to provide the samelevel of ecosystem services during the time (conservation effect)determined by the presence of a management authority of theprotected area of Torre Guaceto in 2000 (Fig. 4).

4. Discussion

TheApulia administration considers all the areas under protection asa network. Thus, the three natural parks under study, including differentsites part of NATURA2000Europeannetwork, can be seen in the contextof a system of all parks involved in providing the flow of natural capital.Therefore, by considering each natural park singularly, they show anincrease or decrease of the natural capital flow in accordance with thesteps they followed before their legal institution and their contextualfactors; but by taking these natural parks into account as a whole, it ispossible to highlight that they currently provide the same amount ofnatural capital flow as about 50 years ago (Fig. 5), even if the recoveryphase is concentrated in the most recent years, when most part ofauthority managements set their control role on the environment.

This demonstrates that the only recognition of an area for its naturalvalue, in terms of Site of Community Importance or Important Bird Area,is not a guarantee for themaintenance of natural capitalflow, and it doesnot satisfy the requirements of the European Union. In fact, the aim ofthe Natura 2000 network is not only to protect but also to managevulnerable habitats and species across their natural range in Europe. In

Italy an important mechanism to do that is the legal establishment ofnatural protected areas that include Natura 2000 sites with the aim notto stop economic activities, but rather to set the parameters by whichthese can take place whilst maintaining the rare species and habitats.Despite there are scarce empirical evidences on the quantitativerelationship between management, and in particular conservationmanagement, and the provisioning of ecosystem services (de Groot etal., 2009), there aremoredirect relationshipsbetweenmanagementandland-use, because dependent on themanagement choices. In this paperwe estimated the natural capital flow as related to land-use change,which in the last period is dependent on the management choices.Indubitably, the natural areas under study should be considered ascomplex systems where different interrelated factors drive each areatowards one or another trajectory. Given the shortness of the periodwhere it is possible to highlight an increase in terms of natural capitalflow, this can be likely attributed to human factor, the fast variable of thesystem. In this context, it is possible to highlight that, on one hand, themanagement authorities have set some best practice guidelines for eco-tourism and for organic agriculture management, in this second casewith the registration of a label for the production of olive oil, but alsosome economic investments in activities aiming at restoring someecosystems, like dunes and wetlands, also limiting the presence ofpeople in some particular areas, and on the other hand, people living inthese areas are becomingmore aware of the presence of a natural park.This, obviously, does not characterize “Porto Selvaggio e Palude delCapitano” for its recent official designation as a regional park.

We recognize that the approach used in this study does notconsider that both the areas under study and the economic valuationsystem are dynamic, changing not only in time but also in space. Theseareas, as multifunctional landscapes are characterized by values thatare determined by the complex interdependencies of three co-evolving subsystems nature, economy and society (Winkler, 2006).In addition, the same type of ecosystem could have very differentvalues in different locations due to differences in ecological role,economic activities, cultures, and the lifestyles of local people. Valuesdepend on current market prices and preferences, so that pastgenerations could value a particular service differently from thecurrent generation (Petrosillo et al., 2009). For instance, if we considerthe natural capital flow provided by wetlands, which represent theland-cover class that presents the highest value in terms of economicvalue, it could be possible to highlight that their value probably waslower in past times. This because if we focus on proximal ecosystemservices (sensu Costanza, 2008) provided by wetlands, it is possible tounderline that in 40 s–50 s some of the ecosystem services related towetlands were not present, such as recreational and cultural services.In addition, in those years wetlands were also the source of a terribledisease (malaria), so that in the hypothetical case of the inclusion ofwetlands in the market in that time they should suffer a depreciation

Fig. 3. Temporal changes of Natural Capital Flow (NCF) in “Saline Punta della Contessa”,highlighting the different temporal recognitions of its natural value (OP: Oasis ofProtection; SCI: site of community importance; IBA: important bird area; NPA:institution of the natural protected area). Bars represent the NCF variability range dueto an estimated 2 m average digitalization error.

Fig. 4. Temporal changes of Natural Capital Flow (NCF) in “Torre Guaceto”, highlightingthe different temporal recognitions of its natural value (IIW: international importantwetland; SCI: site of community importance; IBA: important bird area; NPA: institutionof the natural protected area). Bars represent the NCF variability range due to anestimated 2 m average digitalization error (source: Petrosillo et al., 2009).

Fig. 5. Temporal changes of the total Natural Capital Flow (NCF) considering the threenatural parks under study as a whole. Bars represent the NCF variability range due to anestimated 2 m average digitalization error.

1120 I. Petrosillo et al. / Ecological Economics 69 (2010) 1115–1123

Author's personal copy

in comparisonwith the present days. In the context of the analyses wepresented, these considerations, which can be truthful also for otherland-cover classes, can have effects mainly on the starting point(1954). In this case it could be possible to assume that the resultsshould start from a lower value of natural capital flow, but whatremains set is its most recent temporal dynamics even though theeconomic coefficients proposed by Costanza et al. (1997) areconsidered biased (Kreuter et al., 2001). Even if those involved inthis study consider it an important starting point for furtherassessments and debates of help for environmental decision-makingprocess, not everyone agrees with this approach. Some criticismsconcern that the effort to assign prices to ecosystem services is uselesssince they can never be included in the market (Sagoff, 1997). On theother hand, some believe that, even if these prices can be calculated,they cannot reflect the full value of ecosystem services for ethical andaesthetic reasons to value and protect nature independently from itsbenefits to humanity.

Furthermore, the use of the economic approach is often criticizedas an unsuitablemethodology because of the existence of a conceptualcontroversy about the use of economic approaches applied toecosystems (Pimm, 1997; Norgaard, et al., 1998). This controversy ismainly due to the disagreement between the economic approach andthe ecological approach. The first is based human needs and thereforeevaluates ecosystems according to their usefulness by humans. Thesecond is based on the concept that nature has an intrinsic value thatmankind is unable to value in economic terms.

The values introduced by Costanza et al. (1997) have beenrecognised as biased because they took valuations of particularecosystem services, made in specific parts of the world, and convertthem to “per hectare” values for a particular biome. This brings to theassumption that all hectares of a biome are equivalent not only intheir role but also in the value of the services to local population.

These considerations, surely, affect the valuations presented in thispaper because the used per hectare values are not site-specific and theyneed the application of a sensitive analysis to be better focused on thestudy areas. In any case, the approach introduced in this paper seemsuseful to quantify and compare as a first attempt the change of overallNCF, providedby thenatural parks, under current andpastmanagementregimes. Its specific contribution is to show that the economiccoefficients can be used not only to address purely economical issues,but also to highlight their role, as operational surrogates to evaluate therecent temporal dynamics of the overall flux of natural capital in thestudy areas, even if their values are biased and are considered constantduring the temporal range under study. In this paper the economicestimates of the NCF have been used in a relative sense to simplify thecomparisons of the complex patterns of land-use/land-cover dynamicsand also to quantify the comprehensive change in the flow of NC,considering the natural parks under study as a whole. The potentiallimitations of using changes in land-use/land-cover as a proxy fornatural capital flow are related to the target of this analysis that givesmore importance to the structural component of biodiversity withoutany reference to the compositional and functional aspects. In any case,interpreting land-use/land-cover changes in terms of natural capitalflow allows for the identification of particular situations at risk. In thisway land-covers very susceptible to change during the time andcharacterized by ahighnatural capital value, allow identifying the forcesthat drive the risk, but also which are the resources at risk. For instance,the change detection emphasises that not all changes have the sameimportance, since the significance depends on the variation of NCFrelated to a particular change. A reduction of the extension of wetlandsproduces amuchhigher negative effect to the overall NCF than the sameamount of change related to other land use/cover classes. Moreover, thelandscape context of a natural park can play an important role inmaintaining land-covers and natural capital flow inside the park,because it canmitigate or accentuate the risk to loose the natural capital.Focusing on wetlands, they are affected by human activities in their

entire water catchments, so that they are among the most threatenedecosystems in Europe due mainly to drainage, land reclamation,pollution from outlying factories on the periphery of the wetland andoverexploitation of its resources.

Retrospective analyses, based on the use of different timewindows, allow to determine a change trend, showing NCF changesthat would be masked considering only the extreme years. The resultsobtained analysing different time windows do not match completelywith those obtained analysing only one single time window.

5. Conclusions

NATURA 2000 is not a system of strict nature reserves where allhuman activities are excluded. Whereas the network will certainlyinclude nature reserves, most of the land is likely to continue to beprivately owned and the emphasis is on ensuring that futuremanagement is sustainable, both ecologically and economically (Euro-pean Commission, 2008). Furthermore, spatially explicit values ofnatural capital provided by the landscape across multiple spatial andtemporal scales that might inform land-use andmanagement decisionsare still lacking (Nelson et al., 2009), even though there are somereference papers highlighting the role of the spatial dimension withinthe framework of natural capital (Bailey et al., 2006; Blaschke, 2006;Grêt-Regamey et al., 2008). We highlighted that not all the pastconservation policies applied to the current natural protected areas hadplayed the same role in preserving NCF. Therefore, the only inclusion ofan area into the NATURA 2000 network is not really a guarantee for themaintenance of NCF. The successful conservation of biodiversity regardsnot only the quantity and type of nature being protected or the varioustypes of designations, but also the rigour the competent authorities useto put in practice the conservationpolicy. In this context, thepresence ofa local management authority seems to be crucial to better support theNCF. A management authority, by setting conservation priorities andfocused monitoring systems, can manage effectively the interactionbetween natural habitats and human activities, and determine aconservation effect on natural capital (Petrosillo et al., 2009).

What it is essential, and it is still missing, regards the inclusion ofthe concept of natural capital in planning and managing natural parks(Egoh et al., 2007) that would allow for the development of anintegrated approach to evaluating the merits and congruence ofdifferent conservation policies in maintaining NCF (Balvanera et al.,2001; Singh, 2002; Petrosillo et al., 2009). In this context, somepossible suggestions useful for policy-makers could be:

- to set a system of indicators to monitor land-use/land-coverchange in terms of natural capital flow;

- to implement their conservation policies with best practices useful topreserve the natural capital and to guarantee the economic activities;

- defining the ecological requirements of a species or habitat is onlyone side of the coin; equally important is the process of workingwith stakeholders to find ways to implement the provision ofnatural capital in order to achieve sustainable long-term results.

In conclusion,we suggest to consider the establishedprotected areasas a network where each of them contribute to the overall NCF, and toadopt management strategies more integrated among natural areas.Considering the lacking of data, area-specific value coefficients areneeded tobetter quantify theflowofnatural capital at local scale, at leastfor those ecosystem services recognized as proximal services byCostanza (2008). This could give important insights into the study ofthe dynamics of natural capital flow. For this reason the development ofthis research will be focused both on the quantification of more site-specific coefficients, able to take into account the peculiarity of an area,and on themapping of human perception in terms of values and threatsrelated to natural capital flow to consider the contextual factors that caninfluence the natural capital flow. These aspects integrated can give a

1121I. Petrosillo et al. / Ecological Economics 69 (2010) 1115–1123

Author's personal copy

moredetailed viewof the condition of natural capitalflow in the contextof socio-ecological landscape.

Acknowledgements

We are really grateful to the anonymous reviewers for their helpfulsuggestions andcomments thatmade thefinal versionof this papermoreimproved.Wewant to thank the Province of Lecce and themanagementauthority of Torre Guaceto for the financial support of this research.

References

Abel, S., Cork, S., Gorddard, R., Langridge, J., Langston, A., Plant, R., Proctor, W., Ryan, P.,Shelton, D., Walker, B., Yialeloglou, M., 2003. Natural values: exploring options forenhancing ecosystem services in the Goulburn broken catchment. CSIROSustainable Ecosystems, Canberra.

Alcamo, J., Bennett, E.M., 2003. Ecosystems and human well-being: a framework forassessment. Island Press, Washington, DC.

Antrop, M., 2000. Background concepts for integrated landscape analysis. Agriculture,Ecosystems and Environment 77, 17–28.

Aronson, J., Milton, S.J., Blignaut, J.N., 2007. Restoring Natural Capital: Science, Businessand Practice. Island Press, Washington.

Bailey, N., Lee, J.T., Thompson, S., 2006. Maximising the natural capital benefits ofhabitat creation: spatially targeting native woodland using GIS. Landscape andUrban Planning 75, 227–243.

Balvanera, P., Daily, G.C., Ehrlich, P.R., Ricketts, T.H., Bailey, S.A., Kark, S., Kremen, C., Pereira,H., 2001. Conserving biodiversity and ecosystem services. Science 291, 2047.

Blaschke, T., 2006. The role of the spatial dimension within the framework of sustainablelandscapes and natural capital. Landscape and Urban Planning 75, 198–226.

Berkes, F., Folke, C. (Eds.), 1998. Linking Social and Ecological Systems: ManagementPractices and Social Mechanisms for Building Resilience. Cambridge UniversityPress, Cambridge.

Brody, S., Carrasco, V., Highfield, W., 2003. Evaluating ecosystem managementcapabilities at the local level in Florida: identifying policy gaps using geographicalinformation systems. Environmental Management 32 (6), 661–681.

Chan, K.M.A., Shaw, M.R., Cameron, D.R., Underwood, E.C., Daily, G.C., 2006.Conservation planning for ecosystem services. PLoS Biology 4, 2138–2152.

Chee, Y.E., 2004. An ecological perspective on the valuation of ecosystem services.Biological Conservation 120, 549–565.

Chiesura, A., de Groot, R.S., 2003. Critical natural capital: a socio-cultural perspective.Ecological Economics 44, 219–231.

Costanza, R., d'Arge, R., deGroot, R.S., Farber, S., Grasso,M., Hannon, B., Limburg, K., Naeem,S., O'Neill, R.V., Paruelo, J., Raskin, R.G., Sutton, P., van den Belt, M., 1997. The value ofthe world's ecosystem services and natural capital. Nature 387, 253–260.

Costanza, R., Fisher, B., Mulder, K., Liu, S., Christopher, T., 2007. Biodiversity andecosystem services: a multi-scale empirical study of the relationship betweenspecies richness and net primary production. Ecological Economics 61, 478–491.

Cowling, R.M., Egoh, B., Knight, A.T., O'Farrell, P.J., Reyers, B., Rouget, M., Roux, D.J., Welz,A., Wilhelm-Rechman, A., 2008. An operational model for mainstreamingecosystem services for implementation. Proceedings of the National Academy ofSciences of the United States of America 105 (28), 9483–9488.

Daily, G.C. (Ed.), 1997. Nature's Services: Societal Dependence on Natural Ecosystems.Island Press, Washington, DC.

Daily, G.C., 2000. Management objectives for the protection of ecosystem services.Environmental Science & Policy 3, 333–339.

Daily, G.C., Matson, P.A., 2008. Ecosystem services: from theory to implementation.PNAS 105 (28), 9455–9456.

Dale, V.H., Polasky, S., 2007. Measure of the effects of agricultural practices onecosystem services. Ecological Economics 64, 286–296.

de Groot, R.S., Alkemade, R., Braat, L., Hein, L.,Willemen, L., 2009. Challenges in integratingthe concept of ecosystemservices and values in landscape planning,management anddecision making. Ecological Complexity10.1016/j.ecocom.2009.10.006.

de Groot, R.S., 2006. Functions-analysis and valuation as a tool to assess land useconflicts in planning for sustainable, multi-functional landscape. Landscape andUrban Planning 75, 175–186.

de Groot, R.S., Matthew, A., Wilson, M.A., Roelof, M.J., Boumans, R.M., 2002. A typologyfor the classification, description and valuation of ecosystem functions, goods andservices. Ecological Economics 41, 393–408.

Eamus, D., Macinnis-Ng, C.M.O., Hose, G.C., Zeppel, M.J.B., Taylor, D.T., Murray, B.R., 2005.Turner ReviewNo. 9: Ecosystemservices: an ecophysiological examination.AustralianJournal of Botany 53, 1–19.

Egoh, B., Rouget, M., Reyers, B., Knight, A.T., Cowling, R.M., van Jaarsveld, A.S., Welz, A.,2007. Integrating ecosystem services into conservation assessments: a review.Ecological Economics 63, 714–721.

Ehrlich, P.R., Ehrlich, A.H., 1981. Extinction: the causes and consequences of thedisappearance of species. Ballantine Books, New York.

Ekins, P., 1992. A four-capital model of wealth creation. In: Ekins, P., Max-Neef, M.(Eds.), Real-Life Economics: Understanding Wealth Creation. Routledge, London/New York, pp. 147–155.

Ekins, P., Simon, S., Deutsch, L., Folke, C., De Groot, R., 2003. A framework for the practicalapplication of the concepts of critical natural capital and strong sustainability.Ecological Economics 44, 165–185.

European Commission, 2008. NATURA 2000 network. [online] http://ec.europa.eu/environment/nature/natura2000/index_en.htm.

Farber, S.C., Costanza, R., Wilson, M.A., 2002. Economic and ecological concepts forvaluing ecosystem services. Ecological Economics 41, 375–392.

FoodandAgriculturalOrganization [FAO], 2004. Statistics. [online]http://www.faostat.fao.org.

Grêt-Regamey, A., Bebi, P., Bishop, I.D., Schmid, W.A., 2008. Linking GIS-based models tovalue ecosystem services in an Alpine region. Journal of Environmental Management89, 197–208.

Groffman, P.M., Driscoll, C.T., Likens, G.E., Fahey, T.J., Holmes, R.T., Eagar, C., Aber, J.D.,2004. Nor gloom of night: a new conceptual model for the Hubbard Brookecosystem study. Bioscience 54, 139–148.

Haines-Young, R., Potschin, M., 2004. Valuing and assessing multifunctional land-scapes: an approach based on the natural capital concept. In: Brandt, J., Vejre, H.(Eds.), Multifunctional Landscapes. Theory, Values and History. WIT Press,Southampton, vol. 1., pp. 181–192.

Haines-Young, R., Watkins, C., Wale, C., Murdock, A., 2006. Modelling natural capital:the case of landscape restoration on the South Downs, England. Landscape andUrban Planning 75, 244–264.

Haines-Young, R.H., 2000. Sustainable development and sustainable landscapes:defining a new paradigm for landscape ecology. Fennia 178 (1), 7–14.

Knight, A.T., Cowling, R.M., Campbell, B.M., 2006. An operational model forimplementing conservation action. Conservation Biology 20 (2), 408–419.

Kremen, C., 2005. Managing ecosystem services: what do we need to know about theirecology? Ecology Letters 8, 468–479.

Kremen, C., Ostfeld, R.S., 2005. A call to ecologists: measuring, analyzing, and managingecosystem services. Frontiers in Ecology and the Environment 3 (10), 540–548.

Kreuter, U.P., Harris, H.G., Matlock, M.D., Lacey, R.E., 2001. Change in ecosystem servicevalues in the San Antonio area, Texas. Ecological Economics 39, 333–346.

Kumar, M., Kumar, P., 2008. Valuation of the ecosystem services: a psycho-culturalperspective. Ecological Economics 64, 808–819.

Levin, S.A., 1998. Ecosystems and the biosphere as complex adaptive systems.Ecosystem 1, 431–436.

Levin, S.A., 2006. Learning to live in a global commons: socioeconomic challenges for asustainable environment. Ecological Research 21 (3), 328–333.

Käyhkö, N., Skånes, H., 2006. Change trajectories and key biotopes—assessing landscapedynamics and sustainability. Landscape and Urban Planning 75, 300–321.

Mander, U., Helming, K., Wiggering, H., 2007. Multifunctional land use: meeting futuredemands for landscape goods and services. In: Mander, U., Wiggering, H., Helming,K. (Eds.), Multifunctional land use. Springer, Berlin, pp. n 1–13.

Millennium Ecosystem Assessment [MEA], 2005. Ecosystems and human well being.Island Press, Washington, DC.

Moloney, K.A., Levin, S.A., 1996. The effects of disturbance architecture on landscapelevel population dynamics. Ecology 77, 375–394.

Naidoo, R., Balmford, A., Costanza, R., Fisher, B., Green, R.E., Lehner, B., Malcolm, T.R.,Ricketts, T.H., 2008. Global mapping of ecosystem services and conservationpriorities. Proceedings of the National Academy of Sciences of the United States ofAmerica 105 (28), 9495–9500.

Nelson, E., Mendoza, G., Ragetz, J., Polasky, S., Tallis, H., Cameron, D.R., Chan, K.M.A.,Gaily, G.C., Goldstein, J., Kareiva, P.M., Lonsdorf, E., Naidoo, R., Ricketts, T.H., Shaw,M.R., 2009. Modelling multiple ecosystem services, biodiversity conservation,commodity production, and tradeoffs at landscape scales. Frontiers in Ecology andthe Environment 7 (1), 4–11.

Norgaard, R.B., Bode, C., Values Reading Group, 1998. Next, the value of God, and otherreactions. Special section: forum on valuation of ecosystem services. EcologicalEconomics 25, 37–39.

Papageorgiou, K., Vogiatzakis, I.N., 2006. Nature protection in Greece: an appraisal of thefactors shaping integrative conservation and policy effectiveness. EnvironmentalScience & Policy 9, 476–486.

Pearce, D.W., Turner, R.K., 1990. Economics of natural resources and the environment.Harvester Wheatsheaf, London.

Petrosillo, I., Zaccarelli, N., Semeraro, T., Zurlini, G., 2009. The effectiveness of differentconservation policies on the security of natural capital. Landscape andUrban Planning89, 49–56.

Pimm, S.L., 1997. The value of everything. Nature 387, 231–232.Potschin,M., Haines-Young, R., 2003. Improving the quality of environmental assessments

using the concept of natural capital: a case study fromGermany. Landscape andUrbanPlanning 63, 93–108.

Raymond, C.M., Brown, G., 2006. A method for assessing protected area allocationsusing a typology of landscape values. Journal of Environmental Planning andManagement 49 (6), 797–812.

Raymond, C.M., Bryan, B.A., MacDonald, D.H., Cast, A., Strathearn, S., Grandgirard, A.,Kalivas, T., 2009. Mapping community values for natural capital and ecosystemservices. Ecological Economics 68, 1301–1315.

Roe, E., Van Eeten, M., 2001. Threshold-based resource management: a framework forcomprehensive ecosystem management. Environmental Management 27 (2),195–214.

Sagoff, M., 1997. Can we put a price on nature's services? The Institute for Philosophyand Public Policy. [online] http://www.puaf.umd.edu/ippp/nature.htm.

Singh, S.P., 2002. Balancing the approaches of environmental conservation by consideringecosystem services as well as biodiversity. Current Science 82, 1331–1335.

Tilman, D., Farigione, J., Wolff, B., d'Antonio, C., Dobson, A., Howarth, R., Schindler, D.,Schlesinger, W.H., Simberloff, D., Swackhamer, D., 2001. Forecasting agriculturallydriven global environmental change. Science 292, 281–284.

Walker, B.H., Steffen, W.E., 1996. Global change and terrestrial ecosystems. CambridgeUniversity Press, Cambridge.

1122 I. Petrosillo et al. / Ecological Economics 69 (2010) 1115–1123

Author's personal copy

Wallace, K.J., 2007. Classification of ecosystem services: problems and solutions.Biological Conservation 139, 235–246.

Williams, P.H., Araújo, M.B., 2002. Apples, oranges, and probabilities: integratingmultiple factors into biodiversity conservation with consistency. EnvironmentalModelling and Assessment 7, 139–151.

Winkler, R., 2006. Valuation of ecosystem goods and services Part 1: an integrateddynamic approach. Ecological Economics 59, 82–93.

Zaccarelli, N., Petrosillo, I., Zurlini, G., Riitters, K.H., 2008. Source/sink patterns ofdisturbance and cross-scalemismatches in a panarchyof social–ecological landscapes.Ecology and Society 13 (1), 26 http://www.ecologyandsociety.org/vol13/iss1/art26/.

Zhao, B., Kreuter, U., Li, B., Ma, Z., Chen, J., Nakagoshi, N., 2004. An ecosystem service valueassessmentof land-usechangeonChongming Island,China. LandUsePolicy21, 139–148.

Zurlini, G., Riitters, K.H., Zaccarelli, N., Petrosillo, I., 2007. Patterns of disturbance atmultiple scales in real and simulated landscapes. Landscape Ecology 22, 705–721.

1123I. Petrosillo et al. / Ecological Economics 69 (2010) 1115–1123