The work presented hereafter is part of a larger mapping and assessment of ecosystems and their services carried out in Portugal (Marta-Pedroso et al. 2014), as foreseen in action 5 (“Member States, with the assistance of the Commission, will map and assess the state of ecosystems and their services in their national territory by 2014, assess the economic value of such services, and promote the integration of these values into accounting and reporting systems at EU and national level by 2020”) of Target 2 of the EU Biodiversity Strategy (“By 2020, ecosystems and their services are maintained and enhanced by establishing green infrastructure and restoring at least 15% of degraded ecosystems”).

Given this context and considering the arguments in favour of the use of economic valuation as a tool to ensure that economic benefits provided by protected areas are properly considered in decision-making, as well as the challenges it poses, the aim of the present study is two-fold: to contribute to enhance current EU Member States' experience in mapping and assessing economic value of ecosystem services in the context of the EU Biodiversity Strategy to 2020 (Action 5) and to present a non-primary data-based methodology to bring the economic value of Protected Area to the decision-making process. To pursue this goal, we have selected the Natural Park of Serra de São Mamede (PNSSM) as a case study.

The Natural Park of Serra de São Mamede (PNSSM), located in the inner-central part of Portugal, within the Alentejo NUTS II region, was created by the Decree-law 121/89 of 14^th which has been since amended by the Decree-law No. 20/2004. This decree, which is currently in force, reclassified the PNSSM by defining its new limits, specific objectives for protection, managing and monitoring procedures, management authorities and restriction settings (i.e. forbidden activities and the permissible hunting activities). Regarding the park’s new limits, the need for amendment has arisen from the assessment taken under the scope of Natura 2000 establishment and also from studies carried out envisioning the development of land use conditionings for the park. Indeed, both assessments revealed contiguous areas to the former park limits of high natural values, which motivated the park's enlargement. Also underlying the park reclassification was the need to refrain from land-use changes that were threatening the unique character of the landscape occurring within the park, whose preservation depends on human presence and in the maintenance of traditional land uses.

In its current definition, the PNSSM covers an area of 56021ha, embracing the Municipalities of Arronches, Castelo de Vide, Marvão and Portalegre and being limited to the East by Badajoz province (Extremadura, Spain) - Fig. 1. The land use/cover (LUC) within the park, based on the most recent available land use/cover national cartography (COS 2007) is dominated by forests, open forests and shrubland, which represents, respectively, 22% and 38% of the park’s area (Fig. 1).

Figure 1.  

Location and Land use/cover (LULC) of PNSSM following national cartography (COS 2007 level 2).

The PNSSM includes the mountain ridge called “Serra de São Mamede”, which is the only range south of the River Tagus with climatic conditions that allow the presence of Atlantic plants and therefore contributes to the variety of remarkable habitat and plant diversity within the PNSSM. Indeed, the PNSSM is completely confined within the São Mamede Natura 2000 Site of Community Interest (SIC) - PTCON0007, established by the Council Ministers’ Decision No. 142/97 of 28 August, representing around 45% of the site’s area (Fig. 1).

Within the park, there is a carbonated aquifer with 8 km² which can offer annual water supplies of 7.7*10⁶ m³/year. Until recently, this was the main urban water supplier to the municipalities of Castelo de Vide, Marvão e Portalegre and also the main source of water for agriculture in the region. Additionally, within PNSSM, there is an industrial mineral water collecting and bottling facility with high relevance to the local economy. Indeed, water resources have always been an important resource to the region with some arguing that the abundance of water springs was responsible for the Romans settling in the region (Vermeulen et al. 2010).

The present zoning of the PNSSM, defined by the Council of Ministers' decision 77/2005 of 21^st, distinguishes fives zones regarding the protection/conditioning level imposed (Fig. 2), which we list hereafter in descending order of protection level:

Figure 2.  

PNSSM protection levels.

Areas of Total Protection – areas with predominance of recognised high natural and landscape values, including geological, landscape and ecological formations, with a high degree of natural conditions and which, taken as a whole, are of exceptionally high ecological sensitivity;

Areas of partial protection (Type I) - areas that contain natural and landscape values whose meaning and importance, from the point of view of nature conservation, are taken together as relevant or, in the case of exceptional natural values, have a moderate sensitivity;

Areas of partial protection (Type II) - areas containing natural and landscape values whose significance and importance, from the point of view of nature conservation, are taken together as relevant, which contain natural values that depend on the uses of soil, water and traditional agricultural and/or forestry systems and which act as buffer or transition zones for the total protection areas and the partial type I protection areas, and may also contain structuring elements of the landscape;

Areas of complementary protection (Type I) - areas where the values of nature conservation and the physical structure of the territory are aligned and where it is intended to reconcile the current use of the soil with the natural and landscape values;

Areas of complementary protection (Type II) - remaining areas of less value for nature conservation, which correspond to areas of more intensive land use where it is intended to reconcile human intervention and local social and economic development with natural and landscape values and objectives of nature conservation.

The hierarchical analytical framework applied in this study, which combines participatory, biophysical assessment and economic value estimation and mapping methods, comprised three stages: a) inventory of relevant ecosystem services (ES) delivered by the PNSSM based on local stakeholders perception evaluation; b) investigation of which of the ES selected by local stakeholders were liable to be biophysically mapped and valued with information readily available; and c) estimation and mapping of the economic value of ES. This framework presents an induced selection of ES, in the sense that it may be the case that only some of the ES identified as relevant by stakeholders are considered for economic valuation (and mapping) (Fig. 3). Information availability and its readiness for the purpose of mapping economic values of ES delivered by the PNSSMand perceived by local stakeholders, were the major determinant of the final suite of ES for which we have estimated and mapped the economic value.

Figure 3.  

Induced selection of ecosystem services (ES) considered in this study.

Stakeholders’ involvement in PA (Protected Areas) management is of the utmost importance as success of conservation and management measures relies on their acceptance by local stakeholders (Niedziałkowski et al. 2018, Sterling et al. 2017). This is particularly important for the present case as most of the area within the PNSSM is privately-owned.

The use of maps and spatial-based valuation methods of ES in the context of natural resources management and PA management, is supported by the spatial nature of ES, e.g. their heterogeneity in space (Marta-Pedroso et al. 2014a, Maes et al. 2016) and by their advantages as visualisation and communication tools into decision-making processes (Potschin et al. 2016).

Our definition of (local) stakeholders is aligned with the one proposed by Sterling et al. 2017 and therefore it refers to individuals or groups who directly rely on or impact the specific targets of resource management or conservation action (e.g. indigenous landholders, farmers, fishers, local non-governmental organisations or local researchers). Stakeholders identification started with a brainstorming session between the research team and local contacts about whom to specifically invite or consult with and how to engage those individuals or groups. As described above (Case Study) and despite restrictions in terms of land use, maintenance of human presence and traditional economic activities are of the utmost importance for the maintenance and long term preservation of the high natural and landscape values of the PNSSM and, hence, coverage of sectoral activities taking place within the PNSSM was a major criterion in selecting stakeholders. Despite this group of primary stakeholders, local media, locals NGO (Non-Governmental Agencies) and opinion leaders (e.g. former politicians) were also engaged. In addition to specific interests, impacts or dependencies on the PNSSM, diversity of age, gender and education also guided the selection made. Based on the stakeholder analysis performed, representatives of local stakeholders were invited to participate in a one-day participative workshop. Invitations were sent via e-mail and later confirmed by telephone. The workshop aimed at capturing stakeholders’ perception on the values of PNSSM. Although there are different approaches to capture stakeholders' perceptions of value (Mascarenhas et al. 2016), we opted for an invited participative workshop as it allowed gathering different visions and perceptions on the PNSSM and their services in a short time (Younge and Fowkes 2003).

The workshop was structured in different activities for different purposes, but overall the aim was that stakeholders could (i) identify all ecosystem services (ES) provided by the park (Fig. 4a) and (ii) prioritise these ES based on a points-system (Fig. 4b).

a

b

Figure 4.

Main activities developed in the participative workshop with stakeholders

a: Identifying all ecosystem services present in the park  
b: Prioritisation of all ecosystem services identified based on a points-system (blue circles = one point/vote)  

For the first activity, participants were randomly divided into six groups and each group was asked to focus on a particular ES section (provisioning, regulating and cultural services - 2 groups per section). All of the ES listed by participants were written down in this phase, with no screening or restriction whatsoever. Next, the groups of each section were joined together to discuss the ES listed and provide a final consensus list of ecosystem services. The final lists, one per ecosystem service section, were then pinned to the wall and used in the subsequent activities.

For the second activity, each participant was given 3 points/votes per ES section (provisioning, regulating and cultural) to attribute to the services they considered most relevant. The points could be attributed as preferred (i.e. three points to the same ES or one point to three different ES of a given section). All participants used all of their points/votes.

To avoid biasing the perception of participants regarding the ecosystem services (ES) delivered by the park, we have refrained from providing them with a pre-classification list of ES. Instead, we simply explained the concept of ES and allowed participants to freely list what they considered to be benefits people derive from the park’s natural areas, providing assistance whenever required and steering the discussion as little as possible to ensure participants indeed understood what ES were. In this regard, translating the ecosystem services, listed by stakeholders to a common classification (i.e. CICES) in a post-workshop phase, provided a good basis for standardisation of our results while guaranteeing stakeholder’s perspectives were unbiased and fully comprehensible in our methodology. Additionally, by using a two-step method to help stakeholders identify the ES delivered by the park (i.e. first a round-table discussion per group followed by a consensus discussion involving more than one group), we aimed at avoiding biases that could arise from opinion monopolisation (Palomo et al. 2011).

Once local stakeholders’ perceptions and relevant ES listing were known, we narrowed down the set of relevant ES to which biophysical and economic dimension could be spatially quantified, based on data availability and readiness of its use for our purpose. Based on this screening, a final set of six ES was included in this study: Crop production (CP), Extensive Animal production (AP), Fibre production (FP), Carbon sequestration (CS), Erosion regulation (ER) and Biodiversity, in terms of its cultural heritage (Biodiversity heritage - BH). In the next section, we explain how the mapping and valuation exercises were carried out.

Economic methods for mapping and assessing ecosystem services principally involve measuring and accounting for the spatial variation in the economic value of ecosystem services and structuring this information to support decision-making and the design of policy instruments. If we refer to the cascade model (Potschin and Haines-Young 2011), economic methods operate on the right side of the ecosystem services cascade model to quantify the benefits to humans. Any economic mapping or assessment therefore fundamentally relies on biophysical data and methods to quantify the capacity of ecosystems to supply ecosystem services (i.e. the left side of the cascade model) (Maes and Burkhard 2017).

A total of 25 stakeholders representing different interests, dependencies and impacts on the park attended the workshop (Fig. 5).

Figure 5.  

Profile of local stakeholders participating in the workshop. (Residents refer to those living within the park but whose professional activity is not directly dependent on the park).

In Table 3, we summarise the ES identified as relevant by local stakeholders through the participative workshop, following their reclassification using the CICES (v5.1) system. It turns out that, amongst the ES perceived by participants as being delivered by the PNSSM, a total of seventeen ES were listed as relevant (i.e. received at least one point). Considering the points attributed, cultural and provisioning services were the most valued, receiving a total of 41% and 31% of the points, respectively.

Following the analytical framework adopted, once data availability and readiness of use for our purpose were evaluated, our mapping and economic valuation of ES was restricted to six out of the seventeen ES identified as relevant by local stakeholders. As explained in the methodological section, it is not feasible to map economic values without mapping the biophysical dimension of ES (annual flow in our case). Based on this fact and to reinforce such constraint but also to highlight that maps of different dimension of ES can provide different insights for PA management, we present both the biophysical and economic value (Figs 6, 7, 8, 9, 10, 11) for each one of the six ES. The reader should bear in mind that to produce economic value maps, economic valuation methods were applied (Table 2). The designation of each ecosystem service was simplified for practical purposes, but we provide the CICES code in square brackets for comparison with the services listed above in Table 3.

Figure 6.  

Spatial quantification (left) and economic valuation (right) of Crop Production service [1.1.1.1] within PNSSM.

Figure 7.  

Spatial quantification (left) and economic valuation (right) of Extensive Animal Production service [1.1.3.1] within PNSSM.

Figure 8.  

Spatial quantification (left) and economic valuation (right) of Fibre Production service [1.1.1.2] within PNSSM.

Figure 9.  

Spatial quantification (left) and economic valuation (right) of Carbon Sequestration service [2.3.5.1] within PNSSM.

Figure 10.  

Spatial quantification (left) and economic valuation (right) of Erosion Regulation service [2.2.1.1] within PNSSM.

Figure 11.  

Spatial quantification (left) and economic valuation (right) of Biodiversity (as heritage) [3.1.2.3] within PNSSM.

Before addressing value figures, we would like to stress that our purpose is to provide methodological guidance to integrate ES into PA management rather than absolute value figures for the PNSSM. Moreover, the aggregated estimation of economic value presented in this section does not include all the ES listed by local stakeholders as relevant (e.g. water availability and quality are not included in our estimation). Additionally, as mentioned earlier in this paper, our estimations are based on non-primary data and therefore we are aware of possible bias introduced by that fact. For instance, we consider the economic value of erosion regulation as deserving more caution in reading and interpreting the results we present here, as we further elaborate later in our discussion.

By multiplying the annual economic value estimated for each ES (€.ha^-1) by the area of each pixel where it occurs and summing the results, we obtained an aggregated value map for the park (Fig. 12). Despite the considerations mentioned above, the aggregated value was estimated at around 33.2 Million € per year (Table 4). If we exclude the value of erosion regulation, the annual aggregate value of the park is set around 11.3 Million €. Negative values indicate carbon emission rather than carbon sequestration.

Figure 12.  

Aggregated economic value of the PNSSM.

To gain further insight into the spatial value heterogeneity, we present a breakdown of the results per ecosystem services and per land-use typology in the park, following the national LULC cartography (COS 2007 level 2). Based on our findings (Table 4), forests and shrubland are the ecosystems contributing most to the park’s annual economic value.

Given the greater expression of forests and shrubland ecosystems within PNSSM in terms of area (Table 4), we performed a per hectare analysis to compare the value of services delivered by different ecosystems (Fig. 13). Results show that permanent crops deliver higher value of provisioning services (750 €.ha^-1.year^-1), whereas forests and shrubland ecosystem deliver higher value of regulating and cultural services (over 500 €.ha^-1.year^-1).

Figure 13.  

Aggregate ecosystem service value (€.ha^-1.year^-1) per ecosystem typology within PNSSM.

In order to compare the estimated economic value of each ES with its value as perceived by stakeholders (Fig. 14), we have considered the percentage of economic value for each service, given aggregated economic value of ES (right column) and the percentage of points attributed to each service, given the total amount of points attributed to the six ES that were valued (left column). Results indicate that provisioning services combined received around 55% of the points attributed by stakeholders, being thus perceived as highly valuable, but their estimated economic value accrues to less than 30% of the aggregated park value. Additionally, Erosion Regulation seems to be undervalued by local stakeholders, as it received the least amount of points (5%) but its estimated economic value accounts for over 60% of the park’s aggregated value. This result should be critically interpreted given that the apparent imbalance between perceived and estimated economic value for erosion regulation should be framed in the context of how less visible regulating services are perceived but also regarding the potential bias introduced by the data used for estimating the economic value of erosion regulation. Indeed, as highlighted below, when erosion regulation is removed from the analysis (bar to the right in Fig. 14), we see a much less marked difference between perceived and estimated economic value. We further elaborate on this result in the discussion section.

Figure 14.  

Perceived value by stakeholders vs. economic value estimated for the six ecosystem services delivered by PNSSM (provisioning services in blue, regulating services in grey, cultural services in green).

Since the economic valuation performed in this study had a spatial component, we could estimate the average economic value of each ES within park areas that have different protection levels (Fig. 15). Results indicate that service value does vary with protection level. On average and excluding Crop and Livestock Production, all ES have an increase in value when going from areas with no protection restriction to areas with protection restrictions. However, most ES have maximised average values at a partial protection level. Biodiversity is the only service with slightly higher average economic value in park areas of total protection.

Figure 15.  

Average economic value of each ecosystem service (ES) inside the different levels of protection established in PNSSM. Squared markers = provisioning ES; round markers = regulating ES; diamond markers= cultural ES.