1. Introduction
In recent decades, there has been ample evidence that using market-based instruments (MBIs), as alternative policy instruments to command-and-control, can help improve the provision of ecosystem services and ensure sustainable local development [
1,
2,
3,
4]. These include Payments for Ecosystem Services (PES) – or Payments for Environmental Services - schemes defined by Wunder [
5] as: “voluntary transactions between service users and service providers that are conditional on agreed rules of natural resource management for generating offsite services”.
In order to be defined as PES schemes in the strict sense, they must meet certain preconditions, which Wunder [
6] identifies as a transaction voluntarily; a clear definition of the ecosystem service provided or the resource that provides it; the presence of at least one buyer/user of the service and one seller/provider of the service; and conditionality, namely if the provision of the service ceases or diminishes, payment for it is stopped or reduced. Other preconditions are added to the previous ones, according to Smith
et al. [
7]: additionality, namely payment is made for improvement or maintenance interventions that the provider makes on the resource and that would not otherwise be there; prevention of leakage, in other words an undesirable negative impact on the provision of other ecosystem services or another natural resource to the detriment of the guarantee of the service or the resource protected by the PES scheme; permanence of the service, in the sense that the interventions made by the provider should not have reduced effectiveness and rapid reversibility.
A PES scheme to be defined as such must fulfil all the previous preconditions, if only some of them are met it is defined as PES-like and in a broad sense it becomes an economic incentive or MBI [
8].
Several definitions of PES schemes exist in the literature [
6,
9,
10,
11,
12,
13,
14], which allow for the inclusion of a large part of the world’s PES programmes that do not meet the restrictive criteria proposed by Wunder. But, at the same time, they lead to a lack of harmonisation of results and replication and transfer of experiences from one site to another, due to an non-unique definition [
15,
16]. For the development of this study, the narrowest meaning of the term was considered.
PES schemes originated mainly in countries with developing economies to reduce poverty, environmental degradation, and the economic divide, but today they are also widely applied in developed economies, as witnessed by programmes in Costa Rica [
17], Brazil [
18], Mexico [
19], Vietnam [
20], the United States [
21], Poland [
22], and Finland [
23]. Nevertheless, the geographical areas most targeted are China and the American continent [
24,
25]. It is also important to point out that many PES programmes only exist in grey literature and that some organisations have tried to collect data from them but have produced reports that are difficult to understand [
15].
The main benefits of ecosystem services internalised by PES include regulating services, such as biodiversity protection [
26], hydrogeological protection [
27], and carbon storage [
28]. In recent times, cultural services, such as tourism-recreational activities and health are also gaining recognition [
29,
30].
1.1. Literature review
There are several reports in the grey literature that have provided guidelines or best practices on the design and implementation of PES schemes [
7,
31,
32], while others have collected the different PES currently in place [
33] or have done both [
34,
35,
36,
37,
38,
39]. The problem with these reports is that - apart from not having received a peer-review process - they are often long and complex to read or focus exclusively on PES in countries with developing economies. At the same time, in the scientific literature, several authors have hypothesised methodological frameworks related to PES schemes with more emphasis on some aspects than others; indeed some have focused: on the development of early PES schemes for poor and developing economies [
40,
41]; on the institutional and political economy framework [
13]; on the environmental component with life cycle assessment (LCA) [
42]; on the creation of a PES case study dataset [
43]; on socio-economic outcomes [
44,
45]; on behavioural economics and social psychology for the motivation to conserve and manage a natural resource behind a reward [
46]; on choosing between different alternatives of PES schemes [
47]; on the improvement of already existing methodological frameworks [
24]; and on the integration of a framework containing biodiversity and carbon sequestration [
48].
Most of the frameworks listed above, however, serve for implementing PES schemes and not for their ex-post evaluation. Impact evaluation studies do exist in the literature, but they are carried out for PES schemes implemented in threatened and degraded areas, for conservation and protection or poverty alleviation [
49,
50,
51,
52]. For PES schemes that are instead implemented the suggestions of external organisations, for example by scientific projects (i.e., solution-driven PES scheme; see 2.1.1), and that do not originate to address a threat, but rather to increase the welfare of the local communities, some have identified the successful elements for its implementation [
53] or have done an ex-ante evaluation [
23], but an ex-post evaluation framework is lacking.
This is the context for our research, the aim of which is to investigate which bottlenecks and elements might hinder the success of a solution-driven PES scheme. In this study, a methodological framework for the ex-post evaluation of the design, implementation, and monitoring of a PES scheme was created to respond to our research question. Document analysis, web scraping and semi-structured interviews were the methods used to answer the different blocks of the framework.
3. Results
Figure 2 shows the results from the application of the ex-post evaluation framework. A general description of the individual boxes follows.
The initial interest in the development of a PES scheme in the Medvednica Nature Park was solution-driven because it was chosen as part of a research project (the SINCERE project). The choice of the area as a case study can be supported by the analysis conducted on TripAdvisor.
Figure 3 shows the time trend of the collected reviews both as frequency (3a) and growth rate (3b). The results suggest a bimodal distribution of reviews with peaks in 2013 and 2015 possibly due to specific sports and/or recreational events in the mountains. There is also a sharp decline in reviews in 2020 (a drop of -80%) probably due to the COVID-19 health emergency and a slow recovery from the following year.
Figure 4 shows the reviews by seasonal (4a) and monthly (4b) trends. A constant interest emerges in the different seasons, with a strong peak in the summer period specifically in August and June and in the winter season probably due to both recreational events (e.g., fairs and events) and sports competitions (such as skiing and orienteering).
The continents and European countries of the provenance of the reviewers/tourists are shown in
Figure 5. Europe ranks first as the continent of origin (n=125), followed by America (n=25). In Europe, Croatia is the country with the most reviewers (n=71) due to its proximity to the study area, followed by the United Kingdom (n=22) and Germany (n=5).
In general, it can be inferred that the study area is frequented by a good number of tourists and society living in neighbouring areas continuously throughout the year. The decision to develop a PES scheme for tourism and health aspects is therefore cohesive.
In terms of governance, Croatia has a well-defined legal and institutional framework. It recognises the importance of forests and natural resources in its Constitution and since 1990 has developed ad hoc legislation (Amendments to the Forest Act OG 41/90) for the first Croatian PES forestry, which was a green tax that has now been merged into Articles 65 and 68 of the latest Croatian Forest Act OG 68/18. Regarding institutions, forests are a state competence, as the Ministry of Agriculture with the company Croatian Forests Ltd. oversees forest management, while the Ministry of Environment Protection and Energy deals with environmental protection, which includes forests and natural resources in general (see the various Environmental Protection Acts).
Property rights, however, are only clear for the state park manager, but for the PES scheme to work, the entire Medvednica area must be studied for the provision of its forest ecosystem services. In this area there are several conflicts of ownership between private individuals and little knowledge of their rights as also revealed in the stakeholder interviews (
Table 2).
The stakeholders who participated in the semi-structured interviews used various attributes to express their opinions on PES schemes and the SINCERE project (
Table 2). These attributes are subsequently grouped into four main categories (“emotions”, “elements for the success of a PES”, “difficulties for the implementation of a PES”, and “value added by the project”). Managers were the stakeholders who most contributed to the identification of the attributes (n=15), followed by users (n=13) and consultants (n=9). Concerning the categories, all roles perceived positive emotions in being involved in such a project.
These emotions, as reported during the interviews, changed negatively during the development of the project because of various conflicts and the general perception that nothing would change. Regarding the elements considered most important for the success of a PES scheme, the social component was prioritised, namely good cooperation and mentality of those involved in the implementation of such schemes and increased awareness and education of users and visitors about the role and importance of forest ecosystem services provided by ecosystems. The main difficulties perceived during the development of the PES scheme have to do with the misunderstanding among the stakeholders involved and the users’ and visitors’ conception that nature is free, and thus the lack of demand to trigger the PES mechanism. Finally, according to stakeholders, the SINCERE project has brought added value in terms of its ability to create collaborations and potential new opportunities between stakeholders and in raising of stakeholders’ awareness of the importance of forest ecosystem services. However, negative aspects also emerged from the interviews, such as the perception that the project remained only at a theoretical level and that nothing had changed.
No mapping, biophysical quantification, economic evaluation, or accounting of forest ecosystem services was found.
Regarding the market, participants were asked if they knew what forest ecosystem services were, and most of them answered that they did not know - 106 (68.8%) of them in 2018 and 104 (80%) in 2020. In 2018, 48 visitors stated that they were aware of forest ecosystem services, and the most frequently mentioned services were oxygen production (14 visitors), provision of natural recreational space (10 visitors), protection from soil erosion and fresh air (7 visitors), water treatment, impact on psychophysical health and animal habitat (5 visitors), provision of a natural resting place, health services and air purification (4 visitors). Other forest ecosystem services mentioned were CO2 sequestration, biodiversity, climate change mitigation, tourism, balance management and many others.
In the survey conducted in 2020, 26 visitors responded to know what forest ecosystem services are, and the most frequently mentioned were providing a natural recreational place (11 visitors), oxygen production (7 visitors), water purification (6 visitors), health services and air purification (5 visitors each), and food and timber (4 visitors each). Visitors also mentioned tourism, soil protection from erosion, animal habitat, offering a natural resting place, offering a natural educational site, biodiversity, CO2 sequestration and many others.
Participants were also asked to compare the impact of the experience of visiting the Medvednica Nature Park on health and well-being with commercial products and services (
Figure 6). In a survey conducted in 2018, most respondents (33.3%) compared this impact to a visit to the gym (HRK 35 – about 5 euros - per hour), 20.1% to that of a day at a wellness centre (HRK 150 – about 20 euros - per day) and 15.7% to that of going to the cinema. The lowest number of visitors, 4.4%, compared a visit to the park to a concert worth HRK 200 (about 25 euros).
Similar results were shown in the research conducted in 2020 - 33.8% of visitors compared the effect of a visit to Medvednica to a visit to the gym (HRK 35 per hour), followed by 14.4% who compared it to a day at the spa (HRK 150 per day), and the same percentage who compared it to local trips (HRK 350 – about 50 euros). The smallest number of visitors, 2.9 per cent, compared a visit to Medvednica with an international trip worth HRK 2,100 (about 280 euros).
Regarding the question of the WTP to visit the Medvednica Nature Park (
Figure 7), of the 102 visitors who answered the question in the survey conducted in 2018, 54 respondents (35.3%) answered no, while 99 (64.7%) answered yes. Of the respondents who said yes, 48.5% are willing to pay HRK 10 (about 1.50 euros), 26.3% HRK 15 (about 2 euros), and 25.3% of respondents are willing to pay HRK 5 (about 0.60 euros).
The research conducted in 2020 showed slightly different results than the one conducted in 2018. Although most of visitors are willing to pay Medvednica (54.7%), their share is quite lower than in the research conducted two years earlier. On the other hand, the share is lower, but the amount they are willing to pay is higher - 44.4% of visitors are willing to pay HRK 15, 38.3% HRK 10 and 17.3% HRK 5.
The WTA has not been estimated to compensate landowners and foresters for continuing with their forest management practices in the area for the benefit of the community and at the expense of their private return from productive activity alone (i.e., forest logging).
Intermediaries and knowledge providers were also involved in the development of the PES scheme. The providers were the public administration of the Medvednica Nature Park and private owners. The service users were visitors to the donation boxes and organisations and entities organising events in the park area for one-time concession permits (e.g., Croatian Mountain rescue service and triathlon club). The intermediaries were civil society and business activities (e.g., web service providers). The knowledge providers were research institutions (e.g., Faculty of Forestry, University of Zagreb). During the project, 3 meetings were held between 2018 and 2019 to involve stakeholders from the area. The first meeting involved only 5 stakeholders, in the other meetings their participation increased.
The PES scheme designed with the two mechanisms is private, with a many-to-many configuration due to the different service providers and users, is applied locally and has a validity period equal to the duration of the research project (short-term). Recreational and health services are sold and packaged in the form of piggy-backing as users who buy these services cascade also benefit from others free of charge. In terms of payment characteristics, the source is private, output-based, namely based on the actual delivery of the services, with cash, one-off for the one-time concession permits and periodically for the donation boxes and takes place after the delivery of services.
Regarding the monitoring of effects, it was not possible to assess the mechanism of the donation boxes, because they were vandalised and destroyed. About the one-time concession permits mechanism, reports from the SINCERE project showed that the involvement of different stakeholders in the meetings created in them a greater awareness of forest ecosystem services and the importance to pay for such services. Another result of the project showed that the mechanism allowed for a re-direction of conflicts between the users of the area, because it assigned each group a different area and the funds collected from the permits could be used for investments in recreational infrastructures. Furthermore, there was a monitoring of fauna, flora, and soil damage. As an impact, there is likely to be an improvement of the recreational experience in the park with a consequent increase in demand for recreational services. However, the experience gained from this mechanism has not triggered the feedback or feedback process to improve or implement parts of the PES scheme and its durability.
4. Discussion
PES schemes can contribute to the conservation of threatened areas and ecosystems and to improve the well-being of local communities, as reported by several authors [
49,
80,
81]. For PES schemes to be successfully implemented, however, their effectiveness and efficiency, as well as the results obtained, must be analysed. Otherwise they would remain a mere theoretical exercise and lose credibility as argued by Wunder
et al. [
43]. The framework proposed here aimed to evaluate ex-post a solution-driven PES scheme, independently of the forest ecosystem service analysed. This was done attempting to consider both the political/institutional and social, economic, and environmental components. Our attempt differs from those found in the literature, such as the one proposed by Page
et al. [
42] about the evaluation of local PES proposals by monitoring their environmental impact with LCA, or the one proposed by Schomers
et al. [
82] about assessing the potential of intermediaries to improve the effectiveness of PES schemes, or yet the one proposed by Tikkanen
et al. [
23] for the ex-ante evaluation of schemes applied to nature-based tourism.
The application of the framework allowed us to answer our research question and identify bottlenecks that potentially limited the success of the PES scheme implemented in the Medvednica Nature Park. For a successful implementation of a PES scheme, it is important to have a suitable background, as argued by Brand [
83]. In this regard, the results revealed a strong societal interest in the study area, as also reported by Bakarić
et al. [
70] and Tisma
et al. [
69], and thus the potential for implementing a PES scheme. At the same time, as reported in the study conducted by Vuletić
et al. [
84] on water-related PES schemes in south-eastern European countries, Croatia has more than 30 years of experience with the legal and institutional and thus theoretical framework of PES schemes. The absence of such a factor would likely have led to the failure of the scheme, as argued by the review conducted by Yan
et al. [
85] on PES as an essential instrument for improving ecosystem services. However, the lack of clear property rights among private landowners, as argued by some managers involved in stakeholder interviews, limited the success of the scheme. In a review conducted by Adhikari and Agrawal [
86] on the ecological and social outcomes of PES projects, the importance of property rights and tenure security for a project’s success emerged, as also reported by Yan
et al. [
85].
The methodological framework also highlighted the lack of spatial identification and quantification of forest ecosystem services and the areas with their greatest hotspot within the study area. According to Wunder
et al. [
24] and Ezzine-de-Blas
et al. [
49], who analysed past experiences of PES schemes, these factors are one of the main factors for environmental additionality along with payment differentiation and conditionality. The results indicate a lack of knowledge of forest ecosystem services, which probably led to reduced or no willingness on the part of society to pay for them. During the course of the project, however, as reported by Tisma
et al. [
69] society’s perception and knowledge of such services increased, and this will certainly influence their WTP in future research projects. In this regard, Poudyal
et al. [
87] highlight society’s knowledge of ecosystem services and PES as one of the socio-economic factors affecting the implementation of PES schemes.
In general, the methodological framework revealed potential bottlenecks, especially in the preparatory context for a PES scheme, but the design and implementation were successful in the study area. A final element to be reported is the monitoring of effects that was carried out, but the conditionality for the continuous provision of recreational and health-related services by private landowners was not verified. This may be due both to the fact of the ownership conflicts, mentioned above, that did not make them participate in the park’s PES scheme and to the short duration of this scheme, as it was as valid as the SINCERE research project. There is, however, a need to emphasise the importance of monitoring, verifying conditionality and sanctioning non-compliance, as reported by several authors [
43,
49,
88] so that PES schemes are stable over time and do not become mere economic additions to “business as usual” conditions where the service is either not provided or poorly provided.
5. Conclusions
Recently in the field of environmental economics, there has been a shift from a “polluter pays” approach typical of political and command-and-control-based instruments to a “provider gets” approach, such as that of market-based instruments, capable of creating virtuous and cooperative behaviour among the actors involved. Among MBIs, PES schemes have attracted increasing interest over the past three decades, first as a tool for protecting threatened ecosystems in developing and emerging economies and then as a tool for enhancing ecosystems in developed economies. In this context, there is a need for evaluation frameworks, guidelines and supports that can monitor and evaluate the effectiveness and success of such schemes.
This study attempted to establish an ex-post evaluation framework to identify bottlenecks and obstacles to the success of solution-driven PES schemes by integrating the four main spheres of sustainability, namely environmental/ecological, social, economic, and political into one proposal.
The results expressed a clear societal interest in the area subjected to the PES scheme - given its year-round attendance - but at the same time revealed potential obstructive elements for the successful implementation of such a scheme. The mechanism based on donation boxes for visitors to the park failed due to vandalism. In contrast, the mechanism based on one-time concession permits, which mainly involved organisations and entities organising events and recreative activities in the park, although moderately successful and interesting, had obstacles in the unclear property rights of landowners, the absence of mapping, quantification, evaluation, and accounting of the forest ecosystem services under study, little or no WTP on the part of the demand side for such services, and the absence of application of the feedback process of the functioning of the scheme for its improvement or integration.
In a general sense, the proposed assessment framework lends itself to replication in other geographical contexts with an even greater spatial extent than the local context, depending on the application of the PES scheme. The framework is versatile and can be modified and integrated with other boxes depending on the context, such as the need to integrate local communities’ knowledge of ecosystem services and their uses. For decision-makers and those involved in the development of PES schemes, it can be valuable support in initially identifying the elements that hinder their success, however, there is a need for different technical skills to be able to analyse the different boxes of the framework. For researchers, such a framework can be a first step for the ex-post evaluation of PES schemes at the academic level and an element on which further research can be developed to overcome the limitation of its application only for solution-driven cases. Such cases are in the minority compared to PES schemes created to protect an ecosystem or to support landowners and foresters in their management practices.