4.1. Identification of the Most Important WES
The WES identified by the experts were water for irrigation, water for livestock, drinking water (provisioning services), biodiversity, water regulation, and water purification (regulating services), and aesthetic values and opportunities for recreational activities (cultural services). To select which WES to map, these were ordered according to the importance with which they were rated by the experts [56
]. The final WES identified as most important were six: water for irrigation and drinking water (provisioning), biodiversity and water regulation (regulating), and aesthetic values and opportunities for recreational activities (cultural). Water for livestock and water purification were ranked in last position by the experts and it was therefore decided not to map them. The experts considered that the WES were of medium to high importance and showed a downward trend. They stressed that changing trends in the context of ES were closely linked to management activities implemented in a given area over time. The scale of beneficiaries was identified as local–regional for provisioning and regulating WES and regional–international for cultural WES.
Most of the stakeholders worked in the study area (59%), were men (85%), and had a university education (70%); they were aged between 32 and 76 years (Table 2
Before being asked to identify and map the different WES, the stakeholders were asked if they were familiar with the concept of ecosystem services
. Eleven knew how to define it, twelve had never heard of it, and four had heard of it but did not know how to define it accurately. Following the approach of Iniesta-Arandia et al. [17
] and Raymond et al. [41
], we used the term benefits-contributions
instead of ecosystem services
for the rest of the interview to ensure clarity and minimize educational and cultural biases [17
The content and discourse analysis of the interview transcripts produced 61 codes (Appendix B
). All the interviewees considered that the Muga river basin benefited people a lot or quite a lot. When asked to give an example, the most common benefits mentioned were quality of life, availability of food and the ability to produce fresh vegetables and other products, rich biodiversity of flora and fauna, beautiful scenery, a wide range of opportunities for recreational activities, and a lack of air pollution. These results are of particular interest, as most studies of ES that have used open-ended questions to date have not detected answers related to regulating services [13
]. In general, all the stakeholders, regardless of whether or not they lived in the Muga river basin, expressed a very strong sense of belonging and considered that basin had an almost bucolic air about it. Comments included:
“We like this landscape that has been embellished by the hand of man. It is our cultural landscape, it’s what makes the Alt Empordà beautiful; This area is like the Garden of Eden, it has everything, it offers all the resources we need, it’s wonderful. I’m in love with it”.
DD and ID stakeholders ranked the WES in a similar order of importance (Wilcoxon test, p
> 0.05). Water for irrigation and drinking purposes were ranked first, followed by biodiversity and water regulation. Cultural WES were perceived as important as they were a tourist attraction but they were not considered essential for well-being. Accordingly they were largely ranked in position 5 or 6, in agreement with findings by Raymond et al. [41
] (Figure 3
The number of dots used (points on the map) did not vary significantly between DD (n
= 5688) and ID stakeholders (n
= 5575) (Wilcoxon test, p
= 0.544). Regulating services had the most points (38.1% of total), followed by cultural (36.1%) and provisioning services (25.8%). WES perceived as important but that have few points on the map (e.g., provisioning services) can be considered to be particularly vulnerable, as they are dependent on just a few supply areas. The number of points used to map a WES is not always linked to its perceived importance. Drinking water, for example, is very important, but it was mostly concentrated at a single point, the Darnius-Boadella reservoir. The interviewees also perceived landscapes with aesthetic values as being very valuable in terms of biodiversity and habitats; they therefore typically used similar points to identify regulating and cultural services. The WES with the highest number of points was biodiversity, with 2349 points (20.9%), followed by aesthetic values, with 2056 points (18.3%) (Table 3
). Stakeholders in the DD group used more points to map biodiversity, water regulation, and cultural WES, while those in the ID group used more points to map provisioning WES. DD stakeholders (e.g., crop and livestock farmers) used fewer points to map WES they interacted with daily in relation to their sociodemographic profile and familiarity with WES. Better knowledge of the basin, for example, resulted in more accurate mapping, with a greater focus on the position of provisioning units and better positional accuracy and completeness of each WES. The reliability of data obtained via ES mapping, however, remains to be determined in many cases [58
4.2. Social Perceptions and Spatial Distribution of WES
The WES hotspots mapped out were distributed differently through the basin according to category (provisioning, regulating, cultural) and unit (SPU, SBA, dSPU) (Figure 4
). The provisioning WES hotspots mainly coincided with the Darnius-Boadella reservoir (around 190 points), which is the main source of irrigation and drinking water in the basin [32
]. The Muga river also had two small dams that distribute water to irrigation channels in two key agricultural areas and to a number of towns and villages [59
]. The agricultural plain was also considered a provisioning ES supply hotspot area (with around 230 points), as it contains numerous wells that extract water directly from the underground aquifers. Just eight of the 27 stakeholders considered that the forests and woods in the upper basin had a decisive role in guaranteeing the provision of water to the rest of the basin (around 43 points), contrasting with the views of the experts, who saw forests as having a crucial role in water storage and regulation. The stakeholders, however, did consider that forests in the upper basin (with around 70 points) and the main stem of the river, its tributaries, and the coastal wetlands (with around 530 points) were crucial for water regulation and for the presence and conservation of natural aquatic habitats. These results highlight the importance that stakeholders attach to the AENP in the lower basin and show that they recognized the important role that coastal wetlands play in biodiversity and in minimizing coastal erosion and the effects of heavy rainfall, river overflow, and sea storms [6
]. The cultural hotspots identified were the AENP, the coastline, the high stretch of the river, the river mouth (about 325 points) and the Darnius-Boadella reservoir (around 163 points). These elements were mainly perceived as cultural hotspots because of their natural beauty and the opportunities for recreational activities.
There were no significant differences between DD and ID stakeholders in terms of the number of points used to map SPH, SBAH, or dSPH or in their spatial distribution. As shown in Figure 5
, ID stakeholders used more points to identify degraded SPHs (with the exception of water regulation). By contrast, DD stakeholders used more points to map SBAH, which were mainly located on the coast, in urban areas, and in the agricultural plain.
As for WES categories (Figure 5
), the stakeholders used more points to map regulating SPH (in particular biodiversity) and cultural SPH. In the case of SBAH, water for irrigation and human consumption, aesthetic values, and opportunities for recreational activities were mapped most. dSPH had the fewest points, but hotspots related to water regulation ES (rivers, forests in the high basin, and coastal wetlands) were considered to be the most degraded areas. All the stakeholders recognized the different anthropogenic pressures on the lower part of the Muga river and the AENP, which was considered both an SPH and a dSPH.
Our findings are consistent with those reported by Palomo et al. [25
], who showed that provisioning ES tend to be located outside protected areas, while regulating and cultural ES tend to be located within these areas.
Urban dwellers and national and international tourists were all perceived as WES beneficiaries. Both DD and ID stakeholders, however, mapped regulating SPU and dSPU in the same area. Moreover, our density maps show that DD and ID stakeholders differed in their perceptions of the location of hotspots. For the DD stakeholders, these tended to be located more in natural spaces (rivers, wetlands, and forests), while for the ID stakeholders, they were spatially more spread out and particularly present along the coast.
The analysis of the participatory mapping audio-recordings revealed differences in perceptions according to type of WES category (provisioning, regulating, cultural) and unit (SPU, SBA, and dSPU). For example, in answer to the question, “Where, in your opinion, does irrigation water come from?” or “Which areas supply this benefit?”, the stakeholders typically answered: “Water clearly comes from the sky, is there any other possible answer to this question?”.
When asked to map the WES units, the stakeholders identified humanmade elements, such as the reservoir, wells, irrigation canals, and dams along the river as provisioning SPU and natural elements such as forests, mountains, and rivers as cultural SPU. In a study of the links between cultural ES and urban forest features, Baumeister et al. [52
] showed that people considered humanmade elements to be an important part of cultural services. Our study shows that this was also the case for provisioning and regulating WES in the Muga river basin, which are in theory more closely linked to the ecological functioning of ecosystems than to cultural aspects. Most of the SBA elements were positioned in urban areas, in the agricultural plain, and along the coast (mainly campsites and tourist resorts). Most of the dSPU elements identified were natural features, such as the AENP, the coastline, the agricultural plain, the river and its tributaries, and the river mouth. Nonetheless, humanmade elements, such as irrigation channels, historical-cultural features (mills, factories, and fountains), the reservoir, and urban areas were also identified as dSPU (Figure 6
). It is important to note that while the stakeholders coincided in their choice of dSPH, their reasons varied depending on their profile, highlighting the existence of different value systems that can generate conflicting views [13
], as dependence on a given service would affect perceptions of possible impacts on activities.
The spatial correlation analysis allowed us to explore differences in value systems, visualize potential sources of conflict over the use of water resources, and better understand the power relations that shape decision-making processes [13
] (Table 4
Spatially, the WES supply areas were strongly correlated, indicating that they are sources of potential conflicts and trade-offs. SBAH and SPH, however, were not positioned in the same area, showing that stakeholders perceive that most WES are not “consumed” where they are generated. We also observed a greater overlap between SPH and SBAH among DD stakeholders, suggesting that they perceive lower WES mobilization than ID stakeholders. Similarly, they would appear to perceive themselves as having a close relationship with provisioning WES supply points, probably because changes in supply would affect their activities more than those of ID stakeholders.
Analysis of divergences and factors influencing preferences is crucial for identifying potential areas of conflict or tension and for understanding the reasons behind different choices [12
]. Analysis of trade-offs between WES thus can help identify at-risk areas and potential conflicts between groups of stakeholders. The concept of “trade-off” indicates that the provision of one ES would reduce the provision of another. Therefore, when two ES involving trade-offs are strongly correlated, it means that they are being generated in the same place and may therefore lead to conflict. Trade-offs were identified by the question, “Do you think there is competition for water? And if so, what are the main problems?” [61
]. Based on the answers to these questions, the relationships between WES were classified as trade-offs or bundles (Table 5
We also tested the correlation between different SPH (Table 6
Water for irrigation and drinking water (provisioning services) and water for irrigation and water regulation involved the most trade-offs between each other (r
> 0.80). The correlation coefficients between provisioning services and biodiversity, followed by cultural WES, confirmed that these two categories do not coincide spatially. We also observed that relationships between WES could be negative (trade-offs) or positive (bundles) depending on the direction of the relationship [54
]. For example, an increase in water for irrigation would reduce water regulation, but an increase in water regulation would not increase the availability of water for irrigation. A similar trend was observed for cultural WES, which coincided in terms of position and had clearly opposing trade-off directions. All the stakeholders were of the opinion that an increase in opportunities for recreational activities would result in a reduction in aesthetic values, while an increase in aesthetic values would result in increased opportunities for recreational activities (synergy). An increase in biodiversity was also perceived as positive as it would increase both aesthetic values and opportunities for recreational activities (e.g., bird watching in wetlands). By contrast, an increase in aesthetic values and opportunities for recreational activities would have a negative impact on biodiversity.
Our findings for trade-offs and bundles based on the correlation analysis and interview data shed light on possible sources of conflict or tension among stakeholders in the Muga river basin. Twenty of the 27 interviewees were of the opinion that there was competition for water. The main “concerns” expressed in response to the question “Are you worried about a decline in water resources and if so, why?” (Appendix B
, q4.2) were related to climate change, in particular greater rainfall variability and more intense drought episodes. These concerns echo those raised in a recent study of tourist accommodation owners and managers in the Muga river basin who expressed concerns about the effects of climate change in the basin [62
]. Nonetheless, most of them did not perceive serious risks to the future of tourism or their businesses, and some were even of the opinion that global warming could benefit them by lengthening the tourist season. We found numerous other studies that focus on a sociocultural evaluation of ES, although not specifically in WES, in other countries of the Mediterranean Basin, most of them on the Iberian peninsula [12
]. The results of these researches underlined the need to increasingly apply this type of methodology, mostly in contexts such as the Mediterranean basin, where the relationship between WES and society is so delicate, especially referring to climate change, in one of the most affected areas that has already exceeded the 1.5 °C threshold [4
The stakeholders interviewed in our study were very concerned about loss of biodiversity and habitat destruction and the increased demands on water due to human pressures, particularly from the urban and tourism sectors. The agricultural sector was perceived as the most problematic sector (mentioned by 20 of the 27 stakeholders); this perception is in line with the findings of the European MEDACC LIFE project [38
], which estimated that 75% of all water in the Muga river basin was used for agricultural purposes. The tourism and urban sectors were mentioned as problematic by a similar number of stakeholders (17 and 16, respectively) (Appendix C
). The above perceptions are supported by the results of the mapping exercise. Many stakeholders, however, claimed that conflicts due to competing demands for water arise in times of scarcity. In other words, they are closely linked to climate conditions and the availability of water at a given time. The discourse analysis of the opinions expressed by the stakeholders support the data presented thus far. The agricultural industry was identified as the main consumer of water in the basin:
“All the water from the reservoir goes to agriculture; the levels drop to dramatic levels two months a year and all the water is used for agriculture; there’s no water in the river the rest of the year, we’re outraged, they’re throwing it away”.
The farmers, by contrast, said:
“When there’s a drought, priority is given to urban and tourism uses, and we’re the ones who are most affected. We’re the only ones who change what we do to use water more efficiently, for example, by planting crops that are more suited to the effects of climate change (temperature, rain, wind, humidity”.
These were some of the burning issues that sparked debate among the various stakeholders, confirming the tensions that have historically marked the use of water in the Muga river basin [32
]. Ten of the 27 stakeholders stated that competition was greatest between the agricultural sector and the tourism industry, particularly in the summer months, when water for irrigation is needed most and when the number of visitors to the area (local and international holidaymakers) is at its highest [32
]. Some of the stakeholders from the agricultural sector went into quite some detail on this issue:
“More and more water is needed for general consumption and tourism; the entire coastline consumes a lot of water here in summer. The thing is, this area has always been agricultural; tourism came later and water that used to be for agriculture has been extracted from the aquifers and now there is less. The need for water has increased, but there is no control, nobody is looking at how many showers tourists are taking a day, for example. But everything we do is controlled. But in our case, a high proportion of the water we use goes back to the aquifer”.
The stakeholders also mentioned problems related to the salinization and nitrate contamination of groundwater and water from wells, which reduce the supply of water fit for human consumption and have a negative impact on natural habitats and biodiversity. These issues also spark conflicts between the agricultural sector and conservationists. On the contrary, the stakeholders were of the opinion that the agricultural sector had less influence on decisions regarding water use than the urban and tourism sectors. Thirteen of the 27 stakeholders considered that the agricultural sector had considerable power while 17 thought that was the case for the other two sectors. The majority of stakeholders thought that the conservationist sector had no decision-making power, with just 10 mentioning that they had moderate power. All the stakeholders agreed that the public administration sector had the greatest decision-making power and they mentioned a lack of communication and a prevailing top-down approach (Appendix C