Evaluating Ecotourism Sustainability Indicators for Protected Areas in Tehran, Iran

: Ecotourism in protected areas facilitates responsible travel to natural places that conserve the environment, deliver economic beneﬁts to local communities, and offer interpretation and education to visitors. Proper planning and sufﬁcient monitoring of ecotourism sustainability indicators is needed to manage visitor activities in protected areas. Therefore, identifying the major impacts and mitigating them in the early stages of ecotourism development could contribute signiﬁcantly to the achievement of sustainable development. There is a current gap between the situation in the ﬁeld and academic contributions to this problem in protected areas of Iran. In the present study, we evaluated ecotourism sustainability levels in four different types of protected areas in Iran, including Lar National Park, Jajrud Protected Area with Sustainable Use of Natural Resource Areas, Tangeh Vashi National Natural Monument, and Kavdeh Wildlife Refuge. We developed a comprehensive list of ecotourism sustainability indicators, including 38 indicators in the environmental–physical dimension, 42 indicators in the demographic–social dimension, and 30 indicators in the economic– institutional dimension. Harnessing local community expertise, we adopted a Delphi approach to determine sustainability levels and factors impacting sustainability. Ecotourism in Lar National Park was most sustainable because of the high levels of restrictions protecting the area and the difﬁculty in access. Conversely, ecotourism sustainability was lowest at Tangeh Vashi National Natural Monument, which allowed for an uncontrolled inﬂux of visitors. We discuss further factors that impact sustainability, such as population growth, expanding urbanization, an increase in physical and economic activities, and extended annual periods of ecotourism activities. Although the presented ecotourism sustainability indicators are speciﬁc to Iran, this study can also be seen to provide a template to plan for sustainable ecotourism in other countries. Altogether, our results suggest conducting a type-by-type analysis of the particular circumstances of various protected areas.


Introduction
Protected areas are needed to conserve nature and its environmental, cultural, and socioeconomic value [1,2]. Providing ecotourism experiences in protected areas helps conserve nature while offering economic and educational benefits to communities and visitors [3][4][5]. Sustainable ecotourism has been promoted as an alternative to mass tourism, fostering community empowerment and environmental protection [6][7][8]. However, multiple conflicting goals of protected areas may cause a dilemma between resource protection community, and the economic welfare of the local community. Jamal and Stronza [45] found that an evolving partnership between local and international stakeholders toward local control could be helpful for sustainable ecotourism in protected areas of the USA. Zhang et al. [46] identified 52 indicators in accordance with sustainable tourism development goals in Qinghai Lake Nature Reserve, China. Recently, Hasana et al. [47] used a bibliometric analysis, providing a comprehensive overview of the literature on ecotourism in protected areas with the aid of three bibliometric indicators: quantity, quality, and structural indicators. They found a steady growth in publications with a significant increase in citations, implying ecotourism in protected areas is a significant research area.
In this research, we present a detailed examination of sustainable ecotourism indicators and levels for four different types of protected areas in Iran, including a national park, a protected area with sustainable use of natural resources, a national natural monument, and a wildlife refuge. We adopted a Delphi method to identify and evaluate factors influencing levels of sustainability in these areas, drawing on community expertise. Hence, the goal of our research was to (1) identify and assess ecotourism sustainability indicators using the Delphi method, (2) evaluate the level of sustainability of ecotourism offers in the protected areas of Tehran, and (3) determine the main impacts of unsustainable operations in these areas.

Protected Areas of Tehran Province
We selected four different types of protected areas located in Tehran province, Iran, for study, namely Lar National Park, Jajrud Protected Area with Sustainable Use of Natural Resource Areas, Tangeh Vashi National Natural Monument, and Kavdeh Wildlife Refuge ( Figure 1 and Table 1). The selection was based on increasing unmanaged tourism activities in these areas, land use/land cover (LULC) changes, progressing urbanization, and the uncontrolled expansion of various physical and economic activities.
Lar covers an area of 35,765 ha and is located about 70 km from Tehran. There are 405 plant species and 159 animal species know in this area [48].The predominant vegetation and animal species include pasture plants, as well as Ovis orientalis and Capra aegagrus. In addition, the main habitat of Salmo trutta fario can be found here, one of the rarest aquatic species in Iran [49,50]. Jajrud covers an area of about 74,811 ha and is located in the Tehran metropolis. In this area, 517 plant species have been identified, the most important of which are Astragalus species. As for animal species, O. orientalis and C. aegagrus are the most dominant [50,51]. Tangeh Vashi covers an area of 3650 ha and is located about 160 km from the metropolis of Tehran. The main animal species identified in Tangeh Vashi are O. orientalis and C. aegagrus. The dominant plant species is Ferula galbaniflua [52]. Kavdeh covers an area of 76,900 ha and is located in Firoozkooh city, 160 km from the Tehran metropolis. In this area, 405 plant species and 159 animal species have been identified, including O. orientalis, C. aegagrus, Panthera pardus saxicolor, and Canis lupus. The vegetation type is predominantly pasture plants and grasslands [17]. Figure 1 depicts the location of the studied areas.

General Framework
This study was survey-based, and data were collected from documentary and field studies. The present study consists of two parts: (1) the design and extraction of sustainable ecotourism indicators along physical-environmental, demographic-social, and economicinstitutional dimensions; and (2) the evaluation of ecotourism sustainability levels based on the opinion of the local community. A cluster sampling method of community residents was performed, yielding 352 samples in Lar National Park, 382 samples in Jajrud Protected Area with Sustainable Use of Natural Resource Areas, 293 samples in Tangeh Vashi Tangeh Vashi National Natural Monument, and 341 samples in Kavdeh Wildlife Refuge. These samples were selected using Cochran's formula with a confidence level of 95%. Tables 2-4 list 110 indicators accrued from a literature review and study of previous research. Indicators were selected considering various criteria, including their relevance, scientific precision, measurability, transparency, adaptability, comparability, cost efficiency, territorial representation, temporal representation, sensitivity, and communication [53,54].
Respondents were asked to rate their viewpoints and level of agreement on a Likert scale ("strongly agree = 5", "agree = 4", "neutral = 3", "disagree = 2", and "strongly disagree = 1") as to the ecotourism sustainability in the studied areas. To achieve a consensus among the different views, we used the Delphi method, which has been widely applied in numerous tourism works focused on ecotourism indicators [25,55].  Table 3. Sustainable ecotourism indicators in the demographic-social dimension.

Variable Indicators References
Satisfaction Satisfaction with ecotourism of local communities [11,24,25,28,34,43,[56][57][58][60][61][62][63][64][65][66][67][68][69][71][72][73][74][75][76][77][78][79][80][81] Satisfaction with behavior of local communities and their acceptance Satisfaction with maintaining welfare facilities and tourism infrastructure Satisfaction with maintaining local facilities and services Satisfaction with maintaining cultural, historical, and archeological monuments Satisfaction with maintaining vegetation and trees Satisfaction with maintaining animals Satisfaction with maintaining the environment against pollution Satisfaction with environmental health status Satisfaction with road traffic situation Participation Level of participation in protection of nature and natural monuments Level of participation in protection of plants, trees, and green spaces Level of participation in planting seedlings Level of participation in protection of animal species Level of participation in feeding animal species Level of participation in photographing or filming animal species Level of participation in protection of historical and archeological monuments Level of participation in protecting water resources from pollution Level of participation in keeping nature clean Level of participation in protection of tourism infrastructure Table 3. Cont.

Rules and regulations
Level of adherence to laws and regulations Access to local laws and regulations Our list of ecotourism sustainability indicators includes the three physical-environmental, demographic-social, and economic-institutional dimensions across 22 variables, including 38 indicators in the environmental-physical dimension, 42 indicators in the demographic-social dimension, and 30 indicators in the economic-institutional dimension.

Delphi Method
The Delphi method is a structured process to predict and help in decision making to reach group consensus following multiple survey rounds [82,83]. It simplifies complex problems, especially when there is limited information and knowledge or disagreement in the studied field [84]. The main components of the Delphi method include consultation with a group of experts, controlled repetition and feedback, anonymity, analysis of results, and reaching consensus [85][86][87].
In our study, experts were selected from academia, encompassing related scientific fields such as environmental engineering, ecotourism, tourism management, geography, tourism planning, travel and tourism services, and hotel management. To identify and evaluate factors influencing sustainability levels, we queried 40 experts on 37 factors from the physical-environmental, demographic-social, and economic-institutional dimensions. Then, experts were asked to rate each factor on a five-point Likert scale to determine to what extent they agreed that these factors decreased sustainability.
The Delphi process consisted of three rounds. In the first two rounds, the same questionnaire was administered and then repeated. In the third round, responses were presented to participants, who were asked to evaluate and rate their initial responses. Altogether, 36 questionnaires were completed and analyzed. Finally, a consensus was reached in evaluating sustainability levels in the studied areas.

Participant Demographics
Survey participants from local communities were mostly male and between 40 and 50 years old. A considerable percentage of local participants held a diploma (Table 5). Most participants had resided in their respective communities for more than 25 years. Among the respondents, most were between 30 and 40 years old (45%). In terms of education level, respondents had a high level of education; 20% had an M.Sc. degree, and 80% had a Ph.D. degree. Moreover, they were selected from among academics scientific fields, including 12% in environmental engineering, 30% in ecotourism, 20% in tourism management, 7% in geography and tourism planning, 18% in travel and tourism services, and 12% in tourism and hotel management.
Travel and Tourism Services -

Evaluation of Ecotourism Sustainability Levels
The ecotourism sustainability levels for Lar National Park, Jajrud Protected Area with Sustainable Use of Natural Resource Areas, Tangeh Vashi National Natural Monument, and Kavdeh Wildlife Refuge were evaluated (Table 6). High ratings were achieved for most environmental-physical and demographic-social sustainability factors for Lar National Park, with a mean of 4.71 and 3.82, respectively (Table 6). That means that these factors contribute to high levels of sustainability in Lar National Park. Economic-institutional sustainability was rated most highly for Jajrud Protected Area with Sustainable Use of Natural Resource Areas, with a mean of 3.71. In Tangeh Vashi National Natural Monument, demographic-social dimensions were most important, although they achieved a mean of only 2.81 below the midpoint. In Kavdeh Wildlife Refuge, environmental-physical dimensions were thought to be most important, reaching a mean of 4.02. Overall, ecotourism sustainability levels in Lar National Park were rated to be the highest, with a mean of 4.01, whereas the opposite was the case for Tangeh Vashi National Natural Monument, reaching a mean of 2.34.

Factors Decreasing Ecotourism Sustainability
As described above, the Delphi process was repeated across three rounds. The results of the first two rounds are presented in the Supplementary Files (Tables S1 and S2), whereas the results of round 3 are presented in Table 7. As demonstrated in Table S1, 38 and 36 indicators were extracted in the first and second round of the Delphi process, respectively (Table S2). In the first round, the following factors were removed: "existence of abundant water resources" and "a high number of restaurants and food stores" (Table S1). Likewise, in the second round, the factor "natural attractions exist" was removed from the questions (Table S2). In the third round, 35 factors were identified, including 16 factors in the environmental-physical dimension, 8 indicators in the demographic-social dimension, and 10 indicators in the economic-institutional dimension ( Table 7). Table 7 shows the factors that have a negative impact on sustainability. In Lar National Park, the most problematic factor was livestock overgrazing, with a score of 4.22. In Jajrud Protected Area with Sustainable Use of Natural Resource Areas, the level of access to ways and roads caused the greatest issues, with a score of 4.48. In Tangeh Vashi National Natural Monument, an increased number of tourists and visitors was most problematic, reaching a score of 4.27. Finally, in Kavdeh Wildlife Refuge, low numbers of guard stations and environmental guardians impacted sustainability, with a score of 4.20.

Discussion
In the present study, we evaluated ecotourism sustainability, harnessing community opinion in different types of protected areas in Iran. Ecotourism achieved the highest levels of sustainability in Lar National Park. This national park is most protected because of the legal restrictions and prohibitions aligned with IUCN recommendations [88][89][90]. Accordingly, the main goal of national park management is to minimize the impacts of human activities, such as the development of ecotourism activities [2]. Consequently, visitation to this area is limited to the summer months. Entry and participation in ecotourism activities here requires a license from the Department of the Environment as the custodian of the areas. Another reason for the comparatively high sustainability levels is the long distance from human habitats, a low level of infrastructure and tourism services, a high number of guard stations and environmental guardians, high levels of monitoring and control of ecotourism activities, access restrictions, and limited development of ecotourism due to high levels of slope and altitude. These combined factors have led to increased sustainability levels in this area. Conversely, the main factor impacting on ecotourism sustainability here is livestock overgrazing by nomads (the number of livestock exceeds the capacity of pastures), which has decreased the volume of vegetation, especially of high-density pastures. For example, Törn et al. [91] confirmed the impacts of ecotourism activities on vegetation in the natural areas of Finland, and the results indicated that these impacts lead to delays in the restoration of vascular plant species. Other factors affecting the sustainability of ecotourism in this area include the area's high potential for developing ecotourism activities; the existence of various famous tourist attractions; and uncontrolled movement of visitors for hunting, walking, mountaineering, and rock climbing. These findings have been confirmed by other studies [49,50,[92][93][94], demonstrating the significant issues associated with the development of human activities and insufficient protection of the ecological sensitivity of this area.
Conversely, ecotourism sustainability was lowest in the Tangeh Vashi National Natural Monument because of the lack of monitoring of the entry of visitors, especially on weekends and holidays, permitting large numbers of visitors access. Furthermore, the lack of adequate tourism infrastructure led to a decrease in sustainability, increased habitat destruction, and the extinction of valuable species in this area. High levels of tourism activities and their impacts on vegetation considered important in this area include horse riding, vehicles being driven off-road, trampling, erosion and short cutting, soil compaction, disturbance, changes to hydrology, and increased direct vegetation clearance. For example, Pickering et al. [95] showed that horse riding was a critical issue for vegetation conservation and ecotourism sustainability. Horse riding negatively impacts ecosystem sustainability, principally through trampling, resulting in loss of vegetation, erosion, and changes to hydrology [95,96]. In contrast to the studied national park and national natural monument, human activities have not been controlled well in Tangeh Vashi National Natural Monument [89,90], leading to an increasing influx of visitors without a sufficient monitoring system in place to protect the many historical, natural, and cultural attractions. Additionally, soil compaction, disturbance, and erosion are all well-documented adverse effects of ecotourism use due to trampling [97,98]. Other studies have confirmed these findings [72,99,100]. The results indicate that the continued human exploitation of this area will lead to increased unsustainability and the destruction of valuable national resources.
The Jajrud Protected Area with Sustainable Use of Natural Resource Areas is located within the city limits and is fully exposed to population growth, expanding urbanization, an increase in physical and economic activities, development of tourism activities, short distance from human habitats, extended annual periods of ecotourism activities, and increasing visits to the area. The presence of humans in and around the protected areas has often threatened their effectiveness, in some cases causing ecosystem decline despite the protected status [101,102]. Sustainability levels have decreased considerably because of poor management and development of physical and economic activities. High levels of access to ways and road, high levels of human activities, and LULC changes are particularly problematic. These findings have been confirmed by other studies [50,51,94,103], which revealed that the development of human activities, especially economic exploitation by various organizations and ecotourism activities, has led to the extinction of species and decreased biodiversity in this area.
Finally the Kavdeh Wildlife Refuge area suffers from insufficient numbers of guard stations and environmental guardians; a lack of necessary protective equipment for the monitoring of ecotourism activities; and the presence of hunters, which has led to increased poaching and threat to animal species. Similar to our results, interviews with protected area managers of 93 protected areas globally suggested that only one factor was significantly correlated with protected areas' ability to deter habitat change: the density of guards in the protected area [104]. Kavdeh Wildlife Refuge reached the highest levels of sustainability behind Lar National Park. These findings have been confirmed by other studies [17,105]. The most important factor affecting sustainability in this area is the low number of guard stations and environmental guardians, which is a particular problem, considering the high levels of poaching, even in areas dedicated as wildlife refuges.
Despite some limitations, our findings provide a good starting point for further research on various types of protected areas. It is suggested to use the same indicators with MCDA methodologies (e.g., TOPSIS, fuzzy TOPSIS, fuzzy AHP, and fuzzy ANP) to compare the results.

Conclusions
Identifying and evaluating factors influencing sustainability can assist protected area managers in the proper planning and development of sustainable ecotourism operations [41,106]. In the present study, we evaluated and analyzed ecotourism sustainability in four different protected areas in Iran. Sustainability indicators can be used for decision making and to prioritize strategies for medium-and long-term planning of ecotourism in protected areas. Our results demonstrate that ecotourism consists of opportunities and threats for protected areas. A lack of proper planning and insufficient monitoring in our study areas led to a decrease in sustainability. The level of decrease depends on the type of protected area; protected areas that were more restricted in their use achieved higher levels of sustainability. According to the IUCN, various protected areas have specific management objectives and need to achieve multiple goals (education, research, conservation, and recreation). Accordingly, the development of sustainable ecotourism in protected areas needs to consider the quality of visitor experience; the quality of life of the local community; protection of natural resources; and the balance between the needs of the local community, visitors, and the environment. Overall, ecotourism sustainability levels in Lar National Park were rated to be the highest, with a mean of 4.01. Therefore, restrictions in Tangeh Vashi National Natural Monument (total mean of ecotourism sustainability level = 2.34) and Jajrud Protected Area with Sustainable Use of Natural Resource Areas (total mean of ecotourism sustainability level = 3.00) are needed to protect the tremendous ecological sensitivity and significance of these areas.
The results of this study highlight the importance of classifications of protected areas in association with different levels of management and intervention. For example, development of ecotourism in national parks and natural monuments needs to be small-scale (extensive tourism) and well monitored because of the high ecological sensitivity and value of these areas. Other protected areas, such as wildlife refuges, might accommodate larger-scale developments (intensive tourism), noting that such development brings decreased levels of sustainability.