A Theoretical Model as a Contributing to Sustainable Tourism in Protected Areas: Machalilla National Park, Ecuador

1. Introduction

In the face of the challenges posed in the 21^st century, tourism must configure its activities for the sake of innovation and continuous improvement, allowing it to adapt to the changes and transformations that constantly occur in the political, environmental and socioeconomic landscape. The situation implies the constant transformation of old practices by new methods and attractive and innovative tourism policies, with a sufficient capacity to offer new products and services adapted to the new situation [1,2].

Given the nature and impact of tourism for socioeconomic development, it constitutes a critical component that must be taken into account in the management of protected areas. It must be recognized that, in this context, the relationship will always be complex and often conflictive; however, the possibility of its regulation is possible in a climate of adequate balance between tourism management and protection interests. The modeling of tourism in protected areas must incorporate systemic management based on endogenism and the enhancement of natural resources with criteria that respect the environment and the sustainable use of natural resources [3].

Tourism in protected areas is considered as part of the well-being policies developed for the Millennium Assessment [4]. These policies address the need for freedom of choice and action, good social relations and the satisfaction of life needs.

The tourism modalities practiced in protected areas promote a healthy lifestyle in society, contributing to individual subjective well-being and active participation in social life in accordance with different theories including self-determination [5], the theory of subjective well-being [6], the value-based quality of life index [7] and the theory of needs-based well-being [8].

At present, tourism holds key socioeconomic, cultural and environmental importance for social development. At the same time, traditional models tend to generate social inequalities and consume high amounts of energy and natural resources, calling into question the sustainability of these territories [9]. The negative effects derived from tourism on the environment, culture and lifestyles of various populations have led to a demand for more sustainable growth in tourism [10].

Since the second half of the 20^th century, some authors have questioned the theory of unlimited development, highlighting the planet’s limited resource capacity and the natural environment’s diminishing ability to assimilate pollution generated by human activity. Thus, if current consumption rates continue, a growth limit may be faced in the next 100 years [11,12,13].

The Stockholm Declaration in 1972 by the United Nations marked the beginning of discussions between industrialized and developing countries on the links between economic growth; air, water and ocean pollution; and the well-being of the world's population [14].

It is necessary to promote tourism models that are friendly to humanity and the environment, break with the excessive consumption of products and natural resources, and put an end to the exaggerated generation of polluting residuals in watersheds, soil and air [15].

In this regard, researcher Baños Castiñeira posited that it is necessary to appeal to the so-called complementary tourism offer and, within this context, to tourism in protected natural areas (ENP) as an appropriate way to achieve the diversification of destinations linked to new leisure formulas. It is important to consider that tourism is an activity that is susceptible to incorporating territorial policies aimed at achieving the socioeconomic balance of regional spaces, based on the complementarity of tourist offers developed from local endogenous potential [16].

In tourism activity, there is progressive diversification of tourist products and destinations, with an increase in demand for nature tourism, ecotourism activities, visits to national and natural parks, rural tourism and community tourism, among others. Tourists increasingly demand that their travel experiences bring them meaning; to do so, they seek direct contact with native cultures, cultural authenticity, relationships with local communities, and direct contact with flora, fauna, unique ecosystems and nature in general, emphasizing its protection [17].

In Ecuador, protected areas are consolidated based on Article 24, Section 7 of the Organic Code of the Environment, which establishes the declaration of the areas that will be integrated into the subsystems of the National System of Protected Areas and defines the categories, guidelines, tools and mechanisms for their handling and management [18].

The paradigm of sustainability to reduce irreversible environmental impacts implies growing interest in the development of tourism based on parameters of environmental preservation, social equity, quality of life and respect for cultural identity [19].

The tourism model for protected areas must take into consideration a group of dimensions and variables, which are key to achieving sustainable tourism activity. These include the generation of trust and security, the protection of employment, the establishment of protocols and procedures that respond to the use of space and resources in a sustainable manner, the promotion of innovation and social responsibility in the different tourism processes, the incorporation of sustainability in all its dimensions, and prioritization of the demand for inclusive and accessible tourism, in correspondence with what was indicated by the authors of [20,21].

The authors of [22,23] referred to the new challenges of post-COVID-19 tourism. They criticized traditional tourism models and incorporated new tourism demands in a strategic prospective design of new tourism, which arises with a strong demand from clients to establish closer contact with nature and distance themselves from mass tourism.

In the new scenario, the types of tourism practiced in protected areas constitute an effective way of uniting communities, support institutions and human resources to carry out a vision of sustainable development with the ability to reconcile objectives and goals, which allow achieve greater economic efficiency with social equity, cultural identity and preservation of natural resources [24].

The World Tourism Organization (UN Tourism) has created the Sustainable Tourism Network (REDTURS), which can provide support for the strengthening of tourism modalities practiced in protected areas [25].

For the design of the tourism model in protected areas, it is necessary to consider that the administrative and institutional management of protected areas should not be restricted solely to environmental protection and leave human interaction within communities in the background, as an element of special importance for its proper management [26,27].

It is necessary to consider the active participation of the community in protection, through the provision of tangible benefits, such as community participation, the enjoyment of the benefits of sustainable tourism activity and the impacts of protected areas on their lives [28,29,30,31,32].

Understanding the attitudes and perceptions of society in relation to tourism activity in the context of protected areas is an issue that is relevant for the design of protection strategies based on sustainable development. Regardless of what is established in legal matters in the interest of protection, policies aimed at achieving the support of communities through increasing opportunities for shared benefits should be promoted [33,34,35,36].

Authors have developed research [29,36,37,38,39] that demonstrates community approval for the development of tourism in protected areas, as well as other cases where strong social opposition to such projects is evident. The analysis of these elements can be useful when designing a sustainable model for tourism in protected areas that has the support and active participation of the resident community.

The preceding analysis underscores the significance of this research, which configures a theoretical model for sustainable tourism in protected areas. The objective is to offer a theoretical contribution to adapt current models and improve tourism activity in protected areas, correcting the difficulties that exist from traditional practices, which do not adequately respond to the current challenges faced by the tourism sector in the territory and especially in the context of the protected area of Machalilla National Park in Ecuador.

Tourism generates 4.4% of the world's gross domestic product and provides employment to 200 million people. Through an appropriate sustainable tourism model in protected areas, the tourism sector can support sustainable management at the community level as an alternative focused on the market and the provision of services to a growing volume of travelers, who seek to find, understand and enjoy the natural environment [17], which has become more important in the post-COVID-19 pandemic period.

At present, the world's heritage of living species is more threatened than ever, due to the practice of development models that do not guarantee sustainability and exert great pressure on biodiversity. A sustainable tourism model can contribute to the protection of natural resources through raising the awareness among inhabitants of the value of what they possess and the importance of its conservation [17].

The financial resources generated by tourism activity can be crucial in supporting the implementation of environmental protection measures in protected areas. These funds are essential for financing information, interpretation and education programs for visitors and residents, related to the planning, management and supervision of tourism operations in protected areas.

Based on the preceding analysis, a theoretical model is proposed as a contribution to sustainable tourism in protected areas, which starts from theory to evaluate—through a complex methodological procedure—a tourism model that promotes innovation and the use of endogenous resources and strives to valorize the natural resources of the environment through their sustainable use.

A protected area is “an area of land and/or sea especially dedicated to the protection and maintenance of biological diversity, as well as associated natural and cultural resources and managed through legal or other effective means” [40].

Protected areas constitute a cultural artifice with a long history. Two millennia ago, they were used in India to delimit specific areas dedicated to the protection of natural resources. In Europe, they were used a millennium ago with the aim of protecting hunting grounds for the rich and powerful. The notion of protecting places with special characteristics is a universal concept, evident in the traditions of communities in the Pacific with the Tapu areas and in parts of Africa with sacred forests [41].

The first protected areas were decreed by kings and other rulers during the European Renaissance, especially as royal hunting grounds. Over time, these places began to be visited by the public, laying the foundations for community participation and tourism. In 1832, the American poet George Catlin proposed the creation of a state park for the conservation of humans and animals, capturing the primitivism and natural beauty of Aboriginal peoples and cultures in the North American East. However, the first national park was established by law in 1872 in Yellowstone in the United States of America, designating it as a public space or place of recreation for the benefit and enjoyment of the population [17].

In 1866 in Australia, 2000 hectares were reserved for protection purposes for tourism. In 1885, Canada decided to protect its hot springs in the Rockies, which later became Banff National Park. The railway companies saw the creation of the park as an excellent opportunity to stimulate the growth of traveler numbers through tourism [17].

Several forest reserves were created in South Africa at the end of the 19^th century. In 1894, Tongariro National Park was created in New Zealand. As common features in the creation of all these protected areas, it can be noted that they were created at the initiative of governments, the delimited areas were extensive and integrated relatively natural environments, and the parks were available for public enjoyment; so, from the beginning, tourism activity was a foundational element in the creation of national parks [17].

Since the inception of protected areas, the union between the population and the territory has constituted its backbone, considering the population and its culture as integral parts of the concept, along with the land and natural resources. In the 20^th century, the creation of protected areas spread on a global scale. Almost all countries have passed laws in this regard and determined the protection of certain areas. In 2002, approximately 44,000 places had been designated as protected areas, covering almost 10% of the planet's land surface. As time has progressed, the concept and meaning of a protected area have evolved, with some countries emphasizing cultural values. In recent years, concern about marine environments has also increased [42].

The development of ecology has had an influence on the evolutionary process of the concept and meaning of protected areas, leading to a deeper understanding of the need for planning and resource management with a systemic and systematic approach. This evolution has given rise to the classification of protected areas [43], which redefines the protection of biodiversity as a starting point and recognizes the importance of other objectives such as recreation and tourism. This recognition has led to public interest in these areas, and tourism has grown to become a key element of social culture.

Tourism in protected areas promotes the relevance of their local, regional and national importance. It is possible that, at some point, the park system will be understood as part of the park tourism system. The economic relevance of protected areas is increasingly valued based on their environmental performance, particularly in relation to the supply of drinking water and the control of the effects of climate change [44]. Especially since the adoption of the Convention on Biological Diversity (CBD) in 1992, greater attention has been paid to the development of national protected area systems as a means of conserving biodiversity and achieving other objectives [45].

Some protected areas are part of international networks, whether global or regional in scope. There are calls to fully recognize the role of indigenous peoples in relation to protected areas [46] and encourage international cooperation in transboundary protected areas [47]. Figure 1 shows the categorical classification of protected areas.

According to the management objective, recreation and tourism are among the purposes of all categories of protected areas, except category Ia, which corresponds to the strict nature reserve. The protection of biodiversity is not the only purpose, although it is required that there be a special policy to protect and maintain biodiversity [48].

Marine protected areas have recently gained greater recognition. There are more than 2000 marine protected areas, representing approximately 2.5 million km². These include terrestrial spaces, reefs, seagrass meadows, shipwrecked vessels, archaeological sites, brackish coastal lagoons, mudflats, marshes, mangroves and rock platforms [49].

When considering the complexity in the management of protected areas, it can be said that there is much to do to improve the effectiveness of their management [50]. It is important to consider that when there is tourism, the precise management frameworks and strategies are foreseen, in the interest of guaranteeing that the natural and cultural values of the protected areas are maintained. It must be ensured that access for tourist purposes is adequate. It is a relevant challenge that implies the issuance of complex judgments about the mutual concessions between tourism development, the protection of the value of resources and the interests of the local community.

Tourism in protected areas is reactivated from the conception of tourists. The need to encounter the other to seek exchange with exotic populations and landscapes, and the search for a return to nature as a source of physical and mental health constitute two ideological conceptions that favor the choice of recreation and recreation based on one's own environment of protected areas [51].

The sustainable tourism model for protected areas seeks to offer spaces and a tourism practice that emerges from unique experiential experiences based on the exchange of diverse cultures and the enjoyment of natural landscapes, which satisfy the preferences of tourists and a return to the nature as a source of health and life.

Cultural exchange has a special meaning for tourism in protected areas that promotes knowledge of ancestral manifestations and cultures that are an inseparable part of the identity of the people. Museums play an important role in public education and the preservation of national, regional and local identity [52,53]. Together with the archaeological areas and sites, they constitute an attraction for visitors who prefer to enjoy the values of the community. An example is the Community Tourism Museum in Aguas Blanca [54]. Tourists who visit the facility appreciate the archaeological and cultural pieces as an attraction of special significance.

In Ecuador, tourism in protected areas emerged in the 1980s due to the influx of rural tourism and indigenous tourism, which emerged as a response from the indigenous peoples and Montubio nationalities to the exploitation of natural resources by large oil companies and agricultural companies, which sowed poverty and environmental pollution at the cost of depleting the country's natural resources.

The pioneering manifestation of tourism in protected areas in Ecuador occurred in 1979 in the community of Agua Blanca located in Machalilla National Park in the province of Manabí [54,55]. Weak tourism promotion efforts for this type of tourism hindered the dissemination of these experiences. Now, the most important thing is to embrace a sustainable tourism model for protected areas that can provide a methodological procedure capable of filling the gaps of other tourism models and creating a management environment based on innovation and endogenism to face the challenges posed by the changing situation of the world today.

As background, we can cite the study carried out in Japan in 2006 [56]; it was shown that the community in compliance with the institutional regulatory framework, self-regulation linked to protection, high community environmental awareness and the existence of associations constitute elements key to achieving the success of tourism activity in protected areas.

On the African continent, research was carried out linked to the acceptance of tourism by a Ugandan community. The work was carried out in the community of Bigodi, and the results revealed that residents believe that tourism creates community social development, improves agricultural markets and generates income and prosperity [57].

Another investigation was developed in Turkey in 2011 to determine limitations related to tourism due to the lack of identification and classification of nature tourism resources. During the investigation, a group of natural resources was identified and classified, and their tourist value was determined. The results showed that the level of environmental degradation in the studied area was very low, which required an approach that revealed a high potential for tourism development [58]. Other studies with similar objectives were developed in the Latin American area in Belize [59], Dominica [60], Peru [61] and Brazil [62].

Some Ecuadorian authors have reflected on the challenges facing tourism, especially after the COVID-19 pandemic, and warned of the need to rethink tourism models. They consider that the sustainability of tourism should no longer be supported by discourses of unrealistic projects separated from compliance with sustainability indicators [63].

The proposed sustainable tourism model for protected areas is based on a process of evaluation and continuous improvement, which makes it possible to evaluate and improve the system based on the real situation in which it is developed. It is based on the experiences provided by other models, but adapted to real conditions and regulations established based on local resources to offer unique solutions and unforgettable experiences.

For the development of the sustainable tourism model for protected areas, some experiences from other studies based on the review of sources were considered, and the initiatives and lines of tourism products were identified as mechanisms that allow for the development of tourism activity in accordance with the requirements of protection that the territory requires [64].

Other research has delved into the study of community-based tourism management models aimed at sustainable community development. The model is composed of phases of diagnosis, planning, programming, execution and closure, and includes the actions to be executed and the tangible results [65].

Other studies have concluded that tourism ventures in the province of Manabí require a profitable economic dimension due to their organizational structure integrated with natural, cultural and human resources and capabilities, which require economic investment for its maintenance [66,67].

In the studies that precede the proposal of the sustainable tourism model for protected areas, it can be seen that they did not achieve a level of exhaustiveness that allows for the evaluation of actions related to the problems posed by tourism activity in protected areas. Some studies focused on the economic aspects, entrepreneurship and management of tourism within the framework of local development, while others focused their efforts on evaluating tourism management under extraordinary health situations.

The sustainable tourism model for protected areas aims to evaluate tourism management in a comprehensive manner. It begins with governance and relations with the social environment and the promotion of a systematic climate of innovation and continuous improvement based on the social component of the environment, demand, and supply and the balance of these indicators—problems that have not been sufficiently addressed in other studies.

The external components of the model and integrated management are analyzed through seven units of analysis which, in a dynamic and inter-related way, respond to the requirements of tourism modeling based on endogenism and the tourism value of natural resources as well as relations with the social environment, innovation and continuous improvement. This approach allows the articulation of a system of tourist satisfaction that is controlled and fed back in a systematic and permanent way from management aimed at the formation of new enriching knowledge of a sustainable tourism practice.

The scientific problem is as follows: How can sustainable tourism development be guaranteed in protected areas, in a manner that is capable of facing the changes that the context imposes and responding to the tourism challenges of the future?

The objective of the article is to propose a theoretical model as a contribution to sustainable tourism in protected areas, which provides a theoretical–methodological basis for its practical implementation that makes it possible to confront the challenges imposed by future tourism.

1.1. Theoretical Delimitation

1.1.1. Theoretical Models of Tourism and Their Relevance

Theoretical models of tourism constitute a scientific result that allows the expression of the relationships between variables for the functioning of the system [68]. They are valuable theoretical solutions that fulfill important functions in providing explanation, description and prediction, enabling a predictive transformation of reality. The relevance of theoretical models lies in their ability to abstract tourist reality and achieve its synthetic representation with its complex and multiple relational causes synthesized in complex circumstances and events.

The bibliographic review allows us to observe the existence of multiple classifications of tourism models. Theoretical models allow the connection of the reality of tourism management with theory as a tool to understand and verify sustainable tourism within the context of protected areas and generate new hypotheses that enable the evaluation of the effect of natural dimensions and variables in accordance with the interests of sustainable tourism. The main qualities of theoretical models are coherence, inclusiveness and ease of understanding [69].

Some authors have analyzed different theoretical models of tourism based on the understanding of the operating mechanisms and their structural organization. They considered the models described in diagrams and studied them in four groups: in the first case, they analyzed it from a spatial model approach; in the second case, they studied it from its fundamental relational elements; in the third case, they studied it from a systemic approach of models; and, in the fourth case, they studied it for the study of structural models [69].

De Armas et al. argued that both the model and the system are scientific results and constitute contributions that make it possible to obtain new knowledge about the object of research, through the analysis of the close links that exist between the model and the system, as the model always has a systemic character and the system is best understood when it is expressed through a model. Therefore, the scientific methods and procedures of modeling and the systemic approach are combined, which requires theoretical reflections consistent with its specificities. Modeling is a special form of mediation, where the model is similar to the object being investigated and constitutes its copy as it has a scientific character and organic unity [70].

Theoretical modeling for tourist activity represents an opportunity that allows the appreciation of the object under study, interpreting it and evaluating it integrally or in parts, depending on the problem that is to be solved as part of the research exercise and the epistemological foundations that the researcher handles [71].

The researcher Trujillo developed an analysis of the management of tourism companies and presented a model to promote tourism in the city of Guaranda with the use of a qualitative and descriptive approach [72], considering the contributions of other authors [73,74]. To model tourism promotion, the author considered the studies carried out in [69,75] and, in relation to promotion 2.0, they utilized the criteria of [76,77].

Franco-Bravo et al. developed theoretical studies of 12 tourism models to interpret the functioning of the system. They examined some models for analysis and the derived implications for tourist destinations. Their research revealed that theoretical models are useful for several purposes, including the ability to express and simplify reality as well as predict the formulation of theories [78].

As a result of other research work, a model was created from the consideration of a schematic sequence to define the stages of a sustainable local tourism management model. The analysis focused on management models that considered the sequential stages of planning, organizing, directing and controlling [79].

1.1.2. The Sustainable Tourism Model for Protected Areas

Designing a sustainable tourism model for protected areas is not a simple task, considering that within such delimited areas, various modalities of tourism, such as nature tourism, rural tourism, community tourism, and even sun and beach tourism, can converge.

During the research, the results of the work carried out by Cabanilla were considered based on the historical evolution of tourism in Ecuador from 1989 to 2011 [80]. A table is shown that chronologically synthesizes various concepts based on the criteria of different authors and reflects the different names, emphases and perspectives of the concepts [81,82,83].

One of the issues that has not been sufficiently defined is related to the indicators of sustainable tourism, as a model that is based on the use of local endogenism and sustainability as a basic appellation to ensure the preservation of nature that serves as a setting for the developed tourist activities [84,85].

For the design of the sustainable tourism model in protected areas, it is important to consider the results of the research carried out by Navas-Ríos, which emphasizes the role of the local community as a provider of significant tourism products based on its natural and cultural resources as well as social capital. The community plays a key role in promoting, developing and implementing a fair, equitable and sustainable economy through the control and preservation of the tourism product it offers. At the same time, it actively participates in conserving natural resources and sociocultural wealth while satisfying the needs of visiting tourists. This approach focuses on providing quality experiences that are lived and shared with the local society, allowing tourists to become aware of and learn about local aspects and community wisdom [86].

The contribution of [86] allowed us to understand the concept of sustainable tourism in its dimensions and indicators linked to its evolution by integrating its main characteristics that are repeatable, which facilitated the scientific conceptual development of the sustainable tourism model for protected areas.

Other contributions are related to public management and governance. These include the relationships between tourism actors with national, local and regional governments, environmental protection, the sustainable use of resources in response to tourism demand and alliances between the public and private sectors [87].

2. Materials and Methods

Tourism began to develop in Ecuador as an economic activity in 1930 with the enactment of the Tourism Promotion Law [88]. In 1947, operations began with the creation of the first travel agency, Ecuadorian Tours, which began to develop variants of mass tourism. In later years, other variants of alternative tourism emerged as an important socioeconomic factor in disadvantaged areas, especially those that exist in rural environments [89].

The National System of Protected Areas of Ecuador includes 26,208,785.38 hectares, representing 19.42% of the territory. Due to the geographical location of the country, there is a high level of biodiversity. It has 14 national parks: Machalilla, Cayambe, Coca, Cotacachi-Cayapas, Cotopaxi, Llanganates, Sangay, El Cajas, Podocarpus, Yacuri, Antisana, Sumaco-Napo-Galeras, Río Negro Sopladora and Yasuní T/T [90].

This research was carried out in Machalilla National Park (PNM), which is a protected natural area (PNA) located in the Ecuadorian coastal territory, specifically in the south of the province of Manabí. It occupies part of the municipal territories of Puerto López and Jipijapa, in the parishes of Puerto Cayo, Machalilla, Julcuy and Puerto López [90]. In 1979, a community tourism establishment was founded in the Agua Blanca community, which is currently located within the limits of Machalilla National Park [54].

The PNM was created on July 26, 1979, and is part of the national system of protected areas of Ecuador. Its name is derived from one of the primitive cultures that inhabited the Pacific coast between 1800 and 1000 BC. It covers a large terrestrial and maritime area where a significant biodiversity of flora and fauna lives, due to the presence of the last tropical dry forest in the country, with more than 150 endemic species. In the marine area, it serves as the nesting space for the four species of turtles recorded in Ecuador and mating humpback whales [90].

Figure 2 shows a map of the province of Manabí where Machalilla National Park is located.

Tourist products located within the limits of the PNM include Los Frailes beach, Isla de la Plata and the Agua Blanca community. There are important archaeological sites that document human occupation dating back 5000 years and constitute a special attraction for visiting the archaeological museum that exists in Agua Blanca.

The social situation within the limits of the PNM is not satisfactory. It is common to find small towns with a high degree of vulnerability. The Salaite and Pueblo Nuevo communities are located on the coast, and their essential economic activity is artisanal fishing; the rest are surrounded by mountainous terrain with subsistence based on small agricultural and livestock farms, as is the case of San Isidro, Cerro Mero, Julcuy, Platanales and El Pital. The site known as Guale stands out, where the Agua Blanca tourist facility is located, which manages to achieve a certain level of sustainable development based on the enhancement of its natural and cultural resources from a community organizational base closely linked to the environment in a sustainable manner [54,91].

In the context of Ecuadorian society and its notable multiversity, tourism constitutes a socioeconomic factor representing an alternative for development. It is poised to become a key economic activity based on the use of endogenous resources, capable of replacing the variants of extractive economies that prey on natural resources and pollute the environment. Moreover, tourism has the potential to reduce the poverty and precariousness gap in peripheral locations of major cities, as well as in semi-urban and rural areas.

Among the methods, historical–logical analysis was performed that allowed the examination of tourism development in Ecuador from its beginnings as an economic activity and the emergence of the various modalities of tourism as an alternative for less favored communities. The result allowed us to understand the systematization of the studied models and represented a contribution to the proposed design of the sustainable tourism model in protected areas. This was achieved through the graphic representation of the analysis units comprising it, as well as their argumentation.

The modeling method facilitated the development of the sustainable tourism model in protected areas, enabling the explanation of the features and particularities through an innovative process and the evaluation of experts, aimed at facilitating the improvement of tourist activity by correcting the difficulties that exist in traditional practices, which do not guarantee the sustainability of the tourism sector in the context of protected areas.

This research is based on the deductive method, which made it possible to appreciate the problem related to the lack of a theoretical model of sustainable tourism development in protected areas, capable of carrying out relevant evaluations linked to the demand, supply, governance and management of community tourism in the context of protected areas [92].

Figure 3 presents a diagram of the methodology applied for the research.

The research development facilitated the exploration of general theories related to sustainable tourism management models, their theoretical structure, and the characteristics and management requirements of protected areas. This enabled the definition of the hypothesis and the formulation of conclusions on the topic studied.

The work is analytical, descriptive and explanatory, enabling the analysis of the literature consulted to describe the proposal of the theoretical approach related to the sustainable tourism model in protected areas and explaining its systemic structure within the framework of the interrelationships between the external and internal components and units of analysis. This allowed the integration of the contributions of the qualitative and quantitative analyses in the treatment and processing of the results of the interviews and discussions carried out with the actors of the tourism sector, as well as the numerical data obtained from the results of the surveys carried out with tourism experts. All of this allowed us to delve deeper into the phenomena linked to tourism.

The systematic review of the literature and primary source documents allowed the analysis of several scientific articles, theses, books and primary source documents related to the topic of study from their different conceptual denominations. The selection of documents included a rigorous review of related literature, with special attention paid to publications from 2018 to 2022.

As an instrument, a documentary analysis guide was applied that included origins, concepts and definitions, characteristics, geographical distribution, segmentation and customer profiles, leading countries worldwide and on the American continent, new trends in the tourism sector, and the demands of clients in the new scenario due to the impact of COVID-19, as well as the current economic situation on a global scale.

The analysis of general theories related to the sustainable tourism model in protected areas required consultation of tourism types and modalities, demand, supply, superstructure, infrastructure, the receiving community, governance, and innovative models applied to improve tourism activity in recent years.

An analysis of works theoretically based on tourism modalities and types of tourism was carried out, including the theoretical approach based on the value chain applied to the integration of municipal and extra-municipal value, as well as the value chain, to promote development [93]. The work focuses on the analysis of the economic, environmental, and sociocultural components, supply and demand, and the balance of both indicators and governance for sustainable tourism.

The evaluation process of indicators related to sustainable tourism and competitiveness was analyzed [94]. The systemic approach focused on sociocultural aspects with the objective of placing the visitor at the center of tourist activity, through the structuring of a model made up of six components [95].

The sustainability indicators of tourism in protected areas are based on the thematic scope of sustainable, social, economic, environmental and institutional development. According to the theoretical sense and the obtainment of data for evaluation, they are classified into objective indicators that are quantitative and for which information obtained from the different collection and processing methods is used, and subjective indicators that respond to a qualitative analysis based on information obtained from the opinions and perceptions of the population related to a given situation [96].

To evaluate the sustainability indicators, their classification was analyzed according to the characteristics of the destination, as shown in Figure 4.

The basic indicators make it possible to obtain elements that are key during the monitoring of changes related to the interaction between humans and nature. They correspond to basic data and information that are typically straightforward to obtain.

The complementary indicators serve to complement the basic indicators, allowing for a more comprehensive design. They enable the identification of specific variables tailored to different types of destinations, which may include indicators of specific ecosystems and management indicators of specific sites.

Specific ecosystem indicators are divided into eight different groups according to ecosystem categories, among which is the classification of unique ecological sites, which usually coincide with ecotourism destinations. The management indicators of specific sites are designed by the actors of the tourist destination for their application in specific sites, which, in turn, are subdivided into the following: ecosystems of coastal and mountain areas, wildlife parks, urban ecosystems, cultural heritage, traditional communities and small protection islands. These allow the measurement of the particular attributes of the specific tourist destination and encourage decision-making aimed at the sustainable promotion of activities with an impact on the attributes.

In the analyzed works, there is evident interest in studying the problems of tourism, particularly economic aspects focused on demand, supply and spatial organization. However, this perspective often lacks depth and, in some cases, reflects a vision that transcends the central objective of the functioning of tourism, with a shift towards positions focused on the well-being of man and society with sustainability criteria; nonetheless, the systemic element is only partially analyzed in these works [78].

A comprehensive understanding of governance has not been achieved, nor has the integration of an innovation model to promote continuous improvement through the articulation of a system of internal inter-relationships. This system would involve analyzing the receiving community, the environment, supply and demand together, while balancing of both indicators in a systemic context. Several external components would influence this system, including public–private partnerships, alliance between both sectors, creativity, innovation, the influence of the regulatory framework, the environment and competition. These challenges highlight the need to adapt to new demands in the context of sustainable tourism in a changing world.

The external components of entry into the system include the demand profiles of tourists, which may vary in their preferences and needs for information, material and financial resources, as well as the components of external production, satisfaction of the client and the improvement of living conditions, emphasizing the improvement not only of the enterprise's workers but also of the community that surrounds them.

A structured survey was applied to a non-probabilistic sample of seven experts in the field of tourism to obtain relevant information on the evaluation of the proposed sustainable tourism model in the protected areas and its contribution as a scientific foundation, based on the indicator system used for evaluation. For the analysis of the survey, a Likert-type scale was applied to evaluate the aspects corresponding to the theoretical model and each unit of analysis that comprises the model as a whole, with the support of SPSS version 25.0 (IBM Corporation, Armonk, NY, EE. UU).

For the selection of the non-probabilistic sample, a population of 13 experts was analyzed, of which 7 candidates were selected. As inclusion criteria, it was considered to select the experts who demonstrated the highest values ​​of competence (K), with proven prestige and professionalism recognized in society, having had a teaching or practical employment relationship in nature tourism in protected areas for five years or more and with representativeness of the places of origin. Those who expressed their agreement to participate in the study were considered for inclusion in the study, and experts who did not give their consent to participate were excluded. From the gender perspective, the sample comprised 3 female and 4 male participants who gave their consent to participate in the research.

To assess the experience of the experts, the level of competence was determined using the coefficient k = ½ (kc + ka), where kc represents a measure of the level of knowledge on the topic being investigated and ka is a measure of the sources of knowledge argumentation [97]. This method was developed in [98] to establish acceptance through values greater than 0.8.

To select the experts, the number of experts was calculated, for which equation 1 was applied.

$$\begin{gathered} M=P(1-P)\frac{K}{i2} \\ M=7 \end{gathered}$$

(1)

where:

M→ number of experts;

i→ desired level of precision;

P→ estimated proportion of expert errors;

K→ constant whose value is associated with the chosen confidence level.

For this case, the following values were considered: i=0.10; P=0.01 and K=6.6564

For the evaluation of the sustainable tourism model in protected areas, expert criteria were considered regarding the units of analysis, the assessment of their relevance, feasibility criteria, applicability, possibility of being generalized, relevance, novelty and originality, as well as validity based on its adaptation to the new demands of clients and their new profiles.

The criteria for use included considerations such as the systemic or integrative nature of the model, its ease of understanding and application, its benefits for the actors involved, the inclusion of international standards, the usefulness of structural components and its adaptability to socioeconomic changes that have occurred in the last five years.

The hypothesis test was established for the assessment of the correspondence of the experts' criteria: H0: R1= R2=… Rn. The average ranges of the experts' evaluations are similar to each other. H1: At least one of the average ranges of the experts' evaluations differs from the rest. Critical region: Asymptotic Sigma ≤ 0.05 (5% significance).

Similarly, the analysis of the average ranges was established to determine the differences in evaluations in the aforementioned criteria, referring to the units of analysis, validity and use criteria. This analysis is complemented by the determination of the medians by criterion to ratify their measures of central tendency.

To determine the potential unsatisfied demand, expression 2 was used:

$$Dpi=D-O$$

(2)

where:

Dpi→ unsatisfied potential demand;

D→ demand;

O→ offer.

For the evaluation of the sustainable tourism model in protected areas that is proposed as a scientific result of the research, the elements to be evaluated by the experts were determined through descriptive statistics, which allowed for evaluation of the units of analysis, validity criteria and criteria of use that are represented in the tables and graphs.

In the interest of carrying out validation by experts, an instrument was designed that considers the aforementioned criteria for evaluation through a Likert scale, facilitating a higher level of precision, where 1 means the highest degree of disagreement and 5 means the highest correspondence between the aspects to be evaluated and the model as a whole.

Figure 5 shows the presentation structure of the theoretical model for sustainable tourism in protected areas.

3. Results

3.1. The Sustainable Tourism Model in Protected Areas

From the selection of the experts, we proceeded with the application of the survey and the processing of the information to validate the proposed model. This included examining interrelationships between the units of analysis that constitute the model, as well as evaluating its validity and applicability.

The assessments were conducted by assigning scores on a Likert scale in the survey, where 1 indicated the highest degree of disagreement and 5 indicated the highest degree of agreement. These scores were used to evaluate various aspects related to the theoretical model and each unit of analysis comprising the model as a whole.

Table 1 shows the expert evaluation matrix for each of the units of analysis and their statistical results.

Figure 6 and Figure 7 show evidence of the above by reflecting the mean ranges and medians (with maximum value) of the evaluations given by the experts to each unit of analysis.

Similarly, Table 2 shows the results of the evaluation of the model by the experts according to the validity criteria: feasibility, applicability, possibility of generalization, relevance, validity, novelty and originality.

Similar to the previous analysis, Figure 8 and Figure 9 show the mean ranges and medians corresponding to the validity criteria of the model, starting from the maximum value in all cases when using the median as a measure of central tendency.

Table 3 shows the experts' evaluations regarding the use criteria.

Figure 10 and Figure 11 show the central tendency in favor of maximum ratings in the case of the criteria for using the model that demonstrate its usefulness, where the median once again reaches the maximum value in all cases.

3.2. Synthesis of the Proposed Model

The sustainable tourism model in protected areas is a theoretical framework designed to promote sustainable tourism in these regions. It is proposed for an economic context that envisions a predictable future, grounded in current tourism trends and new demand profiles.

The model of sustainable tourism in protected areas has a synergistic and holistic character by integrating the units of analysis and their dialectical relationship with the environment, which generates a new and superior result, both qualitatively and quantitatively. It has a dynamic and flexible structure that facilitates its adaptation to the processes of change in the different contexts of protected areas. The intrinsic flexibility of the model allows it to assimilate the contributions to sustainable tourism, as well as those of the tourism management systems and models that were consulted during the research. It considers the particularities of tourism in different countries and regions with the possibility of being enriched through the assimilation of variables from the emergence of new situations and the requirements demanded in protected areas. It is easy to apply and interpret for the actors involved, such as researchers, academics and organizations in the sector.

The proposed sustainable tourism model includes the vocabulary of UN Tourism, international, regional and national organizations and their international standards. It responds to the new health demands of clients. It incorporates the contributions of the gender approach, sustainable tourism, resilience, social responsibility, inclusive tourism and local development. It also integrates the Quintuple Helix model as a tool for transdisciplinary and disciplinary analysis of sustainable development and social ecology.

The quintuple helix model encourages and provides sustainable development from the perspective of the potential that each territory has in terms of tourism resources and their attractions. Modeling allows us to analyze its distribution, as well as its advantages and disadvantages [99]. One of the most interesting issues lies in the incorporation of environmental and social dimensions, which undoubtedly guarantees a more comprehensive and complete examination of sustainable tourism management [100].

The quintuple helix consists of a process that encourages attention to the comprehensive development of tourism. It guarantees the development of science, technology, innovation, protection and care of the environment and society. It is a mechanism that facilitates the transfer of knowledge and promotes international interest under different approaches.

Innovation processes in the quintuple helix are described as a set of activities to solve various types of problems through the participation of actors who use their knowledge, interests, habits, behaviors, experiences and knowledge to solve multiple problems [101]. It results in a model that is deployed from the institutional framework, with innovation as a systemic phenomenon that depends on the level of articulation of the organizations. Innovation as an interactive and social phenomenon allows us to qualify its systemic nature.

3.3. Foundation and Justification of the Sustainable Tourism Model in Protected Areas

The foundation and justification of the model is based on its social relevance, due to the generation of positive social impacts and benefits in the communities that are located within the spatial context of the protected areas, with adequate coordination of the actors and participatory governance that takes into consideration perspective, gender, equity and inclusion of people with disabilities.

Its methodological value is given by its versatility, which allows the best experiences of the proposed model to be replicated and generalized in destinations located in the context of protected areas, enabling the evaluation of the units of analysis in close inter-relation and the projection of changes and continuous improvement in the face of new demands derived from the social dynamics of the 21^st century.

The theoretical value of the proposed model is based on the conceptual clarification and integrated theoretical analysis of the units of analysis that comprise it, as well as the variables that affect sustainable tourism within the context of protected areas. The model offers the possibility of updating the theoretical perspectives of tourism, according to the new factors, actors and variables imposed by the current and future scenario as a proposal for change.

The practical value of the model lies in its contextualization to respond effectively to new factors of change. It allows the updating of research, teaching and links with the community as elements of constant revitalization of the relationships between the public and private tourism and productive sectors, higher education institutions and research centers in the interest of continuous improvement.

The economic impact of the model lies in the development perspectives for communities that rely on an endogenous-based model to achieve the elevation of living conditions. It also aims to protect culture and local identity through the application of good practices in sustainable consumption environments and the achievement of adequate governance with the effective participation of local actors with community-based public policies.

For the design of the sustainable tourism model in protected areas, consideration was given to the content of the Sustainable Development Goals outlined in the 2030 Agenda for Sustainable Development, the principles of sustainable tourism proposed by UN Tourism, and the incorporation of the contributions of corporate social responsibility applied to these tourist scenarios [102].

Figure 12 shows the theoretical model of sustainable tourism in protected areas.

The model is explained based on its structural components that allow sustainable tourism in the context of protected areas and their systemic relationships to be studied and interpreted.

The starting point is the challenges posed by sustainable tourism in protected areas to respond to new tourism demands, starting from considering the needs of national and international clients and financial, material and computer resources, especially their satisfaction, through the adequate and regulated use of endogenous potential and respect for the planned environmental regulations. The possibilities of public–private alliances constitute a special opportunity that can influence the dynamism of the system's relationships to promote innovation and continuous improvement.

The functionality of the model is guaranteed through the operation of the seven units of analysis that integrate it in an environment of creativity and innovation, which combines the interests of the regulatory framework established for the environmental protection of protected areas, with the aim of achieving a model for sustainable tourism.

Analysis unit I ensures participatory governance and constitutes the superstructure for the development of sustainable tourism. The objectives, work areas, and the built and natural parts are considered, as are the adjustments and transformations necessary to be made in the time and context of each place in harmony with nature.

Unit of analysis II comprises the local community and is manifested as a group of actors who share a geographical location and the environment in which they reside. In general, community activities respond to a common objective, an identity, culture, language, customs and values, with a very particular worldview of the world that is manifested through respect and defense of nature. It is also called the receiving community or host community and constitutes an essential element of the sustainable tourism system.

Analysis unit III addresses matters related to demand management and the sustainable tourism market. It takes into account the relationships between clients, beneficiaries and their relationship with the offer in the host community, to prioritize endogenous potentialities. It deepens the knowledge and investigation of demand profiles, enabling strategies to be drawn up that allow for satisfaction of the needs and demands of visitors and benefit the community. The key axis in this unit of analysis focuses on the consideration of the tourist and their relationships with the community [103].

Analysis unit IV focuses on the offer for sustainable tourism. It encompasses the range of options available for developing and offering tourism products in the interest of satisfying demand. It includes restaurant services, accommodation, travel agencies, transportation, tourist information and interpretation services of natural and cultural heritage. The availability of environmental services and healthcare, security, existence of parks, recreation areas, and areas for sports, among others, play a determining role. Its key object and center of action is the tourist as a consumer and environmental respect for nature. It includes combined products and services offered to clients interested in their travel and tourist stay [104].

Analysis unit V analyzes the supply–demand balance. It is carried out through calculating the potential or unsatisfied demand based on the quantity of products and services that the market is likely to consume in future years, highlighting that if the calculation conditions prevail, no current destination can be satisfied. Unsatisfied potential demand occurs when the result obtained must have as a requirement that the demand is greater than the supply, which justifies the incursion with new products and services to add values through innovation and achieve certainty that the current supply is sufficient to cover the demand requirements [105,106].

Unit of analysis VI is based on the innovative spirit through the application of the Quintuple Helix model, which enables the analysis of the challenge that sustainable tourism represents in protected areas through the development of causal relationships between the institutional level, the community, public and private companies, the environment, universities and research centers. Its objective is to integrate the approach of the different actors of sustainable tourism to design a comprehensive training process that achieves synergy between all those committed to tourism activity to respond to real learning and training needs, which is capable of generating innovation through the management and transfer of knowledge and guarantees the assimilation of best practices for the sustainability of the model.

Analysis unit VII focuses on evaluation, feedback and proposals for continuous improvement for the development of sustainable tourism in protected areas. The evaluation, control and feedback of the indicators of tourism sustainability [107] are carried out to guarantee the process of continuous improvement of tourism development, which facilitates the assessment and readjustments of the change processes in case contingencies arise, as well as new variables and trends that directly impact sustainable tourism.

Tourism sustainability indicators in protected areas are tools that allow the quantitative and qualitative measurement of the activity and enable the evaluation of the trend in the destination and its impacts on the environment, the host community and the economic resources generated. Its objective is to offer information and quantitative data on the environmental behavior of sustainable tourism activity in protected areas. They are necessary to achieve the protection of natural resources and the preservation of the cultural identity of the communities to maintain the competitiveness of the destination [102].

For the research, the Pressure-State-Response (PSR) model is applied, which shows the relationships that occur between the pressures on the environment, the impacts they cause, and the political responses aimed at achieving a balance between anthropic activities and preservation of the environment.

The PSR model is based on causality management to evaluate the impact of anthropogenic activities that put pressure on the environment and change the quality and quantity parameters of natural resources. Society responds to changes with sectoral and economic policies. The model is organized based on three types of indicators [103]:

a) Pressure indicators expose direct and indirect pressures on the environment;

b) Status indicators show environmental conditions;

c) Response indicators focus on the responses of the different social and institutional agents.

In summary, the sustainable tourism model for protected areas aims to achieve the sustainability of the tourism project and the actors committed to tourism activity in protected areas, as theoretical underpinnings of the model which, when interacting, ensure the generation of quantitatively and qualitatively superior results.

The theoretical foundations of the model are based on coherence with the concept of sustainable tourism, as well as its principles, dimensions and indicators, and incorporates the contributions of the 2030 Agenda and the Sustainable Development Goals, allowing for the transformation of traditional habits of production, energy and consumption for environmentally friendly lifestyles [102].

4. Discussion

The analysis of the results of research carried out in [3,108,109] allowed us to notice that the modalities of nature tourism, rural tourism and community tourism are those that most agree with the proposed model of sustainable tourism in protected areas.

Socio-environmental diagnosis of the protected area will allow for evaluation of the weaknesses and potential for the successful development of the tourist intervention and customer satisfaction, and will enable the application of the measures and the establishment of the environmental protection protocols that are necessary for the development of tourism in the conditions of protected areas, in accordance with the analyses in [110,111,112].

During the research, the basic units of analysis of a theoretical model for sustainable tourism were studied, which can constitute help for the development of tourism activity in the context of the changing socioeconomic and ecological situation of the current world. The usefulness of the model lies in its possibilities of restructuring and adaptation in its application to solve problems, coinciding with the aspects recognized in [113].

During the design of the proposed sustainable tourism model, the intrinsic dependence of the social system in which it is inserted was considered to respond to a context that integrates sustainability, inclusion, social responsibility, resilience and innovation, demonstrating its scientific relevance in correspondence with the aspects declared in [114,115].

The input elements for the development of the proposed sustainable tourism model in protected areas aim to satisfy the needs and preferences of clients, in order to guarantee a unique and unforgettable experience of direct contact with nature and the exchange of enriching cultural experiences.

During the design of the proposed sustainable tourism model, the contributions and considerations of the Plurinational Federation of Community Tourism of Ecuador [116] were useful, which expresses the experiences of indigenous communities throughout the country and constitutes a guide regarding the offering tourist and accommodation services in indigenous, Afro-Ecuadorian, peasant and Montubia communities, which are genuine representatives of the native cultural traditions and the natural heritage of the Country.

In the design of the proposed sustainable tourism model, governance is incorporated as an expression of good government style in a broad sense, consideration of the legal framework, policies and inter-institutional relations as a strategy for the development of tourism that is sustainable and flexible enough to assimilate the changes and transformations that are necessary in accordance with the dynamics of tourism supply and demand.

The participation of the host community plays a key role in the development of the model. It represents support during the provision of tourist services and is an irreplaceable protagonist during the cultural experiences that tourists experience during their stay. Community performance must be considered in the planning and management process, as a direct actor and beneficiary of tourism activity.

Tourists as visitors with their needs and preferences constitute the central element of demand, which is expressed in the calculation of the consumption of certain products and services. The different types of demand must be considered, such as effective or current, latent, potential, deferred and non-demanded, as well as considering the geographical, economic and psychosociological approaches, first considering the potential of the community and the available endogenous resources in accordance with what was analyzed in [103].

As part of the tourism offer, the coordinated performance of the tour operators must be considered for the communication and sale of the specific tourist product and service that the venture can offer in the context of the protected area. It must be kept in mind that community performance constitutes the main tourism operator that can make the proposed model sustainable [84,88,117].

The innovative model of the quintuple helix is based on the relationship between all the units of analysis of the proposed model, which allows the exchange and generation of new knowledge in the interest of producing and guaranteeing the sustainable development of tourism in the context of the protected areas, in accordance with what was analyzed in [118].

The consideration of resilience is another theoretical underpinning of the model, defined as tourism management that is based on and sustained with respect for the environment and cultural exchange. This fosters rewarding experiences with the community, leading to positive transformation of the socioeconomic component of the territory. It ensures better conditions to confront adversities and emerge stronger from them, in line with what was proposed in [119].

5. Conclusions

The deductive method and the development of the methodological framework highlighted the need to design a comprehensive theoretical framework that allows for the development of sustainable tourism in the particular context of protected areas, which ensures visitor satisfaction through rewarding and unforgettable experiences, generates economic benefits for the enterprise and the host community, and fosters the development of agreeable strategies for the respect and protection of nature.

From the bibliographic analysis, it was elucidated that the tourism modality is defined by the specific mode of tourism in relation to others. It refers to the unique aspect that distinguishes a tourism practice based on the preferences of visitors, which implies the need to distinguish the type of sustainable tourism, such as those tourism practices that pursue and promote the satisfaction of visitors' expectations through rewarding experiences, the protection of the environment, the socioeconomic benefit of the host communities, and the respect of the culture and traditions of the territory, without leaving a negative mark for future travelers.

The examination of the general theories presented in research related to tourism demonstrated that the proposed model of sustainable tourism in protected areas is capable of having a comprehensive and holistic synergistic effect on tourist activity through integrating the units of analysis which, in their interaction, generate a superior novel result from a qualitative and quantitative point of view. The flexibility of the model allows for assimilation of the contributions of tourism management systems and models in general. It presents a design that is easy to interpret and apply for the actors involved, as well as for researchers, academics and organizations in the tourism sector.

The comprehensiveness of the proposed model is guaranteed through incorporating different contributions such as the gender approach, sustainable tourism, community resilience, social responsibility and inclusive tourism. As a novel element, the application of the quintuple helix is ​​incorporated as an innovative base, which constitutes a tool for sustainable development and the promotion of social ecology.

The fulfillment of the research’s general objective highlighted the importance of a well-conceived approach to sustainable tourism in protected areas. As with other tourism modalities, it must be reliable and attractive to potential visitors who seek experiential travel. For this, the intervention of experts was required to carry out a fair diagnosis and evaluate the weaknesses and potentialities that ensure the success of the model and the satisfaction of tourists. In addition, methodologies and procedures were applied to allow the results to be compared with other studies.

The units of analysis of the sustainable tourism model in protected areas were presented. They are useful as they enable restructuring and adaptation in their application to resolve contingencies resulting from changing reality. The model and the units of analysis that comprise it were subjected to expert validation, and the results were favorable.

The main limitation of the study is the proliferation of mass tourism projects currently, hindering the fair distribution of benefits; therefore, they do not contribute to an equitable social redistribution of economic benefits. Tourists who seek this type of service where it is not prioritized favor the preservation of the environment, well-being and quality of life of the communities where tourist activity takes place, which aligns with the findings of [120]. In Ecuador, actors focus more on traditional models of mass tourism and underestimate the development of other models such as tourism in protected areas, which is consistent with what was stated in [121].

It is recommended that future studies continue to deepen the practical validation of the proposed sustainable tourism model in protected areas, with the participation of experts with proven academic experience on sustainable tourism, and analyze the socioeconomic benefits linked to the model for host communities.

The development of the research objectives revealed the need to deepen knowledge on sustainable tourism, especially when carried out in protected areas.

The deepening, articulation and development of a theory argued and contrasted in practice can contribute to the development of sustainable tourism through highlighting the natural, historical and cultural wealth of less-favored areas and achieving a better redistribution of the benefits that allows marginality and poverty to be reduced.

Given the versatility of the proposed model, it can provide theoretical insights and methodological experiences that may be applicable not only nationwide, but also in areas with similar characteristics internationally—especially Latin American countries.