UNESCO Global Geoparks 22 Years after Their Creation: Analysis of Scientiﬁc Production

: Geoparks are unique geographical areas whose geological signiﬁcance is worthy of UN-ESCO designation as a Global Geopark. As of 2022, 177 geoparks located in 46 countries have this designation. The aim of this paper is to identify and analyse the worldwide scientiﬁc production published in the Web of Sciences database in the context of Geoparks. The methodology used was bibliometric analysis, which allows for the rigorous exploration and analysis of large volumes of data. To this end, descriptive and relational indicators were obtained for the ﬁeld of study; performance analysis, scientiﬁc mapping, and network analysis. A total of 324 articles were identiﬁed, the ﬁrst of which was from 1999 by Wolfgang Eder, in which he presented the UNESCO initiative on the creation of geoparks as a tool to promote a better understanding of the geological heritage and the rational use of the Earth’s crust; the rest of the articles were written after the programme was launched (2001). Few authors work on the subject continuously, the author with the highest number of publications has six, and most of the authors with a single authorship are transient. The countries with the highest number of publications are China, followed by Spain, Portugal, Brazil and Italy, where scientiﬁc production is concentrated; the high rate of transience indicates that many countries have only one publication. Most publications are concentrated in two journals: geoheritage and geosciences. In the early years (1999–2003), publications were associated with two research areas, geology and palaeontology, and it is in the last ﬁve years (2019–2002) that the areas of knowledge showing interest in the subject have diversiﬁed.


Introduction
UNESCO Global Geoparks (United Nations Educational, Scientific and Cultural Organisation) are unique geographic territories with clearly defined boundaries, featuring remarkable geological heritage and internationally recognised sites that promote the importance of protecting the Earth's geodiversity through the active involvement of local communities [1].These are managed with a holistic concept of "protection, education, research and sustainable development" [2].Two important elements stand out in this concept: territory and community, whose interaction is not always easy to achieve [3].Geoparks must fulfil four fundamental characteristics: (1) they must have a geological heritage of international value, (2) they must be managed by a legal body recognised in the country where they are located, (3) to have visibility as they promote sustainable local development through geotourism, (4) to cooperate with the rest of the geoparks that make up the global network of geoparks [4].Their geological heritage, together with the cultural heritage of the area where they are located, is used to raise awareness of issues of general concern, such as the sustainable use of natural resources, mitigation of the effects of climate change and reduction of risks related to natural disasters.
In short, there are three pillars underpinning the creation and operation of geoparks: geological heritage, geoconservation and local development.The main purposes for which the geoparks were created are (a) the conservation and maintenance of a healthy environment, (b) the promotion of earth science education, (c) the promotion of sustainable economic development at the local level [5][6][7], and (d) the dissemination and promotion of a better understanding of the geological-geomorphological heritage in ecosystems for their rational use [8].The UNESCO Geopark has extraordinary potential in terms of networking and as a driving force for local economies, which, notwithstanding, limits their effect within the boundaries of the property itself [9].
The geopark concept, as it is known today, was conceived and developed in 1996, and in the year 2000, an agreement was signed by four European territories, leading to the creation of the European Geoparks Network (EGN) [10] and initiating UNESCO's work on geoparks.Subsequently, in 2004, the network was extended to non-European territories and renamed the Global Geoparks Network (GGN) at UNESCO headquarters in Paris, with 17 European and 8 Chinese geoparks forming the network.In the same year, the Madonie Declaration, a cooperation agreement between the Division of Earth Sciences of UNESCO and the Global Geoparks Network, was signed [11,12].It was in 2015, specifically on 17 November, that UNESCO's 195 member states ratified the creation of the UNESCO Geosciences and Geoparks Programme, with UNESCO Global Geoparks as a branch of this programme, during the 38th General Conference of this Organisation [2].
There are currently 177 Global Geoparks located in 46 countries; it is worth mentioning that there are 4 Geoparks that are considered transnational as they are located in 2 countries.In 2022, eight designations were approved, which are: Seridó, Brazil; Roads of the Southern Canyons, Brazil; Salpausselkä, Finland; Ries, Germany; Cephalonia-Ithaca, Greece; Mëllerdall, Luxembourg; Buzàu Land, Romania and Platabergens, Sweden [13].Figure 1 shows the number of Geoparks per country; China has the highest number of Geoparks (41), followed by Spain (15) and Italy (11).On the other hand, we find one Geopark in the following countries: Belgium, Chile, Cyprus, Ecuador, Slovakia, Holland, Iran, Luxembourg, Malaysia, Morocco, Nicaragua, Peru, Russia, Serbia, Sweden, Thailand, Tanzania, Turkey, and Uruguay.The four transnational geoparks are shared between Germany and Poland, Austria and Slovenia, Slovakia and Hungary, Ireland and the United Kingdom [4]; it is worth mentioning that in order to identify the number of geoparks per country, the transnational geoparks were counted in the two countries where they are located.
The distribution of Global Geoparks in each continent is uneven, as the growth of new UNESCO Global Geoparks varies from continent to continent, with Europe and Asia having the fastest growth rate.In Europe, the number of new UNESCO Global Geoparks is five to seven per year, while in Asia, including two new UNESCO Global Geoparks in China each year, other countries such as Japan, Vietnam, Korea, and Indonesia are also actively building UNESCO Global Geoparks [14].The geographical distribution of the global geoparks is determined by the voluntary initiatives of many groups of geoheritage scientists and tourism and conservation professionals, as well as by the governmental vision of the urgency of geotourism [15].
Global Geoparks are a figure whose aims include the sustainable development of the territory [16].In this sense, they contribute to the fulfilment of 8 of the 17 UN Sustainable Development Goals, namely: end poverty (Goal 1), quality education (Goal 4), gender equality (Goal 5), decent work and economic growth (Goal 8), sustainable cities and communities (Goal 11), responsible production and consumption (Goal 12), climate action (Goal 13) and partnerships to achieve goals (Goal 17) [4].The main topics addressed in Geoparks are natural resources, geohazards, climate change, education, science, culture, women, sustainable development, local and indigenous knowledge and geoconservation [1].Global Geoparks are a figure whose aims include the sustainable development of territory [16].In this sense, they contribute to the fulfilment of 8 of the 17 UN Sustaina Development Goals, namely: end poverty (Goal 1), quality education (Goal 4), gender equ ity (Goal 5), decent work and economic growth (Goal 8), sustainable cities and communit (Goal 11), responsible production and consumption (Goal 12), climate action (Goal 13) a partnerships to achieve goals (Goal 17) [4].The main topics addressed in Geoparks are n ural resources, geohazards, climate change, education, science, culture, women, sustaina development, local and indigenous knowledge and geoconservation [1].

2023,
Several key factors can be identified to explain the success of geoparks: the appli tion to become a UNESCO Global Geopark is expertise-conducted but emerges from local will, i.e., it is a bottom-up initiative; their management requires community invol ment and the need to work across other disciplines besides Earth Sciences; their evalu tion, nomination, and revalidation is a self-regulated process conducted by members a pointed by the Director-General of UNESCO on the recommendation of GGN and Member States [17].
The context of global geoparks awakened and awakened the interest of the scient community from different scientific areas (Geology, Palaeontology, Geosciences, Ecolo Environmental Sciences, Engineering, Zoology and others), becoming the subject of s eral research papers and publications [18][19][20][21][22][23][24][25][26][27].The aim of this paper is to provide an ov view and analysis of scientific research conducted in the context of UNESCO Global G oparks (that is, scientific research carried out from the different existing scientific are whose field of study is the geoparks, which have clearly defined limits in the UNESC declaration as a UNESCO World Geopark) and indexed in Elsevier's Web of Science d tabase through the use of bibliometric methods (performance analysis, scientific mappi and network analysis) in order to answer the following research questions: Q1: What is the publication trend in the context of the Geopark in terms of evolution ov time and citations (what are the most cited publications in this context?),most product Several key factors can be identified to explain the success of geoparks: the application to become a UNESCO Global Geopark is expertise-conducted but emerges from the local will, i.e., it is a bottom-up initiative; their management requires community involvement and the need to work across other disciplines besides Earth Sciences; their evaluation, nomination, and revalidation is a self-regulated process conducted by members appointed by the Director-General of UNESCO on the recommendation of GGN and of Member States [17].
The context of global geoparks awakened and awakened the interest of the scientific community from different scientific areas (Geology, Palaeontology, Geosciences, Ecology, Environmental Sciences, Engineering, Zoology and others), becoming the subject of several research papers and publications [18][19][20][21][22][23][24][25][26][27].The aim of this paper is to provide an overview and analysis of scientific research conducted in the context of UNESCO Global Geoparks (that is, scientific research carried out from the different existing scientific areas whose field of study is the geoparks, which have clearly defined limits in the UNESCO declaration as a UNESCO World Geopark) and indexed in Elsevier's Web of Science database through the use of bibliometric methods (performance analysis, scientific mapping and network analysis) in order to answer the following research questions: Q1: What is the publication trend in the context of the Geopark in terms of evolution over time and citations (what are the most cited publications in this context?),most productive authors, most concerned countries with publishing in this context, usage counts, and journals that have a higher frequency of articles written in this context?Q2: What areas of research have been identified over time?What is the intellectual structure of research in this context?How has it evolved over the years, and what are the most recent trends, gaps and areas for future research?
In the literature review, two related pieces of research were found.Stoffelen [28], in his research, conducted a systematic and analytical literature review in Scopus as of December 2018 of 326 articles.In turn, Herrera-Franco et al. [14] carried out a bibliometric review of this same area in the Scopus database as of 1 October 2020, identifying 868 records (journal articles, conference papers, book chapters, article reviews and books).In order to complete this general overview of the subject, this research uses one of the main international databases, such as Web of Science as of 17 July 2022, analysing its evolution, trends and intellectual structure.
This paper is structured as follows.First, the context of the study, the UNESCO Global Geoparks, is contextualised, then the methodology used is presented, the bibliometric analysis following the PRISMA method [29] and the search and exclusion criteria are described, as well as the bibliometric indicators that will be used.In the Section 3, the results are detailed, followed by a discussion of the results, showing the differences and similarities with other studies.It ends with the conclusions derived from the research, in which possible lines of research are presented.

Research Methodology
The methodology used to achieve the objectives is the bibliometric analysis.Bibliometrics is a part of scientometrics that, through statistical and mathematical methods, allows the analysis of scientific publications within a specific area or field of knowledge [30], the results of which are used for decision-making [31].Such analyses help to identify useful patterns that are not obvious at first glance regarding the progress of a specific field of knowledge [32].Bibliometric indicators provide insight into the direction of the subject and the impact of publications in the academic, governmental and social context [33].

Database and Phases of Research
In order to identify the bibliographic portfolio, the PRISMA process (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) was followed.Moher et al. [29] allow a systematic review, applying structured methods, to identify, select and critically evaluate relevant research [34].Table 1 presents how the phases of the PRISMA process were developed in this research.The database from which the bibliometric analysis is developed plays a very important role in this type of research [35], and in this research, we chose to search for the bibliographic material in the international database Web of Sciences (WoS).It is currently considered the main database to be used worldwide [36,37] that collects articles published in journals considered to be of high scientific quality and also provides data on citations received, making it highly suitable for bibliometric analysis [38].
The area of study of the research carried out is in the context of geoparks.Data were extracted in Microsoft Excel in CSV format as of 17 July 2022, excluding editorials, books and conference papers, and data was analysed from 1999 to 2022 (until July).The search terms "ALL FIELDS (geopark OR geoparks OR geo-park OR geo-parks)" were used to search for articles in the fields title, abstract or keywords and with the inclusion criteria of the document type, article and language in all languages.A total of 498 articles were identified, and metadata was downloaded, including information about: authors and their affiliations; article title; year of publication; journal, volume and pages; cumulative citation count; usage count; abstract; keywords; the number of references used; research areas in which the work was indexed; among others.Then, following the PRISMA methodology [29], exclusion criteria were applied to refine the data, eliminating duplicate documents or documents with incomplete information for the analysis, and the abstracts were reviewed, or some documents were read in full to ensure the relevance of the document to the subject matter.The final database contains 324 articles, excluding 174.
Finally, the bibliometric indicators to be used were defined, focusing mainly on a performance analysis that investigates the contributions of the research components within which metrics related to publications, metrics related to citations and metrics of citation vs publication ratios were considered [39].Microsoft Excel was used for the statistical analyses, as well as the graphs presented here.VosViewer software was used for word co-occurrence analysis [40].

Publications by Year and Citations
Among the measures for analysing the performance of an area of knowledge, the most prominent is the number of publications and citations per year; the number of publications is an indicator of productivity, while the number of citations is a measure of impact [39].Figure 2 shows the distribution by year of the 324 publications on Global Geoparks.It shows that the most productive year is 2021, with 53 published articles, followed by 2019, with 49 publications and 2018, with 44 publications.Figure 2 also shows the number of citations per year of the above-mentioned publications.The 324 publications have accumulated a total of 2604 citations, and the citation/publication ratio is 8.04.The largest number of citations, 268, are found in 2019 publications.The average annual growth in the number of publications on geoparks is 18.74%, while the average annual growth in citations to date is 18.00%.

Most Cited Publications
The number of citations can be used to identify the most influential publications in a given field of research [39].In a way, citations signal links between publications [41].Table 2 presents the top 10 most cited articles.The article with the highest number of citations is by Farsani et al. [42], with 167 citations, which discusses the role of geoparks in improving the economy of local populations.On the other hand, from the number of citations and the year of publication of the paper, the ACI (annual citation index) can be obtained.It is important to note that although the UNESCO Global Geoparks programme started in 2001, two years earlier, the first article was published by Eder W., entitled "UNESCO GEOPARKS-A new initiative for protection and sustainable development of the Earth's heritage".In this work, the author mentioned the creation of a global network of natural parks with outstanding geological features, an action promoted by UNESCO with the aim of preserving a healthy environment and improving sustainable economic development.Currently, this article has accumulated 56 citations.
Figure 2 shows five time periods in the evolution of publications, each lasting five years.In Period I (1999-2003), three articles were published, which have accumulated 96 citations to date.The research areas of these first papers are geology and palaeontology.The most cited work mentioned above, with 56 citations, is that of Eder, W., which was published in the journal Neues Jahrbuch fur Geologie und Palaontologie-Abhandlungen.In Period II (2004)(2005)(2006)(2007)(2008) Period IV (2014-2018) includes 103 publications and 979 citations.The research areas are geology, geography, environmental science and ecology, social science-other subjects, area studies, science and technology-other subjects, physical geography, archaeology, biodiversity and conservation, geochemistry and geophysics, marine and freshwater biology, mining and mineral processing, water resources, palaeontology, remote sensing, imaging science and photographic technology, public, environmental and occupational health, economics and business, nuclear science and technology, radiology, nuclear medicine and medical imaging, art, chemistry, materials science, spectroscopy.In this period, the paper "Geo-knowledge Management and Geoconservation via Geoparks and Geotourism" by authors Farsani, Neda T.; Coelho, Celeste O. A.; Costa, Carlos M. M.; Amrikazemi, A., published in the journal Geoheritage has the highest number of citations (59).Finally, Period V (2019-2022) is formed by 178 publications that accumulated 551 citations.In this period, the research areas present are: geology, science and technology-other subjects, environmental sciences and ecology, geography, physical geography, social sciences-other subjects, chemistry, engineering, biodiversity and conservation, arts and humanities-other subjects, forestry, area studies, mining and mineral processing, computer science, life sciences and biomedicine-other subjects, materials science, urban studies, zoology, palaeontology, marine and freshwater biology, oceanography, agriculture, water resources, spectroscopy, remote sensing.The paper "Using Tourism Carrying Capacity to Strengthen UNESCO Global Geopark Management in Hong Kong" by authors Guo, Wei; Chung, Shanshan has the highest number of citations, 35; it is published in the journal Geoheritage.

Most Cited Publications
The number of citations can be used to identify the most influential publications in a given field of research [39].In a way, citations signal links between publications [41].Table 2 presents the top 10 most cited articles.The article with the highest number of citations is by Farsani et al. [42], with 167 citations, which discusses the role of geoparks in improving the economy of local populations.On the other hand, from the number of citations and the year of publication of the paper, the ACI (annual citation index) can be obtained.In this case, the paper of Farsani et al. [42] has the first position with an ACI of 15.18, in second position is the paper of Ruban [43] with an ACI of 8.60 and in third position is the paper of Farsani et al. [44] with an ACI of 7.38.

Usage Count
The WoS provides data related to the use of the information: 180 Day Usage Count, and Since 2013 Usage Count, the first data indicate the use of the document in the last 180 days, while the second data indicate the use of the document from 2013 to the date on which the information was consulted.This research work will take into account the second piece of data: Since 2013 Usage Count.The 324 works analysed here have a total of 4025 usage records, and when these data are related to the total number of citations accumulated by the works, a ratio of 0.64 is observed, which indicates that for each use of the works, an average of 0.64 citations are generated (see Table 2).
According to Table 2, the paper entitled "Analysis of the influential factors for changes to land use in China's Xingwen Global Geopark against a tourism development background" written by authors Shui, W. and Xu, G. and published in 2016, it is the paper with the highest usage count [53].This paper presents 109 queries and 36 citations; in this paper, the authors explore the influence of the variables elevation, slope, river system, traffic arteries and central development zone on land use changes in Shihai, the Chinese city where the Xingwen Geopark is located; between 1995 and 2010, they found that relatively more dramatic land use changes are experienced near the Geopark than in its surroundings, driven by the above-mentioned variables as well as by the tourism industry.

Productivity and Impact by Author
This analysis will reveal the most productive researchers in the field, as well as facilitate the search for research collaborations with other universities and countries [39].Table 3 shows the top 10 authors with the highest number of publications on Geoparks.The list is led by author Wu, F. from China with 6 publications, which have accumulated 63 citations and a usage count of 130 at the date of this analysis.Likewise, it is noteworthy to mention that the author Han, J. is ranked 8th with 2 publications, and these publications have added up to 40 citations, which places him as the 2nd author by number of citations, 1st in the TC/TP ratio with a value of 20.0.He also has a usage count of 70, which is also the 2nd highest in the top 10 by authors.It is also observed that the top 10 most productive authors are distributed in 2 countries according to their affiliation: China and Spain (Table 3).Note: R = Ranking; TP = Total publications; TC = Total citation.

Productivity and Impact by Country
As Geoparks are a worldwide programme, it was considered appropriate to develop a country-by-country analysis of production in the field.Figure 3 shows the number of publications per country, with dark colours identifying the countries with the highest number of publications and with light colours those countries with the lowest number of publications.China tops the list with 67 publications, followed by Spain with 34 publications, Portugal with 26, Brazil with 22 and Italy with 20.The rest of the countries have less than 20 publications.It should also be noted that China and Spain rank first and second, respectively, in terms of the number of Geoparks (see Figure 1).number of publications and with light colours those countries with the lowest number of publications.China tops the list with 67 publications, followed by Spain with 34 publications, Portugal with 26, Brazil with 22 and Italy with 20.The rest of the countries have less than 20 publications.It should also be noted that China and Spain rank first and second, respectively, in terms of the number of Geoparks (see Figure 1).
Figure 3 also shows that the United States of America has a presence in Geoparks publications despite not having any Geoparks in its territory.In the opposite case, Peru has a Geopark but still has no presence in terms of publications.Other indicators that were analysed at the country level are the transience index, the collaboration index, the degree of collaboration and the productivity index.The transience index indicates the percentage of countries that have a publication, in this case, 36.21%.The level of collaboration between countries in Geoparks research can be observed through the index and the degree of collaboration; in this case, the index of collaboration is 1.24, which indicates that in total, there is a greater number of authorships than articles, on the other hand, the degree of collaboration is 17.59%, that is, of the 324 publications on the subject, 17.59% of them were written by authors from 2 or more countries.Finally, the productivity index of the countries is 6.78 (number of authorship per country/number of countries).
Continuing with the analysis of countries, Table 4 presents the top 10 countries according to the number of publications, the number of citations accumulated by these publications and the citation/publication ratio.In the first position of the ranking, we observe China with 67 publications and 608 citations, which gives a citation/publication ratio of 9.07; however, in the citation/publication ratio, the highest value is obtained by Portugal with 18.77 points, this is because with 26 publications it has 488 accumulated citations; in the same sense, Russia stands out with a citation/publication ratio of 9.70 (97/10).It is also observed that in the 8th position are 3 countries (Japan, Malaysia and the USA) with 13 publications each; however, there is a difference between them in terms of the number of citations that have accumulated such publications.Thus, the USA stands out from the other 2 countries with 5.85 citations/publication.Other indicators that were analysed at the country level are the transience index, the collaboration index, the degree of collaboration and the productivity index.The transience index indicates the percentage of countries that have a publication, in this case, 36.21%.The level of collaboration between countries in Geoparks research can be observed through the index and the degree of collaboration; in this case, the index of collaboration is 1.24, which indicates that in total, there is a greater number of authorships than articles, on the other hand, the degree of collaboration is 17.59%, that is, of the 324 publications on the subject, 17.59% of them were written by authors from 2 or more countries.Finally, the productivity index of the countries is 6.78 (number of authorship per country/number of countries).
Continuing with the analysis of countries, Table 4 presents the top 10 countries according to the number of publications, the number of citations accumulated by these publications and the citation/publication ratio.In the first position of the ranking, we observe China with 67 publications and 608 citations, which gives a citation/publication ratio of 9.07; however, in the citation/publication ratio, the highest value is obtained by Portugal with 18.77 points, this is because with 26 publications it has 488 accumulated citations; in the same sense, Russia stands out with a citation/publication ratio of 9.70 (97/10).It is also observed that in the 8th position are 3 countries (Japan, Malaysia and the USA) with 13 publications each; however, there is a difference between them in terms of the number of citations that have accumulated such publications.Thus, the USA stands out from the other 2 countries with 5.85 citations/publication.Note: TP = Total publications; TC = Total citations.

Productivity and Impact by Journal
Table 5 lists the nine journals with the highest number of papers on Geoparks (Table 5).These nine journals account for 49.38% of the articles analysed and 53.34% of the citations.The top-ranked journal is Geoheritage, with 80 publications and 734 citations in those publications, which is indexed in the WoS Science Citation Index Expanded (SCIE) in the categories of Geosciences and Multidisciplinary; it is also ranked in quartile 3 according to Journal Citation Report (JCR) and has a Journal Citation Indicator (JCI) of 0.70 as of 2021; it is also the journal with the highest usage count at the time of downloading information.Within the Geoheritage journal, the most outstanding paper in terms of the number of citations is "Geo-knowledge Management and Geoconservation via Geoparks and Geotourism" by authors Farsani, Neda T.; Coelho, Celeste O. A.; Costa, Carlos M. M.; Amrikazemi, Alireza.; Amrikazemi, Alireza; in this paper the role of geoparks in geopark conservation and geoknowledge management was analysed, 25 geopark strategies were analysed (20 in Europe and 3 in Asia: Malaysia, Japan and Iran; 1 in Australia and 1 in South America: Brazil), the results indicate that finding, introducing and establishing geosites are the first steps for the creation of geoparks, as well as involving local communities in geopark conservation and providing educational projects [44].Through the co-occurrence analysis of keywords used by authors, it is possible to identify the central theme of research in a specific field [54,55].Figure 4 shows the cooccurrence map of keywords related to the geoparks field, in which the VosViewer software was configured to maintain a minimum of 2 co-occurrences, finding 22 nodes and 4 clusters.

Co-Occurrence of Words
Through the co-occurrence analysis of keywords used by authors, it is possible to identify the central theme of research in a specific field [54,55].Figure 4 shows the cooccurrence map of keywords related to the geoparks field, in which the VosViewer software was configured to maintain a minimum of 2 co-occurrences, finding 22 nodes and 4 clusters.The first cluster (Geotourism and Education), marked by the blue circles, contains 5 nodes with the topics "geotourism", "geopark", "heritage", "geology", and "education"; the number of occurrences in this cluster was 12.The second cluster (Geoheritage-Geoconservation-Sustainable Development), in red circles, is made up of 5 nodes with the topics of "geoheritage", "geoconservation", "sustainable development", and in a smaller number by "geosite" and "assessment"; the number of occurrences in this cluster was 7. The third cluster (Geotourism-Management) corresponds to the orange nodes, with 5 nodes in the topic of "tourism", "management", "motivation", "landscape", and "national park"; the number of occurrences in this cluster was 4. The fourth cluster (Geoheritage-Protection-Geodiversity), green circles, contains 7 nodes with the topics "geological heritage", "geochemistry", "grain size", "evolution", "protection" and "geodiversity"; the number of occurrences in this cluster is 3. protection", and "geodiversity"; the number of occurrences in this cluster is 3. Finally, the keyword map shown in Figure 4 identifies the The first cluster (Geotourism and Education), marked by the blue circles, contains 5 nodes with the topics "geotourism", "geopark", "heritage", "geology", and "education"; the number of occurrences in this cluster was 12.The second cluster (Geoheritage-Geoconservation-Sustainable Development), in red circles, is made up of 5 nodes with the topics of "geoheritage", "geoconservation", "sustainable development", and in a smaller number by "geosite" and "assessment"; the number of occurrences in this cluster was 7. The third cluster (Geotourism-Management) corresponds to the orange nodes, with 5 nodes in the topic of "tourism", "management", "motivation", "landscape", and "national park"; the number of occurrences in this cluster was 4. The fourth cluster (Geoheritage-Protection-Geodiversity), green circles, contains 7 nodes with the topics "geological heritage", "geochemistry", "grain size", "evolution", "protection" and "geodiversity"; the number of occurrences in this cluster is 3. protection", and "geodiversity"; the number of occurrences in this cluster is 3. Finally, the keyword map shown in Figure 4 identifies the relationship between "geopark", "geotourism", "geoconservation", and "geoheritage" (red and blue clusters) depending on the thickness of the line.

Areas of Research over Time
The information provided by WoS on each article includes the area of research.By analysing these data, it is possible to detect the current trends and lines of research, as well as the evolution they have undergone over the years.In Figure 5, the research areas have been grouped into 5-year periods, and the number of articles for each area has been counted.It should be noted that some articles are associated with more than one research area, but in order to avoid duplication, they were counted only in the first area listed.
The information provided by WoS on each article includes the area of research.By analysing these data, it is possible to detect the current trends and lines of research, as well as the evolution they have undergone over the years.In Figure 5, the research areas have been grouped into 5-year periods, and the number of articles for each area has been counted.It should be noted that some articles are associated with more than one research area, but in order to avoid duplication, they were counted only in the first area listed.
It can be seen that the first works on the subject of Geoparks were only associated with two research areas: Geology and Palaeontology.However, in the last five years, the areas of knowledge that have shown interest in the subject have expanded and diversified.In the period from 2019 to 2022, 25 areas of research were identified, of which Geology stands out for having the largest number of papers (102), and it could also be considered a consolidated area of research in the study of geoparks as it is present in the five periods of analysis and heads the list in all cases in terms of the number of papers.
Other areas that can be observed are the area of Environmental Sciences and Ecology, whose presence appeared in the period of 2004-2008 with 1 paper but has evolved to have 18 papers in the period of 2019-2022; the areas of Geography and Social Sciences-Other Topics appeared for the first time in the period of 2009-2013 with 2 papers each and have maintained their presence in subsequent periods; finally, the area of Science and Technology-Other Topics appeared for the first time in the period of 2014 to 2018 with 3 papers, and by the following period it already had 20 papers.It can be seen that the first works on the subject of Geoparks were only associated with two research areas: Geology and Palaeontology.However, in the last five years, the areas of knowledge that have shown interest in the subject have expanded and diversified.In the period from 2019 to 2022, 25 areas of research were identified, of which Geology stands out for having the largest number of papers (102), and it could also be considered a consolidated area of research in the study of geoparks as it is present in the five periods of analysis and heads the list in all cases in terms of the number of papers.
Other areas that can be observed are the area of Environmental Sciences and Ecology, whose presence appeared in the period of 2004-2008 with 1 paper but has evolved to have 18 papers in the period of 2019-2022; the areas of Geography and Social Sciences-Other Topics appeared for the first time in the period of 2009-2013 with 2 papers each and have maintained their presence in subsequent periods; finally, the area of Science and Technology-Other Topics appeared for the first time in the period of 2014 to 2018 with 3 papers, and by the following period it already had 20 papers.

Summary of Results
Figure 6 summarises the main findings discovered according to the analysis of publications, authors, countries, magazines, and lines of research that were carried out on the subject of Geoparks.

Summary of Results
Figure 6 summarises the main findings discovered according to the analysis of publications, authors, countries, magazines, and lines of research that were carried out on the subject of Geoparks.

Discussion
The results obtained in this research and summarised in Figure 6 can be compared with those obtained in two similar and recent studies.The first research is by Herrera-Franco et al. [24], who mapped academic research on Geoparks in the international database Scopus from Elsevier publishers for the period of 2002-2020 (they included journals, conference papers, book chapters, article reviews and books) and the second research is by Stoffelen [28] who conducted an analytical literature review in the Scopus database for the period of 2002-September 2018.Both identified 524 and 326 journal articles, respectively.
With respect to the number of publications on Geoparks, this research, as well as that carried out by Herrera-Franco et al. [24], showed continuous growth over the years, which makes evident the interest that this global programme has awakened in the scientific community.It should be noted that a difference in this respect is that here a paper written two years before the start of the programme was detected, and it is precisely this paper which makes public UNESCO's initiative to develop a network of natural parks with geological features of relevance.In both works, it can be observed that the first publications are ascribed to the area of Geology.However, in recent years researchers have had the tendency to work from a different scientific area, Social Sciences, considering tourism as a means for the conservation of the geoheritage of these areas and their sustainable development through the development of a geotourism product [1,10,18,19,28].
In the analysis carried out to identify scientific production by country, the results of this research are corroborated by Herrera-Franco et al. [24] when they identify that, in both international databases, WoS and Scopus, China is the country with the highest num-

Discussion
The results obtained in this research and summarised in Figure 6 can be compared with those obtained in two similar and recent studies.The first research is by Herrera-Franco et al. [24], who mapped academic research on Geoparks in the international database Scopus from Elsevier publishers for the period of 2002-2020 (they included journals, conference papers, book chapters, article reviews and books) and the second research is by Stoffelen [28] who conducted an analytical literature review in the Scopus database for the period of 2002-September 2018.Both identified 524 and 326 journal articles, respectively.
With respect to the number of publications on Geoparks, this research, as well as that carried out by Herrera-Franco et al. [24], showed continuous growth over the years, which makes evident the interest that this global programme has awakened in the scientific community.It should be noted that a difference in this respect is that here a paper written two years before the start of the programme was detected, and it is precisely this paper which makes public UNESCO's initiative to develop a network of natural parks with geological features of relevance.In both works, it can be observed that the first publications are ascribed to the area of Geology.However, in recent years researchers have had the tendency to work from a different scientific area, Social Sciences, considering tourism as a means for the conservation of the geoheritage of these areas and their sustainable development through the development of a geotourism product [1,10,18,19,28].
In the analysis carried out to identify scientific production by country, the results of this research are corroborated by Herrera-Franco et al. [24] when they identify that, in both international databases, WoS and Scopus, China is the country with the highest number of publications, 188 in Scopus and 63 in WoS, followed by Indonesia, Italy, Spain, Portugal and Brazil, although in different positions in both databases.The fact that China is the country with the largest number of Geoparks is considered to be what arouses the interest of its scientific community to publish on the subject.It is worth noting that both databases confirm that Portugal, although it is not the country with the highest number of publications, is the one with the highest ratio between total citations and total publications: in WoS, 18.77 with 26 publications and 488 citations and in Scopus with 52 publications and 945 citations 18.17.In WoS, it is followed by Russia and China (the country with the highest number of publications and citations) and in Scopus by the United Kingdom, Australia and the United States.
With regard to the journals in which the documents are published in this research, as in that of Herrera-Franco et al. [24], it is corroborated that most of the documents on the subject have been published in Geoheritage (120 documents in Scopus and 80 in WoS), a journal indexed in both databases belonging to the Springer publishing house.This magazine publishes everything related to aspects of geoheritage and its protection, including its interpretation through education, training, and tourism.In WoS, it is followed by Geoscience and Episodes, and in Scopus by Rendiconti Online Societa Geologica Italiana alongside Episodes.A joint analysis of both investigations allows us to recognise the most relevant documents by number of citations (top 5) in Scopus [42,[56][57][58][59] and in WoS [42][43][44][45][46][47].
Finally, the most relevant section of the analysis refers to the consolidated and emerging areas of study.This research was analysed through the research areas in which WoS classifies the articles and through the study of the co-occurrence of words.Through Cluster 4, several lines were identified, "Geotourism and Education", "Geoheritage-Geoconservation-Sustainable Development", "Geotourism-Management", and "Geoheritage-Protection-Geodiversity".It was also noted that the first works were carried out in the area of Geology, and it is still the area with the highest number of publications.However, currently, research is emerging from 25 areas, especially in Environmental Sciences & Ecology, Geography & Social Sciences and Science & Technology.Specifically, a consolidated line of research is identified in which are grouped all those words in which, mainly descriptive studies on geomorphological heritage, the evaluation and identification of geo-sites, and a set of case studies in which actions aimed at preserving and promoting geoheritage through the development of geotourism are analysed, as well as studies aimed at defining the concept of geotourism are carried out.This line of research was mostly developed in the early stages of scientific publications on the subject, and of course, it continues to develop.A second emerging and incipient line is related to geotourism, and it is understood from different approaches: (1) how to promote the sustainable development of Geoparks through geotourism; (2) how to promote the conservation and protection of geoheritage through geotourism; (3) how geotourism promotes the generation of socio-economic benefits for local communities; (4) how to promote the sustainable regional development of local communities that are integrated into Geoparks; (5) how to promote the sustainable regional development of local communities that are integrated into Geoparks; (6) how to promote the conservation and protection of geoheritage through geotourism; and (7) how to promote the sustainable regional development of local communities that are integrated into Geoparks.These questions are intended to address the three pillars (geological heritage, geoconservation and local development) that underpin, as mentioned in the introduction, the creation and operation of Geoparks.
These findings corroborate the work done by Stoffelen [28] (p.97), who states that "critical analyses of the heritage values of landscapes, the position of local communities, and the processes through which the above socio-economic benefits are to be achieved, remain largely absent in geopark research.This author also states that "(Geo)heritage cannot be decoupled from people's activities and interpretations", "Geoparks are not community-free environments", and "Attention to communities is needed to assess sustainable regional development in geoparks".Therefore, taking into account the analytical review of the literature carried out, which we gather into four groups (geoheritage, geodiversity, and geoconservation descriptions; geo-education and geotourism, sustainable development and geotourism; and other), it is stated that there is a need for "more innovative, interdisci-plinary studies of the role of the community in, and the societal embedding of, geoparks" Stoffelen [28] (p.97).
These results also corroborate the research carried out by Herrera-Franco et al. [24].In their bibliometric analysis, they identified 6 clusters in terms of research areas: (1) Unesco Global Geoparks, (2) geo-heritage-geosite, (3) geo-conservation-geo-morphosite, (4) geodiversity-biodiversity, (5) Geopark-sustainable development, (6) geo-tourism-sustainable tourism.These researchers underline the importance of geotourism "highlighting how Geoparks improve rural communities' economic situations through the conservation of natural heritage and, in turn, favour geoscience education and the development of tourism practices with environmental sustainability" [24] (p.23).These authors state that "geotourism is an integral part of UNESCO Geoparks and is an example of niche marketing, a hidden opportunity that it is in an initial stage commercially" [24] (p.24).

Conclusions
This research work provides an overview of the scientific publications published in journals indexed in the international WoS database owned by the company Clarivate Analytics, in which research carried out in different scientific areas is framed within the framework of the UNESCO Global Geoparks.This work has been conducted with the aim of completing the scientific mapping carried out by other authors, such as Herrera-Franco et al. [18], who, in their research, consider the limitation of considering a single database (Scopus) and propose completing the scientific mapping with other databases, especially WoS, as both are the main international databases.On the other hand, this research allowed us to corroborate the results obtained by these researchers and to provide, together with their research, a complete mapping of the subject under study.
In this sense, this research aims firstly to contribute to the scientific literature on the subject by mapping the research carried out in Geoparks in one of the main international databases (WoS) and thus complementing that carried out by Stoffelen [28] and Herrera-Franco et al. [24] in Scopus.On the other hand, the results offer valuable information to researchers and practitioners; it provides information on the researchers working on this topic, the most important documents in terms of citation and usage counts, the countries of affiliation of the researchers, etc.It was noted that Geoparks are a topic of study of global interest, which has increased significantly in the last decade, and that is not only of interest to those countries that have Geoparks in their territory.Also that their study is not limited to one area of knowledge, but day by day, new areas of knowledge are turning their attention to Geoparks, so the focus of research is changing from descriptive case studies centred on the social importance of geoparks and mostly focused on the study of geomorphological features (geosciences) to studies that consider the interaction between humans and the environment in this field of study.This approach leads to studies from different disciplines.In this context, geotourism linked to UNESCO Geoparks has emerged.
Finally, it was noted that there are few studies that address how Global Geoparks contribute or can contribute to the sustainable development objectives of the territory for which they were created.The Sustainable Development Goals are designed to achieve a sustainable future for humanity and have therefore incorporated current global challenges, including environmental degradation, to which we have consciously and unconsciously contributed.In this sense, Global Geoparks play an important role in the conservation of the planet, firstly because they have a geological heritage that has been recognised and secondly, because that heritage is intended to be used rationally in the promotion of education about the planet, as well as for the economic development of the place, thus representing an honest and humble quest for a life in harmony with Earth.Therefore, future lines of research should be addressed from topics with a multidisciplinary approach, such as natural resources and their use by geotourism, climate change, education, sustainable development, local and indigenous knowledge, geoconservation, studies from a gender perspective; it could be analysed of the types of publications in different countries to find the characteristics of publication types in each country or on each continent, and to determine the dependence between the number of geoparks and the number of publications in a given country or on a given continent; finally, the forces and barriers that motivate the creation of new geoparks and the research around them could be analysed.Funding: This publication has been funded by the Consejería de Economía, Ciencia y Agenda Digital de la Junta de Extremadura and by the European Regional Development Fund of the European Union through the reference grant GR21161.

Land 2023 ,
12, x FOR PEER REVIEW 6 of 18Celeste; Costa, Carlos published in the International Journal of Tourism Research, received the highest number of citations (167).Period IV (2014-2018) includes 103 publications and 979 citations.The research areas are geology, geography, environmental science and ecology, social science-other subjects, area studies, science and technology-other subjects, physical geography, archaeology, biodiversity and conservation, geochemistry and geophysics, marine and freshwater biology, mining and mineral processing, water resources, palaeontology, remote sensing, imaging science and photographic technology, public, environmental and occupational health, economics and business, nuclear science and technology, radiology, nuclear medicine and medical imaging, art, chemistry, materials science, spectroscopy.In this period, the paper "Geo-knowledge Management and Geoconservation via Geoparks and Geotourism" by authors Farsani, Neda T.; Coelho, Celeste O. A.; Costa, Carlos M. M.; Amrikazemi, A., published in the journal Geoheritage has the highest number of citations (59).Finally, Period V (2019-2022) is formed by 178 publications that accumulated 551 citations.In this period, the research areas present are: geology, science and technology-other subjects, environmental sciences and ecology, geography, physical geography, social sciences-other subjects, chemistry, engineering, biodiversity and conservation, arts and humanities-other subjects, forestry, area studies, mining and mineral processing, computer science, life sciences and biomedicine-other subjects, materials science, urban studies, zoology, palaeontology, marine and freshwater biology, oceanography, agriculture, water resources, spectroscopy, remote sensing.The paper "Using Tourism Carrying Capacity to Strengthen UNESCO Global Geopark Management in Hong Kong" by authors Guo, Wei; Chung, Shanshan has the highest number of citations, 35; it is published in the journal Geoheritage.

Figure 2 .
Figure 2. The number of publications and citations per year.Note: Please remember that the information for the year 2022 represents half of the year since the date of consultation and downloading of the information was in July of that year.

Figure 2 .
Figure 2. The number of publications and citations per year.Note: Please remember that the information for the year 2022 represents half of the year since the date of consultation and downloading of the information was in July of that year.

Figure 3 .
Figure 3.The number of publications by country.Source: own elaboration.

Figure 3 .
Figure 3.The number of publications by country.Source: own elaboration.

Figure 3
Figure 3  also shows that the United States of America has a presence in Geoparks publications despite not having any Geoparks in its territory.In the opposite case, Peru has a Geopark but still has no presence in terms of publications.Other indicators that were analysed at the country level are the transience index, the collaboration index, the degree of collaboration and the productivity index.The transience index indicates the percentage of countries that have a publication, in this case, 36.21%.The level of collaboration between countries in Geoparks research can be observed through the index and the degree of collaboration; in this case, the index of collaboration is 1.24, which indicates that in total, there is a greater number of authorships than articles, on the other hand, the degree of collaboration is 17.59%, that is, of the 324 publications on the subject, 17.59% of them were written by authors from 2 or more countries.Finally, the productivity index of the countries is 6.78 (number of authorship per country/number of countries).Continuing with the analysis of countries, Table4presents the top 10 countries according to the number of publications, the number of citations accumulated by these publications and the citation/publication ratio.In the first position of the ranking, we observe China with 67 publications and 608 citations, which gives a citation/publication ratio of 9.07; however, in the citation/publication ratio, the highest value is obtained by Portugal with 18.77 points, this is because with 26 publications it has 488 accumulated citations; in the same sense, Russia stands out with a citation/publication ratio of 9.70 (97/10).It is also observed that in the 8th position are 3 countries (Japan, Malaysia and the USA) with 13 publications each; however, there is a difference between them in terms of the number of citations that have accumulated such publications.Thus, the USA stands out from the other 2 countries with 5.85 citations/publication.

Figure 4 .
Figure 4. Co-occurrence network of the high-frequently used keywords.Source: own elaboration in VosViewer.

Figure 4 .
Figure 4. Co-occurrence network of the high-frequently used keywords.Source: own elaboration in VosViewer.

Figure 5 .
Figure 5. Evolution of research areas.Figure 5. Evolution of research areas.

Figure 5 .
Figure 5. Evolution of research areas.Figure 5. Evolution of research areas.

Author Contributions:
Conceptualization, data gathering, simulations and numerical tests, methodology, formal analysis, investigation, writing-original draft preparation, and writing-review and editing, M.E.P.-R.; J.Á.-G.; M.B.F.-R.and D.J.-I.All authors have read and agreed to the published version of the manuscript.

Table 1 .
Phases of research methodology based on PRISMA.
, 11 articles were published and received 301 citations as of the date of retrieval of the information from the database (July 2022).The research areas of these articles are geology, environmental sciences & ecology, physical geography, thermodynamics, history, and chemistry.The paper with the highest number of citations in this period (97 citations) is Zouros, N., "The European Geoparks Network-Geological heritage protection and local development", published in the journal Episodes.Period III (2009-2013) includes 29 articles with 677 citations.The research areas in which these papers are classified are geology, environmental sciences and ecology, geography, social sciences-other subjects, archaeology, architecture, area studies, arts and humanities-other subjects, water resources, mathematics, art, chemistry, materials science, spectroscopy, science and technology-other subjects.In this period, the paper "Geotourism and Geoparks as Novel Strategies for Socioeconomic" by authors Farsani, Neda Torabi; Coelho, Celeste; Costa, Carlos published in the International Journal of Tourism Research, received the highest number of citations (167).

Table 3 .
Top 10authors by the number of publications.

Table 4 .
Top 10 countries per number of publications.

Table 5 .
Top 9 journals per number of publications.