Environmental Education for Sustainable Development: A Bibliometric Review of Curriculum Design and Pedagogical Approaches

ABSTRACT


Environmental
Education for Sustainable Development (EESD) aims to raise awareness, develop knowledge, and promote responsible behavior towards the environment and sustainable development. It is an essential tool for achieving the United Nations Sustainable Development Goals (SDGs) and transforming societies towards sustainability [1]. Some key principles of EESD include continuity, inclusiveness, interdisciplinarity, integration, and unity of theory and practice [2]. These principles can be implemented in various educational settings, from early childhood education to higher education institutions [3]- [5].
For younger children, EESD can involve activities that help them understand the importance of reflecting and acting sustainably in favor of the environment [6], [7]. For example, a study explored the experiences of environmental education for 5year-old children at a daycare center [8]. In higher education, EESD can be integrated into curricula and courses, as well as in the work of volunteer organizations and educational environmental activities [2], [7], [9].
In schools, teachers play a crucial role in implementing EESD. Research has shown that critical reflection on their work can give teachers the confidence to adopt more learnercentered pedagogy for EESD [10]. Moreover, teacher preparation for environmental education and ESD in countries like India has evolved over time, with efforts to integrate environmental, social, and economic concerns into the curriculum. To effectively implement EESD, it is essential to develop a coherent national strategy, allocate dedicated budgets for EESD programs, reform existing laws to ensure coherent implementation, and designate focal EESD units at educational institutions [1]. A systemic framework for connecting the SDGs to educational outcomes can also help in developing evaluation tools to monitor and manage progress in transforming societies towards sustainability [11]. In conclusion, Environmental Education for Sustainable Development is a vital approach to promote responsible behavior towards the environment and achieve the United Nations Sustainable Development Goals. By integrating EESD principles into educational practices and curricula, we can foster a more sustainable future for all.
Environmental challenges, such as climate change, biodiversity loss, and resource depletion, have become increasingly prominent in the global discourse . To address  these urgent issues and create a sustainable   future, it is essential to equip individuals with  the knowledge, skills, and attitudes necessary  to make informed and responsible decisions.  Environmental education serves as a crucial  platform  for  fostering  awareness,  understanding, and engagement with  environmental issues, empowering individuals to become active participants in sustainable development.
The concept of environmental education has evolved over the years, moving beyond traditional classroom instruction to encompass a multidisciplinary and holistic approach. As the world faces complex environmental problems, it is crucial to continually review and adapt the curriculum design and pedagogical approaches used in environmental education [7], [12]. This research aims to undertake a comprehensive bibliometric review of the existing literature to shed light on the current state of curriculum design and pedagogical practices within the realm of environmental education for sustainable development. Environmental education can be traced back to the mid-20th century when concerns about the detrimental impact of human activities on the environment started to gain recognition. Early efforts focused on raising awareness and promoting conservation values through nature-based experiences and educational programs.
Over time, environmental education has evolved to encompass a broader scope, integrating principles of sustainability, social justice, and systems thinking [13].

Environmental
Education for Sustainable Development (EESD) is an important approach to address environmental issues and promote sustainable development. While there is no specific bibliometric analysis on EESD, there are several studies that can provide insights into this field.
Analyzed the implementation of environmental education through ESD approaches [14]. The study found that environmental education and ESD share similar approaches, such as interdisciplinary, lifelong learning, and prioritizing local Conducted a bibliometric analysis of student innovativeness in higher education for sustainable development [15]. The study collected 1,531 academic publications from the Web of Science Core Collection database from 2011 to 2021. The analysis identified principal investigators, publications, productive countries or regions, collaborative institutions, research hotspots, and trends related to student innovation for sustainable development.
Analyzed the incorporation of the Sustainable Development Goals (SDGs) in the university context from an environmental education approach [16]. The study found that many university students have prior knowledge of the environment and believe that environmental education is necessary to address environmental issues.
Critical thinking skills of secondarylevel students in environmental education to achieve the SDGs [17]. The study found that students' critical thinking skills on environmental issues were generally poor, with significant differences between male and female students.
Although this study did not specifically focus on bibliometric analysis of EESD, it will provide valuable insights into this field and its relationship with sustainable development.
The United Nations (UN) has recognized the significance of environmental education for sustainable development, emphasizing its role in the 2030 Agenda for Sustainable Development. Goal 4 of the Sustainable Development Goals (SDGs) emphasizes the need to "ensure inclusive and equitable quality education and promote lifelong learning opportunities for all." Within this goal, target 4.7 specifically calls for the incorporation of sustainable development education, including environmental education, into formal and informal learning settings to equip learners with the skills needed for sustainable living. The primary objectives of this research are to conduct a bibliometric review focusing on curriculum design and pedagogical approaches within the context of environmental education for sustainable development.

The Evolution of Environmental Education
Environmental education has undergone significant evolution over the past decades, reflecting the changing understanding of environmental issues and the need for sustainable development. Early environmental education efforts focused primarily on nature-based experiences and promoting environmental conservation values. These initiatives aimed to raise awareness about ecological systems, biodiversity, and the importance of preserving natural habitats. While such programs were instrumental in fostering a connection to nature, they often lacked an interdisciplinary approach to address the complex socio-environmental challenges [18].
In recent years, environmental education has embraced a more holistic and interdisciplinary perspective, recognizing the interconnections between ecological, social, and economic dimensions. This evolution has been driven by the growing recognition of the interdependence between human well-being and the health of the planet. By incorporating principles of sustainability, environmental education now emphasizes the need for equitable and just solutions that promote the well-being of both people and the environment [19]- [22].

Curriculum Design in Environmental Education
Curriculum design plays a pivotal role in shaping the learning experiences and outcomes of environmental education programs. To effectively foster environmental literacy and sustainability-oriented thinking, curriculum designers often adopt interdisciplinary approaches that connect various disciplines, such as science, social studies, and humanities. Integrating sustainability principles across subjects enables students to grasp the complexity of environmental challenges and the interconnectedness of environmental, social, and economic systems [29]- [34].
Outdoor and experiential learning is another widely utilized approach in environmental education. By engaging students in direct interactions with nature and real-world issues, outdoor learning fosters a deeper connection to the environment and promotes a sense of responsibility for its well-being. Experiential learning allows students to apply theoretical knowledge to practical situations, enhancing their problem-solving abilities and environmental decision-making skills [35]- [38].
Additionally, project-based learning has gained popularity as a curriculum design element in environmental education. By working on meaningful projects that address real environmental issues, students become active agents of change, developing critical thinking and collaboration skills while contributing to sustainable solutions [39]- [42].
Furthermore, the integration of local and indigenous knowledge systems into environmental education is being recognized for its cultural relevance and contributions to sustainability. Acknowledging and valuing traditional ecological knowledge enriches the educational experience and strengthens the connection between students and their local ecosystems [18].

METHODS
A systematic literature search will be conducted using multiple academic databases, including Scopus, Web of Science, ERIC, and Google Scholar. The search terms will be carefully selected to encompass various aspects of environmental education for sustainable development, such as "environmental education," "sustainability education," "curriculum design," "pedagogical approaches," "biodiversity conservation," "climate change education," and "sustainable development goals." The inclusion criteria will focus on scholarly articles published between 1961 and 2023 in English, ensuring the inclusion of recent research relevant to the current state of environmental education.
Once the initial literature search is complete, the retrieved articles will be screened for relevance based on their titles, abstracts, and keywords. The selected articles will be systematically reviewed and categorized according to key themes, curriculum design elements, and pedagogical approaches.
To facilitate the bibliometric analysis, VOSviewer, a widely used bibliometric software, will be employed. VOSviewer allows for the visualization of co-citation networks and the identification of bibliometric clusters, thus enabling the detection of prominent themes and influential authors in the field of environmental education for sustainable development.
The data extracted from the selected articles, such as co-citations and bibliographic information, will be used as input for VOSviewer analysis. The software will generate visual representations of the cocitation networks and bibliometric clusters, offering valuable insights into the structure of the research landscape.  The results of the bibliometric review and VOSviewer analysis provide valuable insights into the current state of environmental education research for sustainable development. The identified key themes highlight the pressing issues that require attention in environmental education curricula. Biodiversity conservation, climate change education, sustainable consumption, and social justice underscore the need for a comprehensive and inclusive approach to sustainability education.

Figure 2. Cluster Details
The cluster analysis identified five distinct thematic clusters within the literature on environmental education for sustainable development. Each cluster represents a different aspect of environmental education, focusing on specific themes, topics, and keywords. The clusters provide valuable insights into the diversity and focus areas within the field, allowing educators, policymakers, and researchers to better understand the current state of research and practice in environmental education. Cluster 1, consisting of 9 articles, centers on the critical issue of climate change and its intersection with environmental education. The most frequently occurring keywords, including "climate change", "environmental attitudes", and "environmental behavior", highlight the focus on understanding how environmental education can influence individual attitudes and behaviors related to climate change. The presence of "youth" and "environmental education programs" underscores the importance of targeting youth in environmental education initiatives, as they represent future decision-makers and bear the long-term consequences of climate change. The findings of this cluster suggest that environmental education programs should be designed to effectively address climate change-related issues and promote positive behavior change to mitigate its impacts.
Cluster 2, consisting of 7 articles, discusses the concepts of environmental impact and management. The occurrence of keywords such as "environmental impact", "environmental management" and "sustainable development" indicates a focus on understanding and mitigating the environmental consequences of human activities. This cluster emphasizes the need for education to foster environmental awareness and responsible decision-making in various sectors, including higher education and policy development.
Environmental education programs associated with this cluster should emphasize the importance of sustainable practices and the integration of environmental concerns into management and policy frameworks.
Cluster 3, which consists of 4 articles, emphasizes sustainability education in school settings. Keywords such as "environmental literacy", "outdoor education", and "school" indicate a strong emphasis on incorporating sustainability principles into the formal education system. This cluster highlights the importance of environmental education in fostering environmentally literate citizens from an early age. It emphasizes outdoor learning and experiential learning as effective approaches to connect students with nature and foster a sense of environmental responsibility. Educators can utilize the findings from this cluster to improve sustainability education in schools and empower students to become active participants in sustainable development.
Cluster 4, which consists of 4 articles, centers on the theme of environmental protection and responsible behavior. Keywords such as "environmental issues", "environmental protection", and "responsible behavior" signify a focus on promoting environmentally responsible actions and addressing environmental challenges. This cluster underscores the need for environmental education to empower individuals to act as responsible stewards of the environment. Findings from this cluster can inform the design of environmental education programs that prioritize responsible environmental behavior and advocate for environmental conservation and protection.
Cluster 5, with 3 articles, discusses environmental learning and perspectives. The keywords "environmental learning", "perspective", "place", and "responsible environment" indicate an emphasis on understanding different perspectives and relationships with the environment. This cluster highlights the importance of contextappropriate environmental education that recognizes cultural diversity and local perspectives on environmental issues. Environmental education initiatives aligned with this cluster should be culturally sensitive and inclusive, fostering a sense of responsibility and respect for the environment.
Overall, this cluster analysis provides valuable insights into the diverse themes and topics in environmental education for  Changing learner behavior through environmental education [50] 3163 RA Hart, 2013 Children's participation: The theory and practice of involving young citizens in community development and environmental care [51] 3153 DA Gruenewald, 2003 The best of both worlds: A critical pedagogy of place [52] It is clear that the years 1961 through 2022 are the ones in which the documents relating to the accounting environment are expressly quoted the most. This can be seen by looking at the graph. New information is less likely to be acknowledged, with the exception of works written by authors who have already conducted study in the topic and are quite well-known.  Table 5 presents a comprehensive overview of the most frequent and fewer occurring keywords within the literature on environmental education for sustainable development. The high occurrence of keywords such as "environmental attitude," "sustainable development," "environmental knowledge," "environmental concern," and "environmental education program" underscores their central importance in shaping environmental education practices and research. Meanwhile, the fewer occurrences of keywords like "climate change," "environmental science," "environmental performance," "environmental learning," and "sustainability education" indicate potential areas for further exploration and research. By addressing these themes and gaps, environmental education can be further enhanced to create a more environmentally conscious and sustainable society.

CONCLUSION
The results of the bibliometric review and VOSviewer analysis provide a comprehensive overview of the current state of environmental education for sustainable development. By understanding the key themes, effective practices, and influential contributors, educators, policymakers, and researchers can collectively work towards creating a more sustainable and environmentally conscious future. The findings from this research can inform the design and implementation of environmental education programs that foster environmental literacy, promote responsible environmental behavior, and empower individuals to address environmental challenges with informed decision-making. Additionally, the identified gaps in research can serve as a guide for future investigations and improvements in environmental education practices, ultimately contributing to a more sustainable and resilient society.