Notably, the research uncovered that the image of a sustainable destination not only has a direct impact on the propensity to support sustainable tourism initiatives but also an indirect
INTRODUCTION
Sustainable tourism is becoming a key topic in global discussions focused on environmental preservation, cultural heritage protection, and economic development As the tourism sector confronts challenges like climate change and resource depletion, it is increasingly adopting sustainable practices that ensure long-term benefits for destinations Young individuals play a pivotal role in this transition, as their beliefs and actions significantly influence the direction of sustainable tourism Research highlights the intricate ways in which young travelers engage with sustainability initiatives, revealing that their perspectives are shaped by cognitive and emotional factors, personal values, perceived societal impacts, and the narratives presented in sustainability communications.
Kasim and Wickens (2020) identified a strong link between the awareness, attitudes, and opinions of young people and their preference for eco-friendly travel options This highlights the role of youth as a crucial driving force in the tourism sector, particularly in promoting sustainable tourism practices.
Today's young travelers are not only consumers of travel experiences but also champions of environmental sustainability and social equity Their commitment to sustainable tourism is influenced by increased awareness of environmental issues, active participation in global sustainability initiatives, and the pervasive impact of social media (Kasim & Wickens, 2018; Tolkes, 2018) As the tourism industry recovers from the pandemic, understanding the motivations behind young people's support for sustainable tourism is crucial In Vietnam, experts anticipate that sustainable tourism will emerge as a dominant trend post-Covid-19, with younger travelers showing a heightened awareness of their environmental and social footprints A recent Vietnam Report survey revealed that approximately 94% of tourists are willing to pay more for travel services, particularly in food, to promote sustainable tourism practices (Binh, 2023).
Despite growing research, there are still gaps in understanding how young people's environmental knowledge translates into support for sustainable tourism This study seeks to fill these gaps by creating a theoretical framework that combines the Theory of Planned Behavior with insights from environmental psychology and marketing The focus is on exploring the relationships between young people's knowledge, attitudes, beliefs, and intentions regarding sustainable tourism Recognizing the significant potential of youth to support sustainable tourism initiatives, this research emphasizes their role in promoting impactful practices and contributing to environmental preservation through community-based tourism and ecotourism The study specifically targets young individuals in Ho Chi Minh City due to resource limitations.
Analyzing the data, this paper endeavors to answer the following research questions (RQs), guiding the overall study to be conducted:
RQ1: What is the mechanism behind young people's intention to support sustainable tourism in Vietnam?
RQ2: What is the role of environmental knowledge in driving young people's intention to support sustainable tourism in Vietnam?
This research aims to guide industry professionals in developing marketing and communication strategies that resonate with younger demographics while providing policymakers and educators with insights to foster youth engagement in sustainable tourism initiatives By exploring the intentions and influencing factors of youth, the study highlights their crucial role in the evolution of sustainable tourism, offering valuable perspectives for creating a more sustainable and restorative tourism sector.
Chapter 1 explores the significance of sustainable tourism in combating climate change and conserving natural resources, highlighting young individuals as key advocates for sustainability due to their environmental awareness and digital engagement The study specifically investigates the sustainable tourism intentions of young Vietnamese travelers, analyzing the impact of their environmental knowledge on their support for sustainable practices This research aims to fill gaps in understanding how this demographic's awareness translates into sustainable actions, ultimately guiding marketing, policymaking, and educational initiatives toward sustainability.
LITERATURE REVIEW & HYPOTHESES DEVELOPMENT
Sustainable Development and Sustainable Tourism
Sustainable development, a pivotal concept in both developmental and environmental realms, is often synonymous with sustainability as noted by researchers (Alvarado-Herrera et al., 2017; Gore, 2015; Olawumi & Chan, 2018; Sartori et al.,
Sustainable development, as defined by the Brundtland Commission, emphasizes meeting present needs without jeopardizing future generations (Schaefer & Crane, 2005) This article focuses on sustainable tourism, a vital aspect of sustainable development that champions ecological protection, human well-being, intergenerational fairness, and community involvement (Nguyen et al., 2019; WHO, 1998) Although existing research has explored sustainable tourism's links to climate change and demographic factors (Peeters et al., 2024; Romcra and Lc Bigot, 2023; Tseng et al., 2018), there is a notable lack of studies on individual support for sustainable tourism Our research addresses this gap by investigating the intentions of youth to participate in sustainable tourism practices.
Intention to Support Sustainable Tourism
Numerous studies have explored the complexities of individual decision-making, particularly in relation to purchase intentions and consumer behavior (Chen & Wang, 2016) The Theory of Reasoned Action (TRA) and the Theory of Planned Behavior (TPB) emphasize that purchase intentions are influenced by subjective norms, behavioral beliefs, and perceived behavioral control (Costa et al., 2021).
This study defines "Intention to Support Sustainable Tourism" in a manner similar to "Ecotourism Intention," as previously described by Luong (2023) Pham and Khanh (2021) characterize "Ecotourism Intention" as the desire to visit eco-friendly destinations in the near future Therefore, this research interprets the Intention to Support Sustainable Tourism as the willingness to contribute to sustainable tourism development, which emphasizes ecological preservation, human welfare, intergenerational fairness, community involvement, and the fulfillment of both immediate and future tourism needs.
Attitude towards Sustainable Tourism
The Theory of Planned Behavior (TPB) is increasingly applied in sustainable tourism research, positing that an individual's behavioral intentions and perceived control can predict actual behaviors These intentions are shaped by attitudes, subjective norms, and perceived behavioral control, as established by Ajzen (1991) Notably, attitude serves as a key predictor of intention, reflecting an individual's positive or negative evaluation of a behavior, influenced by expected outcomes and their associated value Ajzen and Kruglanski (2019) emphasize that a person's attitude towards a behavior significantly impacts their likelihood of engaging in it Consequently, this paper focuses on "Attitude towards Sustainable Tourism," defined as the positive evaluation of a tourism site when it is recognized as a sustainable destination.
This study explores the influence of Attitude on the Intention to Support Sustainable Tourism, highlighting its interaction with other factors affecting behavioral intentions By defining "Attitude towards Sustainable Tourism" through the lens of "Environmental Attitude," we reference existing research that establishes a positive correlation between environmental attitudes and sustainable behaviors (Policarpo & Aguiar, 2020; Cerri et al., 2018) Our hypothesis suggests that a strong Attitude towards Sustainable Tourism positively impacts the intention to support sustainable tourism initiatives.
Hl Attitude towards Sustainable Tourism enhances individuals9 Intention to Support Sustainable Tourism.
Belief towards Sustainable Tourism
Research indicates that beliefs play a crucial role in shaping human behavior, particularly in the context of sustainable tourism, which is influenced by environmental perspectives (Ajzen & Fishbein, 2000; Line & Hanks, 2016) These environmental beliefs can be categorized into general and specific types, reflecting various underlying attitudes and systems, ranging from concerns about water scarcity to issues related to global warming (Dietz et al., 1998) Additionally, environmental folklore captures prevalent views on the interactions between humans and their environment (Stern, 2000).
The interplay between beliefs and behaviors is influenced by cultural norms, personal values, and environmental context, with habits and social acceptance also playing significant roles While evidence regarding the connection between pro-environmental attitudes and intentions varies, it is evident that specific behaviors and contextual factors impact this relationship In the realm of sustainable tourism, tourists' intentions to engage in sustainable practices are shaped by their environmental beliefs, perceptions of advantages and disadvantages, available alternatives, social norms, and group identity, leading to the formulation of our proposed hypothesis.
H2a Belief towards Sustainable Tourism enhances individuals9 Intention to Support Sustainable Tourism.
Ecotourism, recognized as a sustainable alternative to traditional tourism, significantly enhances environmental awareness and conservation efforts (Chi & Pham, 2022; Hunitie et al., 2022) This suggests that sustainable tourism practices could similarly foster positive attitudes and behaviors towards the environment The relationship between ecotourism and an individual's connection to nature is intricate, influenced by factors such as activity choices, destinations, and personal experiences (Chi & Pham, 2022; Thi Khanh & Phong, 2020) This complexity highlights the necessity for thorough exploration to understand how ecotourism shapes environmental beliefs, forming the basis for our hypothesis.
H2b Belief towards Sustainable Tourism enhances Attitude towards Sustainable Tourism.
Perceived Sustainable Destination Image
Academic research has identified three key components of destination image: cognitive, affective, and conative aspects The significance of destination image in influencing consumer preferences for products, services, and locations is well-documented, prompting ongoing research in international marketing and tourism Studies have shown that both cognitive and emotional perceptions play a crucial role in fostering tourist loyalty.
This study expands the concept of destination image specifically for ecotourism, building on existing research Findings from Chen and Tsai (2007) indicate that favorable perceptions of a region increase the likelihood of visiting ecotourism sites Similarly, Chiu et al (2014a) demonstrate that the appealing image of ecotourism significantly impacts tourists' decisions to travel Additionally, the influence of tourists' environmental values and beliefs on their perceptions of ecotourism destinations is crucial (Kotler et al., 2021) This underscores the necessity for a comprehensive exploration of how eco-destination images affect ecotourism intentions, emphasizing the need for an extensive literature review.
H3 Perceived Sustainable Destination Image enhances individuals’ Intention to Support Sustainable Tourism.
Tourists' environmental attitudes towards eco-destinations are shaped by their motivations and values, as highlighted by Chi and Pham (2022) The role of sustainable tourism in influencing these attitudes and behaviors is essential (Bilynets & Knezevic Cvelbar, 2022) Additionally, a tourist's prior environmental views and experiences can alter the impact of a sustainable destination's image on their environmental concerns (Chi et al., 2018) Despite some limitations, research indicates a link between perceptions of sustainable destinations and environmentally conscious behaviors Notably, studies by Pham and Khanh (2021) and Chiu et al (2014b) reveal that the image of eco-destinations significantly influences Vietnamese tourists' environmental concerns and positively affects the ecological attitudes and behaviors of tourists in Taiwan Based on these findings, this paper proposes the following hypothesis:
H4a Perceived Sustainable Destination Image enhances individuals’ Attitude towards Sustainable Tourism.
H4b Perceived Sustainable Destination Image enhances individuals’ Belief towards Sustainable Tourism.
This study highlights that the perceived image of a sustainable destination significantly impacts tourists' intentions, both directly and indirectly through their attitudes towards sustainable tourism A destination's image shapes expectations about engagement outcomes, suggesting that if tourists view a destination as sustainably managed, they are likely to develop positive attitudes towards sustainable tourism These favorable attitudes can enhance their support for sustainable practices Additionally, tourists' environmental values and beliefs play a crucial role in shaping their perceptions and attitudes; when aligned with a destination's sustainability efforts, these values lead to a more positive attitude towards sustainable tourism, ultimately increasing their intention to support such initiatives This aligns with the Theory of Planned Behavior (TPB), which emphasizes that internal attitudes are vital in forming intentions, despite external influences.
H5 The influence of Perceived Sustainable Destination Image on the Intention to Support Sustainable Tourism is positively mediated by Attitude towards Sustainable Tourism.
The image of a sustainable destination significantly influences tourists' beliefs and intentions to support sustainable tourism practices While the connection between attitudes and intentions is well-established, the intricate role of beliefs in sustainable tourism warrants further exploration This aligns with broader academic discussions indicating that perceptions of a destination's sustainability are crucial in fostering the intention to adopt sustainable practices.
H6 The influence of Perceived Sustainable Destination Image on the Intention to Support Sustainable Tourism is positively mediated by Belief towards Sustainable Tourism.
Given the interplay of our proposed H5 and H6, we posit that:
H7 There is a serial mediating role by Belief towards Sustainable Tourism and Attitude towards Sustainable Tourism in the effect of Perceived Sustainable Destination Image on Intention to Support Sustainable Tourism.
Environmental knowledge
Recent research indicates a significant connection between environmental knowledge and intentions for green purchases, contrasting earlier findings by Levine and Strube (2012) Our study builds on the work of Nekmahmud et al (2022) and posits that environmental knowledge positively moderates the relationship between attitudes toward the environment and intentions for sustainable purchases, particularly in eco-friendly tourism choices Evidence also highlights a growing preference for green hotels among travelers (Wang et al.).
Environmental knowledge plays a crucial role in enhancing the connection between positive attitudes towards sustainable tourism and the intention to engage in sustainable purchasing behaviors This relationship suggests that individuals who are more informed about environmental issues are more likely to make sustainable choices, supporting our proposed hypothesis.
Environmental knowledge plays a crucial role in influencing the relationship between attitudes towards sustainable tourism and the intention to support it Specifically, increased levels of environmental knowledge enhance the positive effects of favorable attitudes on the intention to engage in sustainable tourism practices Conversely, lower levels of knowledge may diminish these effects, highlighting the importance of education in promoting sustainable tourism initiatives.
Chapter 2 discusses sustainable development and tourism’s relevance, emphasizing young people's impact through their sustainability attitudes, beliefs, and intentions It examines decision-making in sustainable tourism using the Theory of Planned Behavior and aims to address how young people's environmental awareness leads to sustainable practice support By proposing hypotheses around attitudes, beliefs, destination images, and environmental knowledge, the study seeks to boost youth engagement in sustainable tourism.
RESEARCH METHODS
Measurements SCALES
This research utilized adapted measurement tools from validated scales, structured on a five-point Likert scale ranging from 1 (strongly disagree) to 5 (strongly agree) Specifically, "Attitude towards Sustainable Tourism" was assessed using five items from Huang & Hsu (2009) and Kim & Stepchenkova (2020), while "Belief towards Sustainable Tourism" was evaluated through four items based on Dunlap et al (2000) and Li et al (2021) The "Perceived Sustainable Destination Image" included four items from Chi and Pham (2022), Chiu et al (2014b), and Sharma and Nayak (2018), and "Environmental Knowledge" was measured with four items from Mohaidin et al (2017) Lastly, "Intention to Support Sustainable Tourism" was gauged using a four-item scale from Huang & Liu (2017), Hultman et al (2015), and Pham & Khanh (2021), culminating in a total of twenty-one items across five constructs.
The measures were originally created in English and translated into Vietnamese using Brislin's (1986) methodology to maintain linguistic accuracy Preliminary testing included a pretest with eight participants and a pilot study involving forty-five participants to ensure the instrument's validity and reliability (Hulland et al., 2018) This initial phase revealed some ambiguous items, which were revised prior to finalizing the questionnaire for the survey.
Research sample, SURVEY procedure and DATA analyzing technique
Young people today possess the ability to utilize advanced technology and social media to promote sustainable tourism, enhancing community awareness and behavior This demographic effectively supports environmental preservation by sharing experiences related to community-based tourism and ecotourism, fostering deeper connections with nature Additionally, their participation in volunteer activities provides valuable experiential learning opportunities while allowing them to contribute meaningfully to local communities In December 2023, an online survey was conducted in Ho Chi Minh City, Vietnam, gathering responses from 403 young individuals, of which 394 (97.8%) were deemed valid for analysis after data screening.
The demographic analysis revealed that 62.7% of participants were female and 32.3% were male, primarily born between 1997 and 2012 The age distribution included 3.6% aged 15-17, 52.3% aged 18-22, and 44.1% aged 23-26 Notably, 96.4% of respondents held a bachelor's degree, while only 3.6% had a high school education or lower The survey focused on individuals aged 15 and older, as this age group is expected to have a more independent perspective and a better understanding of tourism-related issues compared to younger participants, who tend to rely more on their families.
Following the elimination of random responses during the initial screening, the remaining data were analyzed using the Partial Least Squares - Structural Equation Modeling (PLS-SEM) technique This method is particularly effective for formative constructs, as it accommodates smaller sample sizes and less stringent residual distributions (Chin, 1998) Consequently, PLS-SEM is well-suited for research that emphasizes predictive behavior rather than solely theoretical validation.
Chapter 3 describes the research methodology, including the adaptation of measurement scales from established sources to evaluate constructs associated with sustainable tourism via a five-point Likert scale It entailed the translation of these measures into Vietnamese, preliminary reliability testing, and the execution of an online survey aimed at young individuals in Ho Chi Minh City The chapter also explores the demographic composition of the survey participants and employs Partial Least Squares Structural Equation Modeling (PLS-SEM) for data analysis, underscoring the emphasis on the capacity of young people to endorse sustainable tourism initiatives through digital participation and community engagement.
RESEARCH RESULTS
Common bias method
The use of respondent-driven sampling in this study may have caused an overestimation of structural relationships and common method bias (CMB), as noted by Duong & Ha (2021) To address this, the research employed specific CMB tests, including Harman's single-factor test for exploratory factor analysis (EFA), which revealed that a single factor accounted for only 43.730% of the variance, below the 50% threshold indicative of CMB (Cooper et al., 2020) Additionally, the collinearity assessment showed variance inflation factor (VIF) values ranging from 1.318 to 3.143, all below the critical value of 3.3, indicating that CMB did not significantly impact the study's results (Hair et al., 2021).
Measurement model
During the reliability testing phase, an analysis of factor loadings was conducted, where high-quality observed variables must achieve a factor loading of 0.708 or higher Additionally, to ensure acceptable reliability, metrics such as composite reliability (CR), rho_A, and Cronbach's alpha need to exceed the 0.7 threshold (Hair et al., 2021) For convergent validity, it is essential that the average variance extracted (AVE) for each construct surpasses the 0.50 mark (Chin, 1998).
Table 1 Construct Reliability and Validity
Construct / Items Mean SD Loading VIF
Attitude towards Sustainable Tourism (AT)
ATI: I would find site X enjoyable in case it became a 3.985 0.840 0.669(D) 1.318 sustainable destination.
AT2: I would have a favorable attitude towards site X in case 3.561 0.973 0.863 2.902 it became a sustainable destination.
AT3: Site X as a sustainable destination would be fun and 3.528 0.935 0.855 2.643 exciting for me.
AT4: I would find site X to be a pleasant experience in case it 3.591 0.984 0.881 3.143 became a sustainable destination.
AT5: It would be a positive experience that leaves me feeling 3.589 1.063 0.856 2.857 fulfilled and satisfied in case site X became a sustainable destination.
Belief towards Sustainable Tourism (BE)
Cronbach: 0.922; CR = 0.922; rho_A = 0.945; AVE = 0.811BE1: If site X tourism continues on its present course, this 3.784 0.847 0.904 3.191 destination will soon experience a major catastrophe.
Construct / Items Mean SD Loading VIF
BE2: When site X tourism interferes with indigenous nature, it often produces disastrous results.
BE3: The balance of nature and tourism development in site
X is very delicate and easily upset.
BE4: Despite tourism operators ’ special care, site X is still subject to the laws of nature.
Perceived Sustainable Destination Image (DI)
Dll: I think a sustainable destination is one that enjoys political stability, ensuring tourists' safe and secure trips.
DI2: I think a sustainable destination is one that is breathtakingly beautiful, making it a must-visit destination.
DI3: 1 think a sustainable destination is one that has an excellent reputation as an eco-friendly destination among travelers.
DI4: 1 think a sustainable destination is one where the natural environment remains unpolluted and unspoiled, offering a unique and authentic experience to visitors.
Intention to support sustainable tourism (IN)
INI: If site X becomes a sustainable destination, I would prioritize choosing it in my travels.
IN2: 1 plan to visit a sustainable destination like site X in the near future.
IN3: I carefully select sustainable tours that align with my values and beliefs.
IN4: I strongly believe that sustainable tourism is the responsible and sustainable way to travel.
Construct / Items Mean SD Loading VIF
KL1: Tourism can help lo raise awareness of environmental concerns.
KL2: Tourism can increase negative impacts on the local environment if exploited wrongly and/or ineffectively.
KL3: Tourism can encourage local governments to restore historical buildings.
KL4: Tourist spending benefits all citizens in the community, especially those living at the site.
Note: SD - Standard Deviation; VIF - Variance Inflation Factor; CR - Composite Reliability; AVE - Average
Variance Extracted; D - Deleted (low quality)
The research utilized a 5-point Likert scale, yielding mean scores between 3.145 and 3.985, indicating a general agreement among participants with the statements, though not strongly The standard deviations, ranging from 0.740 to 1.063, reflect a moderate diversity in responses, highlighting varied opinions without significant polarization As shown in Table 1, factor loadings for item quality varied from 0.811 to 0.933, with the exception of one item, ATI, which was below the 0.708 quality assurance threshold Additionally, metrics such as composite reliability (CR), Cronbach's alpha, rho_A, and average variance extracted (AVE) all satisfied the established acceptability criteria, confirming the dataset's reliability for further analysis.
Table 2 Assessments of the Discriminant Validity
AT BE DI IN KL
AT BE DI IN KL
Note: AT - Attitude towards Sustainable Tourism; BE - Belief towards Sustainable Tourism; DI -
Perceived Sustainable Destination Image; KL - Environmental Knowledge; IN - Intention to Support
This study assessed discriminant validity using the Heterotrait-Monotrait (HTMT) ratio of correlations method, establishing a cut-off point of 0.85 to ensure the distinctiveness of latent variable pairs As shown in Table 2, the discriminant values for each construct surpassed the inter-construct correlations, with all HTMT ratios ranging from 0.204 to 0.666, well below the 0.85 threshold This outcome confirms strong discriminant validity within the study, further supported by the 95% Confidence Intervals for all correlations, which excluded the value of 1.
1, verifying that each construct is significantly distinct from the others, ensuring the robustness of the discriminant validity assessment.
Structural model
The study evaluated proposed hypotheses by analyzing the statistical significance of path coefficients at a 5% significance level The impact of independent variables on dependent variables was assessed using the coefficient of determination (R2) and effect size (f2) According to Cohen (2013), f2 values indicate varying levels of impact: less than 0.02 signifies negligible impact, 0.02 to less than 0.15 suggests a small impact, 0.15 to less than 0.35 indicates a moderate impact, and 0.35 or higher reflects a large impact.
Table 3 Hypotheses Testing Results (PLS-SEM)
Note: S.E - Standard Error; CI - Confidence Interval; AT - Attitude towards Sustainable Tourism; BE -
Belief towards Sustainable Tourism; DI - Perceived Sustainable Destination Image; KL - Environmental
Knowledge; IN - Intention to Support Sustainable Tourism; ***: p < 0.001
The structural model demonstrated substantial explanatory power, accounting for 55.3% of the variance in the Intention to Support Sustainable Tourism, 31.2% in Attitude towards Sustainable Tourism, and 34.7% in Belief towards Sustainable Tourism These findings provide strong validation for the research model Additionally, the model's predictive capacity was assessed using the PLSpredict method, revealing Q2 values of 0.409 for Intention to Support Sustainable Tourism, 0.254 for Attitude towards Sustainable Tourism, and 0.343 for Belief towards Sustainable Tourism, all indicating robust predictive validity.
The analysis revealed a positive influence of both Attitude and Belief towards Sustainable Tourism on the Intention to Support Sustainable Tourism, with significant statistical values (Attitude: p = 0.302, p < 0.001; Belief: p = 0.233, p < 0.001) Furthermore, the Perceived Sustainable Destination Image also contributed positively (p = 0.241, p < 0.001) These findings support hypotheses Hl, H2a, and H3 Additionally, it was determined that Belief towards Sustainable Tourism positively impacts Attitude towards Sustainable Tourism.
Sustainable Destination Image, with coefficients p = 0.296, p = 0.083 and p = 0.334, f2
= 0.106, respectively, supporting H2b and H4a Finally, Perceived Sustainable Destination Image positively impacts Belief towards Sustainable Tourism (p = 0.590, p
Figure 2 Visualization of Moderating effect of Environmental Knowledge
The study reveals that Environmental Knowledge negatively moderates the relationship between Attitude towards Sustainable Tourism and the Intention to Support Sustainable Tourism, indicated by a coefficient of p = -0.126 (p < 0.001) and an effect size of f2 = 0.034 This highlights the importance of hypothesis H8, as the analysis shows that lower levels of Environmental Knowledge correspond to a more pronounced increase in the intention to support sustainable tourism as positive attitudes strengthen Conversely, this effect diminishes with higher Environmental Knowledge, indicating a complex interaction between knowledge and attitude in promoting sustainable tourism intentions.
Table 4 Mediating Effects Testing Results
Indirect Effect Predictor Mediator(s) Outcome - LLCI ULCI
The study explores the relationships among various factors influencing sustainable tourism, including the perceived sustainable destination image (DI), attitudes towards sustainable tourism (AT), beliefs about sustainable tourism (BE), and intentions to support sustainable tourism (IN) It employs serial mediation analysis to reveal how these elements interact, with findings indicating significant relationships (p < 0.001) between them, supported by lower-level confidence intervals (LLCI) and upper-level confidence intervals (ULCI).
Table 4 confirms that all tested mediating effects hold statistical significance
The Perceived Sustainable Destination Image significantly influences the Intention to Support Sustainable Tourism through various mediation pathways Firstly, it directly impacts the Attitude towards Sustainable Tourism (path 1) Secondly, it affects the Belief towards Sustainable Tourism (path 2) Lastly, a serial mediation involving both Attitude and Belief towards Sustainable Tourism (path 3) is observed, although this pathway demonstrates a slightly weaker effect (Pseriai = 0.053; p < 0.001; 95% CI = [0.028; 0.082]) compared to the direct mediation effect of path 1 (p = 0.101; p < 0.001; 95% CI).
The findings provide strong statistical support for the significance of hypotheses H5 and H6, which relate to the mediation effects of Attitude and Belief towards Sustainable Tourism, respectively Additionally, the results validate the serial mediating effect outlined in hypothesis H7, highlighting the interconnectedness of these factors in promoting sustainable tourism practices.
Table 5 Conditional indirect effects of Perceived Sustainable Destination Image on
Intention to Support Sustainable Tourism
95% CI Predictor Mediator Moderator level Effect -
M + 1 SD 0.209 *** 0.120 0.298 iTcdk'ior Mediator Moderator level Effect
Note: LLCI - Lower-level confidence interval; ULCI - upper-level confidence interval; M - Mean; SD - Standard deviation; DI - Perceived Sustainable Destination Image; AT - Attitude towards Sustainable
Tourism; BE - Belief towards Sustainable Tourism; IN Intention to Support Sustainable Tourism; ***: p < 0.001; *: p < 0.05; serial mediation
Table 5 indicates that the indirect effect of Perceived Sustainable Destination
The impact of environmental knowledge on the intention to support sustainable tourism varies significantly, with a stronger influence observed at lower levels of knowledge As environmental knowledge increases, this effect diminishes, as illustrated in Figure 3 The analysis indicates that at a consistent moderator level (e.g., M - 1 SD), the indirect effect is most pronounced through the mediation of belief in sustainable tourism (p = 0.413), followed closely by attitude towards sustainable tourism (p = 0.403), while serial mediation shows the weakest effect (p = 0.291) This suggests that belief in sustainable tourism plays a crucial role in shaping intentions within this moderated mediation framework.
The study found that participants with lower Environmental Knowledge demonstrated a significantly stronger indirect effect on attitudes towards Sustainable Tourism (P = 0.403; p < 0.001; 95% CI = [0.323; 0.483]) compared to those with average (M) Environmental Knowledge (P = 0.306; p < 0.001; 95% CI = [0.235; 0.376]) and higher levels (M + 1SD) (P = 0.209; p < 0.001; 95% CI).
= [0.120; 0.298]) The Johnson - Neyman technique indicated that significant moderated mediation occurs when Environmental Knowledge (KL1) falls below 4.953, with the majority of cases (96.701%) below this value.
The study found that for individuals with lower Environmental Knowledge (M - 1SD), the indirect effect of Belief on Sustainable Tourism was significantly stronger (p = 0.413; p < 0.001; 95% CI = [10.326; 0.500]) compared to those with higher levels of knowledge (M) (p = 0.282; p < 0.001; 95% CI = [0.204; 0.360]) and even higher levels (M + 1SD) (p = 0.151; p < 0.01; 95% CI = [0.056; 0.246]) The Johnson-Neyman technique revealed that significant moderated mediation occurs when Environmental Knowledge (KL2) falls below 4.472, affecting 91.117% of the cases studied.
Figure 3 Visualization of Conditional effect of Perceived Sustainable Destination
Image (Serial Mediation: Belief towards Sustainable Tourism - Attitude)
Level of Moderator: Environmental Knowledge
The study revealed a notable indirect effect of Belief towards Sustainable Tourism and Altitude among individuals with lower Environmental Knowledge (M - 1SD), with an effect size of 0.291 (p < 0.001; 95% CI = [0.186; 0.396]) This effect was more pronounced than in those with average Environmental Knowledge (p = 0.212; p < 0.001; 95% CI = [0.136; 0.288]) and higher levels (M + 1SD) (p = 0.133; p < 0.01; 95% CI = [0.027; 0.239]) The Johnson-Neyman technique indicated that significant moderated mediation occurs when Environmental Knowledge is below 4.355, affecting 91.117% of cases, thereby highlighting the importance of Environmental Knowledge in the mediation effect within the range of [1; 4.355).
Chapter 4 shows the research results, highlighting methods to counteract common method bias and verify the measurement model's validity It explores the analysis of the structural model, focusing on how beliefs, attitudes, destination image, and environmental knowledge relate to young Vietnamese individuals' support for sustainable tourism Results show positive effects of attitudes and beliefs on support intentions, moderated by environmental knowledge The study confirms hypotheses, showing the nuanced factors influencing youth support for sustainable tourism.
DISCUSSION
General discussion and managerial implications
The validation of Hypotheses Hl, H2a, and H3 reinforces previous research, demonstrating the critical role of Attitude towards Sustainable Tourism, Belief in Sustainable Tourism, and Perceived Sustainable Destination Image in promoting support for sustainable tourism initiatives, as evidenced by Luong's findings.
Recent studies, including those by Li et al (2021) and Chi and Pham (2022), highlight the growing focus on sustainability in tourism decision-making This trend emphasizes the need for tourism strategies that align with sustainable goals and encourage responsible practices The positive relationship between beliefs about sustainable tourism and attitudes towards it suggests that ingrained environmental beliefs play a crucial role in shaping tourists' perspectives Therefore, targeting these beliefs in sustainability initiatives and marketing is essential for promoting responsible tourism.
Research supports a positive relationship between Perceived Sustainable Destination Image and attitudes towards sustainable tourism, indicating that favorable views of a destination's sustainability efforts can influence tourists to make more eco-friendly travel choices This highlights the importance of tourism authorities and marketers in promoting a destination's sustainable image as a vital strategy for encouraging sustainable tourism Additionally, studies validate the positive connection between Perceived Sustainable Destination Image and beliefs about sustainable tourism, reinforcing the significance of these perceptions in shaping tourist behavior.
A study from 2021 reveals that the portrayal of destinations regarding sustainability greatly affects tourists' perceptions of sustainable tourism This underscores the critical role of destination branding focused on sustainability, which can effectively shape positive beliefs and attitudes among travelers.
The research confirms that attitude towards sustainable tourism serves as a mediator between perceived sustainable destination image and the intention to support sustainable tourism This mediation implies that a destination's sustainable image can enhance tourists' attitudes, subsequently encouraging them to adopt sustainable practices, consistent with the Theory of Planned Behavior (Ajzen).
The study indicates that belief in sustainable tourism serves as a mediator between the perceived sustainable destination image and the intention to support sustainable tourism This suggests that tourists' perceptions of a destination's sustainability significantly shape their beliefs, ultimately influencing their willingness to support sustainable tourism initiatives.
H7 reveal a serial mediation involving Belief towards Sustainable Tourism and
The sustainable image of a destination significantly shapes tourists' beliefs about sustainability, which in turn influences their attitudes and ultimately affects their intention to support sustainable tourism This intricate mediation process highlights the psychological progression from perception to intention in the decision-making process related to sustainable tourism.
The unexpected finding regarding H8 reveals that Environmental Knowledge negatively moderates the relationship between Attitude towards Sustainable Tourism and Intention to Support Sustainable Tourism This indicates that individuals with higher environmental knowledge may evaluate their support for sustainable tourism through a more critical lens, rather than relying solely on positive attitudes, as noted by Mowforth and Munt (2015) This complexity in decision-making underscores the importance of adopting a multi-dimensional approach to effectively promote sustainable tourism practices.
Theoretical contributions
This study highlights the critical role of environmental knowledge in moderating the relationship between key factors and the intention to support sustainable tourism, utilizing the Theory of Planned Behavior (TPB) to analyze Vietnamese tourists' psychological and behavioral responses By expanding the application of TPB, the research emphasizes the predictors and consequences of attitudes towards sustainable tourism and reveals how cognitive processes influence sustainable behaviors A significant finding indicates that environmental knowledge can diminish the impact of attitudes and beliefs on intentions related to sustainable tourism, providing new insights into the cognitive drivers of such behaviors, aligning with previous research by Kollmuss and Agyeman (2002).
The study offers valuable insights for tourism marketers and policymakers, highlighting the importance of developing marketing strategies that address the diverse environmental knowledge levels of tourists By emphasizing environmental education to foster informed support for sustainable practices, the findings align with Mowforth & Munt's (2015) recommendations For policymakers, these insights are crucial for creating policies that enhance sustainable tourism, including educational initiatives and the promotion of transparent sustainable practices in the tourism sector, as supported by Bramwell & Lane (2011).
Conclusion, Limitations and Future directions
This study enhances the understanding of sustainable tourism by revealing how tourists' attitudes, beliefs, and perceptions of destination image significantly impact sustainable tourism practices It finds that improved environmental knowledge can alter these relationships, indicating a complex decision-making process among tourists The research provides essential theoretical and practical insights, highlighting the need for targeted marketing and educational strategies to promote sustainable tourism behaviors Ultimately, it underscores the intricate factors affecting sustainable tourism and the importance of a comprehensive approach to effectively address these challenges.
The study provides valuable insights into sustainable tourism and tourism marketing in Vietnam but acknowledges limitations in its literature review, which does not fully capture the complexities of these areas The selection of variables may overlook important factors that could enhance understanding Future research should focus on a more comprehensive exploration specific to Vietnam, incorporating a wider range of variables like cultural values and government policies, and utilizing larger, more diverse sample sizes Additionally, longitudinal, qualitative, and mixed-methods studies are recommended to gain deeper insights into trends, motivations, and perceptions, while investigating the role of technology and evaluating the effectiveness of sustainable tourism policies could further advance the field.
Chapter 5 summarizes the findings, highlighting the crucial role of attitudes, beliefs, and perceptions in youths’ support for sustainable tourism and the intricate influence of environmental knowledge on these factors By leveraging the Theory of Planned Behavior, the study enriches sustainable tourism discourse and guides marketing and policy approaches It recommends further investigation into Vietnam's sustainable tourism using diverse methods to deepen insights.
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