Research

INTRODUCTION

At a time when environmental issues have already become major global problems, the question arises as to what influences people’s environmental behavior. The perception of the value of nature is seen as an important factor that can have a decisive influence on decision making (Pascual et al. 2023). In the past, a value dichotomy between the instrumental and intrinsic value of nature was often assumed (Tallis and Lubchenco 2014, Pascual et al. 2017). In the case of intrinsic value, nature and biodiversity are assigned a value simply because of their existence (Soulé 1985). This value is inalienable, i.e., it cannot be denied and is independent of any evaluation by humans. Nature should, therefore, be protected for its own sake (Soulé 1985, Sandler 2012). However, this view is often criticized: for example, protecting nature for its own sake is seen by some as outdated and impractical (Soulé 2014), and it is not clear whether this valuation of nature can really increase environmentally friendly behavior (Justus et al. 2009). Therefore, supporters of the instrumental view argue that the instrumental approach is easier for more people to understand than the intrinsic value of nature (Tallis and Lubchenco 2014). The instrumental perspective focuses on the benefits nature provides to humans rather than nature’s intrinsic worth (Bullock 2017). This perspective is closely linked to the ecosystem services from which humans benefit (Reyers et al. 2012). In the instrumental valuation of nature, a part of nature is replaceable if another or new part fulfils the same function (Sandler 2012). However, this view is also criticized by some as a sell-out of nature (McCauley 2006). It is also problematic that only parts of nature that have a benefit for humans are considered worthy of protection, which leaves out parts that have little or no obvious benefits (Tallis and Lubchenco 2014).

Nowadays, value pluralism is increasingly discussed in environmental valuation as an approach to integrating diverse perspectives on nature’s worth. However, it remains an evolving and contested framework (Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) 2018, Pascual et al. 2023). Value pluralism refers to the idea that multiple values coexist that cannot be reduced to a single overarching metric (Chang 2015). Although some authors see value pluralism as an important step for sustainability and as a way to integrate diverse perspectives on nature’s contributions to people, others criticize that privileged actors may have greater influence on which values are recognized (Pascual et al. 2017, Jacobs et al. 2020, 2023).

Besides instrumental and intrinsic values of nature, another type of environmental values has also attracted increasing attention in recent years: the concept of relational values (RVs), in which human–nature relationships and nature-centered human relationships play an important role (Díaz et al. 2015). Relational values refer to meaningful relationships people form with nature and with each other through nature, encompassing ethical responsibilities, cultural significance, and identity. They extend beyond the conventional dichotomy of intrinsic and instrumental values by emphasizing the importance of relationships themselves (Chan et al. 2016, Pascual et al. 2017). These values are grounded in notions of stewardship, care, identity, and social cohesion, shaping how individuals and communities interact with and assign meaning to nature (Chan et al. 2018, Pratson et al. 2023). However, the term “RVs” is constantly evolving and may be used with slightly different nuances by authors (Pratson et al. 2023, Himes et al. 2024). Relational values provide an important lens for conservation by recognizing why people form attachments to places/nature and how these connections influence decision making (Himes and Muraca 2018, Pratson et al. 2023).

The concept of RVs has been further refined in recent years and aligned with well-known environmental value concepts such as assigned, moral, and held values: RVs include assigned values (values of objects) and moral values (what is right). However, held values, which describe higher ideals or principles (e.g., fairness, generosity) and are more abstract, differ from RVs because RVs are always linked to concrete relationships involving nature (Chan et al. 2018). Relational values are increasingly recognized as crucial for sustainability, as they encompass and promote a sense of responsibility, care, and stewardship toward nature, supporting long-term environmental commitments (Martin et al. 2024). Relational values also play a significant role in shaping environmental behavior (van den Born et al. 2018, Topp et al. 2022, Uehara et al. 2022). In addition, they can serve as the main drivers and key motivators for participation in conservation activities (Knippenberg et al. 2018, Mattijssen et al. 2020). Even before the term was introduced, RVs or parts of them were identified in the environmental education sector, without naming them as such (Britto dos Santos and Gould 2018). However, the boundaries between RVs and instrumental and intrinsic values of nature are often blurred, as different types of values can be ascribed to or derived from the same part of nature (Himes et al. 2024, Riechers et al. 2025).

Due to this great importance of RVs, research has been conducted in different regions of the world and in various scientific disciplines, often using different methods and objectives (Pratson et al. 2023). Although these studies provide valuable insights, there is a lack of broader, comparative approaches to identify universal and culturally specific aspects of RVs. Furthermore, the majority of existing quantitative RV assessments are conducted at a national or local scale, thereby creating a knowledge gap about the global perception of RVs. Further quantitative studies are, therefore, needed: for example, to identify elements within RVs that occur in different cultures (Schulz and Martin-Ortega 2018). A particularly interesting group in this context are students in the environmental and sustainability field.

Universities play an important role when it comes to the development of sustainability. They educate future decision makers, leaders (Alshuwaikhat and Abubakar 2008, Bellou et al. 2017), professionals (Kioupi and Voulvoulis 2020), and intellectuals in the academic field (Lozano 2006). Although important positions in society can be achieved without university education, university education favors the achievement of such positions, as skills and knowledge are taught there (Vicente-Molina et al. 2013).

How these future decision makers in the environmental sector evaluate RVs is largely unknown. At the moment, such studies only exist in a national context, if at all (Feucht et al. 2023). Therefore, especially for this group, it would be beneficial to find out more about their perception of RVs, as they are likely to make environmentally relevant decisions later in their career. Conducting surveys among students provides valuable insights into the perspectives of future environmental decision makers. However, the survey population is not without its limitations. Students may not fully represent the broader population due to the influence of their academic background or socioeconomic status (Greenfield 2014, Hanel and Vione 2016).

This study, therefore, aims to answer the question of how students in environmental and sustainability related fields worldwide evaluate RVs and whether global patterns in these perceptions can be identified. To provide initial explanations for the results and to check whether a country’s wealth plays a role in the assessment of RVs, the results were correlated with selected country-specific wealth indicators. These wealth indictors were chosen because previous international studies have already shown that a country’s wealth can influence the perception of nature and environmental problems (Inglehart 1995, Franzen and Meyer 2010, Franzen and Vogl 2013, Aral and López-Sintas 2023). A recently developed method was used to simplify the analysis and the comparison of different groups within this international data set.

METHODS

Data collection procedure and participants

To assess the RVs in different regions, surveys were conducted in a total of 45 countries. The selection of the 45 study countries was guided by the objective of achieving a broad geographic representation across continents and diverse socio-economic contexts. Although no strict selection criteria were applied, the aim was to include a sufficient number of countries across Asia, Africa, Europe, North and South America, and Oceania to obtain a global perspective.

An online questionnaire was created to reach students in the individual countries. To ensure the highest possible level of data protection, the survey platform of the Goethe University Frankfurt (Germany) was used. The survey was sent by e-mail to professors, laboratory managers, and research assistants in the selected countries with the invitation to distribute it among their students. As students in the environmental fields (ecology and conservation, environmental science, biology, natural resources management, etc.) were selected as the target group, only university staff with a focus on this subject area were contacted. Researchers were selected through academic networks and institutional directories. Although institutional differences were not systematically analyzed, the study tried to include at least two universities per country, ensuring diverse academic contexts for the examination. In a text accompanying the study, the students were informed about the objectives, the voluntary nature of participation, and data protection.

To achieve a sufficiently large data set, at least 50 researchers in each country were contacted by e-mail and asked for their support. In the e-mail, the objectives of the study, data protection, and the voluntary nature of participation were briefly explained. The questionnaire was offered in at least one official national language of each country. The translations were carried out by native speakers and checked by a second person in each case.

The minimum sample size per country was set at 30 students. This cut-off was reached by 37 countries. Data from the eight countries that did not reach this cut-off value were excluded from the analysis. Students from disciplines not related to the environmental field and Ph.D. students were excluded before the data analysis. Only students who were studying in their country of origin were included in the analysis. Participants who indicated a different country of origin than the country where they were enrolled were excluded to minimize potential bias from international mobility. A total of 4571 (33.46% male, 64.68% female, 0.96% diverse, 0.9% no answer) questionnaires were valid according to these criteria. On average, the respondents were 22.44 (± 4.59) years old and in the fourth semester of their studies. The survey period was from September 2020 to July 2021. The sample size broken down by survey country can be found in Table 1.

The survey was approved by the ethics committee of the science didactic institutes and Departments of the Goethe University Frankfurt am Main under approval number 15-WLSD-2104.

Measurement instrument

At the beginning of the questionnaire, general demographic data such as age, gender, semester of study, course of studies, university, and which country the students originally came from were recorded.

Measuring relational values (RVs)

Because RVs are a relatively new construct, there are only a limited number of empirical studies on this topic and no established survey instrument is yet available. Some studies assessed RVs through open-ended questionnaires or interviews (Arias-Arévalo et al. 2017, Chapman 2017). However, quantitative instruments have also been applied in recent years (Klain et al. 2017, See et al. 2020, Uehara et al. 2020, Riechers et al. 2021). In this study, the seven questions of Klain et al. (2017) were used because, on the one hand, the scale covers the construct of RVs very well and, on the other hand, its applicability has already been demonstrated in other research (Kleespies and Dierkes 2020b). The seven items and the explanation of their content validity can be found in Table 2. The seven items were to be rated on a five-point Likert scale from strongly agree to strongly disagree.

Analysis

It is known that the RVs are highly context dependent (Himes and Muraca 2018), and it can be expected that the different components of the RVs were assessed differently in the countries surveyed. It is, therefore, difficult to compare the data using standard procedures, such as factor analysis, as it can be assumed that the results of the factor analyses differ considerably among the countries (Append. 1). Therefore, an unsupervised learning-based clustering approach recently developed by Hahn-Klimroth et al. (2024) was used to evaluate the data collected here, which is particularly suitable for analyzing and presenting data from different groups. The aim of this analysis was to explore patterns in RVs among environmental students across different countries and how these are distributed in the individual countries. The main advantage of this method compared with a factor analysis is that no structural simplification is carried out, and all items are used jointly throughout the analysis. This means that there is no generalization of items or groups of items, as would be the case if an overall factor analysis were to be carried out with all data and the result applied to all countries.

The method used, proposed by Hahn-Klimroth et al. (2024), is based on a well-studied unsupervised learning method, highly present in the data science community. The current contribution does not intend to present the method in detail, but we refer to the original contribution for the discussion of the statistical foundations. The method is based on cluster analysis and allows distinguishing groups with the same “typical answer” but highly different levels of group homogeneity, in contrast to factor analysis. It proceeds in three steps.

First, missing data in the questionnaires were imputed. Here, 8-nearest neighbor imputation was chosen as an imputation technique, as this takes the correlation between different items into account, in contrast to basic imputation methods like taking the row or column mean (Troyanskaya et al. 2001). Moreover, in this step, questionnaires per country were oversampled to the number of questionnaires in the country with most questionnaires. This means that, per country, randomly chosen questionnaires were duplicated until all countries had the same number of questionnaires. This is required to obtain a meaningful clustering in the next step (Hahn-Klimroth et al. 2024). As usual in oversampling, each item’s value is perturbed with independent additive Gaussian noise with mean zero and standard deviation 0.1. This increases the stability of the clustering algorithm and reduces potential side-effects of oversampling (Min et al. 2020). Second, the set of oversampled questionnaires is clustered. The centroid of each cluster class, the “typical questionnaire in this cluster,” is called “response type.” The optimal number of cluster classes found is determined by a heuristic argument based on the so-called gap statistic (Append. 2; Hahn-Klimroth et al. 2024). Third, for each country, the proportion of questionnaires belonging to each of the six cluster classes is calculated. This quantity is a point on the sixth dimensional simplex and is called “fingerprint” (Hahn-Klimroth et al. 2024). The fingerprint is a natural description of the distribution of response types in the different countries.

To determine whether the distribution of the individual response types in the countries is related to the wealth of a country, the percentage distribution of the response types was correlated using Spearman’s correlation with two selected prosperity indicators, the Human Development Index (HDI) and the Legatum Prosperity Index (LPI) (Fig. 1).

The HDI (United Nations Development Programme (UNDP) 2020a) is an index that reflects life expectancy, expected years of school attendance, and the standard of living. The index can take values between 1 and 0, with 1 being the highest value (UNDP 2020b). The LPI assesses the prosperity of a nation considering 300 individual indicators in 12 overarching topics. A high score represents a high level of prosperity (Legatum Institute 2021).

RESULTS

Based on the data, the questionnaires can be divided into six higher-level response types. In response type 1, all seven RVs items were rated highly, without much variation. In response type 2, there was only a low level of agreement with the seven items, and here too, the variation was relatively low. In type 3, the items were rated relatively high, with the exception of RV_iden and RV_kin, which were in the medium range. The variation is slightly higher in this type. Response type 4 shows very little agreement with item RV_wild, whereas all other items have high agreement values. Type 5 shows the highest variation, with the items RV_iden, RV_kin, and RV_wild being rated lower. In the last response type, 6, agreement with the item RV_comm is particularly low, but the item RV_wild is also rated slightly lower than the other items. The variation is also comparatively high in this type (Fig. 2, Table 3). The distribution of the individual response types in the countries surveyed can be found in Table 4 and Append. 3.

The correlations between the proportion of individual response types in the countries and the country-specific wealth indicators show values in the low to high range (Table 5).

DISCUSSION

The results of the analysis show that there are six different response types in the evaluation of the RVs items, which occur globally and can be distinguished from each other. The approach of determining response types and then categorizing them into higher-level fingerprints within individual countries provides a robust method for identifying response patterns across diverse groups without requiring the strict assumptions of traditional multivariate techniques such as factor analysis or principal component analysis (Yong and Pearce 2013, Hahn-Klimroth et al. 2024). A key limitation of these conventional methods is that they assume a single, consistent factor structure across all groups (Putnick and Bornstein 2016), meaning that the same underlying dimensions must explain responses in every country. However, such a consistent structure is unlikely, as RVs are highly context dependent, and their components can be perceived differently across cultures (Himes and Muraca 2018). The fingerprint approach overcomes this issue by clustering individuals based on naturally emerging response patterns rather than forcing responses into a predefined factor model. Instead of assuming that RVs are structured the same way in all countries, this method allows response types to emerge freely, reflecting cultural and contextual differences. This approach also avoids the need to statistically test for measurement invariance, which is often required in traditional factor-based analyses to ensure comparability across groups (van de Schoot et al. 2015). Another advantage of the fingerprint approach is that it focuses on identifying distinct global response types rather than averaging responses at the country level. This reduces the risk of oversimplifying complex value structures by forcing them into a uniform framework. Instead, the method highlights how different response types can exist within and across countries, offering a more flexible way to study how RVs manifest in different contexts.

Response type 1 occurs most frequently in almost all countries. In this type, all items of the scale were rated very high, which means that the students agree with the RVs. These results demonstrate that environmental students, as future decision makers of society, see nature not only as an instrumental asset, but also as a place of connection between people and nature, as a health resource, and as an entity for whose preservation there is a moral obligation. The widespread presence of response type 1 in all countries can, therefore, be interpreted positively from the perspective of protecting ecosystems and nature, as RVs can be seen as an important motivator for the protection of nature and as a driver for environmental conservation (Knippenberg et al. 2018, Mattijssen et al. 2020, Uehara et al. 2022). In addition, RVs are an important factor in promoting positive environmental behavior (van den Born et al. 2018, Topp et al. 2022) and also provide decision makers with a possible basis for argumentation to protect parts of nature, even if an instrumental value cannot be directly demonstrated (Schulz and Martin-Ortega 2018). Different studies have already shown that RVs are widespread internationally: they have been demonstrated in Europe (Feucht et al. 2023), Asia (Uehara et al. 2020, Saito et al. 2022), Africa (Cundill et al. 2017), North America (Klain et al. 2017), South America (Guerrero-Leiva et al. 2021), and Australia (Russell and Ens 2020). The study carried out here demonstrates in one data set and in a direct comparison among countries that RVs not only exist worldwide but are also widespread. In this context, it should be noted that the uniformly high agreement with all RVs items in response type 1 may reflect a potential ceiling effect, in which high values limit the ability to distinguish among respondents. The high occurrence of response type 1 may be partly influenced by the positive framing of the survey instrument, which primarily emphasized connections with and care for nature. Although this framing was designed to align with the theoretical foundation of RVs, it may have encouraged respondents to express more relational and stewardship-oriented views than they otherwise might have in an open-ended assessment. It would be worthwhile for future research to explore whether different framing would yield different response distributions.

The appearance of response type 1 also shows a negative medium bordering on strong correlation with the wealth indices of the countries. This means that this type occurs less frequently in wealthier countries. One possible explanation for this could be that people in these countries in particular are becoming disconnected from nature. Especially for wealthier countries, it has been documented that a lot of time is spent outside of nature (Conrad et al. 2013, Matz et al. 2014, Bassett et al. 2015). This increasing loss of human–nature interactions (Soga and Gaston 2016) might lead to a declining relationship with nature and, therefore, a decline in RVs. Interestingly, this inverse relationship contrasts with findings from wildlife value orientation research, where higher wealth, education, and urbanization have been linked to a shift toward mutualist values rather than traditionalist or instrumentalist perspectives (Manfredo et al. 2009, 2020). This seeming contradiction with Manfredo and colleagues’ findings may be explained by the conceptual differences between RVs and mutualist wildlife value orientations. Although both concepts emphasize care for nature and wildlife, mutualist orientations assume wildlife has moral equality and should be granted rights that are similar to those of humans (Manfredo et al. 2009). Relational values are broader in scope and include social and cultural dimensions in addition to the personal relationship with nature. These conceptual distinctions may help to explain why our findings differ from the patterns described by Manfredo et al. (2020).

Whether instrumental or intrinsic value systems are more predominant in the wealthier countries cannot be determined from this data set but would require further research.

Response type 2 stands in direct contrast to response type 1, as it represents a complete rejection of RVs. As RVs are recognized as important factors in supporting nature conservation, a wider distribution of this response type could harm environmental protection. In cases where the instrumental value of nature is unclear or difficult to quantify, RVs can provide a key argument for conservation efforts, helping to justify protective measures (de Vos et al. 2018). If relational perspectives are not considered, conservation decisions may be based solely on economic or ecological arguments, which may not always be sufficient to justify protective measures. Relational values can help secure conservation support by highlighting the cultural, social, and ethical significance of ecosystems (Arias-Arévalo et al. 2017, van Noordwijk et al. 2023). If RVs are not recognized, these arguments are no longer available, potentially reducing public and policy support for nature protection.

However, it should be noted that this response type only occurs rarely: in more than half of the countries surveyed, this type is not found at all, and in the remaining countries, it generally only occurs in the single-digit percentage range. In addition, this response type shows no significant correlation with the wealth of the nations surveyed. This provides evidence that this response type occurs regardless of a nation’s wealth.

In the third response type, the two items RV_iden and RV_kin were rated lower than the other RV items. These two items reflect whether nature is seen as part of one’s own personality. This part of the RVs is, therefore, very similar to the concept of connection to nature. Connection to nature generally refers to the personal relationship someone has with nature (Schultz 2002, Mayer and Frantz 2004, Tam 2013). A whole range of different measurement instruments have been developed over the last few decades to measure connection to nature, for example, the Nature Connectedness Scale by Mayer and Frantz (2004), the Inclusion of Nature in Self Scale by Schultz (2002), the Nature Relatedness Scale by Nisbet et al. (2009), or the Nature Connection Index by Richardson et al. (2019). For the two items RV_iden and RV_kin, it has also been empirically shown that they are strongly related to the Nature Connectedness Scale (Kleespies and Dierkes 2020a).

A low value for these items, as found in response type 3, indicates that the personal connection to nature is weaker than, for example, concern for nature or the moral obligation to protect it. The personal connection to nature has repeatedly been shown to be an important motivator for the protection of nature (Mayer and Frantz 2004, Frantz et al. 2005, Kaiser et al. 2008) and has a major influence on environmental behavior (Whitburn et al. 2020, Barragan-Jason et al. 2022). Even if this group only accounts for a small percentage in most countries, it could still influence environmental protection, particularly among future decision makers whose actions will shape sustainability policies. A lower connection to nature does not necessarily mean that individuals will stop engaging in pro-environmental behaviors, as moral obligation or social responsibility can still drive conservation actions. However, connection to nature remains an important factor for fostering pro-environmental behaviors, especially for individuals who lack other personal motivations for environmental engagement. If this connection declines, it could reduce intrinsic pro-environmental behaviors, potentially weakening long-term support for sustainability efforts.

There is also a strong positive correlation between the occurrence of this response type in a country and the selected country-specific wealth indicators. This indicates that this type, in which there is a lower connection to nature, is particularly widespread in wealthier countries. The exact factors responsible for the lower connection to nature in wealthier countries are beyond the scope of this study. One possible explanation for this could be the decline in opportunities for contact with nature (Soga and Gaston 2016) or the increase in screen time (Schultz 2002, Larson et al. 2019). This finding is consistent with other international studies that have found a decline in the connection to nature, especially in wealthier countries (Richardson et al. 2022b, Kleespies and Dierkes 2023b)

In response type 4, the item RV_wild, which describes concern for natural places, is rated particularly low, whereas all other items show high values. In the literature, concern or care for the environment is often understood as environmental attitudes (Gifford and Sussman 2012). Environmental attitudes are considered important factors influencing environmental behavior (Minton and Rose 1997, Levine and Strube 2012), even if there are different results on the strength of this relationship (Marcinkowski and Reid 2019). As this response type is common in some countries, it is of particular importance.

At the same time, this type shows no significant correlation with the wealth indicators. This is partly consistent with findings from the literature. Some studies have found that environmental concerns and attitudes are positively correlated with a country’s wealth, i.e., people in wealthier countries are more concerned about environmental problems (Franzen and Meyer 2010, Franzen and Vogl 2013, Aral and López-Sintas 2023). However, there are also other studies that have been unable to show such a relationship between attitudes toward the environment and a country’s wealth (Boeve-de Pauw and van Petegem 2010). It should be noted at this point that the individual item RV_wild does not cover the entire spectrum of environmental attitudes but is at best an indicator of these. Moreover, RV_wild specifically reflects concern for natural places, which is more location based and tangible compared with the broader concept of environmental attitudes. Future research should explore additional measures to better understand the link between RVs and broader environmental attitudes.

Response type 5 can be seen as a combination of response types 3 and 4 and occurs less frequently. In this type, the three items RV_wild, RV_iden, and RV_kin are rated comparatively low. The explanations of the two previous response types can therefore also be applied to this type. However, as more parts of the RVs are rated as less important in this type, this type should be viewed more critically. The significant high correlation with the wealth indicators can probably be attributed to the connection to nature (see response type 3).

In response type 6, the item RV_comm was rated lower than the other RV items. This item deals with cultural identity and nature as a place to connect people. As there is currently still not enough empirical research on the underlying mechanisms that shape the perception of community-building aspects of RVs (Schulz and Martin-Ortega 2018), it is difficult to determine why people see or do not see nature as a community-building element. One possible explanation could be that local communities have less contact and bonds with nature and, therefore, no longer see nature as a community unifying element. There is currently still a great need for research in order to find out exactly which factors influence the RVs core components. As there is also no significant correlation between this response type and the wealth of a country, new explanatory approaches should be specifically explored.

IMPLICATIONS

The six response types provide important information on how RVs are perceived by environmental students worldwide. The correlations with a nation’s wealth indicators also provide initial explanations for the distribution of these views. As RVs can influence environmental behavior and decision making, understanding their patterns could provide strategies for fostering conservation-supportive attitudes. However, different RVs types may contribute to conservation in distinct ways, depending on cultural, ecological, and policy contexts. Therefore, rather than assuming that a single response type is universally more desirable, future research should examine how various RVs translate into conservation outcomes across different settings.

A literature review suggests that environmental education programs may help strengthen different aspects of RVs (Britto dos Santos and Gould 2018). Therefore, more environmental education could be integrated into the curriculum for environmental students to promote RVs. Uehara et al. (2020) showed that environmental education programs that take place with people from local communities, restore ecosystems, or include an active experience of a local culture in connection with nature can strengthen RVs. Active outdoor learning can also be seen as a way to increase RVs (van den Born et al. 2018). Sharing experiences with a mentor, for example, through outdoor experiences, may also be a way to improve RVs (Chan et al. 2016).

There is a whole range of research results on what measures can increase the personal connection to nature, which would be particularly recommended for response types 3 and 5: for example, the time a person spends in nature is an important impact factor (Lengieza and Swim 2021), but also environmental education (Barrable and Booth 2020) and active experiences of nature (Richardson et al. 2022a). Various studies have shown that contact with nature and mindfulness practices are particularly effective in promoting a connection to nature (Barragan-Jason et al. 2022). There are a number of other suggestions for universities that can help to improve students’ personal relationship with nature, such as the direct integration of local nature into courses or the use of new technologies to establish a relationship with nature (Kleespies and Dierkes 2023a). Also, weakened positive environmental attitudes, as found in questionnaire types 4 and 5, might be improved by spending time in nature (DeVille et al. 2021).

Although the fingerprint-based approach adopted here has the advantage of identifying response patterns across countries without assuming measurement invariance, it is important to note that it is not without limitations. It is essential to recognize that valuation studies, including this one, are shaped by methodological choices that influence outcomes (Jacobs et al. 2023). The survey sample consisted exclusively of university students, which may limit the generalizability of the findings and exclude perspectives from other demographic or social groups. Furthermore, the use of a standardized survey format may have resulted in the exclusion of culturally specific expressions of RVs, particularly those rooted in local traditions.

LIMITATIONS

Although the study was conducted with great care, there are some limitations that need to be addressed. For example, in some countries, the sample size is comparatively small, which may have limited the representation of diversity within the student population of these countries. In addition, only students in the environmental field were surveyed. Our student sample, therefore, does not fully reflect the socioeconomic composition of national populations. University students are often younger and come from more educated and economically advantaged backgrounds than the general population (Greenfield 2014, Hanel and Vione 2016), which may influence their RVs orientations. The results can, therefore, not be transferred directly to other students or the general population of a country. This is particularly relevant when interpreting correlations between the fingerprints and national economic indicators, as these relationships may reflect patterns specific to the student sub-samples rather than broader societal trends. However, as the same group was surveyed in all countries, the results remain comparable. Nevertheless, the data provide important initial indications of the distribution of RVs in a global context.

It should also be noted that the survey was voluntary and anonymous. This may have led to a self-selection of participants: it is possible that more people filled out the questionnaire who are particularly interested in environmental issues. As this factor plays a role in all countries, the results remain comparable.

Another limitation of this study is the gender imbalance in the sample, as women were overrepresented among the surveyed students. This is a common pattern in survey-based research, as studies have shown that women are generally more likely to participate in surveys, particularly in web-based questionnaires (Becker 2022). Although this higher participation rate is expected, it may have influenced the results, as research suggests that women tend to express stronger RVs than men (Kleespies and Dierkes 2020b). As a result, the observed distribution of RVs may skew toward higher reported agreement with RVs, potentially affecting cross-group comparisons. Although this does not invalidate the findings, it highlights the need for future research to examine whether similar RV patterns emerge in more gender-balanced populations and to further explore how gender-related participation biases may influence RVs assessments.

In addition, it cannot be ruled out that, despite careful translations, the meaning of the questions was slightly altered, and they were, therefore, perceived differently by the study participants. Although attempts were made to address this problem by reviewing the translations, this factor cannot be completely prevented.

Moreover, data collection took place during the COVID-19 pandemic, a period in which many people spent more time outdoors and reported a heightened appreciation of nature (Morse et al. 2020). This may have temporarily influenced respondents’ relational values, potentially leading to stronger expressions of RVs than under normal conditions.

CONCLUSION

The results of the study provide an initial overview of RVs among environmental students worldwide. It is positive to note that a large proportion of students in most countries belong to response type 1, which reflect strong RVs. In the future, possibilities should be examined to strengthen students’ RVs, as these can be seen as an important opportunity to improve environmental behavior. However, further research is needed to determine which specific measures are suitable to achieve this goal.

The correlation between the wealth indicators also shows that questionnaire type 1 is less common in wealthier countries, whereas questionnaire types 3 and 5 occur more frequently. For this reason, the possible deficit in these countries in particular should be further analyzed and investigated. In this way, an important contribution can be made to the preservation of ecosystems, nature, and the environment.

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