The manicured lawns, tree-lined walkways and meticulously landscaped gardens that advertise a university’s environmental virtue may be doing something unexpected behind the scenes: shrinking the way students understand sustainability itself. That is the central finding of a new study of undergraduate students at an elite Chinese university, published in the journal Higher Education, which reports that students’ conceptions of sustainable development were overwhelmingly anchored to the visually striking greenery of their campus, while the social and economic dimensions of the agenda — poverty, inequality, justice, decent work — receded almost entirely from view. The researchers describe the pattern as a “significant ecological bias,” and they trace its origins not to lecture halls or textbooks but to the campus environment itself, which they argue functions as a hidden curriculum: a silent instructor that teaches students, day after day, which parts of sustainability count and which parts can safely be ignored. The implications reach far beyond one picturesque campus.

The stakes extend well beyond a single institution. Higher education institutions are among the most consequential actors in the global effort to deliver the United Nations Sustainable Development Goals, the seventeen interlinked targets adopted in 2015 that encompass climate action, clean energy and the protection of ecosystems, but also zero hunger, gender equality, decent work and reduced inequalities. Universities do not merely research these problems; they shape the assumptions of millions of future engineers, policymakers, managers and teachers, and they are formally recognized as significant contributors to the goals. Yet comparative research across countries has repeatedly found that student perceptions of sustainability are fragmented, defaulting to familiar environmental imagery while social and economic considerations remain abstract. The new study, conducted by Shanyun He, Hongwei Guan and Junqing Zhai of the College of Education at Zhejiang University in Hangzhou, together with Debby R.E. Cotton of Plymouth Marjon University in the United Kingdom, set out to examine how the lived reality of a campus produces that fragmentation, and what it means for students’ willingness to act as future change agents.

To capture what sustainability actually means to students, the team employed a mixed-methods design that combined auto-photography with semi-structured interviews. Auto-photography is a visual research technique in which participants themselves take photographs of scenes they associate with a concept, and those images then anchor an in-depth interview, an approach known as photo-elicitation. Because participants choose the frames, the method surfaces tacit, visually organized knowledge that conventional questionnaires routinely miss, and it limits the interviewer’s framing effects by letting the subject’s own imagery drive the conversation. The undergraduates, drawn from a range of faculties and identified in the published analysis through anonymized codes — such as E5, denoting the fifth participant from the Faculty of Engineering — photographed what sustainable development looked like to them on campus and then explained their choices in interviews. All participants were adults, fully informed about the study’s procedures, and their data were anonymized. The researchers then applied systematic content analysis, coding the photographs and transcripts into recurring categories to map the cognitive terrain of student understanding.

The results were strikingly lopsided. Across photographs and interviews alike, students’ understandings clustered around the campus’s green infrastructure: its vegetation, landscaped grounds and other tangible environmental features that dominate the sensory experience of the site. Sustainability, in the students’ accounts, was something you could see, walk through and maintain — green spaces, conservation, cleanliness, the visible apparatus of an environmentally responsible institution. By contrast, the social and economic pillars of sustainable development, the distributional questions of who benefits, who is burdened and how economic systems generate environmental harm, appeared rarely and remained abstract even when they were invoked. The authors argue that this asymmetry is no accident. The university’s visual environment privileges the environmental dimension precisely because it is tangible and photogenic, while justice and economics, being relational and largely invisible, leave no material footprint on the campus and therefore claim little cognitive territory in students’ minds.

The conceptual heart of the paper is the hidden curriculum, a term educational researchers use for the unwritten lessons an institution transmits through its priorities, norms and physical environment rather than through formal instruction. Sustainability scholars have long warned that what a university does can outweigh what it says, and one of the study’s co-authors has previously examined visual images of sustainability on university campuses, identifying a hidden curriculum of climate messaging. The new research sharpens that argument by proposing that the hidden curriculum acts as a selective filter: by prioritizing tangible environmental greening over abstract social and economic justice, the institution implicitly defines the boundaries of sustainability. The campus, in other words, is not a neutral backdrop to learning but an active pedagogical agent. As the authors conclude, higher education institutions “do not merely teach sustainability; they define the possible through the lived reality of the campus environment.” Visual salience, a well-documented driver of attention and memory in environmental communication, supplies the mechanism through which those institutional values are absorbed.

That cognitive narrowing has behavioral consequences, and this is where the findings become most sobering. Students reported genuine willingness to engage — the researchers explicitly explored their readiness to serve as future change agents — but that willingness concentrated in what the authors call maintenance-oriented behaviors: protecting what already exists, keeping the campus clean, conserving resources, sustaining the very green infrastructure they had photographed. Largely absent was systemic, transformative engagement: questioning underlying economic and social structures, connecting environmental degradation to inequality, or mobilizing around the distributive questions at the core of the Sustainable Development Goals. In the vocabulary of education for sustainable development, which distinguishes maintenance-oriented learning from transformative learning, the campus was producing custodians rather than transformers. Notably, the students were not indifferent: their willingness to act was genuine, which makes the narrowing more consequential rather than less, because motivated energy is being channeled into safe channels instead of systemic ones. The distinction matters because behavioral science, from the theory of planned behavior onward, treats intention as the strongest proximal predictor of action; a generation trained to equate sustainability with horticulture risks carrying that truncated model into boardrooms, ministries and design offices.

The Chinese context amplifies the finding. Green campus construction has been a visible strand of Chinese higher education policy for well over a decade, and it dovetails with the national agenda of ecological civilization, a flagship framework that elevates environmental protection to a core state objective. Previous case studies have documented large-scale energy-saving retrofits and greening programs at Chinese universities, including work at Zhejiang University itself. Yet the same literature that celebrates these achievements has begun to ask what such programs teach. Earlier work by members of the current team examined visual images of sustainability on university campuses and identified a similar hidden curriculum of climate change messaging, and international studies of university students’ engagement with the goals have repeatedly highlighted fragmented, environmentally skewed perceptions. The new study extends that evidence into China’s elite higher education sector, where the physical campus is often exceptionally polished and green branding is woven into institutional identity.

What distinguishes the paper methodologically is that it moves beyond a descriptive snapshot. The authors construct what they call a process-oriented model of sustainability learning, tracing a pathway that begins with institutional discourse — the signals embedded in campus design, operations and official messaging — passes through student meaning-making, in which individuals interpret those signals into working definitions of sustainability, and ends with behavioral intention, the expressed willingness to act. Each stage filters the one before it. Discourse that foregrounds greenery produces meaning-making anchored in greenery, and meaning-making anchored in greenery produces intentions that are protective rather than transformative. Because the model is built from paired visual and verbal data, it captures both the imagery through which students perceive sustainability and the language through which they justify their choices, giving the filtering argument unusual evidentiary depth. The model reframes fragmented student perceptions not as a deficit of knowledge but as a rational reading of the environment students inhabit, and it offers researchers a testable structure for investigating how physical and institutional settings sculpt sustainability cognition across different universities, national systems and cultures.

The practical implications are concrete. The authors call for an integrated pedagogy that proactively bridges the gap between environmental protection and social equity, so that sustainability education fosters what they describe as truly holistic sustainability agency. On a campus, that could mean making invisible dimensions visible: interpretive displays that trace the labor, supply chains and social costs behind familiar infrastructure; coursework and projects that treat campus operations as case studies in all three pillars of sustainable development rather than the environmental pillar alone; and participatory forums where students interrogate whose interests campus greening serves, and who is absent from its benefits. Campus master plans, procurement policies and community partnerships would all need to reflect the same integration, so that the formal curriculum and the physical environment stop sending conflicting messages. The goal, the researchers stress, is not to dethrone environmentalism but to rebalance the triad, so that graduates can hold ecological, social and economic reasoning in a single frame when they confront the interconnected problems the Sustainable Development Goals were written to address.

The study, supported by the National Social Science Fund of China (grant BHA220117), was received by the journal in October 2025, accepted in June 2026 and published online on 16 June 2026. Its authors are careful to note that the findings emerge from a single elite institution, and they present their model as a lens rather than a universal verdict. But the underlying mechanism — that people learn from what their environment makes visible, and unlearn what it hides — is unlikely to respect campus boundaries. For university leaders tempted to measure sustainability in trees planted and panels installed, the message is pointed: students are reading the campus like a text, and right now many are reading a book with most of its chapters missing. Whether universities respond by rewriting that text, or continue to let landscaping do their teaching, may shape the sustainability ambitions of an entire generation.