Nature-inclusive urban development (NIUD) is central to international frameworks such as the Global Biodiversity Framework, yet its implementation risks fostering social inequity and green gentrification. This study examines these social impacts through a sequential mixed-methods investigation combining semi-structured interviews and a representative survey in Qunli New Town, Harbin, China, a prominent case of NIUD incorporating landscape-level ecological mitigation and compensation. We found that well-being changes among original residents were linked to adaptation to the new context. Compared to non-agriculturalists (e.g., former small-scale industry workers), former agriculturalists reported a sharper happiness decline relative to the pre-urbanisation era (OR=0.15, P<0.001). Among all original residents, those perceiving increases in social (OR=1.30, P=0.0049) and aesthetic (OR=1.53, P<0.001) values of green spaces reported happiness gains. A critical finding was the stark divergence in fairness perceptions: original residents perceived ecological fairness to be substantially lower than newcomers (OR=0.54, P<0.001) but economic fairness higher (OR=1.93, P<0.001). This was shaped by the rural reference points of original residents—both former agriculturalists and non-agriculturalists— which led them to value economic upgrades, while experiencing ecological displacement from the loss of customary practices and access to previously accessible landscapes. To advance equitable NIUD, social impact assessments should explicitly manage the gentrification trade-off between new green infrastructure and the loss of cultural landscapes, promoting justice for different waves of settlement.
