Persistent disparities in urban tree exposure across global demographics

Jian Lin; Prajal Pradhan; Zhongchang Sun; Min Cao; Qiang Wang; Huadong Guo; Bo Huang; Min Chen

doi:10.59717/j.xinn-geo.2026.100186

The Innovation Geoscience > 2025 Vol. 3 > No. 4 > 100186

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Persistent disparities in urban tree exposure across global demographics

1.
State Key Laboratory of Climate System Prediction and Risk Management, Nanjing Normal University, Nanjing 210023, China
2.
Key Laboratory of Virtual Geographic Environment (Ministry of Education of PRC), Nanjing Normal University, Nanjing 210023, China
3.
Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China
4.
Integrated Research on Energy, Environment & Society, University of Groningen, Groningen 9700 AB, The Netherlands
5.
Potsdam Institute of Climate Impact Research (PIK), Member of Leibniz Association, Potsdam 14473, Germany
6.
Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China
7.
International Research Center of Big Data for Sustainable Development Goals, Beijing 100094, China
8.
State Key Laboratory for Subtropical Mountain Ecology of the Ministry of Science and Technology and Fujian Province, Fujian Normal University, Fuzhou 350007, China
9.
School of Geographical Sciences, Fujian Normal University, Fuzhou 350007, China
10.
Department of Geography, The University of Hong Kong, Pokfulam, Hong Kong SAR 999077, China

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Corresponding authors: bohuang@hku.hk (B.H.); chenmin0902@njnu.edu.cn (M.C.)
Received Date: February 09, 2025

Accepted Date: October 20, 2025

Published Online: October 27, 2025

The Innovation Geoscience 3(4), https://doi.org/10.59717/j.xinn-geo.2026.100186 | Cite this article

GRAPHICAL ABSTRACT

GRAPHICAL ABSTRACT

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PUBLIC SUMMARY

PUBLIC SUMMARY
1. We assess global disparities in urban tree exposure across demographic groups.
  
  We reveal a worldwide increase in overall tree exposure, regardless of city characteristics or location.
  
  We highlight that vulnerable populations consistently experience lower tree exposure than advantaged ones.
  
  These persistent inequities hinder progress toward Sustainable Development Goal 11.
  
  Our findings highlight the urgent need to embed environmental justice in future urban greening.

ABSTRACT

ABSTRACT

Urban greenspaces provide various benefits for human well-being. Despite the overall improvement in greenspace exposure in the 21^st century, it remains unclear whether the distribution and improvement of greenspaces, particularly urban trees, are equitable across population demographics and regions. Here, we quantified disparities in urban tree exposure across various population groups and age cohorts in 1,057 cities globally over a 15-year period (2000–2015). Our analysis revealed persistent and deepening disparities in tree exposure, with cities identified as the least or most exposed in 2000 largely remaining unchanged until 2015, indicating a lack of progress in equitable greening. Notably, the disparity between regions with higher and lower tree exposure widened from 2.7% to 5.9%, in contrast to the nearly doubling of the global average urban tree exposure during the same timeframe. Sex-based differences in exposure are minimal; however, age-related disparities are significant, with older populations experiencing the most exposure and youths the least. This trend intensified over time, while exacerbating exposure disparities and disadvantaging younger demographics. Our findings illuminate challenges in attaining Sustainable Development Goal 11, particularly the aim of universal access to green and public spaces for women, children, and older persons. These insights underscore the need for nuanced urban greening policies that not only expand green cover but also address persistent disparities and prioritize the needs of socially vulnerable subpopulations.
- Exposure differentials /
- Environmental justice /
- Socially vulnerable groups /
- Sustainable development

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Cite this article:

Lin J., Pradhan P., Sun Z., et al. (2025). Persistent disparities in urban tree exposure across global demographics. The Innovation Geoscience 3:100186. https://doi.org/10.59717/j.xinn-geo.2026.100186

Lin J., Pradhan P., Sun Z., et al. (2025). Persistent disparities in urban tree exposure across global demographics. The Innovation Geoscience 3:100186. https://doi.org/10.59717/j.xinn-geo.2026.100186

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