Urban Trees Associated With a Reduction in Negative Sentiment With Stronger Links During COVID-19

MCML Authors

Xiaoxiang Zhu

Prof. Dr.

Core PI

Data Science in Earth Observation

Abstract

Negative emotions spread rapidly on social media, amplifying urban mental health risks, yet evidence linking tree exposure to real-time emotional expression remains scarce. Combining high-resolution satellite imagery with geotagged social media data from over 400 Brazilian cities (2018–2022), we quantify the effects of tree cover on individual negative sentiment via fixed-effects models controlling for meteorological, environmental and socioeconomic factors. We find each 1-percentage-point increase in tree coverage is associated with a reduction of 0.028 in negative sentiment scores before COVID-19 and 0.042 during COVID-19 (P < 0.001), with the association nearly 1.5 times stronger during the pandemic than in the pre-pandemic period. Tree benefits increase with canopy cover up to 40%–45%, after which additional gains diminish. Benefits are stronger in wealthy regions but weaker under high temperature, precipitation and population density. Our findings provide evidence-based tree planning targets for urban mental health, supporting SDG 3.4 and SDG 11.7.

article GGW+26

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Nature Cities

3. Sep. 2026.

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Authors

J. Guo • H. Guo • J. Wang • D. Hong • A. Kruspe • X. Zhu

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Links

DOI

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Research Area

 C3 | Physics and Geo Sciences