Beyond the metropolis: Street tree densities and resident perceptions on ecosystem services in small urban centers in India

Anujan, K.; Velho, N.; Kuriakose, G.; P J, E.; Nagendra, H.

doi:10.1101/2022.09.28.509699

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bioRxiv · 10.1101/2022.09.28.509699

Beyond the metropolis: Street tree densities and resident perceptions on ecosystem services in small urban centers in India

Anujan, K.·Velho, N.·Kuriakose, G.·P J, E.·Nagendra, H.

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Abstract

The role of urban street trees has been extensively studied in large metropolises, where they contribute significantly to faunal habitat, provide critical ecosystem services to residents and contribute to human well-being. On the other hand, rapidly urbanizing cities in India have been poorly studied, despite multiple types of irreplaceable losses related to tree cover. However, being early in their urbanization history, these centers also represent opportunity for urban sustainability with potentially high remnant vegetation and human-nature connections. While megacities in developed countries move towards biophilic urban planning and participatory decision making, basic information on tree communities and their perceived services is a bottleneck in achieving these goals in such small urban centers. We assessed the street tree community and resident perceptions of ecosystem service values in Kochi and Panjim, two coastal cities in India under rapid development, through a combination of field measurements (258 transects, 931 trees) and semi-structured interviews (497 individuals). We found that mean street tree density is low in both cities, especially so in Kochi, and corresponds to perceptions of recent change in tree cover (-28% in Kochi, -11% in Panjim). The street tree community in both cities were dominated by ornamental avenue trees such as Albizia saman and Peltophorum pterocarpum, but native coastal species like Cocos nucifera, Terminalia catappa and Thespesia populnea were also common. Despite recent urban growth, residents in both cities reported low value of trees for food, fodder and medicine, but high value for regulating services like shade and water. Moreover, we found strong evidence for aesthetic and cultural values of trees in both cities, including through qualitative interviews. Our study establishes critical baselines for biophilic planning in these small urban centers towards urban sustainability.

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Anujan, K., Velho, N., Kuriakose, G., P J, E., Nagendra, H.. 2022-09-30. Beyond the metropolis: Street tree densities and resident perceptions on ecosystem services in small urban centers in India. https://doi.org/10.1101/2022.09.28.509699

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