KMS Chongqing Institute of Green and Intelligent Technology, CAS
| Forgotten urban habitats: Analysis of spontaneous vegetation on the urban walls of Chongqing City | |
Chen, Chundi1,2
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| 2020 | |
| 摘要 | Cities are known as " concrete forests, " and they have substantial walls of many types, including buildings, free -standing (boundary), and retaining (those used for reinforcing slopes or to confine river channels). Generally, these completely concrete walls are not considered as habitats. Using a typical mountainous city, Chongqing, as the case study, we aimed at exploring the possibility that urban walls can act as habitats in cities. From September to November 2017, we surveyed 120 walls, across 359 sampling quadrates, to obtain spontaneous vegetation data and associated wall characteristics. The effects of wall characteristics on the variation of spontaneous vegetation was calculated using variance partitioning and canonical correspondence analysis (CCA) ordination method. Vascular plants totaled 193 species in 149 genera from 70 families. The Compositae family had the greatest number of species and was followed by Gramineae and Urticaceae. The dominant species included Pteris vittata, Pteris multifida, seedlings of Broussonetia papyrifera, Cyrtomium fortune, and seedlings of Ficus virens. They occurred in more than 40% of all quadrates. The wall vegetation showed a diverse range of plant life - forms (i. e., woody, fern, and vine). Compared to xerophytes that dominate planar environments, more fern species inhabited the walls. This finding is consistent with that of other studies. This reflects the uniqueness of walls as habitats, and urban walls can act as a valuable complement to urban ecological spaces. The explanatory power of all four wall characteristics was low (14.4%). The spontaneous species assemblage was a complex process, and it was influenced by environmental stochasticity. Additionally, the unexplained portion may come from the influence of the large-scale landscape context. Among all the variables, wall height, vine coverage, and wall shade were the most important factors that influenced vegetation composition and distribution, and they had the highest correlation with the first constrained axis of the CCA ordination. All variables were relevant to wall humidity. This indicates that moisture plays a decisive role in structuring vegetation on urban walls. Lastly, we discussed the implications of this study on greening and landscaping contemporary cities. Urban biodiversity improvement can be done by "allowing nature to work." Our study also provides scientific support for urban ecological design and low-cost management. © 2020 Science Press. All rights reserved. |
| DOI | 10.5846/stxb201804130848 |
| 发表期刊 | Shengtai Xuebao/ Acta Ecologica Sinica
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| ISSN | 10000933 |
| 卷号 | 40期号:2 |
| 语种 | 中文 |
| EISSN | 18722032 |
