How Well Do Three Tree Species Adapt to the Urban Environment in Guangdong-Hongkong-Macao Greater Bay Area of China Regarding Their Growth Patterns and Ecosystem Services?

Chi Zhang,Murong Su,Wanhui Qian,Honghui Tang,Lijun Pan,Qing Zhao

doi:10.3390/f11040420

Abstract

It is predicted that global change combined with urbanization will impact increasingly on the society and terrestrial ecosystem in the Guangdong-Hongkong-Macao Greater Bay Area of China (GBA). In this context, the cities in GBA began to plant a variety of urban trees since 2000 which are considered to play an important role in fixing carbon, improving air quality, reducing noise and providing other ecosystem services. However, data on the growth patterns and ecosystem services of the planted trees remains scarce, which hampers a comprehensive understanding of how well the planted trees adapt to the local urban environment. Therefore, we selected three widely planted tree species in Foshan, one of the core cities in GBA and investigated their tree growth and ecosystem services via a harvest campaign and soil analysis. With the same, fast tree growth as natural forests and the greatest above- and below-ground biomass among the three tree species, Ml (Mytilaria laosensis Lec.) showed a distinguished adaption to the local urban environment in terms of growth patterns, carbon fixation, stabilization against typhoon risk and water uptake capacity against potential drought risk in the future. Although Cf (Chinese fir) showed reduced diameter at breast height (DBH) and volume development, it significantly increased the total and available potassium in soils to improve the soil quality. The DBH growth of Sp (Slash pine) decreased between six and 12 years old while it recovered at the age of 12 years, probably suggesting its adaptation might take a longer time. Our results indicated that different trees had different growth patterns and ecosystem services after they were planted in cities. In a harsh urban environment under climate change, precise and comprehensive data on urban trees is necessary, helping to provide different perspectives for urban managers to select appropriate tree species and make policies.

Highlights

Urban areas around the world are expanding rapidly and will have more than 60 percent of the estimated world population by the year 2030 [1,2], and in association with which, the impacts of global change have become more serious than in previous decades in cities [3,4]
Except for BD of Chinese fir (Cf) in 75–100 cm (p = 0.008) and FC of Ml in 75–100 cm (p = 0.019) which were significantly higher, there were no significant differences between the three tree species in all the corresponding soil layers (p > 0.05)
It is predicted that global change combined with urbanization will impact increasingly on the society and terrestrial ecosystem in Greater Bay Area of China (GBA)

Summary

Introduction

Urban areas around the world are expanding rapidly and will have more than 60 percent of the estimated world population by the year 2030 [1,2], and in association with which, the impacts of global change have become more serious than in previous decades in cities [3,4]. It is widely acknowledged that urban trees can be a key component in the adaptation of cities to climate change and provide ecosystem services accompanying rapid urbanization [5,6,7], including improving urban air quality, reducing noise, attenuating storm-water flooding and conserving energy, which have drawn increasing. There is an increasing demand for data on urban trees; multiple factors might prevent researchers from obtaining profound knowledge of the growth and ecosystem services of urban trees

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Discussion

Conclusion