Abstract Urban afforestation is an important strategy for promoting sustainable urban development. In cities where large new green spaces are not available, the planting of curbside trees is deemed to be an important afforestation strategy. However, variations in the ecosystem services provided by street tree assemblages across socioeconomic gradients have been underexplored. We examined such variations in ecosystem services provided by street tree assemblages along an urban-suburban continuum. Our findings were as follows. (1) Not all ecosystem services showed increasing trends along the urban-suburban continuum. Some ecosystem services at the street tree assemblage level, such as air purification and rainfall interception were prominent in areas of high urbanization intensity. (2) Diverse ecosystem service trends were found in relation to differential characteristics of street trees assemblages. Structural properties of street tree assemblages, such as tree density and age structure, are likely key factors influencing variations. (3) Although street tree density could partially compensate for the loss of large old trees, the protection of such trees is important because of their close associations with key ecosystem services, such as total carbon storage. To maximize the value of street trees in promoting urban sustainable development, trade-offs among multiple ecosystem services should be integrated within the overall planning process and adjustments of planting regimes.

中文翻译：

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行道树组合生态系统服务的变化可以指导可持续城市发展

摘要 城市绿化是促进城市可持续发展的重要战略。在没有大型新绿地的城市，路边种植树木被认为是一项重要的造林战略。然而，行道树组合所提供的生态系统服务在不同社会经济梯度上的差异尚未得到充分探索。我们检查了沿城市-郊区连续体的行道树组合提供的生态系统服务的这种变化。我们的发现如下。(1) 并非所有的生态系统服务都呈现出沿城市-郊区连续体增加的趋势。在城市化强度高的地区，行道树组合层面的一些生态系统服务，如空气净化和降雨拦截，表现突出。(2) 行道树组合的差异化特征呈现出多样化的生态系统服务趋势。行道树组合的结构特性，例如树木密度和年龄结构，可能是影响变化的关键因素。(3) 虽然行道树的密度可以部分弥补大型古树的损失，但保护这些树很重要，因为它们与关键的生态系统服务密切相关，例如总碳储存。为了最大限度地发挥行道树在促进城市可持续发展中的价值，多种生态系统服务之间的权衡应纳入总体规划过程和种植制度的调整中。树木密度和年龄结构等可能是影响变化的关键因素。(3) 虽然行道树的密度可以部分弥补大型古树的损失，但保护这些树很重要，因为它们与关键的生态系统服务密切相关，例如总碳储存。为了最大限度地发挥行道树在促进城市可持续发展中的价值，多种生态系统服务之间的权衡应纳入总体规划过程和种植制度的调整中。树木密度和年龄结构等可能是影响变化的关键因素。(3) 虽然行道树的密度可以部分弥补大型古树的损失，但保护这些树很重要，因为它们与关键的生态系统服务密切相关，例如总碳储存。为了最大限度地发挥行道树在促进城市可持续发展中的价值，多种生态系统服务之间的权衡应纳入总体规划过程和种植制度的调整中。