Urban greenspace has gained considerable attention during the last decades because of its relevance to wildlife conservation, human welfare, and climate change adaptation. Biodiversity loss and ecosystem degradation worldwide require the formation of new concepts of ecological restoration and rehabilitation aimed at improving ecosystem functions, services, and biodiversity conservation in cities. Although relict sites of natural and semi-natural ecosystems can be found in urban areas, environmental conditions and species composition of most urban ecosystems are highly modified, inducing the development of novel and hybrid ecosystems. A consequence of this ecological novelty is the lack of (semi-) natural reference systems available for defining restoration targets and assessing restoration success in urban areas. This hampers the implementation of ecological restoration in cities. In consideration of these challenges, we present a new conceptual framework that provides guidance and support for urban ecological restoration and rehabilitation by formulating restoration targets for different levels of ecological novelty (i.e., historic, hybrid, and novel ecosystems). To facilitate the restoration and rehabilitation of novel urban ecosystems, we recommend using established species-rich and well-functioning urban ecosystems as reference. Such urban reference systems are likely to be present in many cities. Highlighting their value in comparison to degraded ecosystems can stimulate and guide restoration initiatives. As urban restoration approaches must consider local history and site conditions, as well as citizens’ needs, it may also be advisable to focus the restoration of strongly altered urban ecosystems on select ecosystem functions, services and/or biodiversity values. Ecosystem restoration and rehabilitation in cities can be either relatively inexpensive or costly, but even expensive measures can pay off when they effectively improve ecosystem services such as climate change mitigation or recreation. Successful re‐shaping and re-thinking of urban greenspace by involving citizens and other stakeholders will help to make our cities more sustainable in the future.

在过去的几十年中，城市绿地与野生动植物保护，人类福祉和适应气候变化有关，因此受到了相当大的关注。世界范围内的生物多样性丧失和生态系统退化需要形成旨在恢复城市生态系统功能，服务和生物多样性保护的新的生态恢复和恢复概念。尽管在城市地区可以找到自然和半自然生态系统的遗迹，但是大多数城市生态系统的环境条件和物种组成都发生了很大变化，从而引发了新型和混合生态系统的发展。这种生态新颖性的结果是缺乏（半）自然参考系统可用于确定恢复目标和评估城市地区的恢复成功。这阻碍了城市生态恢复的实施。考虑到这些挑战，我们提出了一个新的概念框架，通过为不同层次的生态新颖性（即历史性，混合性和新型生态系统）制定恢复目标，为城市生态恢复和恢复提供指导和支持。为了促进新型城市生态系统的恢复和恢复，我们建议使用物种丰富且功能良好的成熟城市生态系统作为参考。这样的 为了促进新型城市生态系统的恢复和恢复，我们建议使用已建立物种丰富且功能良好的城市生态系统作为参考。这样的 为了促进新型城市生态系统的恢复和恢复，我们建议使用物种丰富且功能良好的成熟城市生态系统作为参考。这样的城市参考系统很可能会出现在许多城市。与退化的生态系统相比，突出它们的价值可以刺激和指导恢复计划。由于城市恢复方法必须考虑当地历史和遗址条件以及市民的需求，因此，将强烈变化的城市生态系统的恢复重点放在精选的生态系统功能，服务和/或生物多样性价值上也是可取的。城市中的生态系统恢复和恢复可能相对便宜，也可能成本较高，但是当有效地改善生态系统服务（如减缓气候变化或娱乐活动）时，即使是昂贵的措施也可以取得回报。通过让公民和其他利益相关者参与，成功重塑和重新思考城市绿地，将有助于使我们的城市在未来更具可持续性。