With the bulk of the global population now living in cities, creating a cool, green refuge through extensive urban forests is a priority. However, we are concerned that tree species currently growing in our cities may not tolerate future climates. Esperon-Rodriguez et al. (2024) recently presented an estimate of ‘climate risk’ for a given tree species in a given location using a climate safety margin, based on the difference between the current climate of that city and the realized climate niche of that tree species globally. We attempted to validate this method by relating safety margin estimates with hydraulic vulnerability, a key plant functional trait linked to tree species drought tolerance. However, we found no relationship and therefore caution against the use of climate-based, safety margin methods of assessing urban tree species suitability or climate risk without further context. To develop a robust method of validation, we suggest greater focus on establishing urban forest inventory and tree health data in future climate analogue cities.

中文翻译：

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评论： Esperon-Rodriguez 等人的“在城市规模绘制城市森林的气候风险地图”。


由于现在全球大部分人口居住在城市，因此通过广阔的城市森林创造一个凉爽的绿色避难所是当务之急。然而，我们担心目前生长在我们城市中的树种可能无法忍受未来的气候。Esperon-Rodriguez 等人（2024 年）最近根据该城市的当前气候与全球该树种的已实现气候生态位之间的差异，使用气候安全边际对给定地点的给定树种的“气候风险”进行了估计。我们试图通过将安全边际估计与水力脆弱性联系起来来验证这种方法，水力脆弱性是与树种耐旱性相关的关键植物功能性状。然而，我们发现没有关系，因此在没有进一步背景的情况下，不要使用基于气候的安全边际方法来评估城市树种适宜性或气候风险。为了开发一种强大的验证方法，我们建议在未来的气候模拟城市中更加注重建立城市森林清单和树木健康数据。