Many methods have been applied to quantify urban ecosystem services (UESs) in the past two decades. Timely reviews of UES assessment methods are necessary for tracking the methodological progress and identifying research gaps. In this study, we systematically analyzed 862 to reveal the overall trend of quantitative studies of UESs, the types of ecological structures and UESs assessed in those studies, and the main equations and parameters used. We found a rising trend of quantitative studies of UESs, accelerating after 2015. Large-size and publicly-owned ecological structures and regulating services were assessed the most frequently. We identified 1,130 equations and 1,190 parameters. Simple methods and equations were used more regularly than complex ones. Values for around 30% of parameters were taken from published papers, while the sources or the values were not specified for about 40% and 20% of all parameters, respectively. The remaining 10% were derived from field measurements and other sources. Based on our findings, we recommend building an open database of quantitative methods, testing the suitability of existing methods for urban environments, developing new methods specifically designed for urban areas, and increasing the transparency of reported methods.

中文翻译：

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城市生态系统服务量化方法综述


在过去的二十年里，已经应用了许多方法来量化城市生态系统服务 （UES）。及时审查 UES 评估方法对于跟踪方法学进展和确定研究差距是必要的。在这项研究中，我们系统地分析了 862 个，以揭示 UES 定量研究的总体趋势、这些研究中评估的生态结构和 UES 的类型，以及使用的主要方程和参数。我们发现 UES 定量研究呈上升趋势，在 2015 年后加速。对大型和公有生态结构和调节服务的评估最频繁。我们确定了 1,130 个方程和 1,190 个参数。简单的方法和方程式比复杂的方法和方程式更常用。大约 30% 的参数值取自已发表的论文，而大约 40% 和 20% 的参数分别没有指定来源或值。其余 10% 来自现场测量和其他来源。根据我们的研究结果，我们建议建立一个开放的定量方法数据库，测试现有方法对城市环境的适用性，开发专门为城市地区设计的新方法，并提高报告方法的透明度。