Abstract：
Nature-based solutions may actively reduce hydro-meteorological risks in urban areas as a part of climate change adaptation. However, the main reason for the increasing uptake of this type of solution is their many benefits for the local inhabitants, including recreational value. Previous studies on recreational value focus on studies of existing nature sites that are often much larger than what is considered as new NBS for flood adaptation studies in urban areas. We thus prioritized studies with smaller areas and nature types suitable for urban flood adaptation and divided them into four common nature types for urban flood adaptation: sustainable urban drainage systems, city parks, nature areas and rivers. We identified 23 primary valuation studies, including both stated and revealed preference studies, and derived two value transfer functions based on meta-regression analysis on existing areas. We investigated trends between values and variables and found that for the purpose of planning of new NBS the size of NBS and population density were determining factors of recreational value. For existing NBS the maximum travelling distance may be included as well. We find that existing state-of-the-art studies overestimate the recreational with more than a factor of 4 for NBS sizes below 5 ha. Our results are valid in a European context for nature-based solutions below 250 ha and can be applied across different NBS types and sizes.
摘要：
作为适应气候变化的一部分，基于自然的解决方案可以积极减少城市地区的水文气象风险。然而,越来越多地采用这种解决方案的主要原因是它们对当地居民的许多好处，包括娱乐价值。以前关于娱乐价值的研究侧重于对现有自然地点的研究，这些地点通常比被认为是城市地区洪水适应研究的新NBS大得多。因此，我们优先考虑适合城市洪水适应的较小区域和自然类型的研究，并将其分为四种常见的城市洪水适应自然类型：可持续城市排水系统，城市公园,自然区域和河流。我们确定了23项主要评估研究，包括陈述性和揭示性偏好研究，并基于对现有地区的元回归分析得出了两个价值传递函数。我们调查了值和变量之间的趋势，发现为了规划新的NBS，NBS的大小和人口密度是休闲价值的决定因素。对于现有NBS,也可以包括最大行进距离。我们发现，对于NBS大小低于5公顷的情况，现有的最新研究高估了娱乐性，超过4倍。我们的结果在欧洲范围内适用于250公顷以下的基于自然的解决方案，并且可以应用于不同的NBS类型和大小。
