Abstract Using local and recycled materials is a sustainable way to establish a vegetated roof. In order to understand how the roof ecosystem functions and returns ecosystem services, it is important to study vegetation, soil organisms and runoff quality. We established a vegetated roof experiment based on a substrate containing lightweight crushed concrete, an alkaline side product from a concrete factory, mixed with compost. This five-year experiment in southern Finland tested how planting method (pre-grown vegetation mats vs. pot planting), compost content (20% vs. 40%, fresh volume), and substrate depth affect the cover and diversity of plants, the abundance of soil animals and the quality of runoff. Although the substrate had a high pH (7.3–11.8), many vascular plants were able to survive and establish viable populations. The planting method had a strong effect on plant diversity and the cover of individual species because the vegetation mats became dominated by the invasive, non-native Phedimus hybridus. Establishment with pot plants in turn provided bare ground that was colonised by spontaneous non-invasive species. This resulted in higher diversity, and a more even distribution of species. The amount of compost had only a weak impact on vegetation, whereas high pH generally reduced plant abundance and diversity. The concentrations of total phosphorus and total nitrogen in runoff were low as compared to values reported from many other vegetated roofs, were not affected by compost content and decreased over time. In summary, the high-pH substrate based on recycled materials is an environmentally responsible choice, suitable for a wide variety of plants, even rare and endangered species.

中文翻译：

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植被屋顶的碱性栖息地？具有碎混凝土基底的植被屋顶的生态系统动力学

摘要 使用当地和回收材料是建立植被屋顶的可持续方式。为了了解屋顶生态系统的功能和恢复生态系统服务的方式，研究植被、土壤生物和径流质量非常重要。我们建立了一个植被屋顶实验，该实验基于包含轻质碎混凝土（混凝土工厂的碱性副产品）与堆肥混合的基材。这项在芬兰南部进行的为期五年的实验测试了种植方法（预先种植的植被垫与盆栽种植）、堆肥含量（20% 与 40%，新鲜量）和基质深度如何影响植物的覆盖度和多样性，丰富的土壤动物和径流质量。尽管基质的 pH 值很高（7.3-11.8），但许多维管植物能够存活并建立可存活的种群。种植方法对植物多样性和单个物种的覆盖率有很大影响，因为植被垫被入侵的非本地 Phedimus 杂种所支配。反过来，盆栽植物的建立提供了被自发的非入侵物种定殖的裸露地面。这导致更高的多样性和更均匀的物种分布。堆肥量对植被的影响很小，而高 pH 值通常会降低植物的丰度和多样性。与许多其他植被屋顶报告的值相比，径流中的总磷和总氮浓度较低，不受堆肥含量的影响，并随着时间的推移而下降。总之，基于回收材料的高 pH 底物是一种对环境负责的选择，适用于多种植物，