Urban soils are still insufficiently studied despite the relevance of their functions in the urban environment. The city of Santiago de Compostela (northwestern Spain) offers interesting opportunities for the study of urban soils because of its geological diversity and the variety of land use and vegetation. With the objective of increasing information about urban soils in Spain, we studied samples from 56 urban soils (0–20 cm) in this city, developed over different parent materials (granites, gneiss, schists, and amphibolites) and under several land uses (lawn areas, forested areas, urban allotment gardens, peri‐urban agricultural soils, and a green roof). The main physicochemical properties of the soils were analyzed, including bulk density, texture, pH, organic matter, cation exchange capacity, available P, and compounds of Fe and Al. The soils are coarse textured (dominant texture is sandy loam) and acidic (pH in water from 4.7 to 6.9), with moderate to high organic matter contents (13–137 g organic C kg⁻¹). Cation exchange capacity ranges from 9 to 48 cmol_c kg⁻¹, with Ca as the most abundant exchangeable cation in most soils. Overall, the soils do not show several of the common features of other urban soils, such as alkalinity, high bulk density, or large amounts of artifacts, and their composition is very similar to their natural counterparts in the region. The conservation of these soils with a low degree of artificialization is essential because they can provide a wide range of ecosystem services.

中文翻译：

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西班牙西北部圣地亚哥德孔波斯特拉市土壤的组成和化学性质

尽管城市土壤在城市环境中的功能具有相关性，但对土壤的研究仍然不足。圣地亚哥德孔波斯特拉市（西班牙西北部）由于其地质多样性以及土地利用和植被的多样性，为研究城市土壤提供了有趣的机会。为了增加有关西班牙城市土壤的信息，我们研究了该城市56种城市土壤（0-20厘米）的样品，这些样品是在不同的母体材料（花岗岩，片麻岩，片岩和角闪石）上以及几种土地用途下开发的（草坪区域，森林区域，城市分配花园，郊区农业土壤和绿色屋顶）。分析了土壤的主要理化性质，包括堆积密度，质地，pH，有机质，阳离子交换容量，有效磷以及铁和铝的化合物。^-1）。阳离子交换容量为9至48 cmol _c kg ^-1，其中Ca是大多数土壤中最丰富的可交换阳离子。总体而言，这些土壤没有表现出其他城市土壤的几个共同特征，例如碱度，高堆积密度或大量人工制品，并且其组成与该地区的自然相似。以低人工水平保护这些土壤至关重要，因为它们可以提供广泛的生态系统服务。