Spatial Heterogeneity of Urban Soils: The Case of the Beijing Metropolitan Region, China

QIZHENG MAO, GANLIN HUANG, ALEXANDER BUYANTUEV, JIANGUO WU, SHANGHUA LUO, AND KEMING MA 3.1 INTRODUCTION Soil, as the component of urban green spaces (UGS) (Setälä et al. [2013]), plays a pivotal role in maintaining urban ecosystem services, such as biodiversity maintenance, water resources protection, microclimate regulation, carbon sequestration, food production, and fulfillment of cultural or recreational needs (Lovell and Taylor [2013]; Neil et al. [2014]; Wu [2014]). Urban soils are large pools of carbon, nitrogen, and other elements, serving as the foundation of urban ecosystems by supporting plant growth and sustaining biogeochemical cycles (Pouyat et al. [2002]). Quantifying soil properties and understanding soil conditions are essential for assessing ecosystem services provided by UGS and detecting pollution in UGS.