Micromorphological and physico-chemical analyses of cultural layers in the urban soil of a medieval city - A case study from Krakow, Poland

摘要

This study assessed the impact of human activity on the properties of urban soils and the formation of cultural layers (CLs) over several hundred years by examining the micromorphological, physical and chemical features of those soils. The study relied on a soil profile exposed during archaeological excavations carried out in the Main Market Square (MMS) of Krakow, Poland, in 2007. Two parts of the profile were distinguished. The upper section of the soil profile was composed of 13 cultural layers, while the base layer was composed of macroscopically unchanged natural soil. CLs with similar soil textures clearly differed from the natural horizons (NHs), exhibiting higher organic carbon (C-org), total nitrogen (N-t), CaCO3 and available phosphorus (P-Ol) levels. The ranges of CL C-org, N-t, CaCO3 and Pot levels are 14.3-118 g.kg(-1), 1.1-10.6 g.kg(-1). 10.5-79.0 g.kg(-1) and 163-510 mg.kg(-1), respectively, while NH levels are 039-5.5 g.kg(-1), 0.13-0.54 g.kg(-1), 1.2-2.5 g.kg(-1) and 50.1-214 mg.kg(-1), respectively. CLs were characterised by lower pH values compared to NHs. An A horizon Development Index (ADI) was used to assess the degree of advancement of pedogenesis in the different layers. Additionally, correlation coefficients between ADI and the P-Ol content, as well as between ADI and the C-org content, were calculated.