Article

The influence of soil on plant cover was investigated in two different soil types, on limestone and on phyllite, in the Coimbra peri-urban area. Two areas were selected in each soil type. Soil was analysed for colour, pH, electrical conductivity, moisture, organic matter content, mineralogy, texture and chemical composition. Floristic composition was assessed and abundance was calculated using DAFOR methodology. Data were statistically analysed in Canoco for Windows 4.5. The two soil types have distinct texture and distinct mineralogical, physical and chemical properties. Soil on limestone had pH, electrical conductivity and moisture content higher than soil on phyllite; the latter had higher organic matter content. Soil on limestone had silt clay loam texture and the most abundant minerals were calcite and quartz. The texture of soil from phyllite is sandy loam, loam and silt loam and the most abundant minerals were quartz and mica. Also, most common oxides and trace elements are different. A total of 288 taxa in 61 families (Fabaceae, Asteraceae, and Poaceae are predominant) were identified, showing the enormous diversity of the peri-urban vegetation of Coimbra. A clear distinction was found between the vegetation of the areas of limestone and phyllite; the main environmental factors influencing the ordering of species are pH, mineralogy and anthropic impact.