The Influence of Land Use on Seasonal Variation in Soil Properties, Microbial Activity, and Bioactive Acid Accumulation in Taraxacum officinale and Plantago major

(1) Background: Plantago major and Taraxacum officinale exhibit high tolerance to soil pollution and are recognised as bioindicators of soil quality. The objectives of the study were to investigate (i) the physicochemical and microbiological properties of rhizosphere soil beneath P. major and T. officinale in different land uses, (ii) the accumulation of elements, phenolic and organic acids in soil as well as in the plants, and (iii) the relationships between these parameters. (2) Methods: Samples were collected from three locations: the sediment retention area, the post-mining area, and the recreational area in May and September. (3) Results: Significant seasonal differences were observed in soil parameters, enzymatic activity, microbial abundance, and the contents of elements, organic acids, and phenolic acids between plant species and sampling areas, with changes reaching several hundred per cent. Correlations were found between dehydrogenase and organic matter, S, Al, Co, Cr, Fe, K, Mg, Mn, P; and phosphatases and Al, Co, Cr, Fe, Mg, Ni, and Mn; as well as between total phenolic content and phosphatases; syringic acid and dehydrogenase; and alkaline phosphatase and lactic and citric acids. (4) Conclusions: The results suggest that plant–soil interactions, in relation to land use, influence rhizosphere biochemistry, thereby impacting soil health and supporting ecosystem recovery.