Dynamics of soil carbon, nitrogen, and phosphorus in calcareous soils after land-use abandonment – A chronosequence study

Abstract

The objective of this study was to investigate changes in soil total organic C (TOC), total nitrogen (TN), phosphorus (P) fractions, and microbial community structure during secondary succession after abandonment of vineyards on calcareous soils. Two chronosequences covering 200 years and differing in aspect and slope were established in Hungary, and the upper 10 cm of the mineral soils were studied. We found strong increases in TOC concentrations after land-use abandonment, especially at the south-exposed sites. The TOC/TN ratio increased by a factor of 1.3 in the south-west exposed chronosequence and by a factor of 1.6 in south exposed chronosequence. The concentration of labile P (NaHCO3-extractable P) diminished during the first 50 years after land-use abandonment, leading to low P availability at the later stages of the succession. The total organic P (TOP) concentration increased during the first 40 years after abandonment. At the later stages of succession, TOP concentrations decreased again, while the ratio of TOC/TOP increased continuously over 200 years. The ratio of arbuscular-mycorrhizal-fungi-to-bacteria (AMF/bacteria) increased strongly during the first decade after abandonment of the vineyards. Our study indicates that impacts of former cultivation on secondary ecosystems persisted for more than a century, and that especially P concentrations showed long lasting legacy effects.