Repeated drying and rewetting differently affect abiotic and biotic soil phosphorus (P) dynamics in a sandy soil: A 33P soil incubation study

Soil drying and rewetting (DRW) events are expected to occur at higher frequencies because of alterations in climate patterns. Readily extractable inorganic microbial soil phosphorus (P) pools may be affected due rapid changes water availability. We aimed determine how P dynamics by repeated DRW using a sandy grassland that regularly experiences DRW. In laboratory incubation study, the was exposed three cycles, with each cycle consisting two-day phase, three-day dryness phase four-day moist after rewetting. The indicators abiotic processes (P sorption) biotic (respiration, abundance, potential phosphatase enzyme activities) were determined together water-extractable P, resin-extractable 33P-labelled soil. During first cycle, reduced half accompanied concomitant but not equivalent increase slight as well delayed P. Thus, increases explained released during also occupying sorption sites, thereby decreasing sorption. Changes 33P-isotopic composition same time suggested microorganisms did respond homogenously treatment indicated an increased mineralisation previously unavailable organic compounds. However, second third only activities treatment, whereas all other parameters remained similar values constant treatment. effects on appeared affect more long-lastingly, most quickly adjusted conclude current concepts suggesting mobility towards environmental compartments should consider equally case short repetition incidences.