Resource Regulation of the Regrow Capacity of Plants in Alpine Heaths: Factorial Experiment

The regrowth of the aboveground biomass of certain plant species after complete or partial defoliation in highlands can depend on competition with neighboring plants, as well as on the level of availability of soil resources, primarily mineral nutrients (especially N and P). A 3-year full-factorial experiment on the effect of three defoliation regimes (control and single and double mowing at the soil level per season), enrichment of soil with N and P, and removal of neighboring plants (competition reduction) on the shoot number and aboveground biomass of three plant species (Anemone speciosa, Festuca ovina, and Oxytropis kubanensis) in alpine heaths was carried out (in total, 12 variants in 10 replications). It is shown that the removal of competing vegetation in low-productive communities of alpine heaths does not contribute to the biomass recovery after defoliation, unlike the addition of NP fertilizers. The regrow of a nitrogen-fixing legume did not depend on the availability of soil resources.