Effect of plateau pika disturbance on reproductive allocation of Kobresia pygmaea

Plateau pika (Ochotona curzoniae) disturbance induces the alteration of Kobresia pygmaea habitats in alpine meadows, and reproductive allocation is a main strategy for plants to adapt to altered habitats. A field survey was carried out to determine the effects of plateau pika disturbance on the reproductive allocation of K. pygmaea. This study showed that plateau pika disturbance significantly increased the total biomass, underground biomass, reproductive shoot-vegetative shoot ratio, and root-shoot ratio of K. pygmaea (P<0.05), while it decreased its aboveground biomass (P<0.05). In the disturbed areas, the total biomass and aboveground biomass of K. pygmaea increased initially, and then decreased with increasing intensity of disturbance. The reproductive shoot-vegetative shoot ratio of K. pygmaea decreased initially, and then increased, indicating that K. pygmaea allocated more resources to vegetative growth, to expand its population, when disturbance intensity increased from low disturbance to the appropriate disturbance intensity threshold. However, it allocated more resources to reproductive growth, to ensure population survival, when disturbance intensity was greater than the appropriate disturbance intensity threshold.