Drought stress and dominant removal: effects on flowering synchronization
Under the high-water level condition (control), we recorded zero synchrony in RA within the community of subordinate species and asynchrony across the entire species community (Fig. 2). Conversely, we observed a shift towards synchronous reproductive allocation under both drought stress treatments. The effect of dominant removal was not significant for the RA synchrony of subordinate species (despite an apparent trend for their higher synchrony in the low-water treatment). Pairwise correlations showed the synchronous RA response (positive correlation) only for the subordinate species and mostly for C. elongata and D. cespitosa (Fig. 3). C. canescens synchronised flowering with other subordinate species only in a permanent low-water treatment when the dominant species was removed.C. elata showed a negative correlation in RA with all species in all treatments (Fig. 3).
Intraspecific RA for tussock species was also highly synchronous in the high-water treatment (control) (Fig. 4). Individuals of C. elongata even increased their RA synchrony in both drought stress treatments. The weak trend suggests that dominant removal under drought stress reduced synchrony in this species. We found no such response inD. cespitosa . In contrast, individuals of C. elata decreased their RA synchrony under the permanent drought stress treatment.