Aims Effects of climate change,especially changes in temperatures and precipitation patterns,are particularly pronounced in alpine regions.In response,plants may exhibit phenotypic plasticity in key functional traits ...Aims Effects of climate change,especially changes in temperatures and precipitation patterns,are particularly pronounced in alpine regions.In response,plants may exhibit phenotypic plasticity in key functional traits allowing short-term adjustment to novel conditions.However,little is known about the degree of pheno-typic plasticity of high elevation species relative to mid elevation congeners.Methods We transplanted 14 herbaceous perennial species from high eleva-tion into two common gardens(1050 and 2000 m.a.s.l.)in the Swiss Alps,and we examined plastic responses in key functional traits to changes in temperature and soil water availability.This design was replicated with 14 congeneric species from mid elevation to assess if the degree of phenotypic plasticity differs between mid and high elevation species.Survival was assessed across two growing seasons,while aboveground biomass and specific leaf area(SLA)were measured after the first growing season,and biomass alloca-tion to belowground and reproductive structures after the second.Moreover,a phenotypic plasticity index was calculated for the func-tional traits to compare the degree of plasticity between mid and high elevation species.Important Findings Aboveground biomass was higher in mid elevation species relative to high elevation congeners in all treatments,yet decreased for both with elevation and drought.Similarly,SLA decreased with elevation and drought.Root mass fraction(RMF)was generally higher in high ele-vation species,and decreased with drought at the lower site.Drought increased the allocation to reproductive structures,especially when plants were grown at their elevation of origin.Interestingly,no differ-ence was found in the degree of phenotypic plasticity averaged across mid and high elevation species for any of the studied functional traits.These results indicate that phenotypic plasticity in the focal traits did not depend on the elevation of origin of the species.Plasticity was not related to environmental heterogeneity,nor constrained by selective pressures at high elevation.However,both species groups showed a remarkable capacity for short-term acclimation to a prospective cli-mate through rapid adjustments in key functional traits.展开更多
基金This work was supported by the Swiss National Science Foundation(3100A-135611)to J.Stöcklin.
文摘Aims Effects of climate change,especially changes in temperatures and precipitation patterns,are particularly pronounced in alpine regions.In response,plants may exhibit phenotypic plasticity in key functional traits allowing short-term adjustment to novel conditions.However,little is known about the degree of pheno-typic plasticity of high elevation species relative to mid elevation congeners.Methods We transplanted 14 herbaceous perennial species from high eleva-tion into two common gardens(1050 and 2000 m.a.s.l.)in the Swiss Alps,and we examined plastic responses in key functional traits to changes in temperature and soil water availability.This design was replicated with 14 congeneric species from mid elevation to assess if the degree of phenotypic plasticity differs between mid and high elevation species.Survival was assessed across two growing seasons,while aboveground biomass and specific leaf area(SLA)were measured after the first growing season,and biomass alloca-tion to belowground and reproductive structures after the second.Moreover,a phenotypic plasticity index was calculated for the func-tional traits to compare the degree of plasticity between mid and high elevation species.Important Findings Aboveground biomass was higher in mid elevation species relative to high elevation congeners in all treatments,yet decreased for both with elevation and drought.Similarly,SLA decreased with elevation and drought.Root mass fraction(RMF)was generally higher in high ele-vation species,and decreased with drought at the lower site.Drought increased the allocation to reproductive structures,especially when plants were grown at their elevation of origin.Interestingly,no differ-ence was found in the degree of phenotypic plasticity averaged across mid and high elevation species for any of the studied functional traits.These results indicate that phenotypic plasticity in the focal traits did not depend on the elevation of origin of the species.Plasticity was not related to environmental heterogeneity,nor constrained by selective pressures at high elevation.However,both species groups showed a remarkable capacity for short-term acclimation to a prospective cli-mate through rapid adjustments in key functional traits.
