摘要
Aims Plant functional traits determine how plants respond to environmen-tal factors and influence ecosystem processes.Among them,root traits and analyses of relations between above and below-ground traits in natural communities are scarce.Methods we characterized a set of above-and below-ground traits of three dominant shrub species in a semiarid shrub-steppe that had contrasting leaf pheno-logical habits(deciduous,semideciduous and evergreen).We ana-lysed if there was coordination among above-and below-ground resource economics patterns:i.e.patterns of biomass allocation,construction costs and lifespan.Important Findings Above-and below-ground traits and their resource economics relations pointed to species-specific functional strategies to cope with drought and poor soils and to a species ranking of fast to slow whole-plant strategies in terms of resource uptake,biomass con-struction costs and turnover.The deciduous shrub,Proustia cunei-folia,had relatively deep and even distribution of roots,and high proportion of short-lived tissues of low C construction costs:it had high fine to coarse root and high leaf-to-stem biomass ratios,high specific leaf area(SLA),and stems of low wood density.This strat-egy allows Proustia to maximize and coordinate above-and below-ground resources uptake as long as the most limiting factor(water)is available,but at the cost of having relative high plant biomass turnover.The evergreen Porlieria chilensis,instead,displayed a more conservative and slow strategy in terms of resource econom-ics.It had~80%of the roots in the 40 cm topsoil profile,low pro-portion of fine compared with coarse roots and low leaf-to-stem ratios,low SLA and stems of high wood density,i.e.it invested in C costly tissues that,overall,persist longer but probably at the cost of having lower plant resource uptake rates.Traits in the semide-ciduous Adesmia bedwellii were in between these two functional extremes.Our results revealed high functional diversity and above-and below-ground complementarity in resource economics among these three codominant species in the Chilean coastal desert.
基金
C.A.was granted with a postdoctoral fellowship from the Institute of Ecology and Biodiversity with the financial support of contract(ICM P05-002)
This study was funded by Fondo Nacional de Desarrollo Científico y Tecnológico(1110228).