Widespread species of Phragmites australis has a high degree of
intraspecific variation in functional traits along external climatic and
environmental gradients. However, the underlying mechanisms of the
environmental gradient at regional scale on intraspecific variation and
adaptation strategies of species functional traits are still not well
understood. The leaf, stem and root traits of P. australis in lakeshore
wetlands of semi-arid and arid regions in the Inner Mongolia Plateau
were measured to reveal the variability of functional traits at regional
scales and the influencing factors, and to reveal the ecological
adaptation strategies of P. australis in different regions through plant
economic spectrum. The results showed that variation of functional
traits of P. australis had a significant latitudinal pattern.
Temperature determined the intraspecific variation of the functional
traits of P. australis, and the influence of soil properties was small.
Plant economic spectrum theory was also applicable to the functional
traits of various organs and whole plants of P. australis, and different
ecological adaptation strategies were confirmed across arid and
semi-arid regions. This study provides a new understanding of
intraspecific variation of functional traits of P. australis originates
from temperature-mediated climatic differences brought about by sampling
geographic locations, rather than the soil properties of the sampling
locations and the joint of climate and soil. The utilization and
assimilation of resources of P. australis were conservative in arid
regions, while in semi-arid regions it was an acquisition strategy.