Intraspecific trait variation and species turnover mediate grazing impacts on above- and below-ground functional trait composition of plant communities

Although grazing has significant impacts on plant functional traits and community composition in grasslands, few studies have simultaneously explored how plant above- and below-ground traits and community functional composition respond to grazing.
Using a grazing manipulation experiment with seven levels of grazing intensity (0, 1.5, 3.0, 4.5, 6.0, 7.5, and 9 sheep ha-1) in the Inner Mongolia grassland, we partitioned the roles of intraspecific trait variation (ITV) and species turnover underlying the grazing induced changes in above- and below-ground functional trait composition of plant communities.  Six aboveground traits (i.e. plant height, plant aboveground biomass, plant density, leaf area, specific leaf area (SLA) and leaf density) and three root traits (average root diameter, ARD; specific root length, SRL; and root tissue density, RTD) of the first-, second- and third-order roots (1st-, 2nd-, and 3rd-) were measured at the plant individual level. 
At the community level,...