Net Assimilation Rate Determines the Growth Rates of 14 Species of Subtropical Forest Trees

Created at: 2019-10-09

Envisaged journal: PLosOne http://dx.doi.org/10.5061/dryad.5kb61

Envisaged date: 2016-02-17

Rationale

Growth rates are of fundamental importance for plants, as individual size affects myriad
ecological processes. We determined the factors that generate variation in RGR among 14
species of trees and shrubs that are abundant in subtropical Chinese forests. We grew
seedlings for two years at four light levels in a shade-house experiment. We monitored the
growth of every juvenile plant every two weeks. After one and two years, we destructively
harvested individuals and measured their functional traits and gas-exchange rates. After
calculating individual biomass trajectories, we estimated relative growth rates using nonlin-
ear growth functions. We decomposed the variance in log(RGR) to evaluate the relation-
ships of RGR with its components: specific leaf area (SLA), net assimilation rate (NAR) and
leaf mass ratio (LMR). We found that variation in NAR was the primary determinant of varia-
tion in RGR at all light levels, whereas SLA and LMR made smaller contributions. Further-
more, NAR was strongly and positively associated with area-based photosynthetic rate and
leaf nitrogen content. Photosynthetic rate and leaf nitrogen concentration can, therefore, be
good predictors of growth in woody species.

Datasets (1)

Calculated Authors

Xuefei Li Bernhard Schmid, Prof.

Data request state

Preparation Project Board Data Requests Finished