Are invasive woody plants released from ecophysiological constraints on photosynthetic capacity?
Knapp, Liza*,1, Fownes, James1, Harrington, Robin1, 1 University of Massachusetts – Amherst, Amherst, MA ABSTRACT- Invasive plant species may succeed in part due to release from tradeoffs that constrain the performance of native species. Photosynthetic capacity is generally constrained by interspecific tradeoffs between leaf N concentration and leaf mass per area (LMA). We compared interspecific and intraspecific trends in leaf physiology and morphology in four native and four invasive woody species planted in open and understory plots. Leaf N was positively correlated with mass-based, light-saturated net assimilation (Asat), both among and within species. Leaf N was consistently higher in invasives than in natives of similar life form and shade tolerance. We detected few significant differences in the Asat–leaf N relationship between invaders and their native counterparts. LMA and photosynthetic nitrogen use efficiency (PNUE) were negatively correlated among species but positively cor
