Title

Enhanced monsoon precipitation and nitrogen deposition affect leaf traits and photosynthesis differently in spring and summer in the desert shrub Larrea tridentata

Document Type

Article

Abstract

Leaf-level CO2 assimilation (Aarea) can largely be predicted from stomatal conductance (gs), leaf morphology (SLA) and nitrogen (N) content (Narea) in species across biomes and functional groups. The effects of simulated global change scenarios, increased summer monsoon rain (+H2O), N deposition (+N) and the combination (+H2O +N), were hypothesized to affect leaf trait-photosynthesis relationships differently in the short- and long-term for the desert shrub Larrea tridentata. During the spring, +H2O and +H2O +N plants had lower Aarea and gs, but similar shoot water potential (Ψshoot) compared with control and +N plants; differences in Aarea were attributed to lower leaf Narea and gs. During the summer, +H2O and +H2O +N plants displayed higher Aarea than control and +N plants, which was attributed to higher Ψshoot, gs and SLA. Throughout the year, Aarea was strongly correlated with gs but weakly correlated with leaf Narea and SLA. We concluded that increased summer monsoon had a stronger effect on the performance of Larrea than increased N deposition. In the short term, the +H2O and +H2O +N treatments were associated with increasing Aarea in summer, but also with low leaf Narea and lower Aarea in the long term the following spring.

Disciplines

Desert Ecology | Plant Biology

Publisher Citation

Barker, D. H., Vanier, C., Naumburg, E., Charlet, T. N., Nielsen, K. M., Newingham, B. A. and Smith, S. D. (2006), Enhanced monsoon precipitation and nitrogen deposition affect leaf traits and photosynthesis differently in spring and summer in the desert shrub Larrea tridentata. New Phytologist, 169: 799–808. doi: 10.1111/j.1469-8137.2006.01628.x