DOI: 10.5061/dryad.r98jq6j
title: Data from: Complementary responses of morphology and physiology enhance the stand-scale production of a model invasive species under elevated CO2 and nitrogen

description: 1. Elevated atmospheric carbon dioxide (eCO2) concentrations and nitrogen
 (N) enrichment are known to enhance plant productivity and invasion.
 However, the implications of their interactive effects for plant
 productivity are not well understood, especially at the stand scale,
 presumably because morphological and physiological responses to these
 global change factors are rarely studied together in the field or assessed
 at the stand-level. 2. We first determined how leaf-level morphological
 and physiological traits responded to factorial combinations of ambient
 and elevated CO2 and N. We collected trait data from the model invasive
 species Phragmites australis (common reed) that were measured over three
 years in a long-term global change field experiment. We then combined the
 trait data and additional descriptions of P. australis canopies in a
 simulation model of carbon assimilation to determine how morphology and
 physiology contribute to P. australis’ stand scale productivity. 3. At the
 leaf level, we found that light-saturated rates of photosynthesis were
 strongly stimulated by eCO2 (37%) and that this effect was enhanced by
 increasing salinity. N had a smaller effect (17% stimulation) on
 physiological responses than eCO2, but leaf morphological traits responded
 primarily to N; plant height increased by 27% and leaf area increased by
 47%. 4. Stand scale simulations demonstrated that that morphological and
 physiological adjustments induced approximately additive responses when P.
 australis experienced both eCO2 and N enrichment. The simulations also
 indicated that morphological changes (which were primarily associated with
 canopy size) influenced stand scale carbon assimilation more than
 physiological changes. Moreover, 97% of the N response was due to changes
 in morphology, whereas 62% of the eCO2 response was caused by
 physiological shifts. 5. Our analysis indicates that morphological and
 physiological trait responses to elevated CO2 and nitrogen are likely to
 enhance the productivity of P. australis in complementary ways,
 potentially accelerating its invasion in North America. Furthermore, our
 data suggest that changes in morphological traits may have a greater
 influence on carbon gain than leaf-level physiology under near-future
 environmental conditions. Our study also highlights the importance of
 accounting for both morphological and physiological responses when
 attempting to infer global change responses from leaf-level data.
description: ReadmeVariable definitions for
 the datasets that accompany: Mozdzer & Caplan (2018) Complementary
 responses of morphology and physiology enhance stand scale production of a
 model invasive species under elevated CO2 and nitrogen.Light curve
 dataCharacteristic
 measurements and fitted parameters from photosynthetic light response
 curvesMozCap_LightCurveData.csvCulm height dataHeights of all Phragmites australis culms (aboveground stems) in open-top chambers during censusesMozCap_CulmHeightData.csvSpecific leaf area dataAreas, masses, and specific areas for collected leavesMozCap_SLAData.csvLeaf morphology dataAreas, lengths, and widths of leaves collected from three plants per chamberMozCap_LeafMorphData.csvChlorophyll index dataSpectral-based measurement of chlorophyll content measured in leavesMozCap_ChlIndexData.csvStomatal density dataNumber of stomata counted per unit area from leaf peelsMozCap_StomDensityData.csvStomatal dimension dataLengths, widths, and areas of stomata identified in leaf peelsMozCap_StomDimensionsData.csvAnnual GPPOutput from runs of a simulation model describing stand level gross primary productivityMozCap_AnnualGPPData.csv