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Summary Vegetative traits of plants can respond directly to changes in the environment, such as those occurring under climate change. That phenotypic plasticity could be adaptive, maladaptive, or neutral.We manipulated the timing of spring snowmelt and amount of summer precipitation in factorial combination and examined responses of specific leaf area (SLA), trichome density, leaf water content (LWC), photosynthetic rate, stomatal conductance and intrinsic water‐use efficiency (iWUE) in the subalpine herbIpomopsis aggregata. The experiment was repeated in three years differing in natural timing of snowmelt. To examine natural selection, we used survival, relative growth rate, and flowering as fitness indices.A 50% reduction in summer precipitation reduced stomatal conductance and increased iWUE, and doubled precipitation increased LWC. Combining natural and experimental variation, earlier snowmelt reduced soil moisture, photosynthetic rate and stomatal conductance, and increased trichome density and iWUE. Precipitation reduction reversed the mortality selection favoring high stomatal conductance under normal and doubled precipitation, and higher LWC improved growth.Earlier snowmelt is a strong signal of climate change and can change expression of leaf morphology and gas exchange traits, just as reduced precipitation can. Stomatal conductance and SLA showed adaptive plasticity under some conditions.
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Ecophysiological variables of common shrub and grass species during the growing season following simulated sandblasting trials at the Jornada Experimental Range, New Mexico, USA, 2018 and 2019
In this dataset, we report ecophysiological variables of contrasting perennial grass (Bouteloua eriopoda, Sporobolus airoides, and Aristida purpurea) and shrub (Prosopis glandulosa, Atriplex canescens, and Larrea tridentata) functional groups before and after a series of simulated sandblasting events with various intensities and frequencies. We hypothesized that grass species are more susceptible to the resulting "sandblasting" (i.e., abrasive damage by wind-blown particulates) than shrubs, thus contributing to the shift from grass to shrub dominance. To test this, we conducted a wind tunnel experiment at the USDA Jornada Experimental Range in 2018 and 2019 growing seasons. Potted plants were subjected to different levels of sandblasting in a novel portable wind tunnel, and plants’ ecophysiological responses including leaf gas exchange and nighttime leaf stomatal conductance were quantified. All tested plants were then grown in benign greenhouse conditions to investigate plant recovery post sandblasting. This dataset contains data about plant biomass and height, leaf chlorophyll content, leaf gas exchange, stomatal conductance, and water use efficiency (WUE) under the experimental treatments above. This study is complete.
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- Award ID(s):
- 2025166
- PAR ID:
- 10476774
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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