Physiological Response of Southern Appalachian High-Elevation Rock Outcrop Herbs to Reduced Cloud Immersion

UNCA Author/Contributor (non-UNCA co-authors, if there are any, appear on document)
Katherine Culatta, Student (Creator)
University of North Carolina Asheville (UNCA )
Web Site:
Jonathan Horton

Abstract: Cloud immersion experienced by high-elevation rock outcrop plants reduces the leaf-to-air vapor pressure deficit (VPD), decreasing transpirational water loss. Frequent cloud immersion might ameliorate water stress in shallow soil outcrop communities, increasing water use efficiency and growth. Current climate pattern predictions propose that Southern Appalachian cloud immersion frequency will decrease, potentially increasing water stress in rock outcrop plant populations. In this experiment, outcrop specialists Hydatica petiolaris (cliff saxifrage) and Solidagosimulans (granite dome goldenrod) were grown in microcosms simulating current, reduced, and absent cloud immersion. Light saturation point and water use efficiency (WUE) increased, and transpiration decreased with decreasing immersion treatment duration. Root mass, root to shoot ratio, and specific leaf mass were greatest in thereduced immersion treatment. Simulated non-immersed conditions resulted in higher VPD, photosynthetic rate, transpiration, and lower WUE across treatments. Results indicate phenotypic plasticity in response to immersion duration for some physiological parameters, suggesting the ability of these plants to acclimate to changing climatic conditions.

Additional Information

UNC Asheville - Journal of Undergraduate Research
Language: English
Date: 2013
cloud immersion, high-elevation, rock outcrop herbs

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