Abstract Detail



Bryology and Lichenology

Carvajal, Niko [1], Clark, Theresa [2], Stark, Lloyd [3], Coe, Kirsten [4].

Variation in carbon balance in the dryland biocrust moss Syntrichia caninervis along a natural precipitation in the Mojave Desert.

Dryland ecosystems account for over 40% of global land area and are projected to increase in aridity in the face of climate change. Biocrusts - communities of moss, lichen, and cyanobacteria - are critical to the function of dryland ecosystems, and mosses of the genus Syntrichia are keystone crust organisms in North America. Syntrichia mosses display a diversity of adaptations to dryland environments including desiccation tolerance: the ability to dry out completely and regain functioning following rehydration. Degrees of desiccation tolerance in Syntrichia can vary by both species and genotype based on climate and microhabitat conditions. To investigate how differences in microclimate and microhabitat affect desiccation tolerance within a species, we examined desiccated S. caninervis samples ex-situ from three sites along a precipitation gradient in the Sheep Creek Mountains, NV. We recorded carbon balance following rehydration (a functional trait related to desiccation tolerance) to investigate differences in desiccation tolerance. We observed variation in carbon balance as a function of the microclimate and microhabitat of field sites based on ambient precipitation, proximity to bushes or shrubs, and topographical aspect. The largest of these differences were between the low and high precipitation sites. We also found that, regardless of collection site, desiccated volume of S. caninervis tissue could be used to predict both the volume of water needed by moss to reach turgidity (r2 =0.67) as well as the photosynthetic volume of the turgid samples (r2 =0.90). Collectively, these results indicate potential suites of environmental variables that influence desiccation tolerance in this ecologically important species of dryland moss and offer insight into the variability of genotypic responses to hydration in the face of global change.


1 - Middlebury College, Biology, 14 Old Chapel Rd., Middlebury, VT, 05753-6004, United States
2 - University of Nevada Las Vegas
3 - University Of Nevada, Las Vegas, School Of Life Sciences, Las Vegas, NV, 89154, United States
4 - Middlebury College, Biology, 14 Old Chapel Rd., Box: 2911 Middlebury College, Middlebury, VT, 05753-6004, United States

Keywords:
bryophyte
climate change
Desert Ecology
Precipitation Gradient
desiccation tolerance.

Presentation Type: Oral Paper
Number:
Abstract ID:963
Candidate for Awards:A. J. Sharp Award


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