Abstract Detail

Life without water: evolution and adaptation of xeric plants

DeFalco, Lesley [1], Scoles-Sciulla, Sara [1], Shryock, Daniel [2], Custer, Nathan [3], Schwinning, Susan [3], Jasinski, Briana [1], Esque, Todd [1].

Ecological restoration of disturbed desert shrublands through an understanding of local adaptation in native species.

Large-scale disturbances in western arid lands resulting from wildfires and burgeoning renewable energy development are driving the need to rehabilitate natural communities and halt further degradation. Ecological restoration aims to replace damaged vegetation using locally sourced seeds, yet in practice suitable collections may be unavailable in the quantities necessary for large scale restoration efforts. Seed sources targeted for use in ecological restoration are typically matched to current precipitation and temperature patterns but may not persist over long time scales due to increasingly hotter and drier conditions that are predicted for the arid West. Multiple common gardens distributed across the Mojave Desert ecoregion are testing whether measures of temperature and aridity (mean annual temperature, Tmax, Tmin, mean annual precipitation, summer precipitation, winter precipitation, coefficient of variation in precipitation) related to adaptive genetic variation across the ecoregion explain differences in plant performance among seed sources for key native restoration species. The drought-deciduous desert globemallow (Sphaeralcea ambigua) is often used in revegetating degraded low and mid-elevation desert shrublands that support habitat for sensitive wildlife and diverse pollinators in the ecoregion. Nursery-raised seedlings representing 11 seed sources across the Mojave Desert were planted into common gardens representing warm/dry, cool/wet, and intermediate temperature and precipitation gradients. While the majority of sources survived in the cool/wet and intermediate gardens, sources originating from sites with cooler mean annual temperatures had lower initial survival growing in the warm/dry garden in particular. These interactive effects on survival between seed source and garden are discussed in the context of tradeoffs between plant growth and phenology. Our approach of linking environmental and genetic variability with performance traits in multiple common gardens aims to mitigate the degradation of arid lands by establishing plant populations that are resilient in the face of current restoration challenges and future climate variability.

1 - US Geological Survey, Western Ecological Research Center, Henderson, NV, 89074, USA
2 - US Geological Survey, Western Ecological Research Center, Sacramento, CA, 95819, USA
3 - Texas State University, San Marcos, Department of Biology, San Marcos, TX, 78666, USA

Keywords:
desert
Sphaeralcea
local adaptation
Mojave
conservation and restoration
climate change
multiple common gardens.

Presentation Type: Symposium Presentation
Session: SYM7, Life without water: evolution and adaptation of xeric plants
Location: Tucson I/Starr Pass
Date: Wednesday, July 31st, 2019
Time: 2:15 PM
Number: SYM7003
Abstract ID:1051
Candidate for Awards:None