Assessing the Interannual Variation in Vegetative Response to Climate in Spring Valley, NV Lorenzo Apodaca 2/13/12

Effects of climate change Lengthening of growing season Reduction in total winter snow pack Increase in water stress Changes in species composition Shifts in plant ecotones Spread of invasive species Animate each term Associate each with a picture

Spring Valley Directly west of GBNP (NE NV) Mainly mixed shrubland Location of one of the towers in Snake Range transect Perhaps skip most of this information and only show a slide mentioning the relation to the Snake transect

Linking plant growth response to past climate variability Goal : Establish empirical relationship between big sagebrush growth ring indices and remotely-sensed NDVI Linking plant growth response to past climate variability Provides a direct link between RS measurements of relative plant health status to a measure of plant productivity Relationship between wood development and seasonal precipitation

119 stems from within the valley Sample collection complete

Stem Stats Avg. ring count = 45 (s = 14) Max. count = 77 Min. count = 22 60% of stems date up to 1970

Skeleton Plot 1974 1989 1996 2007 1959 2002

Average growing season NDVI

Future Work Ring indices of all 128 sagebrush stems samples and sites Requires accurate dating of all stem rings Determine ring signal beyond the site level Examine relationship between ring indices and NDVI Between growth/development and climate

Acknowledgements UNLV Advisory Committee Devitt Lab Dr. Dale Devitt Dr. Lynn Fenstermaker Dr. Stan Smith Dr. Paul Schulte Devitt Lab Lena Wright Amanda Wagner Brian Bird Special thanks Fred Landau Ely BLM Funded by NSF EPSCoR seed grant

Devitt et al, Ecohydrology 2010.

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