Presentation on theme: "Remote Sensing Grassland Phenology in the Greater Yellowstone Ecosystem: Biophysical Correlates, Land Use Effects and Patch Dynamics November 28 th, 2012."— Presentation transcript:
Remote Sensing Grassland Phenology in the Greater Yellowstone Ecosystem: Biophysical Correlates, Land Use Effects and Patch Dynamics November 28 th, 2012 Nathan Piekielek
Phenology in Ecology Population dynamics and migration – Boone et al. 2006; Andreo et al. 2008 Spatial patterns of plant, bird and other diversity – Phillips et al. 2008; Nightingale et al. 2008 Fuel accumulation and drying – Westerling 2006; Littell et al. 2009 Detection of forest insect outbreak and recovery – deBeurs and Townsend 2008; Spruce et al. 2011 Nutrient cycling – Potter 2001; Risch and Frank 2010 Biological response to climate change – Myneni et al. 1997; Cleland et al. 2007 Integrated analyses with hydrologic cycle – Cayan 2001; Sun et al. 2008
Jan 17Oct 16May 9 Jul 28 Photo credit: Bill Berg, CoolWorks.com METRICNAMEINTERPRETATION SOSStart of SeasonStart of the growing season; green-up EOSEnd of SeasonEnd of the growing season; senescence MAXMaximum NDVI Combination of peak biomass and greenness INDVIIntegrated NDVIEstimate of total annual productivity
Research Questions 1.What are the biophysical correlates and likely drivers of grassland LSP in the GYE? a)How well do correlates predict LSP across the study- area? 2.How does land use modify grassland LSP from its natural biophysical state? 3.What are the seasonal patch- dynamics of green/growing grasslands in the study area?
Biophysical Correlates SRAD outer envelope control on timing Water or VPD in every model except SOS Temp. only in SOS – Impact of warming mediated by seasonal water-balance Influence of snow-dynamics is spatially-variable EOS is not captured well by models SNOWMELT SOS
Methods 1.Develop land use map 2.Apply biophysical models of natural LSP 3.Compare modeled natural LSP to observed actual LSP under different land uses
SOS EOS MAX INDVI Urb (n=9)Suburb (n=20) Exurb (n=39) Rur (n=51) Ag (n=155)
Ecological Implications (Mckenzie 2001) Banff, Alberta Landscape context for ungulate preference for private lands that has been observed by others (Thompson and Henderson 1998) Suggests future wildlife management challenges in GYE? Future modification and ecological impacts of land use are highly dependent on aesthetic preferences and values of future residents (Buyantuyev and Wu 2009)
Patch Dynamics Late-season important time for ungulates to graze green forage – weight gain, reproduction etc. EARLY SEPT. CURRENT
Implications 5 degree C growing season temperature increase EARLY SEPT. FUTURE 15 day earlier EOS on ave. 67% reduction in Sept. green forage area
Implications Climate and land use change in tandem: – Late-season green patches are almost exclusively on private lands – Migration a threatened ecological process in GYE? – What are the management options? GREEN FORAGE IN STUDY-AREA EARLY SEPT
Funding 1) NASA Applications Program 2) Montana Institute on Ecosystems Climate Datasets provided by: 1) Forrest Melton and the NASA Ecological Forecasting Laboratory: Landscape Biodiversity Laboratory http://ecocast.arc.nasa.gov/
Your consent to our cookies if you continue to use this website.