Climate Change and Biodiversity in Ecosystems of Eastern Washington. Climate Change and Biodiversity in Ecosystems of Eastern Washington

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1 Climate Change and Biodiversity in Ecosystems of Eastern Washington Jim Evans To preserve the plants, animals and natural communities that represent the diversity of life on Earth by protecting the lands and waters they need to survive. Climate Change and Biodiversity in Ecosystems of Eastern Washington Overview of major habitat types Effects of increasing temperature Effects of altered atmospheric chemistry (C, N) Interactions Strategies East Cascades Columbia Plateau Temperature and moisture gradients across the Cascades Dry conifer forests (Franklin & Dyrness 1973) Montane forest Dry forest Shrubsteppe Ponderosa pine White-headed headed woodpecker

2 Natural disturbance regimes Oregon white oak woodlands Frequent, low-intensity wildfires Background level of native insects and pathogens WA OR Oregon white oak woodlands Shrub-steppe Habitats Land use changes sage grouse

3 Land Use Changes 60% of WA shrub- steppe converted (Dobler et al. 1996) Invasive plant species: Impacts Compete with native plant species Alter ecosystem properties Disrupt wildlife-habitat relationships Hanford Reservation Yakima River Columbia Columbia River Dalmatian toadflax yellow starthistle (Centaurea solstitialis) diffuse knapweed Changes in temperature & precipitation Annual Average Temperature Hanford Meteorological Station (223.5m( m) Comparison of historical year-to to-year variations in temperature and precipitation with projected shifts in average temperature and precipitation (Casola( et al. [UW Climate Impacts Group] 2005) r = 0.35 P = Average (53.5 o F) Wildfire regimes: Effects of increasing temperature Increase in shrub-steppe steppe area burned, WA, OR, ID, (2X) (McKenzie et al. 2004) Longer periods of moisture stress. Longer windows for extreme fire weather (Rich et al. 2005)

4 Sage Sparrow Pre-fire ( ) 0.5 Post-fire ( ) 0 Mean (N=14) (t stat = 3.80, p = 0.002) Newsome et al Sagebrush obligate species decline (Newsome et al. 2004, Vander Haegen et al. 1999, Dobler 1994, Brandt & Rickard 1994) Biological soil crusts scarce and species-poor poor in areas of recent severe fire (McIntosh 2003) Shrub-steppe dependent wildlife Pygmy rabbit (Fitzner & Gray 1991) Sage grouse Small mammals (Gitzen et al. 2001, Brandt & Rickard 1994, Yensen et al. 1992) Invertebrates? (Welch 2005, Fielding & Brusven 1994) Switch from stand-maintaining to stand-destroying destroying fire regime Changes in species composition Shift in ecotone position Phenology of bunchgrasses advanced (27 days) Soil organic carbon reduced > 30% Total soil nitrogen reduced > 40% (Link et al. 2003, Smith et al. 2002) Sandberg s bluegrass (Poa( secunda) CO 2 Species big sagebrush Indian ricegrass Smith s wheatgrass Cheatgrass Implications Fuel loads + Fuel continuity = Fire frequency CO 2 (ppm) Biomass (g) * * Source Johnson & Lincoln 1990 Smith et al Smith et al Smith et al * P < 0.05 Cheatgrass Bromus tectorum Cheatgrass/wildfire cycle: Outcompetes native perennial seedlings frequency and extent of wildfires Replaces fire-sensitive perennial shrubs, grasses, and forbs. Conversion of shrub-steppe to annual grassland

5 Cheatgrass: : Impacts to ecosystem properties Native vascular plant diversity (Norton( et al. 2004, Whisenant 1990) Biological soil crust diversity (McIntosh( 2003, Belnap 2001) McIntosh 2003, Belnap & Phillips 2001, Soil physical properties (Norton( et al. 2004) Soil nutrient distribution & cycling (Norton( et al. 2004, R.D. Evans et al. 2001) Soil organic matter: Rate of cycling / amount (Norton et al. 2004, Knick & Rotenberry 1997) Soil faunal diversity (Kuske( et al. 2002, Belnap & Phillips 2001) Water use & community productivity ( Link et al. 1990, Cline et al. 1977) Anthropogenic Nitrogen (N) Fixation N fixation (Tg/yr) Total Anthropogenic Nitrogen Deposition ( from Fenn et al. 2003) Natural Sources Anthropogenic sources* (From Galloway et al. 2003) *Fertilizer production Legume crops Fossil fuel combustion Anthropogenic N: Ecosystem effects Alien annuals more effective at capturing soil N Richness, density, & biomass of aliens Richness, density, & biomass of native perennials (Schwinning et al. 2005, Allen 2004, Brooks 2003, Bashkin et al. 2003, Weiss 1999, Mclendon & Redente 1994, 1991, Wilson et al. 1966) Land use changes Anthropogenic N Deposition Deposition Plant community composition: Perennials Annuals Fire-adapted invasive species N 2 O Fire frequency Fire extent H 2 O stress Atmospheric CO 2 Fine fuels production Temperatures (Booth et al. 2003) Fuel loads + Fuel continuity = Fire frequency Ecosystem properties: Primary production Soil physical properties Nutrient cycling Associated organisms Human actions What do we do? Assessing the Vulnerability of Species, Communities, and Ecological Systems to Projected Climate Change in the Pacific Northwest Study Area Study Objectives Assess the impacts of future climate change on conservation targets in the Pacific Northwest Determine how projected changes may impact current protected areas and portfolio sites Develop analyses and products to facilitate smart conservation protection and management strategies TNC

6 Proposed products include Yellow-bellied Marmot Projected change maps Climate Vegetation Birds and mammals Portfolio-site specific analyses stable expansion contraction Figures, top to bottom: Flato et al., CGCM3.1 data; Shafer 2000; USGS.