Western Mountain Initiative: Colorado

Research Project: 

RB00CMY.1

Project Manager: 

Jill Baron
A beautiful day at Loch Vale Lake, CO
A beautiful day at Loch Vale Lake, CO

Mountain ecosystems of the western U.S. provide irreplaceable goods and services such as water, wood, biodiversity, and recreational opportunities, but their potential responses to anticipated climatic changes are poorly understood. The overarching objective of the Western Mountain Initiative (WMI) is to understand and predict the responses, emphasizing sensitivities, thresholds, resistance, and resilience, of Western mountain ecosystems to climatic variability and change. Colorado State University participates with other institutions to address four key questions:

  1. How are climatic variability and change likely to affect disturbance regimes?
  2. How are changing climate and disturbance regimes likely to affect the composition, structure, and productivity of vegetation (particularly forests)?
  3. How will climatic variability and change affect hydrologic processes in the mountainous West?
  4. Which mountain resources and ecosystems are likely to be most sensitive to future climatic change, and what are possible management responses?

Specifically, the Natural Resource Ecology Laboratory will ask:

  • Where is the productivity of mountain ecosystems sensitive to climatic variability;
  • How do climatic variability, fire, and land use affect biophysical interactions in aquatic systems and soils; and
  • Which mountain resources and ecosystems are likely to be most sensitive to future climatic change, and what are possible management responses?

As mountain ice shrinks and the dynamics of seasonal snowpack change, an unexpected response appears to be altered water quality via increased heavy metal concentrations and nitrogen from newly-exposed sediments (Thies et al. 2007, Williams et al. 2007, Baron 2008, Baron et al. in review). This phenomenon has implications for high elevation aquatic ecosystems where slight increases in nutrients trigger eutrophication and where heavy metals pose a water quality risk. In the western U.S. there are many high elevation, ultra-oligotrophic water bodies as well as glacierized mineral belts with heavy metals (Fenn et al. 2003, Church et al. 2007). Based on water quality changes from melting rock glaciers in Colorado (Williams et al. 2007, Baron et al. in review), Canada (Lafrenire & Sharp 2005), and the Alps (Thies et al. 2007), we will explore this same phenomenon in Western mountains. Ecohydrology couples climate-caused changes in mountain hydrology with the responses of forest vegetation and disturbance (Breshears 2005). Changes in glaciers, snowpacks, streamflow, and water quality directly affect terrestrial and aquatic ecosystems, and changes in water relations in the coupled atmosphere-soil system affect vegetation through stress and altered disturbance regimes. Empirical studies will focus on semi-arid watersheds, in which vegetation responses are especially sensitive to drought and disturbances, and subalpine forests in Loch Vale (Central Rockies) where we build on existing long-term geochemical measurements. Modeling studies will use our existing set of case-study watersheds, addressing the full range of environmental gradients across the West.