Climate variability, land use, disturbance regimes, and water supplies in a Rocky Mountain ecosystem
Poster Number:
357
Presenter/Primary Author:
Patrick Bourgeron Our study areas include portions of the Niwot Ridge Long Term Ecological Research site and Boulder Creek, which is representative of the Colorado Front Range, where population increased by 30% from 1990-2000, reaching 3.5 million. Population growth continued to exceed the national rate from 2000 to 2005. The primary goal of this study is to characterize how human systems interact with three key structural drivers in Colorado:
- Climate
- Hydrology (streamflow)
- Landscape patterns of disturbances (fire and mountain pine beetle, MPB)
Three questions guide our analysis of long term climate, hydrology, and land use data:
- How do disturbances interact with each other to alter ecosystem structure and function (e.g., hydrological budget)
- How do altered ecosystem dynamics affect critical ecosystem services (including water quantity and quality)
- Which regional and global human actions and decisions concerning landscape management influence the disturbance regimes and their interactions further affecting ecosystem services
Preliminary results indicate that climate variability, population increase, changing land use, and fire suppression are likely to combine to induce shifts in structure and function at all elevations and spatial scales. Extreme droughts combined with fuel loading increase (due to fire suppression) and land-cover change (a function of land-use change, such as exurban development) may alter landscape patterns, stand structure, and hydrological budgets. However, the relationship between precipitation and streamflow exhibits different patterns within and among elevation zones.
Furthermore, changes in landscape patterns and stand structure in turn create a positive feedback to fuel loading accumulation and tree stress, and therefore likely influence the threshold behavior of fire and MPB outbreak intensity and size. Such changes in landscape patterns profoundly impact hydrological budgets and associated ecosystem services.
