Quantifying the resilience of Rocky Mountain Forests to climate variability

Timeframe: 
2013

Understanding and measuring forest responses to climate change and land use practices is of paramount importance across the Western U.S.  More importantly, we need to understand the consequences of climate change on these ecosystems so that we can educate and implement policy to mitigate the negative effects.  In the Western U.S., forest productivity is largely controlled by water; therefore, understanding the biophysical controls of water availability is vital for maximizing forest productivity while minimizing the use of water resources.  Our main objective is to explore how landscape structure mediates the spatial patterns of water delivery, storage, and availability, and the resulting tree responses to these spatial and temporal patterns of water availability.  We will combine concurrent measurements of hydrometric, physiological, and geospatial variables across a watershed with different topographic features to address our objectives.  Our study will focus on understanding the mechanisms and processes that control water movement across a watershed so that we can apply our approach to other watersheds across the Western U.S. 

Update March 2015:

Climate change is impacting forests through increases in drought frequency, duration, and severity, leading to potential decreases if forest productivity.  However, we currently lack an understanding of how productivity is influenced by climatic, topographic, and physiological relationships.  In our study, we link physical watershed characteristics with plant physiological responses to gain a comprehensive view of how changes in precipitation influence forest productivity.  We addressed three main objectives in our study last year.  First, we examined how landscape topography and organization influence tree productivity.  We cored approximately 800 cores throughout our experimental forest in Western Montana to examine how topographic position (elevation, aspect, hollow/hillslope) affects basal area growth (Jencso).  We also installed real time dendrometers bands to measure changes in intra-annual growth (Hu).  Second, we assessed how different proportion (rain versus snow), magnitude and timing of precipitation influenced tree growth across topographic and elevational gradients.  We collected xylem, soil, and water samples throughout the watershed and used stable isotope analysis to track how different tree species used water sources throughout the year (Hu).  We also installed sap flux sensors into 32 trees in different landscape positions to examine water use differences among three species (Hu).  Finally, we developed ‘wireless’ environmental sensors using Arduino dataloggers, which will allow us to measure air temperature, relative humidity, soil moisture and conductivity, changes in basal area increment and transpiration rates throughout the watershed (Jencso).

Partners

MSU IoE Office

Montana State University
605 Leon Johnson Hall
Bozeman, MT 59717
(406) 994-2374
MSU Director: Cathy Whitlock

UM IoE Office

The Universityi of Montana

The University of Montana
Davidson Honors College
Missoula, MT 59812
(406) 243-6058
UM Director: Maury Valett

 

Montana University System

Montana University System

Office of the Commissioner of Higher Education
2500 Broadway Street
Helena, MT 59620
406-444-6570