Science Spotlight

Station P048

Researcher: Bill Smith
University of Montana

P048 is located west of Bozeman, Montana.

State: MT
Country: United States
Elevation: 1492.6 m
Lat/Long:  45.653 / -111.2042

Vegetation Studies in Montana

Plant growth is a measure of the total CO2 removed from the atmosphere and stored as plant biomass. Being able to measure plant growth and also predict future changes is essential for our understanding of climate change, given the critical role plants play in the global carbon and water cycle.

The goal of this research is to use reflected GPS signals to estimate plant growth. We compare the measurements from the GPS receivers with real-world field measurements of plant growth and then also with satellite estimates of vegetation growth. This helps us validate that our satellite methods work correctly. Once we confirm the accuracy of our satellite methods, we can then estimate the total amount of plant growth for the entire planet, which we do in my lab at the University of Montana.

Figure 1. "Ground truth" data are needed to validate the GPS method for estimating vegetation growth.

Figure 3. At CU the vegetation was weighed, dried, and re-weighed. These data provide the wet weight, dry weight, and water weight data shown in this figure.

Figure 5. The station looks barren after the growing season is over.


Figure 2. Bill visited four PBO sites every two weeks. At each visit he measured the height of vegetation and shipped the clipped vegetation to the lab at the University of Colorado.

Figure 4. Bill's measurements have since been compared with the GPS measurements of plant growth that are defined by the acronym NMRI. There is a strong correlation between them, indicating that NMRI is measuring water content. Here the colors are defined as in the map in Figure 2.

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Last modified: 2019-12-26  16:24:53  America/Denver  


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