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Welcome to the NASA DEVELOP Hydrology team headquarters at Colorado State University
in Fort Collins, Colorado. The city of Fort Collins is located within the Cache la Poudre
Watershed, this semester's study site.
>>[Steve]: The Cache La Poudre watershed is located in the Front Range of Northern Colorado.
It's headwaters are located west of Fort Collins. The Poudre runs for 140 miles and drops a
total of 7,000 feet before it flows into the South Platte River. The watershed provides
habitat for wildlife and endless recreational activities such as hiking, rafting, fishing,
and hunting opportunities. Many people locally and regionally visit this watershed.
>>[Sky]: The watershed is also the location of the High Park Fire, which was first reported
on June 9, 2012. After the fire was finally contained, over 87,000 acres and 259 homes
were burned. Following the fire, torrential downpours ensued. Erosion of soil and ash
became a serious issue on the Poudre river, contaminating drinking water and choking fish
and other aquatic wildlife.
>>[Matt]: After the fire, the need for baseline data to monitor post-fire impacts on the Cache
la Poudre watershed became apparent, with the Colorado Water Resources Team spending
the spring term producing this important data.
>>[Amy]: The team goals during this term included: Developing a reproducible wetland modeling
methodology based on a thorough literature review
� Running a Boosted Regression Tree model to predict the presence or absence of wetlands
, Providing baseline data for the Poudre watershed, especially the post fire area for land managers
, And setting the stage for future remote sensing investigations by the future Fort
Collins Develop teams. >>[Steve]: Our work began with the acquisition and processing
of a number of Landsat 5 Thematic Mapper scenes taken during the wet months in the years closest
to the date of the fire. These were calibrated and had multiple indices such as NDVI and
NDMI derived using ENVI and ArcGIS 10 software. Soils data and a 30 meter digital elevation
model were also acquired, and slope and aspect layers were derived.
These remotely sensed data would serve as the predictor layers for our model.
We also downloaded spatial data from the US Fish and Wildlife Service's National Wetlands
Inventory. Random points were created within identified wetland areas to serve as our presence
points with which to train and test the model.
>>[Amy]: �All of our data was further processed and tested using the USGS's Software for Assisted
Habitat Modeling (or SAHM for short). This enabled us to remove highly correlated predictor
variables that would not aid in the modeling process.
This data was run through a Boosted Regression Tree model, which determined the statistical
relationships between our predictor variables and point data in order to predict presence
or absence locations of wetlands.
>>[Matt]: The model output reveals an array of wetland areas including permanently flooded
wetlands like reservoirs and ponds, as well as a large amount of riparian zones in the
headwaters region of the CLP watershed. Additionally the model predicted numerous wetlands within
the city of Fort Collins, which is likely due to water content in heavily irrigated
lawns and agricultural fields. >>[Sky]: This project has identified a method for modeling
wetlands in Northern Colorado, and has produced a preliminary map predicting wetland presence
in the Cache la Poudre watershed. The next steps for this project will be carried
out by the summer semester DEVELOP team and include field validation of our results, additional
comparative modeling, and dissemination of the combined results & methodology to the
public. So stay tuned and thanks for watching. [Accompanying music written and recorded by
Matt Luizza and Steve Chignell]