WyomingView interns describe how satellite data can be used for monitoring past environmental changes

Emily Richardson (BS Botany) monitored aspen tree growth in normal, wet, and dry years along an elevation gradient in the Sierra Madre Mountains. She computed a vegetation index from Moderate Resolution Imaging Spectrometer (MODIS) data acquired in 3 years and analyzed tree growth based on their phenology curves. Aspen stands growing at lower elevations exhibited major changes during these three years, whereas their growth patterns at higher elevations did not show such variations.

Ryan Lermon (BS Rangeland Ecology & Watershed Management) mapped the burn severity at a prescribed fire site north of Rawlins, WY. Prescribed fires are part of forest management methods aimed at reducing fuel load, and improving overall habitat quality. Following a prescribed fire event, land management agencies are required to map how fire moved through the landscape but lack the necessary resources to generate it. Using a Landsat 8 image acquired after the fire, Ryan mapped the impact of this prescribed fire as high, medium, low and no-burn classes. This map will be used by agencies to establish field sampling plots for monitor vegetation regrowth.


Emily and Ryan presented their work in the Wyoming Undergraduate Research Day on 26 April 2014.

Following newspapers published a short description of Emily's work:

Laramie Boomerang - May 10, 2014 - Link to article

Casper Star Tribune - May 12, 2014 - Link to article

Washington Times - May 10, 2014 - Link to article

Eighth graders associate spectral reflectance patterns with plant form, health status

Eighth grade students at Laramie Junior High School learned to measure the spectral reflectance of leaves and analyze differences based on their types (conifers vs. deciduous) and health status (live vs. dying) during presentations by Ramesh Sivanpillai, principal investigator for WyomingView. The more than 75 students also learned how sensors in remote sensing satellites collect similar data about Earth surface features.

Students providing their feedback on remote sensing concepts and the hands-on activity that aimed at comparing spectral reflectance values of live vs. dead leaves from conifer and deciduous trees.

Ron Whitman, physical sciences teacher at the school, invited Sivanpillai to four sections of his eight grade classes to highlight remote sensing science and applications. “Ramesh introduced the electromagnetic spectrum with a very informative power point presentation during class period[s,]” he said. Whitman trained students to collect spectral data of the leaves, enter them in spreadsheet, and analyze them. This year’s activities spanned four class periods. “I was able to teach, on my own, the aspects of remote sensing, collection of data, displaying data and interpreting research data as initially taught by Ramesh,” he said.

Whitman noted the students continue to be excited about remote sensing and simple and complex tools. “Students compared their own data and other students’ data and discussed what was similar, different, and reasons for error,” he said. “Ramesh came back and helped students interpret their data and compare to other practical research by colleges and college students.”

WyView coordinator discuses phenology and leaf color changes in aspen trees

Student feedback highlighted different aspects of this lecture and hands-on exercise. Students are identified by initials for privacy purposes.

"I learned that the spectral reflectance values of things make a big difference in the world." KD

"I learned that the colors that you can see are based on what colors are reflected of of the object." KW

"I have learned that plant give off infrared radiation waves. They help us tell if the plant is healthy." DR

"I learned how to graph on the excel and I learned how to use a spectrometer" MH

"I also learned how satellites check out the environment from space from all around the world ... we learned how to plot and compare reflectance values." SH

"In the hands on activity I learned how to calculate the percent of reflectance of colors." CH

"I learned that live leaves reflect more than dead leaves." NT

"We also learned how to use Microsoft Excel and how it can graph scientific data." JW

"... a live leaf absorbs more of every other color but reflects green the most." SH

"I can definitely say that I learned new information about electromagnetic radiation and how it affects the colors that are visible for different species." KW

This event was conducted on March 31, April 1, 2, 8, 9 and May 19 as part of AmericaView’s Earth Observation Day activities aimed at introducing remote sensing science and applications to K-12 students and teachers.

Conner’s aspen phenology study wins third place in the 2014 Wyoming State Science Fair

Conner Whitman, an 8th grader in Laramie Junior High School, monitored leaf color changes in 3 aspen trees for 29 weeks (May – Oct 2013) by measuring their spectral reflectance values every week.

His research focused on how age and health status of these aspen clones influenced the changes in their leaf pigments. Every week starting in the spring, he collected leaves from 2 healthy (young and old), and 1 stressed (young) aspen trees and measured the amount of light reflected in eleven different wavelengths.

For comparison he also measured light reflected by an Engelmann spruce. Most conifer trees like Engelmann spruce do not exhibit prominent leaf color changes.

Using the amount of light reflected in infrared and red portions of the spectrum he calculated the different index which can be related to the amount of leaf chlorophyll content in each tree.

His results (figure above) indicated that the rate of chlorophyll change was influenced by health status of individual aspen trees within a clone. However there was no difference between the young and old healthy aspen trees. The light reflected by Engelmann spruce steadily increased throughout the year and did not show the declining trend in fall season.

Conner presented his research findings in the 2014 Wyoming State Science Fair in Laramie on 3/4/2014 and won the third place in the Plant Sciences category.

Laramie middle- and high-school students’ work showcased in 2012 AmericaView Fall Technical Meeting

Posters prepared by Laramie K-12 students on display in the main 
atrium of the USGS EROS Data Center, Sioux Falls, SD

Three K-12 students from Laramie had a busy summer measuring surface temperatures of natural and man-made features and the spectral reflectance values of leaves. These research activities were part of WyomingView's Earth Observation Day activities. Their findings were showcased in the 2012 AmericaView Fall Technical Meeting in Sioux Falls, SD.

Arundathi Nair, an 5^th grader in the Spring Creek Elementary School explored whether man-made surfaces (roads and concrete pavement) were hotter than a natural surface (grass lawn).  Her measurements taken at 10 am, 1 pm, and 6 pm revealed that temperature of all surfaces rose to their maximum values at 1 pm.  The temperature of the road was higher than that of concrete pavement.  Grass surface had the lowest temperature, which led her to conclude that man-made surfaces were hotter than natural surfaces.

Tire mulch mat installed in this park recorded an
average temperature of 65°C (150 °F) at noon, while the
average temperature of the grass lawn and concrete
pavement were 34°C and  25°C respectively

Sarah Arulsamy, an 8^th grader in the Laramie Junior High School was also interested in how different urban features absorbed radiation at different times of the day.  She measured the surface temperature of concrete sidewalks, grass lawns, asphalt roads and tire mulch in a park (right) at 8 am, 12 am, 4 pm, and 8 pm.  She measured each features at four locations (except tire mulch which was measured at only one location) in her neighborhood on five days.  Her research revealed that the temperature of roads and pavement were higher than grass lawns at any time of the day.  She noticed that the surface of the tire mulch in the playground recorded the highest temperature 65°C (150 °F) at noon.

Changes in the Normalized Difference Vegetation Index
values of aspen and cottonwood leaves sampled in Laramie, WY

Mrudhula Baskaran a 10^th grader at Laramie High School monitored spectral reflectance changes in aspen and cottonwood leaves.  Using an Alta II Reflectance Spectrometer she measured the spectral reflectance values of 10 leaves from each tree and computed the Normalized Difference Vegetation Index (NDVI).  She repeated these experiments on the 24^th August, and the 2^nd and 9^th of September, 2012.  While the NDVI values of aspen trees declined during this period, the cottonwood trees showed no change.  This study helped her to see the relationship between the changes in leaf color and reflectance.

Acknowledgements:
Thanks to Dr. Alan Buss, University of Wyoming, for loaning the infrared thermometer and Alta Spectroradiometer, and Dr. Kevin Czajkowski, University of Toledo, for providing the infrared thermometer used in these studies.