BVLC STUDENT PROJECTS 2011
Student Project Summaries, Final Papers, and Data
Tree Height-Age Correlation within Varying Elevations
By Marissa Padgett, Norwood High School
The science of tree morphology and understanding the physiological characteristics of tree growth is constantly evolving. A correlation commonly pondered is that of tree height to tree age. This study attempts to understand the relationship between tree age and height and whether or not elevation plays a role in these morphological characteristics. By measuring three Engelmann Spruce trees in four different elevation zones (a total of twelved trees) in the San Juan Mountain Range of Southwestern Colorado, it was found that trees’ heights do differ in varying elevations but that is not the only reason some trees are taller than others. It was also discovered that different elevations present differences in the tree cores, such as: tree ring definition, core moisture, and how easy it was to core the trees. It was determined in this study that tree height has little relevance to tree age but elevation has a great impact on how a tree grows.
Effects of Elevation and Grazing on San Juan Mountain Plant Communities
By Sara Friedberg, Telluride Mountain School
This research predicts that the same species of plants growing on the Telluride Valley Floor will be much less abundant and behind in their growing pattern, than those of the same species higher up in Bridal Veil Basin due to fewer disturbances from animals and humans in Bridal Veil Basin, despite the higher elevation. The Telluride Valley, which is in the montane zone, is at an elevation of 8,750 feet and Bridal Veil Basin, in the subalpine zones is at 10,500 feet. The study took place in the Telluride Valley of the San Miguel River and Bridal Veil Basin, a prominent tributary valley perched above. The two different sites were chosen for this study to represent two different elevations and life zones. The location of study plots was decided according to where all three plants were found. At each of these sites, one plot was on a flat, sunny spot and the other was a flat spot with canopy cover. Plant counts, canopy cover, plant height, and soil moisture were collected and compared at each site. The plants on the Valley Floor are indeed shorter, and less abundant, presumably due to the grazing than the plants up in Bridal Veil Basin, even though Bridal Veil Basin is much higher in elevation and experiences harsher weather and a shorter growing season.
Forest Density and the Corresponding Effect on Tree Growth
By Jessie Hild, Telluride High School
The following study deals with growth rates of trees in a dense forest stand ascompared with a less dense forest stand. This study was within the subalpine life zone of Bridal Veil Basin in the San Juan Mountain Range of southwestern Colorado, more specifically the Lower Bridal Veil Basin just above the Bridal Veil Creek. The data consisted of the 18 cores from the tree specie Engelmann Spruce, the most prolific tree specie in the subalpine life zone of this particular area. This experiment hypothesized that trees located within asparse tree stand would grow more than trees located in a dense forest stand due to the lesser amount of competition amongst the trees within the sparse forest stand. 9 tree cores were taken from a dense tree forest stand and9 other tree cores were taken from a sparse tree forest stand within the same general area. 3 sizes of trees were sampled from within each forest stand. From the cores, the researche recorded the latest 10 year growth and average growth rate per year which the conclusions are based upon. After observing the collected data, it was concluded that the size of the forest stand, whether dense or sparse, did not significantly affect the growth of the trees within the plot.
The Relationship between Pika Populations and Vegetation Diversity
By Wyatt Murdy, Telluride High School
The hypothesis of this study is if Ochtonoa princeps or pika live in a area that supports more graminoids than forbs then their hay piles would contain more graminoids and pika would have a better rate of survival and their would be a larger population of pika in tha area. The study was conducted in the alpine zone of Colorado between 11500ft to 14000ft in elevation. The three different sites were at Blue Lake Cabin area, Colony one, Double Eagle Rock Glacier, Colony two, and Ophir Pass, Colony3. The study was conducted by observing pika at each of the three sites for two hours and taking 20-meter vegetation transect data every two meters, as well as analyzing the pika hay piles and foraging habits. The transect data and the pika observation resulted in a three percent difference of graminoids and forbs at Colony1, forbs being the higher percentage, and nine pika seen. Colony2 had the highest percentage of graminoids out of all three sites and the lowest percentage of forbs this site also had the lowest number of pika seen which was five pika seen. Colony3 had an 11 percent difference between forbs and graminoids with graminoids being the higher percentage, and six pika seen. The significance of the data is such that it could indicate that pika like to live in a area that supports an even distribution of both graminoids and forbs. Analysis of both old and fresh hay piles were examined. At colony1 the hay piles had a high content of old graminoids and fresh forb. Colony2 had an even pile of fresh forb and fresh graminoid and the highest percentage of old graminoid. Colony three had the highest percentage of old forb and the lowest percentage of old graminoid. This data could be showing is that the pika like to collect more forbs than graminoids at the beginning of the season, or since the old graminoid percentages were so high that could suggest that the pika don’t eat all of the grasses that they collect and they could be reusing the same bed of grass. The hypothesis states that if the area the pika are collecting from contains more graminoid than forb then there will be more pika in that area, and the data collected during this study seems to refute this hypothesis.
A Comparison of Aquatic Insect Sampling Tools
By Jean Denham, Nucla High School
A study was conducted to determine which aquatic insect sampling tool was the mostefficient in collecting the largest number of insects. The three tools used were the D-frame net, also referred to as a “kick net”, which is a net attached to a frame in a “D” shape; the kick screen, a very fine wire mesh; and the Surber Sampler, a bucket-like tool that has a hole in the front, bottom and back with a net attached to the back hole. All three tools were tested at two sites on Bridal Veil Creek, a healthy headwaters stream high in the San Juan Mountains of southwestern Colorado. It was hypothesized that the Surber Sampler would be the most precise in sampling the largest most accurate amount of insects, because it has a specific collection area for sampling. The kick screen tool, however, was the most the most successful sampling tool in this study.
American Dipper Population In Relation to Water Quality of Two Headwater Streams
By Keith Hill, Telluride High School
The following study was conducted to compare the population of American Dippers living in a healthy headwater stream, Bridal Veil Creek, and a contaminated creek, Howards Fork, in the mountains of Southwestern Colorado during August of 2011. This study predicts that with inferior water quality at the Howard’s Fork, there will be fewer American Dippers present, due to a lesser supply of aquatic macro-invertebrates because such aquatic insects are the Dipper’s food source. It also compares two headwater streams for their water quality, aquatic insect populations, and American Dipper populations. Through performing stream kicks, creating birding transects, conducting aquatic insect and Dipper counts, and using the Hannah Water Quality meter to test waters for pH, TDS, conductivity and temperature, Bridal Veil Creek produced seven total sightings of American Dippers during the twice performed .5 mile transect. In contrast, the Howards Fork, drowned in a significant amount of metals and dissolved solids, housed not one single macroinvertebrate. Its riverbed was devoid of all visible life, as were the three observation periods conducted alongside the stream. Adding onto other experiments testing the toxicity of the Howards Fork, this research now tells scientists, and the interested public, that bird life is also affected by the contaminated river which houses their food supply.
The Diversity of Aquatic Insects in Differing Detrital Environments
By Shelby Brier, Norwood High School
This study examines the relationship between the diversity of aquatic insects compared to the diversity of detritus at three different riparian locations. In August 2011 this experiment was conducted in Telluride, Colorado along the San Miguel River and Bear Creek (a tributary to the San Miguel). The hypothesis that greater aquatic insect diversity was a result of greater detritus diversity, and was tested by gathering samples of detritus and aquatic insects from each location. After the data was sampled and analyzed several conclusions were drawn. One key finding was that the diversity of detritus isn’t the only factor responsible for aquatic insect diversity. It was observed that the site with the second most diversity of detritus had the most diversity of aquatic insects. While the study isn’t able to determine what the specific factors responsible for aquatic insect diversity are, several conclusions were examined including nearby pollution sources.