Environmental Studies Independent Research and Study Papers
Environmental Studies and Science Majors engage in a variety of types of research. The projects listed here are 1 or 2 semester independent study or independent research projects that are conducted under the guidance of a faculty advisor and follow the department *guidelines* for research. To request access to a hard copy or pdf version of the papers associated with these projects, please contact the Environmental Studies Technician by emailing firstname.lastname@example.org. Independent Research Papers are also available through the Dickinson College Library.
Tiffany Chin, "Differing Seasonal Succession of Phytoplankton in Lakes with High and Low Dissolved Organic Carbon Concentrations: Implications for Long-Term Community Shifts"
In recent decades, rates of acidic deposition from sulfur and nitrogen emissions have been declining across North America (Stoddard et al. 1999). These declines, largely attributed to regional and national emissions regulations, have allowed for the recovery of aquatic ecosystems across the Northeast US and elsewhere. The effects of acid deposition on aquatic ecosystems are dependent on the rate at which deposition occurs and the acid neutralizing capacity (ANC) of each system (Driscoll et al. 2001). Acidic deposition has the greatest impact on perched seepage lakes, which are affected primarily by direct precipitation (Driscoll et al. 2001). High levels of acid deposition in past years have lead to decreases in pH and increases in aluminum concentrations in many ecosystems across the Northeast US, contributing to a decline in species richness and abundance (Driscoll et al. 2001).
In addition to the effects of changing rates of acidic deposition, recent climatic changes in this region are also impacting aquatic ecosystems. Annual temperatures have increased in the northeastern US by 0.08 ±0.01°C per decade over the past century, and this rate has increased to 0.70 ±0.05°C per decade over the past 45 years (Hayhoe et al. 2008). Annual precipitation has also increased over the last century by 9.5 ±2 mm per decade, and climate models predict that these precipitation increases will occur largely during the winter rather than other seasons (Hayhoe et al. 2008). These climatic changes have been observed in conjunction with reductions in the length of ice cover on lakes and changes to ratio of snow to total precipitation (Hayhoe et al. 2008). Such changes can impact the amount of snowmelt entering aquatic ecosystems as well as terrestrially derived dissolved organic carbon. Shifts in the length of ice cover on lakes may also affect the succession of species that are temperature-cued, as the timing of full mixing of the lake will shift.
Max Egener, "The Effects of Extreme Rain Events on Water Transparency and Stratification in Central Pennsylvania Reservoir Ecosystems"
Recent research suggests that the frequency of extreme rain events is increasing in the Mid-Atlantic region of the United States (84% increase since 1948 in this study region). Three reservoirs in central Pennsylvania with varying catchment land use and morphology were monitored over the open water period to measure the effects of extreme rain events (>2.54 cm in 24 hours) on reservoir water transparency, stratification, transparency relevant chemistry (total suspended solids, chlorophyll-a, and dissolved organic carbon), and nutrient chemistry. Reservoir maximum depths were 3.5 m, 7.0 m, and 16.0 m. The catchment land use of Laurel Lake and Fuller Lake is 92% forested, and the catchment land use of Opossum Lake is 44% agricultural and 40% forested. Measurements were collected from Laurel Lake and Opossum Lake on ten days from mid-May to November, as well as within twenty-four hours before and within forty-eight hours after a spring and a fall extreme rain event. High frequency temperature and oxygen sensors were deployed at varying intervals throughout the water columns of all three reservoirs to monitor changes in thermal stratification at the event-scale. Reservoirs with different catchment characteristics experienced dissimilar alterations in water transparency following the spring and fall extreme rain event. Changes in transparency relevant chemistry reflected changes in water transparency. Nutrient chemistry following both extreme rain events suggested that light availability is the primary driver of primary production in Laurel Lake and Opossum Lake. A weakening of stratification occurred more frequently following extreme rain events in reservoirs with shallower maximum depths. These differing responses to extreme rain events in each reservoir warrant reservoir-specific management programs to address ecological changes in response to this local effect of climate change. Further research should seek to understand the long-term effects of these short-term changes on reservoir ecology.
Rachael Sclafani, "Garlic Mustard: Impacts on Understory Diversity and Competitive Interactions"
Garlic mustard is a Western European plant invasive in the United States. It has a number of traits that allow it to be highly invasive in the forest understory such as allelopathy, tolerance of low-light conditions, and phenology that allows it to outcompete other species early in the growing season. On a community level it has been found that Garlic Mustard causes decreases in diversity in the forest understory, however in greenhouse experiments it has been seen that the competitive advantage of Garlic Mustard varies. This study is intended to determine how Garlic Mustard impacts understory diversity at different densities using an observational field study and how it interacts competitively against Japanese Stilt Grass and Japanese Honeysuckle in a greenhouse competition study. In the field 30 1m2 quadrats were sampled recording abundance and percent cover. The greenhouse experiment was set up to vary the density and proportion of each species. In the field study Japanese Stilt Grass showed a negative relationship with Garlic Mustard, however it was not negatively impacted by Garlic Mustard in the greenhouse study. Japanese Stilt Grass seemed to be able to negatively impact the growth of Garlic Mustard. This incongruity is potentially due to an allelopathic effect of Japanese Stilt Grass on Garlic Mustard in the dense conditions of the greenhouse that was not a large factor in the less-dense field. Japanese Honeysuckle showed a positive relationship with Garlic Mustard in the field, but a strong negative relationship with Garlic Mustard in the greenhouse. The incongruity might have been due to the ability of Garlic Mustard to shade out the Japanese Honeysuckle in the greenhouse, whereas in the field the Japanese Honeysuckle can be rooted away from the Garlic Mustard, avoiding this impact.
Tabea K. Zimmermann, "Reconstructing the Effects of Multiple Stressors on Algal Communities in Lakes with Differing Concentrations of Dissolved Organic Carbon"
Inland waters are particularly sensitive to environmental changes and a growing body of research points to lakes as sentinels, integrators and regulators of large-scale stressors such as climate change (Carpenter et al. 2007, Pham et al. 2008, Williamson et al. 2008, Adrian et al. 2009). As low points in the landscape, inland waters receive and process inputs from the surrounding terrestrial environment and atmosphere and respond quickly to changes in precipitation, wind and solar irradiance (Williamson et al. 2009). The reactions of these sensitive ecosystems to landscape and climatic changes are stored in lake sediments, which serve as archives to aquatic and terrestrial-ecosystem response to changing conditions in the past (Williamson et al. 2009).
Alexandra Raczka, "Privilege and the Food Environment in Carlisle, Pennsylvania"
This study looks at the food environment of Carlisle, Pennsylvania. It is specifically focused on food access and food preferences, and the relationships between a person’s educational background, household income and geographic location and what they choose to eat based on what they have access to.
Anna E. McGinn, "Quantifying and Understanding Ecological Literacy, A study of first-year students and liberal arts institutions"
Ecological literacy measures a person’s knowledge of ecological systems, care for their immediate and global environment and level of action to reduce his or her personal and communal impact on the environment. This study investigates the level of ecological literacy of first-year students who entered seven liberal arts colleges in Pennsylvania in the fall of 2013. The institutions included in the study are Allegheny College, Bryn Mawr College, Bucknell University, Dickinson College, Gettysburg College, Haverford College and Swarthmore College. 426 students were surveyed during their first three months of college, and the data was processed to quantify the number of students who are ecologically literate and to examine the potential triggers for and pathways toward ecological literacy. The study shows that 58 percent of students have some level of ecological literacy while the remaining students are ecologically illiterate. In addition to questions that tested for ecological literacy, the survey collected demographic information and gauged a student’s level of exposure to nature. This study does not find that these factors are predictors of a person’s level of ecological literacy. Between the three sections of ecological literacy, a student’s level of care does correlate with a student’s level of action, but neither action nor caring correlate with knowledge. The aim of this research is to support schools in better catering their sustainability efforts towards students with low levels of ecological literacy, so all students who reach the undergraduate level of education will leave the educational system with a basic understanding of the major environmental issues facing today’s world, a feeling of responsibility to address these challenges and the competencies to contribute positively toward building a more sustainable society.