Physical Sciences and Mathematics Commons^™

The Quantitative Assessment Of Pond Scum: An Examination Of The Biogeochemistry Of Phosphorus Cycling In The Belgrade Lakes, Abbey M. Sykes

Honors Theses

The internal recycling phosphorus in freshwater lake bottom sediments represents a significant source of hypolimnetic phosphorus (P) release for many of Maine’s lakes. In summer months, Maine lakes often thermally stratify and the lake hypolimnion develops anoxia, leading to a reduction in redox potential at the sediment-water interface. These reducing conditions facilitate the reductive dissolution of ferric iron, and, since phosphorus is often present in freshwater lake sediments as solid FeOOH-PO₄ complexes, results in release of soluble phosphorus into the water column. Our current study presents field and laboratory data from sediment fractionation extractions designed to quantify concentrations of …

Measuring Differential Forest Growth In The Sheepscot River Headwaters With Bitemporal Lidar, Soren Denlinger

Honors Theses

In recent years, lidar has proven itself as a forestry tool capable of accurate, large- scale inventories. Lidar has even shown utility in multitemporal analysis and growth assessment, given high-resolution or small-scale point clouds. However, lidar’s efficacy as a multitemporal tool with relatively low-resolution, large-scale datasets is comparatively unknown. In this study, I compared forest in Midcoast Maine bitemporally, with publicly available datasets from the years 2007 and 2012. Specifically, I compared differences in growth characteristics of riparian, wetland, and upland forests. Although the 2007 dataset (created for geomorphological research) and the 2012 dataset (statewide, general-purpose) possess varying point densities …

Projecting Regions Of North Atlantic Right Whale, Eubalaena Glacialis, Habitat Suitability In The Gulf Of Maine In 2050, Camille Ross

Honors Theses

North Atlantic right whales (Eubalaena glacialis) are endangered. Understanding the role environmental conditions play in habitat suitability is key to determining the regions in need of protection for conservation of the species, particularly as climate change shifts suitable habitat. This thesis uses three species distribution modeling algorithms, together with historical data on whale abundance(1993 to 2009) and environmental covariates to build monthly ensemble models of past E. glacialis habitat suitability in the Gulf of Maine. Then, the models are projected onto the year 2050 for a range of climate scenarios. Specifically, the distribution of the species was modeled …

Developing A Predictive And Dynamic Moose-Vehicle Collisions Model In Maine, Yue Yu

Honors Theses

Wildlife-vehicle collisions are a major form of human-wildlife conflict. Predictive animal-vehicle collision models have been developed to identify collision hotspots in Maine and guide mitigation strategies. However, most current models are static and unable to produce dynamic forecasts that incorporate changing climate and weather. The goal of my study was to develop a predictive and dynamic model of animal-vehicle collisions in Maine, USA. More than 6,700 moose-vehicle collisions (MVC) occurred from 2003 to 2017 in Maine, raising road safety, socio-economic, and wildlife conservation concerns. I sought to identify factors that contribute to a higher probability of MVCs by comparing two …

America's National Parks And The Anthropocene: Addressing The Present To Accommodate The Future In Acadia National Park, Sophie A. Swetz

Honors Theses

In 2000, atmospheric chemist, Paul J. Crutzen, and limnologist, Eugene Stoermer, formally proposed the idea of “the Anthropocene,” a new geologic epoch in which humans are the dominant force shaping the Earth. To claim the Anthropocene's existence is to declare that human actions have altered the Earth in such a way that geologic indicators render it a distinct epoch in the stratification of geologic time. This new epoch emerges as a consequence of increased technological development employed to accommodate an anthropocentric human existence. That is, rapid advancements in technology have driven the transformation from a primarily naturally controlled planet to …

Missing The Trees For The Forest: The Socioecological Significance Of Dispersed Farmland Trees In Northern Ethiopia, Jacob A. Wall

Honors Theses

Scattered trees are prominent features in the agricultural landscape of the Ethiopian highlands. The dry Afromontane forests of the Amhara Region in northern Ethiopia have faced centuries of deforestation - the FAO estimates only 3% of the region is forested today. The remaining landscape has been largely converted into agricultural and grazing lands, with the exception of some limited government-protected lands, as well as thousands of small forest fragments left around Orthodox Churches (“church forests”). But while a growing body of scholarship has highlighted the ecological and cultural importance of church forests and other natural forest fragments, the roles of …

The Roles Of Introduced Eucalyptus In The Conservation And Expansion Of Ethiopian Orthodox Church Forests In The Northern Ethiopian Highlands, Janice Liang

Honors Theses

Species of the genus Eucalyptus (common name eucalyptus) are widely planted all across Ethiopia – including on large areas of land previously allocated to food production. In recent decades eucalyptus has also increasingly been planted on lands around and within “church forests,” sacred groves of old-aged Afromontane trees surrounding Ethiopian Orthodox Tewahido churches. These revered holy sites have long been recognized for their cultural values and also for their ecosystem services – including their potential to support species conservation and restoration, as church forests are some of the only remaining sanctuaries for many of Ethiopia’s indigenous and endemic plant and …

Assessing The Carbon Impacts Of Colby College’S Biomass Plant, Alice Hotopp

Honors Theses

Biomass energy plants are considered to be carbon neutral systems under some definitions. However, this concept of carbon neutrality needs to be rethought in order to understand the true carbon impact of biomass plants upon global climate change. A biomass plant’s wood source, the extent to which the biomass plant emits carbon dioxide, and the timescale over which the biomass plant emits carbon should all be taken into account. In this study, I consider the Colby College biomass plant’s role in carbon cycling. Colby’s Physical Plant Department provided me with information on how much carbon (tons of woodchips) is used …

Cameras, Satellites, And Surveys: A Multi-Platform Approach To Monitoring Lake Conservation Behavior, Daniel D. Homeier

Honors Theses

Shoreline buffers are essential to maintaining lake water quality and there are numerous methods for their assessment. There is uncertainty in the benefits and drawbacks of different shoreline buffer assessment methods. In this study I explore three methods of remotely assessing shoreline buffers in the Belgrade Lakes Region of Maine: household surveys, geotagged shoreline photos, and satellite imagery. By comparing these three methods I will evaluate their accuracy and applicable scale when used to assess the presence and quality of shoreline buffers.

I used both parametric and non-parametric analysis to (1) evaluate the relative accuracy of 154 household surveys in …

Learning The Lay Of Their Land: Data Recording By Maine Land Trusts, Patrick John Roche

Honors Theses

Land trusts have led the recent, rapid expansion in private land conservation in the US. As they have grown, many questions have emerged as to the value of their conservation efforts, especially in the long-term. To address this data gap, studies have evaluated easement restrictions and the characteristics of land trust protected property. I take a novel approach by investigating the data that land trusts record about their protected properties and its impact on their capacity to protect conservation values. I surveyed 55 land trusts operating in Maine about data they record in baseline documentation reports. A majority (82%) had …

Factors Influencing Conservation Success Or Failure In Tiger Range States, Megan C. Saunders

Honors Theses

Tigers are currently found in 13 countries. Three of eight recognized subspecies are extinct and the other subspecies are considered endangered throughout their range. Major threats to tigers include habitat and prey loss and poaching. Most studies of tiger decline, to date, have explored direct threats. This study uses a range-wide approach to explore possible underlying drivers of tiger decline. I used recent tiger population estimates and identified 6 biological measures and 27 socioeconomic measures to ask why some countries are more successful in conserving tigers than others. Data were analyzed using correlation and regression analyses in SPSS. Higher rates …