Poster Session

High School Poster Winners

First Place: Sofie Rueter, Bangor High School
Aquatic Oxygenation: Unraveling the Vital Connection Between Phytoplankton and Dissolved Oxygen

Honorable Mention: McKenzie Vorenkamp, Bangor High School
Analyzing the Correlation of Human Activity to Microplastic Concentration along the Arctic Brook Stream using Arc-GIS and Image Analysis

Undergraduate Poster Winners

First Place: Sadie Gray, University of Maine Farmington
Zooplankton Sensitivity to Climate-Driven Conditions in High-Elevation Lakes in Maine

Honorable Mention: Samantha Summerfield, St. Joseph’s College  The Carbon Cycle in Hydroponic Farming

Graduate Poster Winners

First Place: Cade King, University of Maine
Analyzing Measured Flows for Salmon Habitat Management in the Upper Penobscot River

Honorable Mention: Paulina Alulema-Pullupaxi
Physicochemical Factors Influencing Release of Per- and Polyfluoroalkyl Substances from Spent Granular Activated Carbon in Landfill Environments

High School




High School

1. An Investigation into the Filtration Effectiveness of Vegetable Oil Against Nonpolar Liquid Contaminants in Water

Alexander Busko (student)
Bangor High School

Organic pesticides are leeching directly and indirectly into natural waterways, having detrimental impacts on aquatic ecosystems. Current filtration techniques to remedy these contaminants are suboptimal, highlighting the importance of developing novel methods. This project examined a vegetable-oil based filtration technique to remove nonpolar liquid contamination from water. As like molecules attract, nonpolar vegetable oil is a candidate substance to remove nonpolar contamination from polar water. To test this, an innocuous nonpolar solvent dye, maintaining similar properties to detrimental pesticides, was agitated into water. This contaminated water sample was poured through a vegetable oil layer, facilitating an interaction between the solvent dye and vegetable oil which enabled separation of the solvent dye from the sinking water. The filtered water that collected below the vegetable oil was drained through the bottom of the filter column. Pre and post filtration water samples were processed through a spectrophotometer to determine change in absorbance, which was used to determine a removal efficiency of the solvent dye from the water with vegetable oil. The proposed system was quantified to remove ~100% of solvent dye in all trials conducted. This suggests the proposed system could be effective at removing nonpolar liquid contamination from water (such as pesticides). Furthermore, the system is completely passive; this simplicity encourages the sustainability of using this technique for real-world application. To enhance this research, further filtration testing with actual contaminants will be conducted. Positive filtration results would encourage the idea of real-life application to address nonpolar liquid contamination in water.

2. Utilizing Additive Manufacturing to Develop a Sonar-Enabled Depth Sensor on an RC Boat

Raphia Mattsen (student), Brandon Brozman (student)
Bangor High School

The first 3D-printed boat that will be capable of determining the depths of the water in a sufficient, eco-friendly, affordable, and accessible way has recently been designed and printed. Boat parts were chosen for the design because they were inexpensive and provided the form and function needed for the boat. The current way to measure the depth of water is to take a full-size boat to the water, manually drive it out to the location, and then drive the boat back. This takes time, causes pollution, and costs more money than it is worth. Our boat is toy-sized, runs on battery power, is operated by remote control, and is eco-friendly. The reason for choosing our sonar sensor was because of its quick readings of the depth and how it relays the data straight to a smartphone which then makes a diagram of the water depth. The boat and sonar sensor have been tested in a small tub with success in both maneuverability and data collection. Further testing will be required to validate its use on a real surface water body. This method of depth-finding has applications in the real world because of droughts, floods, and ever-changing depths of water.

3. Monitoring the Impact of Hurricane Lee on Taunton Bay

Isaac Poliquin (student)
Bangor High School

In recent years, hurricanes have been landing more frequently on the Maine coastline, an event which was uncommon in the past. It is vital to figure out a means of which to monitor the health of the coastline in the face of these hurricanes to ensure these new events do not dramatically affect the coastal ecosystem and by extension the local wildlife and economy. In order to accomplish this, water samples were taken from Gordon’s Wharf, a location on Taunton Bay, directly before and after Hurricane Lee arrived. Strong differences in the pre and post storm samples were expected to showcase the effect of the storm on the bay. These samples have been tested for conductivity, pH, and total alkalinity. The results of the data indicated no significant changes before and after the hurricane. This result likely indicates that other factors are at play during hurricanes that may increase conductivity and alkalinity, such as salt-rich ocean water being brought into the bay. This would result in the changes brought about from increased freshwater from the storm being canceled out, producing similar readings before and after the storm hit the bay. This indicates that individual hurricanes do not drastically change the chemistry in the bay itself. Further research should be done on different locations around Taunton Bay or around other bays along the Maine coastline before and after a hurricane to measure the impact that the overall area has been experiencing due to the increased number of hurricanes.

4. Aquatic Oxygenation: Unraveling the Vital Connection Between Phytoplankton and Dissolved Oxygen

Sofie Rueter standing by her winning poster
Sofie Rueter, Winner of the High School Poster Award

Sofie Rueter (student)
Bangor High School

Producing over fifty percent of Earth’s oxygen, phytoplankton are essential to maintaining a natural equilibrium of oxygen and carbon dioxide in our atmosphere. However, there is a fine balance of factors that must be maintained within an environment in order to ensure stability within an algal population. There are many known environmental factors that contribute to algal blooms; scientists are still investigating how these factors work together to create an algal bloom. While much research has been conducted on the behavior of phytoplankton, there is surprisingly little data on the effects of aeration on phytoplankton. Through monitoring the growth and dissolved oxygen levels in the species of phytoplankton known as Nannochloropsis oculata, a species of phytoplankton found in all of Earth’s bodies of water, it has been demonstrated that the aeration of water causes stable algal populations, while stagnant water creates an environment that fosters algal blooms, thereby confirming the impact of an environmental factor on a critical component of all marine ecosystems. Future work could include conducting this experiment in a larger body of water in an attempt to better model the effects of aeration not only on algae but also on algae as they exist within a functioning ecosystem. Continuing to research factors that could cause algal blooms will slowly become more and more important as the human population grows and climate change continues to heat up our planet, fostering ideal habitats for increasingly harmful, increasingly out-of-control algal blooms.

5. Lowering pH Levels in Large Bodies of Water

Daniel Tarr (student)
Bangor High School

As we all know there are many effects from climate change. The one problem I’m focusing on is the effect that climate change has on our oceans. Climate change has impacted our oceans by increasing acidity levels. Ocean Acidity happens when there is an abundance of CO2 dissolving into the oceans. Ocean acidification must be addressed because, by having a high ocean acidification level crustaceans and coral reefs are unable to thrive. In addition, without the crustaceans many states like Maine are unable to have a stable economy, because they rely on many aquatic animals. For my project, what I did was create a caging for a pump by using reusable plastic filament. So what I am trying to do is to take shredded plastics and then put them into a filament extruder. The reason why I did this is to solve another problem for our oceans and that is the amount of plastics that end up in the ocean. This takes those plastics, and puts them into a more useful purpose. And then put that filter in the caging. The results that I expect is to see a lowering of the pH in the water that I have put my filter in. However, I expect to see a little bit of trouble when implementing the filter into the ocean. My future research is going to be implementing a reverse osmosis system into my filtering process to see if that is a more efficient way.

6. Analyzing the Correlation of Human Activity to Microplastic Concentration Along the Arctic Brook Stream Using Arc-GIS and Image Analysis

McKenzie Vorenkamp (student)
Bangor High School

Microplastic pollution is an extensive environmental issue resulting from the pervasive consumption of single use plastic found in health products, food containers, polyester goods, and more. Microplastics are easily distributed into the environment and unidentifiable due to their incredibly small size. Yet, the use of image analysis and arc-GIS mapping makes it possible to identify microplastics and the locations of distribution in areas; more specifically in local water sources. The research goal of this study was to conduct an analysis on the Arctic Brook stream in Bangor, Maine to identify microplastic concentrations in relation to surrounding human activity. Ten sediment samples were extracted and carried through a series of methods that circumscribed the microplastics. Image analysis was used in order to calculate the microplastic concentrations for each site. Arc-GIS was used to create a visual analysis of the concentrations and their placements along the Arctic Brook, as well as human influence. The results of the research include ten sites with concentrations ranging from 18.6 to 2.4 parts per gram; as well as a map analysis of the sites that was layered with a selective zoning map of different land uses from human activity. The usage of these methods can be expanded to multiple water systems within one town along with expansion of the visual to conduct further analysis. The identification of microplastics within a specific area through the use of these methods can bring awareness of the town area’s ability to distribute microplastics in local water sources.

Undergraduate Posters

7. Mitigating Maine’s Algae Blooms: New Insights from North Pond Sediment Analysis

Raegan T. Calvert (1) (student), D. Whitney King (1), Danielle J. Wain (2), Casey O’Connor (1)

  1. Colby College
  2. 7 Lakes Alliance

The reductive dissolution of solid FeOOH-PO4 complexes from lake bottom sediments introduces a significant source of phosphate into the water column, feeding summer algal blooms throughout many of Maine’s lakes. The 2018 alum addition to East Pond in Smithfield, ME proved successful in suppressing algae blooms by reducing internal phosphate loads, and we hope to utilize the same method in combating nearby North Pond’s annual algae bloom. To support a future treatment, we collected sediment samples from North Pond and conducted “jar tests” to determine the amount of alum needed to sequester 80% of phosphate. Samples were collected from a variety of lake depths (2.4-5.5m) and sediment depths (0-10cm). Sediments underwent four chemical extractions to address the following: (1) determine dose response of alum on phosphorous sequestration, (2) identify fraction of aluminum recovered after sodium hydroxide treatments, and (3) determine abundance of iron in sediment. We applied Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) to quantify the abundance of aluminum, iron, and phosphorous and thermogravimetric analysis (TGA) to determine the percent organic carbon in sediment. Our results reveal an incomplete recovery in the aluminum added to the sediment compared to the aluminum recovered after extraction. These findings suggest a competition between organic carbon and phosphorous for aluminum. The data presented informs an improved model of aluminum dosing which incorporates the competition between organic carbon, Fe (III), Al (III), and PO43- to predict sediment release of phosphate under seasonally anoxic conditions.

8. Ensuring Representation of Diverse Perspectives in Maine’s Climate Plan

Louise Chaplin (student), Catherine Mardosa (student), Sharon Klein, Caroline Noblet
Mitchell Center for Sustainability Solutions, University of Maine

Our project, led by the University of Maine Mitchell Center for Sustainability Solutions (MCSS), aims to increase participation and inclusion of Maine’s disadvantaged populations in the next statewide climate plan. The Maine Climate Council and its six Working Groups are currently developing the new state climate plan, which will be released in December 2024. This is the second iteration of the 2020 “Maine Won’t Wait: A Four Year Plan for Climate Action”. The 2020 plan established the Equity Subcommittee; a group of researchers, community representatives, and professionals. The Equity Subcommittee submitted an official report in March 2023 outlining recommendations to the Maine Climate Council, with the goal of increasing participation of at-risk communities such as Indigenous people, people of color, low-income households, and rural communities. This research project, funded by the Governor’s Office for Policy, Innovation, and the Future, is using the Equity Subcommittee’s recommendations to guide outreach in communities across the state. To better base our work in community-led processes and values, we are working with organizations local to our target communities, such as the Community Organizing Alliance and A Climate to Thrive. These partner organizations will help facilitate discussions, surveys, and focus groups in our 20 target communities, in collaboration with the MCSS team. Our work will culminate in a series of recommendations to the Working Groups, based on feedback we receive in our outreach efforts.

9. Regional Climate Signals in Maine

Caitlyn Daigle (student), Alexander Debo (student), Lucky Mourredes (student), Jason Moore (student), Cara Perry (student), Eme Saverese (student), Kennedy Todd (student), Sophia Winters (student)
Division of Natural Sciences, University of Maine Farmington

Maine’s geography spans gradients of elevation, latitude, and coastal proximity, resulting in multiple climatic zones throughout the state. Watersheds in different regions of the state reflect these varied climate conditions, particularly in response to precipitation, snowpack, and ice duration. Additionally, different regions of the state, and their watersheds, may exhibit differing trends in climate change signals over time. In this study, our team investigated trends in precipitation, snowpack, river ice, and river flow in four different regions of Maine, (north, central, west, and south) with a focus winter as a season with identified rapid change in New England. We utilized the Maine Geological Survey (MGS), the Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS), and the United States Geological Survey (USGS) National Water Information System to collect datasets spanning from 10+ years (precipitation) to 35+ years (river flow). We used quantile regression to identify trends over time for precipitation, snowpack, and river flow in each of the four regions. Direction and magnitude of trends varied by parameter, geographic region, and dataset quantile, and strongest trends were observed in the north and south regions of the state. These results illustrate spatial heterogeneity in climate conditions and trends, emphasizing the need for comprehensive data collection across regions.

10. Forecasting Maine Lake Health: Integrating Interdisciplinary Data for Secchi Depth Prediction

Adrian Gellert (student), D. Whitney King 
Colby College

This interdisciplinary research project aims to forecast future Secchi disk depths in Maine lakes by integrating past field-collected lake data, weather metrics, and physical limnology parameters. The study leverages observational and water chemistry data, including Secchi disk observations, dissolved oxygen profiles, and phosphorus grabs, from over 1,000 Maine lakes collected since the 1950s by scientists and volunteers. It also incorporates weather metrics and physical limnological parameters in an effort to create a forecasting model for all 6,044 lakes in Maine. Preliminary findings reveal challenges in integrating raw data on water chemistry, morphological data, and Secchi disk observations, prompting the calculation of parameters such as the Schmidt Index as a dimension-reducing solution. The Schmidt Index data allows us to omit the raw morphological data because it is based on the shape of the lake and captures that information. Previous research on this topic indicates that various factors are significant in predicting Secchi depth, including temperature, dissolved oxygen, chlorophyll, and phosphorus content. However, we have found that meteorological data is necessary to refine the model for predicting Secchi depth on a weekly and monthly basis. This project will offer valuable insights for policymakers and community members to prioritize management strategies and preserve lake ecosystems. Additionally, it will serve as a warning system for algal blooms.

11. Communicating the Economic Benefits of Maine Lakes in the 21st Century

Melissa Genoter (1) (student), Adam Daigneault (2), Keith S. Evans (3), Susan Gallo (4), Linda Bacon (5), Jianheng Zhao (6)

  1. Ecology & Environmental Sciences, University of Maine
  2. School of Forest Resources, University of Maine
  3. School of Economics, University of Maine 
  4. Maine Lakes
  5. Maine Dept. of Environmental Protection
  6. Center for Research on Sustainable Forests, University of Maine

Over the past 25 years, the Great Lakes and Ponds of Maine have faced challenges such as development, invasive species, and climate change, prompting a reassessment of their economic value to effectively guide conservation efforts. This study utilizes a range of methodologies such as travel cost modeling, expenditure analysis, surveys and hedonic price analysis to conduct a comprehensive assessment focused on recreation, water consumption, youth camps, and the impact of water quality on property values. We estimated that the total net economic value of Maine’s Lakes is nearly $14 billion, a 15% increase over the previous study, with the largest contribution coming from lakefront properties. An accompanying survey on perceptions of lake water quality emphasizes the importance of water clarity in recreation choices, with the average visitor indicating that they choose to visit lakes with water quality that is more than safe for swimming. This survey also highlighted that visitors have positive perceptions of Maine’s lake water quality, but costs and lack of accessibility create barriers to using these natural resources. Given these findings, our study emphasizes the need for Maine’s water bodies to be managed in a sustainable way that accounts for public perceptions of lakes and water quality. This poster will complement Dr. Zhao’s Session 10 presentation about potential impacts from water quality changes and focus on the team’s outreach campaign, which is designed to communicate the importance of including lake water quality values, economic valuation data, and public perceptions in environmental decision-making processes.

12. Utilizing Retired Lobster Traps as Artificial Reefs: Mitigating Ghost Fishing Impacts and Enhancing Marine Conservation

Deanna Gladstone (student), William Ellis
School of Marine Sciences, University of Maine

Poster withdrawn

13. Trust in Science and Institutions Among Residents of Maine

Melissa Godin (student), Caroline Noblet, Charity Zimmerman (student)
University of Maine

Trust in institutions and scientific research is critical to creating, implementing, and evaluating sustainability policy. Erosion of trust in science can drive policy and personal decision-making that is based on misinformation and vested interests rather than factual evidence. The continuation of scientific research that informs effective policy is also largely contingent upon public funding and confidence. National opinion polls conducted by the Pew Research Center show that trust in science, scientists, and public institutions has declined in the United States since the COVID-19 pandemic in 2020, particularly among certain demographic groups. Utilizing survey data collected by Dr. Caroline Noblet, Associate Professor of Economics at the University of Maine, we will compare attitudes and opinions of Maine residents regarding trust in science to these national trends. We will also examine how demographic variables such as education level, socioeconomic status, age, and others influence trust in science and institutions in Maine. Preliminary results show that there was a decline in trust among Maine residents post-COVID. However, recent survey data also suggests that state agencies, universities, and nonprofit organizations maintain higher levels of trust regarding science-based topics when compared to federal agencies among Maine residents. Understanding the factors that shape trust in science can equip researchers and policymakers with valuable insights to improve the acceptance and adoption of sustainable practices in Maine and beyond.

14. Zooplankton Sensitivity to Climate-Driven Conditions in High-Elevation Lakes in Maine

Sadie Gray standing by her winning poster
Sadie Gray, Winner of the Undergraduate Poster Award

Sadie Gray (student), Rachel Hovel
University of Maine Farmington

Lakes respond to climatic change with shifts in seasonality, stratification, primary production, biological community composition, and other conditions. Compared to larger lower-elevation lakes, “mountain” lakes are hypothesized to be more sensitive to some aspects of climatic change (e.g. watershed inputs from precipitation), but more buffered from others (e.g. snowpack stabilizing ice phenology). In this study of nine high-elevation lakes in the western Maine mountains, we evaluated the relationship between climate-linked lake conditions and zooplankton abundance and community composition. Water temperature, dissolved oxygen, chlorophyll concentration, ice breakup date, secchi disk depth, and zooplankton abundance and taxonomic identification were collected from these mountain lakes between 2018-2023. We used linear models to evaluate the relationships between abundance of different zooplankton taxa and lake conditions, and used multivariate analysis to identify community composition shifts across lake conditions. Depending on the taxonomic resolution, we identified differing responses to dissolved oxygen, primary production, and other lake parameters. These results illuminate the lake characteristics that most affect secondary production in these lakes, identify sensitivities of different taxa to different conditions, and provide tools to anticipate future zooplankton community composition in these changing systems.

15. Fostering Community Resilience: Learning From Maine’s Municipal Governments

Ruth Griffith (1) (student), Chloë Sheahan (2) (student), Kaitlyn MacPhee (3) (student), Kyle Pellerin (2)

  1. University of Maine
  2. Bowdoin College 
  3. University of Southern Maine

Community resilience is crucial as it enables societies to withstand, adapt to, and recover from challenges. Municipalities, especially in rural areas, can play a pivotal role in this process by providing essential services and support systems that fortify communities against sustainability challenges. Yet, relatively little is known about the role of municipal governments in fostering community resilience. In this research, we examined the provision of digital services and participation in state-funded community resilience grant programs by Maine municipal governments. Municipal digital services and grant capacities can enhance community resilience by strengthening communication, community engagement, planning, infrastructure, and services. We inventoried 484 municipal websites to assess the prevalence of 27 digital services and reviewed Maine’s Community Resilience Partnership annual reports to document community action grant activity. We used mapping and statistical analyses to assess municipal digital service offerings and resilience grant activity across the state. Given the importance of ensuring equitable community resilience, we evaluated the associations between these actions, population size, and per-capita income. Our findings reveal regional variation in these actions and indicate that higher digital service levels and community resilience partnership community action grants are positively correlated with population size and per-capita income. Our results also highlight exceptions to these overall demographic associations. By documenting the actions of Maine municipalities, this work begins to uncover how digital infrastructure and services and the ability to apply for and receive community resilience grants are related to demographic factors. These findings can inform strategies to foster resilience in Maine’s diverse communities.

16. How Much Will My Electric Bill Go Up if I Install a Heat Pump?

Nicole Grillo (student), Kelsey Flores (student), Matthew Hartt (student), Savannah Hustus (student), Tom Stone
Husson University

Some states, including Maine, have prioritized heat pump installations as a part of their overall plan to reduce greenhouse gas emissions. A key question for residential and commercial customers, as well as for electrical utilities, is how much additional energy will these heat pumps typically consume? To answer this, we analyze a four year data set consisting of pre- and post-installation electrical loading data from 155 residential customers in northern Vermont who installed a single heat pump; we find that the average electrical loading increases ~25% with the installation of a single heat pump. This key parameter (the average change in electrical loading per heat pump installed, based on real-world data) can better inform financial decision-making and electric grid planning.

17. Stream Water Geochemistry Near the Plumbago North Lithium-Bearing Pegmatite, West-Central Maine

Gil Hamilton (1) (student), Reusch, D. (1), Wieland L. (2), Felch, M. (3), Munk, L. (4), Bradley, D. (5)

  1. Department of Geology, University of Maine at Farmington
  2. Department of Chemistry, University of Alaska Anchorage
  3. Maine Mineral & Gem Museum
  4. Department of Geological Sciences, University of Alaska Anchorage
  5. Dartmouth College and U.S. Geological Survey

The Plumbago North pegmatite, located in west-central Maine, hosts spodumene crystals exceeding 11m in length. Preliminary drilling and bulk samples suggest that it contains >400,000 tons of Li2O (10 Mt at 4.68 wt% Li2O) worth approximately 1.5 billion USD and equivalent to the lithium needed to manufacture >16 million electric vehicle batteries. This study aims to develop a geochemical baseline of surface waters draining from the pegmatite deposit prior to development. We have collected samples seasonally six times between September 2022 and November 2023 from seven locations (Ellis River USGS Site 01054300, Howe Brook, four sites along Spodumene Brook, and a standing water pool in the Plumbago North quarry pit) to document spatial (e.g., proximity to quarry) and temporal (e.g., related to temperature and precipitation) variability. All samples have been analyzed at the University of Alaska Anchorage Applied Science, Engineering, and Technology (ASET) Lab for a broad suite of major and trace cations (ICP-MS) and major anions (IC). Most samples plot in the mixed cation-bicarbonate-rich field on a Piper diagram. Lithium concentrations in Spodumene Brook range from 2 times higher than outside of the watershed (Howe Brook and Ellis River; mean 2 ppb). The highest Li concentrations occur in the pit waters (55-167 ppb), well below the EPA-recommended threshold of 700 ppb. Trace levels of some ions enriched in pegmatites are present at very low concentrations (e.g., Rb 1-3 ppb). Ions of potential importance were also detected (e.g., As <0.2 ppb); significantly, U concentrations in Spodumene Brook are less than in the Ellis River (e.g., respectively 0.06 and 0.25 ppb). Our data set, which reveals slightly higher Li concentrations proximal to the quarry and ~2-fold seasonal variability attributed to dilution effects, should serve to guide future development and environmental monitoring.

18. Seasonal Variability of Peak Flow in Maine Rivers

Christopher Houdeshell (student), Brianna Benson (student), Salfa Hendrix (student), Kaylee Perron (student), Wyeth Purkiss (student), Emma Hovencamp (student)
Division of Natural Sciences, University of Maine Farmington

Rivers are integral components of Maine’s ecological and human communities, and are susceptible to climate change and direct anthropogenic impacts. River hydrology and flow regimes are affected by the surrounding landscape, precipitation patterns, and local impacts from dams and watershed development. Many rivers are experiencing hydrological changes, including changes in maximum flow, flow variability, and flow timing, and documenting these changes is important to understanding future trends. In this study, we analyzed four decades of historic flow data from the U.S. Geological Survey National Water Information System at four Maine rivers: two free-flowing rivers in western Maine and two coastal rivers with dam impacts. We identified changes in maximum flow and flow variability (coefficient of variation) at different times of year, and additionally evaluated changes in the timing of peak flow in spring and fall. We found different trends in flow variability between spring and fall, with stabilizing patterns in the spring and increasing flow variability in the fall and winter. The timing of maximum flow in the spring did not exhibit significant trends, and timing of fall peak flow trended generally later. Phenological differences in max flow and variability occurred between inland and coastal watersheds. These changes to river hydrology have implications for wildlife habitat, water supply, and human infrastructure. Anticipating future conditions, such as frequency of maximum flows, can assist in developing flood resilience and mitigating ecological and economic damage.

19. Quantifying the “Perfect Storm” for Sediment Entrainment at the Confluence of Nontidal Streams and Tidal Estuaries 

David J. Libby (1) (student), Sean M.C. Smith (1,2) and Bea Van Dam (1)

  1. School of Earth and Climate Sciences, University of Maine
  2. Sen. George J. Mitchell Center for Sustainability Solutions, University of Maine

Sediment mobilization by moving water has implications to aquatic habitats, water quality, public safety, and human health in waterways of Maine. The association of bacteria with sediment is one case where mobilization of particles by water flow can influence decisions related to closures of shellfish harvesting with implications to public health and wellbeing in coastal Maine communities. Previous research indicates bacteria can be absorbed to sediment particles, causing contamination beyond acceptable limits enforced by coastal resource managers in locations where particle entrainment occurs. The prediction and quantification of sediment entrainment in locations at the confluence of freshwater streams and estuary mud flats is challenging because of the variable conditions related to precipitation events, stream flow, and semidiurnal tidal fluctuations throughout the year. This research focuses on the convergence of conditions when sediment entrainment with contamination outcomes are most likely to occur in the confluence areas. Our study location is the confluence of Crippen’s Brook with the Jordan River estuary in Trenton, Maine. We describe and evaluate conditions coincident with relatively high vulnerability to sediment entrainment in the intertidal confluence area based on time series of stream flow and tidal conditions. Channel bottom sediment grain size and topographic measurements at the intertidal confluence are used with the time series data to perform analyses of the hydraulic conditions conducive to sediment mobilization. The analyses, performed at hourly time steps, are designed to identify and describe vulnerability to sediment mobilization, including the frequency that the conditions can become established in similar types of confluence settings. This research helps address a knowledge gap related to coastal sediment dynamics and a mechanism of contamination at the confluence of nontidal streams and tidal estuaries in Maine.  

20. Merrymeeting Gleaners Maine Community Fellowship

Liliana Lines (student)
Bowdoin College

Poster withdrawn

21. Schools as Sources of PFAS Contamination of Private Wells in Rural Maine Communities 

Ludwin Moran Sosa (1) (student), Ashley Taylor (2), Alexis Garretson (2), Ann Backus (3), Katie Richards (4) Joel H. Graber (2), Richard F. Hilliard (2), Jane Disney (2)

  1. College of the Atlantic
  2. MDI Biological Laboratory
  3. Harvard T.H. Chan School of Public Health
  4. Maine Laboratories

Poster withdrawn

22. The Impact of Phragmites australis (Cav.) Trin. ex Steud on Biodiversity, Emergent Biomass, and Nutrient Availability in a Salt Marsh Ecosystem

Lily Orth (student), Madeline McGlynn (student), Joseph Staples
Department of Environmental Science and Policy, University of Southern Maine

In this study, we investigated the ecological impact of the invasive wetland reed, Phragmites australis, commonly known as common reed or Phragmites, in Scarborough Marsh, Maine’s largest coastal marsh. Through a combination of field sampling and laboratory analysis, we compared the relative species composition, above-ground biomass, and elemental composition of soil and plant material collected from Phragmites-dominated stands and adjacent native grass stands. Our observations revealed a limited presence of native plant species within Phragmites-dominated stands, which aligns with the relevant literature describing Phragmites’ capacity to outcompete native marsh vegetation. Moreover, preliminary elemental analysis indicates a notable alteration in nutrient cycling dynamics and vegetation diversity within the impacted salt marsh ecosystem. Saltmarshes like Scarborough Marsh are essential habitats for diverse terrestrial and marine organisms. They also serve a critical function in coastal geomorphology by acting as a natural defense against flooding. However, the rapid spread of Phragmites australis in coastal areas necessitates continued research to fully grasp its impact on coastal ecology, stability, and infrastructure. This project highlights sustainability efforts by addressing the ecological implications of invasive species on coastal ecosystems. It emphasizes the need for proactive measures to preserve biodiversity and ecosystem resilience in the face of environmental challenges.

23. Calcium Availability and Brook Trout Stocking Interact to Shape​ Daphnia Relative Abundance in Northeastern Lakes

Gracie Scheve (1) (student), Mary Rogalski (1), Elizabeth Baker (1), Rachel Hovel (2)

  1. Bowdoin College
  2. University of Maine Farmington

Lakes in the northeastern U.S. vary considerably in the availability of dissolved ions such as calcium, sodium, and chloride. These ions are important for osmoregulation, and calcium serves as a structural micronutrient. Species have been shown to vary in their calcium requirements, and this variation could result in both direct and indirect effects on food web interactions. Daphniid zooplankton, which tend to have high calcium requirements, play an important role in lake foodwebs consuming microalgae and as prey for planktivorous fish. We explored how calcium availability and brook trout stocking practices may influence Daphnia dominance in crustacean zooplankton assemblages in the Northeastern United States. We sampled zooplankton and water chemistry in 29 Maine lakes along a calcium gradient and included data from an additional 62 New England lakes sampled by the U.S. Environmental Protection Agency. We predicted that Daphnia would become more dominant with increasing calcium levels. We also expected Daphnia to be rare in lakes stocked with brook trout, since young trout are voracious consumers of Daphnia. We observed a significant interaction between calcium availability and brook trout stocking in explaining Daphnia relative abundance in these lakes. Daphnia represented a larger fraction of the crustacean zooplankton community where calcium concentrations were above 3.25 mg/L, but only if brook trout were not stocked in that lake. This suggests that calcium limitation may strongly impact stocked brook trout populations, limiting their predation pressure on Daphnia. Further research on stocked brook trout reproduction and persistence may illuminate mechanisms behind our observed patterns.

24. Mammal Diversity of a Deciduous and Coniferous Forest in Southern Maine in Relation to Tick Density

Brady Speed (student), Sage Tocci (student), Joseph K. Staples
University of Southern Maine Environmental Science

The blacklegged tick Ixodes scapularis Say, is a common carrier of zoonotic pathogens in North America, including those responsible for Lyme disease. Due to the rising frequency of diseases transmitted by I. scapularis and its expanding range across the eastern U.S. and southeastern Canada, continuous research is necessary to understand the tick’s habitat preferences and its interactions with other species. Traditionally, pesticides and acaricides are applied to areas where ticks are expected to be abundant in an attempt to control their population, but these pesticides often come with negative environmental effects because of their frequent solubility in water. To negate the harmful impacts of conventional tick control methods, integrated pest management (IPM) methods have grown in popularity over the years. Essential to many successful IPM procedures is the monitoring and characterization of the wildlife population within the site where the procedure will be applied. In this study, the Adapted-Hunt Drift Fence Technique (AHDriFT) was used to monitor wildlife populations at two co-located sites in Wells, Maine to be compared to tick densities within both sites. The white-footed mouse (Peromyscus leucopus) was observed most frequently, with 231 instances evenly distributed across both stand types. The relative higher density of ticks in the deciduous site with similar occurrences of white-footed mice suggests that there are stand-level features that are controlling tick densities. Research is ongoing to better understand the ecological features that may be responsible for differences in relative densities of ticks and their small mammal hosts.

25. The Carbon Cycle in Hydroponic Farming

Samantha Summerfield (student), Emily Lesher
Saint Joseph’s College of Maine

Hydroponic farming is an innovative way to grow produce while saving water, nutrients, land, and energy. The Freight Farm at Saint Joseph’s College is a hydroponic agriculture system made in a 320 square feet recycled freight container. It uses ten gallons of water a day and the water is in a closed loop system. Nutrients are added to the water tanks when needed, which is adjusted based on automatic in-line sensors. The vertical grow-out technology allows for approximately 78,408 square feet or equivalent to 1.8 acres of land. The farm uses approximately 100 kWh of energy per day and has 128 high efficiency LED strips. Despite this, some hydroponic farms are considered less environmentally friendly than traditional farming due to its energy usage. Hydroponic farming requires an input and output of carbon equivalents to run properly. The cumulative energy demand is the sum of energy demand of all inputs required to produce a product (Martinez et al, ACS Sustainable Chemistry & Engineering, 2024). This measurement accounts for all energy inputs including the electricity and carbon dioxide generator. The outputs of carbon content can be quantified through the amount and quality of produce grown. For the Freight Farm, there is about 96 pounds of lettuce produced per month. The lettuce was sampled at different growth stages and using a UIC coulometer, the total carbon content was quantified. This research quantifies and compares carbon inputs, outputs and energy usage in order to better understand the sustainability of hydroponic farms.

26. Communicating Resilience: Innovative Rural Municipal Digital Communication

Dean Syed (1) (student), Elle Prescott (3) (student), Carter Frank (1) (student), Emma Olney (2) (student), Keeli Parker (1) (student), Addie Stone (3) (student), Jasmine Lopez (1) (student)

  1. University of Southern Maine
  2. Bowdoin College
  3. University of Maine

Community resilience is essential for town governments to be able to respond to and recover from sustainability challenges. One key component of resilience is the ability of a municipality to communicate information during a challenge. However, there is very little information about how and what rural communities communicate digitally in the United States. In this study, we aimed to identify innovative or high quality examples of digital communications by Maine municipalities. We developed a digital services inventory to identify the degree to which all Maine municipal governments provide digital information, use different digital platforms, offer municipal services digitally, and provide opportunities for digital democracy. We evaluated websites of all Maine municipalities, identified examples of innovative or high quality digital communication efforts, and reflected on the trends of these innovations. Our results showed four categories of innovative digital communication: collaborative online presences, civic and community engagement platforms, digital alert systems, and AI chatbots. These findings shed light on the diverse ways in which Maine’s municipalities offer services and information digitally, bolstering their community resilience. Not only does this research demonstrate the ability of some small rural towns to effectively communicate information and engage their residents, but it also provides insights into how other rural communities can improve their communication strategies to aid their populations and improve their overall resilience.

27. Post-Dam Removal Sediment Characteristics in Temple Stream, Western Maine

Carson Theriault (student), Julia Daly
Dept. of Geology, University of Maine Farmington

Temple Stream is a tributary of the Sandy River with high-quality spawning habitat for Atlantic salmon in its upstream reaches. In July 2022, a dam that created a mile-long impoundment in a downstream reach of the stream was removed, allowing water to flow freely for the first time in over 200 years. Several major flooding events in 2023 rapidly transferred sediment into, through, and downstream of the formerly impounded area, resulting in rapid change of sediment sizes present in and adjacent to the channel. Following the May 1 flood, and periodically through the summer and fall months, sediment samples were collected in the formerly impounded area every few weeks. Sediments were collected at multiple sites in three different positions: 1) channel levee; 2) channel margin (below bankfull stage); and 3) channel bed. Samples collected in 2023 allow comparison along transects from the levee across active point bars to channel bed, and also allow for comparison to previous years bed material (both pre- and post-dam removal). Following the high-water event in May, the previously impounded area showed adjustments in water depth, meander development, and increased mean size of bedload and adjacent point bar deposits. Levee and overbank deposits associated with the May flood were primarily fine sand, in contrast to silt and abundant organic material that formed marginal deposits when the area was impounded. Sand stored near the head of the former impoundment has been moving downstream, and was actively transported at lower flow levels in late summer and fall.

28. Comparing Tick Density Against Ground Dwelling Arthropod Diversity

Sage Tocci (student), Brady Speed (student), Joseph Staples
University of Southern Maine, Department of Environmental Science and Policy

The spread of Ixodes scapularis (the black-legged tick) across Maine has had substantial impacts on public health and the economy for the state since the early 1990s. Traditional chemical treatments used to control tick populations have relied on broad-spectrum insecticides and acaricides. Although chemical treatments are convenient and effective at managing ticks at the local scale, they can have a negative impact on non-target arthropod communities, possibly affecting naturally occurring tick predators as well. Additionally, negative impacts on human health, including chronic and acute health conditions, have been linked to the application of pesticides on the landscape. Varying half-lives, adsorption capacities, and solubilities between pesticide types creates a range of sources for the unintentional and unmonitored pesticide contamination, but waterways are a primary method of introduction into the environment. This has prompted researchers to consider how the relationship between tick populations, the broader arthropod community, and other ecological features, may help regulate tick populations. To explore these questions further, we deployed three transects of insect pitfall traps at two forested sites in southern Maine, one predominately composed of deciduous tree species and another predominantly composed of confer tree species, to collect ground dwelling insects and other arthropods. Standard flagging methods were used to collect and count ticks at each site. Results revealed that high tick densities within the the deciduous site were in contrast with the density and diversity of the broader insect and other arthropod community (Shannon Diversity Index for the conifer site was H =1.88, n=83; Shannon Diversity Index for the deciduous site was H =1.29, n=29). Further, predatory ground beetles (family Carabidae) accounted for 45.5% of all insects collected from the conifer site compared to 7% of insects collected from the deciduous site. Results obtained over the course of this study will inform further research which aims better to understand the complex dynamics between tick populations, arthropod communities, and ecological factors.


29. Can Freshwater Fisheries Provide Sustenance in an Age of Scarcity, Simplification, and Strife? A Biophysical Economic Analysis of Ice-Angling for Panfish in Central Maine.

Deborah Alademehin (1) (student), Stephen Coghlan (1,2)

  1. Department of Wildlife, Fisheries, and Conservation Biology, University of Maine
  2. Center for the Advancement of the Steady-State Economy (CASSE)

Resource depletion, pollution, climate heating, inflation, and sociopolitical unraveling are all indicators to the present and impending economic downturn that awaits humanity as ecological footprint downsizes to fit local, regional, and planetary carrying capacity. In response to this, some Mainers will turn directly to their local environment for sustenance through fishing, hunting, foraging, and other back-to-land activities. Hence, this research will investigate the capacity of ice-angling for Black Crappie and other Sunfishes to provide sustenance for Mainers during a future of scarcity, simplification, and strife. We are combining traditional fisheries science, social and biophysical economic analysis to assess the capacity of ice-angling to provide sustenance for Mainers.  Specifically, we will: 1) Use otoliths from harvested Panfish spanning 10+ years to infer vital characteristics of individuals and populations: survival, growth, longevity, age and size structure, and biomass production; 2) Incorporate results from otolith analysis with food web models to investigate capacity of local Panfish populations to feed Maine anglers; 3) Use biophysical economic models to explore various harvesting scenarios and estimate return on investment for individual anglers; and 4) explore how climate heating and economic shocks conspire to change angler behavior and harvest pressure. So far, ~2,000 otoliths showed diversity in ages (1-23 years), sizes (108-340mm). Under increasing harvest, we would expect to find earlier maturation, significant decline in mean age of harvested fish, evolutionary shifts of fish stocks. Eventually our study will compare protein demand of Maine anglers with productive potential of reference ponds and explore impacts of regulations/management prescriptions.

30. Physicochemical Factors Influencing Release of Per- and Polyfluoroalkyl Substances from Spent Granular Activated Carbon in Landfill Environments

Paulina Alulema-Pullupaxi (1) (student), Yi Zhang (2), Arjun Venkatesan (2,3), Navid Saleh (4), Onur Apul (1)

  1. Dept. of Civil and Environmental Engineering, University of Maine
  2. New York State Center for Clean Water Technology, Stony Brook University
  3. Dept. of Civil and Environmental Engineering, New Jersey Institute of Technology
  4. Dept. of Civil, Architectural and Environmental Engineering, University of Texas, Austin

Granular activated carbon (GAC) is a key method for removing per- and poly-fluoroalkyl substances (PFAS) from drinking water sources, but PFAS-laden GACs ultimately end up in landfills. This study investigates PFAS release from spent GACs in landfill environments, it examines how physical and chemical GAC properties influence two PFAS types (perfluorooctanoic acid – PFOA, and perfluorooctane sulfonic acid – PFOS) through standardized leaching tests: Multiple Extraction Procedure (MEP, Method 1320), Toxicity Characteristic Leaching Procedure (TCLP, Method 1311), and Australian Standards Leaching Procedure (ASLP, 2019). The goal is to compare these methods under simulated landfill conditions while deciphering the mechanism of PFAS leaching from spent GACs. Four GAC raw materials (bituminous, coconut, lignite, and wood) were assessed based on properties such as surface charge, pore size, surface area, and oxygen content. The study also considered the influence of PFAS type and concentration, as well as leachate chemistry (pH, ionic strength). Results indicated that physicochemical properties dictate adsorption mechanisms, capacity, and leaching rates. Higher oxygen content correlates with lower adsorption capacity and higher leaching rates for PFOA and PFOS. Leachate chemistry and PFAS functional group also determine leaching rates, with carboxyl groups exhibiting higher leaching than sulfonic groups under basic pH conditions typical of aged landfills. Thus, PFAS fate and transport in landfill settings interplay between GAC properties and environmental factors. 

31. The Relationship Between Extreme Precipitation and Stable Isotopic Values In Maine

Muhammad Drammeh (student)
University of Maine

Extreme precipitation is an issue that historically heavily affects agricultural industries and coastal communities in New England and Maine, and continues to do so. Previous studies have attempted to track the causes of extreme precipitation in New England, but have not been able to explain the specific upwards trend in extreme precipitation in the region during the winter. This study aims to use stable isotopic values to determine a causality behind this trend. Using MATLAB, we compared the Bangor International Airport and Roger’s Farm GHCN-d stations to ascertain the correlation in precipitation values during extreme events, finding no correlation, implying that extremity for these stations is largely a local event. We additionally compared these stations to CoCoRaHS stations, finding little correlation due to gaps in data and spacial variation. We now aim to compare extreme precipitation events in the Bangor International Airport and Roger’s Farm datasets to stable isotopic samples in their respective regions. The findings produced by this study have the potential to allow us to better understand the specific mechanisms by which extreme precipitation events occur within the New England region and address its effects on coastal and agricultural communities.

32. Suitability of the Native Wetland Bog Birch for Horticultural Landscapes

Jessica Hutchinson (student), Bryan Peterson, Stephanie Burnett
University of Maine

Incorporating additional native plants that can adapt to predicted changes in climate is a way to preserve and strengthen landscape biodiversity and resilience in ornamental landscapes. We evaluated methods to propagate a novel Maine native shrub, bog birch (Betula pumila), for use in horticultural landscapes. We also investigated the physiological responses of this wetland shrub to water deficit, a condition expected to increase in frequency and duration as climates change. In July 2023, we collected softwood stem cuttings of wild bog birch, treated them by dipping them into water or indole-3-butyric acid (K-IBA), and rooted them under intermittent mist. In a second study, we imposed a controlled drought on 1-year-old bog birch growing in #1 nursery containers. Drought severity was increased weekly using precision irrigation in a greenhouse to decrease volumetric water content (%). Cuttings treated with any concentration of K-IBA from 1,000 to 5,000 ppm yielded 69% transplantable cuttings, while untreated cuttings produced inferior measures of rooting. Bog birch survived moderate drought, and maintained their aesthetic value at substrate moistures as low as 10%. Under severe drought (5% moisture), shrubs lost a significant portion of foliage. Bog birch can be propagated easily, grows well in containers, and maintains aesthetic features under moderate drought conditions. Results support future consideration for bog birch as a promising native ornamental shrub in Maine. This broadens the selection for consumers as Maine shifts towards climate conscious ornamental landscapes with native wildlife value.

33. Analyzing Measured Flows for Salmon Habitat Management in the Upper Penobscot River

Cade King standing by his winning poster
Cade King, Winner of the Graduate Poster Award

Cade King (1) (student), Bea E. Van Dam (1), Sean M.C. Smith (1,2)

  1. School of Earth and Climate Sciences, University of Maine
  2. Senator George J. Mitchell Center for Sustainability Solutions

Civil infrastructure related to freshwater flows is often constructed to meet industrial, recreational, and hazard management demands. Structures such as dams and canals can enhance surface water storage, create water supply sources, generate energy, and regulate flood flows to manage hazards. However, the constructed features can alter hydraulic conditions in river channels by reducing responses to runoff and changing hydrologic regimes. This can impact aquatic habitat for vulnerable organisms like diadromous fish. In the 19th and 20th centuries, dams, canals, and sluiceways were constructed throughout Maine’s Penobscot River system to transport copious quantities of logs and produce power. Today, the drainage network of the Penobscot’s East Branch remains dammed in multiple locations, and flow from the headwaters of the St. John River is rerouted into the East Branch through the Telos Canal. Modern management decisions regarding the future of the Penobscot’s headwaters require consideration of this infrastructure, aquatic habitat impairments, societal needs, and forecasted climate changes. Assessment of infrastructural impacts and quantification of the river’s responses to restoration scenarios is required for stakeholder-led restorative action. Hydrologic and hydraulic conditions in the Penobscot’s East Branch are being simulated using the U.S. Army Corps of Engineers’ HEC-RAS and HEC-HMS modeling platforms. The simulations consist of comparative responses to varied habitat restoration scenarios involving a range of dam management alternatives. Here, we summarize preliminary research outcomes focused on assembly of knowledge, spatial information, and hydrologic measurements related to the East Branch in the context of multi-objective river management interests.

34. Dreaded and Unknown: Online Risk Communication and Polyfluoroalkyl Substances (PFAS)

Carrie Loomis (1) (student), Laura Rickard (1), Amelia Couture Bue (1), and Janet Yang (2) 

  1. University of Maine, Department of Communication and Journalism
  2. University at Buffalo, Department of Communication

Polyfluoroalkyl substances (PFAS), chemicals known for their durability and variety of applications, are attracting increased attention due to their environmental and health risks. However, little is known about how PFAS risks are communicated to affected communities. In this research, we use quantitative content analysis to explore how PFAS risks are represented on public webpages in the U.S. (N = 64). We also use integrative framing analysis to examine the congruences or differences in images and texts on these webpages. Results suggest that, across all websites, efficacy information often appears with statements that invoke dread, specifically by implying that PFAS can pose a threat to the individual or be inequitable in who is affected. On websites published by government organizations, references to the PFAS nickname, “forever chemicals”, are less common than on non-government websites. Government websites also discuss PFAS at a state level more. On websites at the national level, efficacy information, references to farms or farmers, discussions of individual states, and mention of testing or water treatment are less common than on state- or local-level websites. Lastly, across all websites, average congruence between text and images portrayed was significantly higher for references to/images of farms or farmers in comparison to several other common PFAS sources (i.e., firefighting foam, water/stain resistant material, packaging, and cookware). For practitioners, this research opens a dialogue about the utilization of the psychometric paradigm and efficacy information to encourage protective behavior and create conversation surrounding PFAS.

35. Investigating the Effects of Soil and Plant Characteristics on Soil-to-Plant PFOS Transfer Factors in Perennial Forage Systems Across Maine

Sonora Ortiz (1) (student), Ellen Mallory (1), Jean MacRae (1), Thomas Simones (2), Andrew Smith (2)

  1. University of Maine
  2. Maine Center for Disease Control and Prevention

Perfluorooctane sulfonic acid (PFOS) is an emerging health risk linked to carcinogenic and immunotoxic effects, among others. A major route of human exposure is through milk and beef from cows fed with hay contaminated as a result of historic sludge spreading on farm fields. Soil-to-plant transfer factors, quantifications of PFOS uptake by plants, are highly variable from site to site and even field to field on a given farm. In this study, we sought to find connections between various soil and plant characteristics and this variability in transfer factors from 25 sites across Maine. Some of the soil parameters considered include texture, pH, and total organic carbon; some of the plant parameters include crude protein, lignin, and starch. Co-located soil and plant samples were taken and submitted for PFOS, soil fertility, and forage quality analyses. PFOS levels were determined using the Department of Defense Quality Systems Manual 5.1 (DoD QSM 5.1) method with plant samples undergoing cryogrinding prior to analysis. Soil fertility tests included those using the Mehlich 3 extractant. Forage quality analysis was conducted using near-infrared spectroscopy. A combination of standard statistical analysis as well as principal component analysis was used on the data. Preliminary results suggest that the concentration of exchange sites in the soil explains the largest portion of the variability in our data set and is negatively related to PFOS transfer factors.

36. Scaling up Agroforestry: Private Nursery Manager’s Perspectives

Alaina Ring (student)
University of Maine

In the coming decades, the intensification of climate change will render agriculture increasingly vulnerable, putting farmer livelihoods and food security at risk. To meet this challenge, it is imperative that we scale up sustainable agricultural systems such as agroforestry. There are a wide variety of barriers to adopting agroforestry in temperate regions, including high up-front costs, a limited number of knowledgeable land management professionals, and an economic pressure towards large-scale, monoculture cropping systems. For the purpose of this study, we focus specifically on the lack of appropriate plant material for agroforestry systems. In collaboration with the USDA National Agroforestry Center, this research study was designed to identify barriers to scaling up plant production for agroforestry in the US, with a specific focus on the role of private nurseries in the plant material pipeline. Interviews were conducted with nurseries located in 16 different states across the U.S. and fill a significant knowledge gap regarding the capacity to scale up agroforestry. Nineteen interviews generated in-depth observations about barriers to plant production, insights into the species selection process, and identified overarching challenges faced by the nursery industry. Results indicate that nurseries are eager to fill demand but are limited by a lack of knowledge about agroforestry and demand for plant material. In addition, nurseries face a multitude of challenges related to workforce recruitment and development and financing models that are not tailored to the specific needs of plant nurseries.


37. PFAS in Maine’s Coastal Waters

Christoph Aeppli (1), Amanda Pinson (1), Shane Farell (1), Dara Yiu (1) Heather Kenyon (2), Mike Doan (2), Ivy Frignoca (2)

  1. Bigelow Laboratory for Ocean Sciences 
  2. Friends of Casco Bay

To fill a knowledge gap related to per- and polyfluoroalkyl substances (PFAS) in coastal environments, we collected water samples along Maine’s coast and analyzed them for 40 PFAS compounds. The stations include water quality monitoring sites across Casco Bay, which were sampled monthly in 2023, an additional 30 coastal sites from Portland to Machias, which were sampled once, and samples along the lower Kennebec River and close to a known PFAS source site. PFAS were detected in all analyzed samples at low but detectable levels. Casco Bay and the other coastal samples had an average concentration of 3.6±2.3 ng/L (range: 0.4 to 14 ng/L) for total PFAS. Samples collected along the Kennebec River were somewhat higher, which was not surprising given the terrestrial sources of PFAS. Lastly, PFAS concentrations close to a known release site were highest but rapidly decreased further offshore due to dilution. Distinct and likely source-specific PFAS profiles were observed for several locations. Overall, these findings show that low PFAS concentrations can be detected throughout Maine coastal environments and that several sources likely contribute to this PFAS input.

38. Case Study of PFAS Detective Work in a Coastal Maine Community

Michelle L. Berger, Charles Rolsky
Shaw Institute

Per- and polyfluoroalkyl substances (PFAS) are used to repel oil and water in commercial products and they have been linked to many negative health effects. These chemicals have been detected throughout Maine in soil, water, and biota. In 2021, Maine passed a mandate to test all public water systems, including schools, for PFAS and it set a threshold for contamination. As a result, many small schools without access to municipal water discovered PFAS contamination in their wells. After one such discovery at the elementary school, the town of Surry, ME, chose to further investigate the possible sources and extent of PFAS pollution in the community. Cyclopure PFAS Water Test Kits were used to test streams, municipal buildings, and private residences. Additionally, based on residents’ anecdotal reports, soil was tested at the soccer field and on the school property. Elevated PFAS levels were discovered in a stream near the soccer field, a town park well, and in a few private residences. PFAS were also found in the topsoil of the soccer field and in the school’s former leach field. It was determined that undocumented biosolid spreading is a likely source of well and stream water contamination. However, a unique contamination profile in the school’s well indicates that there may be other sources within the school itself. Inclusion of community members and leaders is critical for success of contamination detective work. This study can serve as a model for other small communities in Maine and beyond following the discovery of PFAS contamination.

39. The Behavior of PFAS in Lab-Scale Stormwater Treatment Systems

Richard F. Hilliard (1), Bethany A. Parker (2), Staci L. Massey Simonich (2), Jennifer A. Field (2), Tyler Radniecki (2)

  1. MDI Biological Laboratory
  2. Oregon State University

Concerns about stormwater quality have increased as population centers grow in magnitude and density, further impacting the quality of receiving water bodies. Per- and polyfluoroalkyl substances (PFAS, sometimes called ‘forever chemicals’) are ubiquitous in the natural environment, including stormwater runoff. This greenhouse experiment demonstrates the behavior of PFAS of varying lengths (3-10 fluorinated carbons) and functional groups (carboxylates, sulfonates, and sulfonamides) in lab-scale planted green-infrastructure systems. For ten weeks, six replicates each of 10 different plants were grown in 3.78 L high-density polyethylene buckets in a mixture of soil, sand and gravel and dosed once per week with collected stormwater which was spiked with 1.000 µg per liter of total PFAS. Contact time between the stormwater and the soil was five hours after which the systems were drained, and the effluent was composited and analyzed. After ten weeks, each experimental unit was separated into soil, roots, leaves, stems, and weeds and analyzed. Samples were analyzed using a combination HPLC-MS/MS and HPLC-QToF. Most PFAS are captured by the soil, secondarily passing through the system in the effluent, and are only marginally concentrated in the roots and shoots of the plants. Distribution across these different compartments, including the differences observed between above and below ground parts of the part, are strongly influenced by molecule size (molar volume) and their water/organic carbon partition coefficient (Koc).

40. Mothbusters Battling the Brown-tail Bother: A Web of Solutions from an Academic – Municipal Partnership Weaves Through Waterville, Maine

Thomas Klepach (1,2), Tahiya Chowdhury (3), Carrie Nguyen (4)

  1. Science, Technology, and Society Department, Colby College 
  2. Ward 3 Waterville City Councilor
  3. Davis Institute for Artificial Intelligence, Colby College
  4. Computational Biology, Studio Art, Colby College

Brown-tail Moth (BTM, Euproctis chrysorrhoea) is an environmentally destructive introduced species with few native biological controls that poses a direct threat to human health, ecosystem integrity, and can have significant economic impacts. Introduced to New England in the late 19th century, the most recent episodic outbreak began in 2015 and moved into Central Maine in 2019 due to climate cues. The City of Waterville in partnership with Colby College, collected a highly spatially resolved dataset of infestation within Waterville city limits during the winters of 2021-2022 and 2022-2023. This dataset was used to implement a comprehensive treatment strategy on both public and private lands. Ongoing research seeks to lower the cost of collecting infestation data using drone canopy footage analyzed by AI. Another area of ongoing research has been exploring the correlation between the intensity of light pollution, proximity to suitable food sources, and the geospatially resolved infestation data to develop an index that can guide effective and efficient implementation of light pollution mitigation policy with an eye towards limiting the infestation potential in Waterville. Results indicate that the collection of landscape scale drone footage when analyzed with trained AI presents a lower cost option for the identification of BTM infested specimens than contract arborists. Also, a unitless index was developed that identifies areas most susceptible to BTM infestation based on proximal canopy cover and intensity of light pollution. This index can guide policy around light mitigation efforts aimed at limiting potential BTM infestation. Current analysis of ongoing work will be presented.

41. Improving Stream Assessment for Trout and Salmon Restoration in Appalachian Mountain Club’s Maine Woods Initiative

Braedon C. Lineman (1), Cathy Poppenwimer (1), Miriam Ritchie (1,2), Sarah J. Nelson (1), Carolyn Ziegra (1)

  1. Appalachian Mountain Club
  2. The Terrain Project, Denver, CO

The Appalachian Mountain Club (AMC) has been working to protect and enhance brook trout and endangered Atlantic salmon habitat on our 114,000-acre property in the 100-Mile Wilderness region of Maine. Since 2011, 132 fish passage restoration projects have been completed and 128 stream miles have been reconnected on the AMC’s Maine Woods Initiative property. Through this work, AMC staff recognized that many stream systems were not portrayed accurately in publicly accessible data resources. Practical experience suggested that the streams were longer than what were reported in databases, such as the U.S. Geological Survey National Hydrology Dataset (NHD, USGS 2019), frequently used by landowners and state and federal resource management agencies. In 2020, a pilot project was conducted to focus on developing a stream delineation model to map the small upland stream channels using finer-scale elevation models more accurately. In 2022 and 2023, we focused on improving the model by providing a larger sample size for comparison and to develop a more refined, spatial data-based model that would more accurately estimate stream lengths. The NHD was inaccurate at fine scales and in the remote forested areas in Maine. We found that NHD missed four of 13 streams we ground-truthed and the offset (position) of streams was in error by an average of 39 feet when compared to ground-truthed data. Improvement of the stream and wetland delineation is needed to further provide direct evidence of ample stream habitat upstream of crossing barriers and help with operational and financial planning.

42. Fingerprinting the Belgrade Lakes by 31P-NMR

Casey O’Connor, D. Whitney King
Colby College

In the freshwater ecosystem of the Belgrade lakes, late-summer algal blooms are accelerated by an increase in phosphorous concentration. Living systems depend on a variety of chemical forms of phosphorous, from nucleotides that provide the genetic code and metabolic energy to phospholipid layers that define the cellular environment. Phosphorous incorporated into phosphate ions is preferentially scavenged from the aqueous environment by microorganisms. For practical reasons, phosphorus concentrations in lakes are typically measured as total phosphate after chemical oxidation of all forms of phosphorus.  In this work we apply nuclear magnetic resonance spectroscopy (NMR), to “fingerprint” the molecular forms of phosphorus in the Belgrade Lakes sediments and water column. Changes in phosphorus speciation with time will help assign a eutrophication risk factor for each lake and also understand the effectiveness of alum complexation of phosphorus in the sediments.

43. Assessing the Feasibility of Establishing an Automated Snow Monitoring Network in the Northeast Mountains

Kyler Phillips (1), Joshua Beneš (2), Elizabeth Burakowski (3), Jordan Clayton (4), Alix Contosta (3), Heather Hofman (5), Cara McCarthy (5), Scott McKim (6), Georgia Murray (1), Chris Nadeau (7), Sarah Nelson (1), Erika Rowland (8), Melissa Webb (5)

  1. Appalachian Mountain Club
  2. University of Vermont
  3. University of New Hampshire
  4. USDA NRCS Utah Snow Survey
  5. USDA NRCS National Water and Climate Center
  6. New York State Mesonet and SUNY-Albany
  7. Schoodic Institute 
  8. Forest Stewards Guild 

The Northeastern U.S. has lost 19 snow-cover days since 1917, and at one New Hampshire site, annual snowfall has declined by 1.7 m since 1935. Changes to the region’s winter climate trigger wide-ranging environmental, economic, and social impacts. Mountain communities can be disproportionally affected, through shifting snowmelt and flood regimes and their dependence on winter-based tourism; however, most snow data in the region are obtained at lower-elevation sites. In the western U.S., the U.S. Dept. of Agriculture Natural Resources Conservation Service (NRCS) operates SNOTEL, an automated network of over 890 snow and weather monitoring sites that informs resource management, including water supply forecasting and flood risk mitigation. The Northeast lacks an equivalent network, limiting the ability of interest-holders to understand and respond to changing mountain conditions. We are conducting a feasibility study, the Northeast Snow Survey (NESS), for the establishment of a coordinated, automated snow monitoring network in the Northeast. NESS seeks to design a network to monitor weather and hydrological variables across elevational gradients, facilitating improved flood and streamflow forecasting, climate modeling, and resource management. We are completing the interest-holder engagement phase of the project. Initial outreach has engaged diverse interest-holders, including climate and ecological researchers, weather and hydrological forecasters, and resource and recreation managers. We are inventorying established monitoring sites in the region to inform potential siting. Future phases will include identifying new site locations, formalizing partnerships, and coordinating implementation with NRCS. We invite conference attendees to share insights, particularly regarding interest-holder engagement, existing data, siting considerations, and network implementation.

44. BIL, ARPA and IRA… Dams, Culverts and Fish, OH MY!: What MEDMR Is Doing in Restoration

Theodore Willis, Sean Ledwin, Casey Clark, Lars Hammer
Maine Dept. of Marine Resources, Bureau of Searun Fish and Habitat

All of the major diadromous fish plans clearly identify barriers to fish passage as impediments to restoring these species to their native habitat. The American Rescue Plan Act (ARPA), Bipartisan Infrastructure Law (BIL) and Inflation Reduction Act (IRA) have allowed Maine Dept. of Marine Resources (DMR) to lead an effort coordinating and partnering with multiple non-governmental orgainzations, Maine’s Tribal communities and other State of Maine entities to remove, replace and rehabilitate fish migration barriers. ARPA gave $195 billion to states for discretional use during the pandemic. The State of Maine allocated DMR $8 million for fish habitat connectivity projects. BIL funding increased by 10-20x many of the annual funding competitions released by National Oceanic and Atmospheric Adminstration (NOAA) that fund restoration projects. DMR requested funding for Aquatic Organism Passage (AOP) culvert replacements with the Maine Dept. of Transportation (DOT) and the Passamaquoddy Tribe, implementation funding for a slew of projects where designs were paid for using ARPA funding, and other projects that improved passage conditions on small coastal streams. The IRA includes $3 billion for coastal habitat protection, which produced a one-year windfall in NOAA programs that already had record funding the year before. If all projects are funded as of December 2023 submissions, DMR and partners will restore access to more than 1,136 miles of stream, including 7,891 modeled salmon habitat units, 105,779 acres of lake habitat (that could produce as many as 42 million adult alewives) and 63 acres of coastal marsh habitat. Other exciting projects where DMR is a supporter would exceed this number. All projects are valued at $150M in submissions as of Dec. 2023.