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Full-Text Articles in Environmental Policy

When Words Flow Like Water: How The Enbridge Line 3 Pipeline Environmental Impact Statement Failed To Prevent Hydrogeologic Harm In Minnesota, Carly Gutzmann Jan 2026

When Words Flow Like Water: How The Enbridge Line 3 Pipeline Environmental Impact Statement Failed To Prevent Hydrogeologic Harm In Minnesota, Carly Gutzmann

Journal of Earth and Life Science

For the aquifers of Minnesota, the environmental impact statement (EIS) was a promise of protection that never left the page. An environmental impact statement is meant to be an aid in the decision making process in order to ensure that projects consider potential environmental harms that may occur. However, they are often used instead as another regulatory box to check, rather than as active considerations when planning. As such, a project plan can be flawed from the start—if project developers only consider environmental impacts after they have already put considerable time, effort, and funding into their project as-is, they may …


Powering The Machine, Draining The Planet: Whether U.S. Environmental Law Is Equipped To Regulate The Energy And Water Demands Of Ai Data Centers, Michael Marcu Jan 2026

Powering The Machine, Draining The Planet: Whether U.S. Environmental Law Is Equipped To Regulate The Energy And Water Demands Of Ai Data Centers, Michael Marcu

Journal of Earth and Life Science

Artificial intelligence (AI) data centers have become one of the United States' fastest-growing and least-regulated sources of environmental stress. In 2024 alone, U.S. data centers consumed 183 terawatt-hours (TWh) of electricity more than the entire nation of Pakistan and consumed an estimated 17 billion gallons of water (IEA, 2025; Berkeley Lab, 2024). By 2030, electricity demand from these facilities is projected to reach 426 TWh, a 133% increase in six years (Pew Research Center, 2025). This paper examines whether the existing U.S. environmental regulatory framework put by the National Environmental Policy Act (NEPA), the Clean Water Act (CWA), and the …


Recent U.S. Government Policy Literature On Critical And Strategic Minerals, Bert Chapman May 2025

Recent U.S. Government Policy Literature On Critical And Strategic Minerals, Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Critical and strategic minerals have become increasingly important in U.S. government civilian and military policymaking in recent years. This is demonstrated by the heavy use of such minerals in many critical civilian and military infrastructures. This work will discuss how this subject has been addressed in laws, presidential documents, and works by government agencies along with congressional oversight committees and support agencies. It will stress how the United States is heavily dependent on strategic minerals from adversarial foreign countries such as China and will examine U.S. efforts to increase its ability to produce such materials in the United States by …


Community Land Governance In Liberia: Implications For Tenure Security And Land Concessions, Julia R. Entwistle, Hanson Nyantakyi-Frimpong Apr 2025

Community Land Governance In Liberia: Implications For Tenure Security And Land Concessions, Julia R. Entwistle, Hanson Nyantakyi-Frimpong

Geography and the Environment: Faculty Scholarship

Throughout rural Africa, the intersection of customary traditions and statutory governance has often led to overlapping jurisdictions and conflicts over community land rights. In Liberia, this dynamic is particularly evident in the rise of commercial land concessions. This article examines the Liberian government’s approach to community land rights and its impacts on land tenure security, especially in the context of these concessions. This study employs a discourse analysis of Liberian land use policies alongside qualitative data from in-depth interviews with community members living near large-scale plantations. Despite historical erosion of community land rights, Liberian communities have adapted statutory frameworks to …


Three Essays On Sustainability Economics, Hélène Flore Nguemgaing Jan 2025

Three Essays On Sustainability Economics, Hélène Flore Nguemgaing

Graduate Theses, Dissertations, and Problem Reports (ETD)

As global economies face increasing resource dependencies and supply chain challenges, it becomes essential to understand the vulnerabilities that threaten economic stability. This dissertation investigates three empirical issues in agribusiness and critical minerals using econometric models to estimate the following: 1) the impact of supply chain disruptions on stock market returns during COVID-19; 2) the extraction of rare earth elements from acid mine drainage treatment by investigating the impacts of ownership and legislation in West Virginia and Pennsylvania; 3) China-to�FOBb (Free-on-Board) price transmission in rare earth elements markets: a copula-based dynamic tail dependence analysis.

The first essay evaluates how events …


Effects Of Round-Up On The Environment, Sandra J. Marcu Jan 2025

Effects Of Round-Up On The Environment, Sandra J. Marcu

Journal of Earth and Life Science

Many people around the world have used and still currently use Roundup but are unaware of the effects it has on the environment. Roundup is a spray on application weedkiller that is widely used around the world today both residentially and commercially. It enables its user to grow a garden or a field of crops with a no-tilling approach to eliminate weeds. It is a well-known and popular choice for killing weeds that has been around since the mid 1970’s (Oca, 2017). John Franz, a Monsanto scientist discovered that glyphosate (main ingredient in Roundup) was an herbicide or weedkiller, and …


The Effectiveness Of The Minnesota Buffer Law And Its Impacts On People, Ellen P. Isakson Jan 2025

The Effectiveness Of The Minnesota Buffer Law And Its Impacts On People, Ellen P. Isakson

Journal of Earth and Life Science

In January 2015, the then-governor of Minnesota Mark Dayton announced new legislation that would require 50-foot vegetation buffers along all waterways in Minnesota; this legislation would come to be known as the Minnesota buffer law, exact requirements being “perennial vegetative buffers of up to 50 feet along lakes, rivers, and streams and buffers of 16.5 feet along ditches” (Albert, 2017; MN Board of Water and Soil Resources [MN BWSR] 4 ). A buffer in the context of vegetation and natural resource management is a strip of vegetation around a body of water “designed to intercept stormwater runoff and minimize soil …


Navigating Murky Waters: State-Level Strategies For Wetland Preservation And Tile Drainage Regulation After Sackett V. Epa, Caleb M. Swanson Apr 2024

Navigating Murky Waters: State-Level Strategies For Wetland Preservation And Tile Drainage Regulation After Sackett V. Epa, Caleb M. Swanson

Honors Thesis

Wetlands are some of the world’s most valuable ecosystems, serving as provisioners of species habitat, carbon sequestration, flood mitigation, water quality purification, and other ecosystem services. Human development has resulted in substantial wetland loss the world over. In the 1970s, the United States Congress passed the Clean Water Act, giving the EPA broad authority over wetland protection. However, in the summer of 2023, the United States Supreme Court decided Sackett v. EPA, limiting the EPA’s jurisdiction over wetlands to those indistinguishably connected to generally recognized “Waters of the United States” and removing federal protection for millions of acres of wetlands, …


Three Essays On Energy Related To State Policies And Low Carbon Transitions, Pinky Thomas Jan 2024

Three Essays On Energy Related To State Policies And Low Carbon Transitions, Pinky Thomas

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation consists of three essays on energy-related state policies and energy transition. Each paragraph below refers to the three abstracts for the three chapters in this dissertation, respectively.

The first essay is entitled: “Impacts of State Tax and Resource Ownership Policies on Extraction: Evidence from U.S. Natural Gas Production”. The innovation of combined use of horizontal drilling and hydraulic fracturing technologies during the 2000s has allowed natural gas producers in the United States to extract natural gas and liquids from deep shale formations in a cost-efficient manner. This essay evaluates whether unconventional gas production responds to tax changes, and …


Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia Dec 2023

Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia

Journal of Nonprofit Innovation

Urban farming can enhance the lives of communities and help reduce food scarcity. This paper presents a conceptual prototype of an efficient urban farming community that can be scaled for a single apartment building or an entire community across all global geoeconomics regions, including densely populated cities and rural, developing towns and communities. When deployed in coordination with smart crop choices, local farm support, and efficient transportation then the result isn’t just sustainability, but also increasing fresh produce accessibility, optimizing nutritional value, eliminating the use of ‘forever chemicals’, reducing transportation costs, and fostering global environmental benefits.

Imagine Doris, who is …


Self-Reported Consumption Of Bottled Water V. Tap Water In Appalachian And Non-Appalachian Kentucky, Jason W. Marion Aug 2023

Self-Reported Consumption Of Bottled Water V. Tap Water In Appalachian And Non-Appalachian Kentucky, Jason W. Marion

Journal of Appalachian Health

Introduction: Quantitative studies on drinking water perceptions in Appalachia are limited. High-profile water infrastructure failures in the U.S. and Eastern Kentucky, coupled with human-made and natural disasters in the Appalachian Region, have likely impacted opinions regarding tap water.

Purpose: To use existing unexplored data to describe baseline tap water v. bottled water consumption in Kentucky.

Methods: Telephone-based cross-sectional data were obtained from the 2013 Kentucky Health Issues Poll (KHIP) directed by the Foundation for a Healthy Kentucky. Among many items in KHIP, self-reported consumption of bottled water over tap water, reasons for bottled water use, and demographic data were obtained. …


Quantifying The Carbon Stored And Sequestered By The Trees On Pomona College’S Campus, Paola A. Giron-Carson Jan 2023

Quantifying The Carbon Stored And Sequestered By The Trees On Pomona College’S Campus, Paola A. Giron-Carson

Scripps Senior Theses

We are experiencing a climate crisis that must be confronted with strategic mitigation. Pomona College contributes to the climate crisis through its emissions for which there is a baseline record. However there is no baseline record of the climate mitigation currently performed by the trees on Pomona’s campus through carbon storage. This study seeks to determine a current baseline quantity of carbon stored and sequestrated by Pomona’s trees as well as possible courses of climate mitigation for Pomona College to take. Initial information gathering was conducted through interviews with several stakeholders. This study was conducted using data collected prior to …


Recommendations For Sustainable Tourism In Patagonia: An Exploratory Analysis Of Sustainable Tourism In Costa Rica, The Nordic Region, And Thailand’S Communities, Julia K. Lowery Dec 2022

Recommendations For Sustainable Tourism In Patagonia: An Exploratory Analysis Of Sustainable Tourism In Costa Rica, The Nordic Region, And Thailand’S Communities, Julia K. Lowery

Undergraduate Honors Theses

This thesis explores different levels of governance and its role towards actualizing sustainable tourism in Patagonia. With the growing threat of climate change, international destinations such as Patagonia are looking to continue building their tourism industries in a sustainable way. Through analyzing case studies of national governance in Costa Rica, multi-national governance in the Nordic region, and community-based tourism in Thailand, we can better understand how each form of governance has the potential to create a sustainable tourism industry. With this understanding of successful governance in my case studies, as well as understanding the historical and political forces that have …


Ecological Risk Assessment Of Managed Relocation As A Climate Change Adaptation Strategy, Aviv Karasov-Olson, Mark W. Schwartz, Julian D. Olden, Sarah Skikne, Jessica J. Hellmann, Sarah Allen, Christy Brigham, Danielle Buttke, David J. Lawrence, Abraham J. Miller-Rushing, Jeffrey T. Morisette, Gregor W. Schuurman, Melissa Trammell, Cat Hawkins Hoffman Mar 2021

Ecological Risk Assessment Of Managed Relocation As A Climate Change Adaptation Strategy, Aviv Karasov-Olson, Mark W. Schwartz, Julian D. Olden, Sarah Skikne, Jessica J. Hellmann, Sarah Allen, Christy Brigham, Danielle Buttke, David J. Lawrence, Abraham J. Miller-Rushing, Jeffrey T. Morisette, Gregor W. Schuurman, Melissa Trammell, Cat Hawkins Hoffman

United States National Park Service: Publications

Executive Summary

Changing climate and introduced species are placing an increasing number of species at risk of extinction. Increasing extinction risk is increasing calls to protect species by relocating, or translocating, them to locations with more favorable biotic or climatic conditions. Managed relocation, or assisted migration, of species entails risks to both the conservation target organisms being moved as well as the recipient ecosystems into which they are moved.

Recognizing this risk, calls have been made for practitioners interested in considering a managed relocation project to engage in a serious risk assessment prior to advancing a project. We engaged a …


Protocol For Monitoring Fish Communities In Small Streams In The Heartland Inventory And Monitoring Network, Version 2.0, Hope R. Dodd, David G. Peitz, Gareth Rowell, Janice A. Hinsey, David E. Bowles, Lloyd W. Morrison, Michael D. Debacker, Jennifer L. Haack-Gaynor, Jeffrey M. Williams Mar 2021

Protocol For Monitoring Fish Communities In Small Streams In The Heartland Inventory And Monitoring Network, Version 2.0, Hope R. Dodd, David G. Peitz, Gareth Rowell, Janice A. Hinsey, David E. Bowles, Lloyd W. Morrison, Michael D. Debacker, Jennifer L. Haack-Gaynor, Jeffrey M. Williams

United States National Park Service: Publications

Executive Summary

Fish communities are an important component of aquatic systems and are good bioindicators of ecosystem health. Land use changes in the Midwest have caused sedimentation, erosion, and nutrient loading that degrades and fragments habitat and impairs water quality. Because most small wadeable streams in the Heartland Inventory and Monitoring Network (HTLN) have a relatively small area of their watersheds located within park boundaries, these streams are at risk of degradation due to adjacent land use practices and other anthropogenic disturbances. Shifts in the physical and chemical properties of aquatic systems have a dramatic effect on the biotic community. …


Protocol For Monitoring Aquatic Invertebrates Of Small Streams In The Heartland Inventory & Monitoring Network, Version 2.1, David E. Bowles, Michael H. Williams, Hope R. Dodd, Lloyd W. Morrison, Janice A. Hinsey, J. Tyler Cribbs, Gareth A. Rowell, Michael D. Debecker, Jennifer L. Haack-Gaynor, Jeffrey M. Williams Feb 2021

Protocol For Monitoring Aquatic Invertebrates Of Small Streams In The Heartland Inventory & Monitoring Network, Version 2.1, David E. Bowles, Michael H. Williams, Hope R. Dodd, Lloyd W. Morrison, Janice A. Hinsey, J. Tyler Cribbs, Gareth A. Rowell, Michael D. Debecker, Jennifer L. Haack-Gaynor, Jeffrey M. Williams

United States National Park Service: Publications

Executive Summary

The Heartland Inventory and Monitoring Network (HTLN) is a component of the National Park Service’s (NPS) strategy to improve park management through greater reliance on scientific information. The purposes of this program are to design and implement long-term ecological monitoring and provide information for park managers to evaluate the integrity of park ecosystems and better understand ecosystem processes. Concerns over declining surface water quality have led to the development of various monitoring approaches to assess stream water quality. Freshwater streams in network parks are threatened by numerous stressors, most of which originate outside park boundaries. Stream condition and …


Agate Fossil Beds National Monument, Paleontological Resources Management Plan (Public Version), Scott Kottkamp, Vincent L. Santucci, Justin S. Tweet, Jessica De Smet, Ellen Stark Sep 2020

Agate Fossil Beds National Monument, Paleontological Resources Management Plan (Public Version), Scott Kottkamp, Vincent L. Santucci, Justin S. Tweet, Jessica De Smet, Ellen Stark

United States National Park Service: Publications

Executive Summary

Since Agate Springs Ranch was founded by James H. Cook in 1887, exquisite examples of transitional Miocene mammalian fauna have been found along this stretch of the Niobrara River valley. Collectively these paleontological discoveries, along with the existing archeological and historical Native American collection, were the basis for establishing Agate Fossil Beds National Monument (AGFO) as a unit of the National Park System (NPS). The fossil remains from the Harrison and Anderson Ranch formations span a short, but important, time period within the Miocene Epoch. AGFO has provided science with an intimate look into North American mammalian evolution …


Rfia: An R Package For Estimation Of Forest Attributes With The Us Forest Inventory And Analysis Database, Hunter Stanke, Andrew O. Finley, Aaron S. Weed, Brian F. Walters, Grant M. Domke Jun 2020

Rfia: An R Package For Estimation Of Forest Attributes With The Us Forest Inventory And Analysis Database, Hunter Stanke, Andrew O. Finley, Aaron S. Weed, Brian F. Walters, Grant M. Domke

United States National Park Service: Publications

Forest Inventory and Analysis (FIA) is a US Department of Agriculture Forest Service program that aims to monitor changes in forests across the US. FIA hosts one of the largest ecological datasets in the world, though its complexity limits access for many potential users. rFIA is an R package designed to simplify the estimation of forest attributes using data collected by the FIA Program. Specifically, rFIA improves access to the spatiotemporal estimation capacity of the FIA Database via space–time indexed summaries of forest variables within user-defined population boundaries (e.g., geographic, temporal, biophysical). The package implements multiple design-based estimators, and has …


Development Of A Modified Floristic Quality Index As A Rapid Habitat Assessment Method In The Northern Everglades, Rebakah E. Gibble, Donatto D. Surratt May 2020

Development Of A Modified Floristic Quality Index As A Rapid Habitat Assessment Method In The Northern Everglades, Rebakah E. Gibble, Donatto D. Surratt

United States National Park Service: Publications

Floristic quality assessments (FQA) using floristic quality indices (FQIs) are useful tools for assessing and comparing vegetation communities and related habitat condition. However, intensive vegetation surveys requiring significant time and technical expertise are necessary, which limits the use of FQIs in environmental monitoring programs. This study modified standard FQI methods to develop a rapid assessment method for characterizing and modeling change in wetland habitat condition in the northern Everglades. Method modifications include limiting vegetation surveys to a subset of taxa selected as indicators of impact and eliminating richness and/or abundance factors from the equation. These modifications reduce the amount of …


Fire Monitoring Handbook May 2020

Fire Monitoring Handbook

United States National Park Service: Publications

Fire is a powerful and enduring force that has had, and will continue to have, a profound influence on National Park Service (NPS) lands. Fire management decisions within the National Park Service require information on fire behavior and on the effects of fire on park resources. With good reason, the public is holding park management increasingly accountable, especially in the area of fire management. Federal and state agencies are instituting progressively more stringent guidelines for burning, monitoring, and evaluation. The impetus behind these guidelines and the purpose of this handbook are to ensure that management objectives are being met, to …


Acoustically Advertising Male Harbour Seals In Southeast Alaska Do Not Make Biologically Relevant Acoustic Adjustments In The Presence Of Vessel Noise, Leanna P. Matthews, Michelle E.H. Fournet, Christine Gabriele, Holger Klinck, Susan E. Parks Mar 2020

Acoustically Advertising Male Harbour Seals In Southeast Alaska Do Not Make Biologically Relevant Acoustic Adjustments In The Presence Of Vessel Noise, Leanna P. Matthews, Michelle E.H. Fournet, Christine Gabriele, Holger Klinck, Susan E. Parks

United States National Park Service: Publications

Aquatically breeding harbour seal (Phoca vitulina) males use underwater vocalizations during the breeding season to establish underwater territories, defend territories against intruder males, and possibly to attract females. Vessel noise overlaps in frequency with these vocalizations and could negatively impact breeding success by limiting communication space. In this study, we investigated whether harbour seals employed anti-masking strategies to maintain communication in the presence of vessel noise in Glacier Bay National Park and Preserve, Alaska. Harbour seals in this location did not sufficiently adjust source levels or acoustic parameters of vocalizations to compensate for acoustic masking. Instead, for every 1 dB …


Carnivore Population Structure Across An Urbanization Gradient: A Regional Genetic Analysis Of Bobcats In Southern California, Julia G. Smith, Megan K. Jennings, Erin E. Boydston, Kevin R. Crooks, Holly B. Ernest, Seth Riley, Laurel E. K. Serleys, Shaelynn Sleater-Squires, Rebecca L. Lewison Mar 2020

Carnivore Population Structure Across An Urbanization Gradient: A Regional Genetic Analysis Of Bobcats In Southern California, Julia G. Smith, Megan K. Jennings, Erin E. Boydston, Kevin R. Crooks, Holly B. Ernest, Seth Riley, Laurel E. K. Serleys, Shaelynn Sleater-Squires, Rebecca L. Lewison

United States National Park Service: Publications

Context In human-dominated landscapes, habitat fragmentation and barriers to movement can interrupt gene flow. While often considered at a local extent, regional analyses are also needed to reveal broader landscape-mediated population processes.

Objectives To explore the relationship between patterns of gene flow and fragmentation resulting from urbanization across southern California, we used the bobcat as an indicator species. We assembled data for a landscape level genetic analysis across southern California from both archived and new samples, including two northern Californian populations for comparison, to identify local and regional areas affected by isolation.

Methods Our regional analyses focused on a dataset …


Asynchronous Carbon Sink Saturation In African And Amazonian Tropical Forests, Wannes Hubau, Simon L. Lewis, Et. Al. Authors Mar 2020

Asynchronous Carbon Sink Saturation In African And Amazonian Tropical Forests, Wannes Hubau, Simon L. Lewis, Et. Al. Authors

United States National Park Service: Publications

Structurally intact tropical forests sequestered about half of the global terrestrial carbon uptake over the 1990s and early 2000s, removing about 15 percent of 1–3 anthropogenic carbon dioxide emissions. Climate-driven vegetation models 4,5 typically predict that this tropical forest ‘carbon sink’ will continue for decades . Here we assess trends in the carbon sink using 244 structurally intact African tropical forests spanning 11 countries, compare them with 321 published plots from Amazonia and investigate the underlying drivers of the trends. The carbon sink in live aboveground biomass in intact African tropical forests has been stable for the three decades to …


Problematic Plant Monitoring In Homestead National Monument Of America, 2006–2017, Craig C. Young Mar 2020

Problematic Plant Monitoring In Homestead National Monument Of America, 2006–2017, Craig C. Young

United States National Park Service: Publications

Abstract

Managers are challenged with the impact of problematic plants, including exotic, invasive, and pest plant species. Information on the abundance, distribution, and location of these plants is essential for developing risk-based approaches to managing these species. Based on surveys conducted in 2006, 2009, 2013, and 2017, Heartland Inventory and Monitoring Network staff and contractors identified a cumulative total of 20 potentially problematic plant species in Homestead National Monument of America (NMA). Of the 13 species found in 2017, we characterized 4 as very low frequency, 4 as low frequency, 2 as medium frequency, and 3 as high frequency. Only …


Problematic Plant Monitoring In Tallgrass Prairie National Preserve, 2006–2018, Craig C. Young Mar 2020

Problematic Plant Monitoring In Tallgrass Prairie National Preserve, 2006–2018, Craig C. Young

United States National Park Service: Publications

Abstract

Managers are challenged with the impact of problematic plants, including exotic, invasive, and pest plant species. Information on the abundance, distribution, and location of these plants is essential for developing risk-based approaches to managing these species. Based on surveys conducted in 2006, 2010, 2014, and 2018, Heartland Inventory and Monitoring Network staff and contractors identified a cumulative total of 33 problematic plant species in Tallgrass Prairie National Preserve. Of the 27 species found in 2018, we characterized 14 as very low frequency, 9 as low frequency, 4 as medium frequency, and 0 as high frequency. Only 4 (14.8%) of …


Estimation Of Available Epinephrine Dose In Expired And Discolored Autoinjectors Via Quantitative Smartphone Imaging, Amirus Saleheen, Bill M. Campbell, Rebecca A. Prosser, Christopher A. Baker Feb 2020

Estimation Of Available Epinephrine Dose In Expired And Discolored Autoinjectors Via Quantitative Smartphone Imaging, Amirus Saleheen, Bill M. Campbell, Rebecca A. Prosser, Christopher A. Baker

United States National Park Service: Publications

Epinephrine autoinjectors (EAIs) are important first aid medications for treating anaphylaxis. A 10-fold price increase over the past 12 years and evidence that expired EAIs may still contain significant doses of available epinephrine have motivated interest in the efficacy of expired EAIs as treatments of last resort. Degradation of expired EAIs, which can be caused by improper storage conditions, results in various degrees of discoloration of the epinephrine solution. Previous studies have determined that significant epinephrine remains available in expired EAIs, but these have only considered EAIs that show no discoloration. Here, we investigate the potential for colorimetric estimation of …


Effects Of Culling White-Tailed Deer On Tree Regeneration And Microstegium Vimineum, An Invasive Grass, John Paul Schmit, Elizabeth R. Matthews, Andrejs Brolis Feb 2020

Effects Of Culling White-Tailed Deer On Tree Regeneration And Microstegium Vimineum, An Invasive Grass, John Paul Schmit, Elizabeth R. Matthews, Andrejs Brolis

United States National Park Service: Publications

Reduction of forest regeneration due to overbrowsing by white-tailed deer is a growing concern for land managers. Abundant deer can impede forest regeneration through direct predation on tree seedlings. Additionally high deer density can facilitate the establishment of a dense understory of browse tolerant plant species that shades seedlings and persists even in the absence of deer. In response to these challenges, land managers have sought to reduce deer herds to restore tree regeneration, but few studies have evaluated the effectiveness of this management. Our study took place in Catoctin Mountain Park, a US National Park Service unit with a …


Nurse Rock Microclimates Significantly Buffer Exposure To Freezing T Temperature And Moderate Summer Temperature, Joshua L. Conver, Elliott Yarwood, Lucas D. Hetherington, Don E. Swann Feb 2020

Nurse Rock Microclimates Significantly Buffer Exposure To Freezing T Temperature And Moderate Summer Temperature, Joshua L. Conver, Elliott Yarwood, Lucas D. Hetherington, Don E. Swann

United States National Park Service: Publications

Nurse tree canopies mitigate exposure to freezing temperatures that could result in injury or mortality to the saguaro cactus (Carnegiea gigantea). Abiotic objects have been hypothesized to provide similar beneficial microclimates. We used data loggers at 11 nurse rock sites to record daily daytime summer maximum and winter nighttime minimum temperatures at Saguaro National Park, Arizona, to examine the effectiveness of rocks to moderate seasonal temperature extremes in the microclimate. Temperatures at rock sites averaged 2 °C warmer than exposed open control sites in winter. We found that the efficiency of rocks to act as insulators significantly increased as temperature …


Beryllium-7 Elucidate Sediment Dynamics Of The Branford River Estuary, Connecticut, Usa, Gaboury Benoit, Matthew Hirschbeck, Beth Bisson Feb 2020

Beryllium-7 Elucidate Sediment Dynamics Of The Branford River Estuary, Connecticut, Usa, Gaboury Benoit, Matthew Hirschbeck, Beth Bisson

United States National Park Service: Publications

Berrylium-7 elucidates sediment dynamics (i.e., sources, sinks, deposition, and resuspension) in a Connecticut estuary. Average 7 −2−1 annual atmospheric deposition of Be is 290 mBq cm year. Sediment samples from 43 locations within the estuary show that 7Be deposition is spatially complex, but were statistically indistinguishable a year apart. Weekly time series of sediments indicate 7 that levels are nearly constant on this shorter time scale on ceradio active decay is taken into account. Be levels in sediments area balance between steady losses through radioactive decay and periodic pulse inputs following rainstorms. The water column was measured intensively during three …


Implications Of Organic Mass To Carbon Ratios Increasing Over Time In The Rural United States, W.C. Malm, B.A. Schichtel, J.L. Hand, A.J. Prenni Feb 2020

Implications Of Organic Mass To Carbon Ratios Increasing Over Time In The Rural United States, W.C. Malm, B.A. Schichtel, J.L. Hand, A.J. Prenni

United States National Park Service: Publications

The thermal evolution procedure used by most monitoring programs in the United States to determine carbonaceous aerosol concentrations is referred to as the thermal‐optical reflectance method, where an aerosol sample that has been collected on a quartz filter is heated and evolved carbon is characterized as either organic (OC) or light absorbing carbon (LAC). Evolved carbon assigned to OC is multiplied by a factor, Roc, to achieve an estimate of organic mass. Over the last 10–15 years, Roc, estimated through multiple linear regression analysis of data collected in the Interagency Monitoring of Protected Visual Environments (IMPROVE) program, has increased at …