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Full-Text Articles in Environmental Indicators and Impact Assessment

An Integrated Data-Driven Framework For Arctic Shipping: Analyzing Vessel Speed, Environmental And Ecological Factors Through Innovative Statistical Spatio-Temporal Methods, Inverse Optimization And Machine Learning, Mauli Pant Jan 2026

An Integrated Data-Driven Framework For Arctic Shipping: Analyzing Vessel Speed, Environmental And Ecological Factors Through Innovative Statistical Spatio-Temporal Methods, Inverse Optimization And Machine Learning, Mauli Pant

Theses and Dissertations

This dissertation develops an integrated data-driven framework to analyze vessel navigation and ecological risk in the United States Arctic from 2010 to 2019. As environmental change and maritime activity increase in the region, understanding how vessels respond to dynamic conditions and how those responses interact with marine ecosystems has become increasingly important. A central theme of this dissertation is the treatment of vessel speed as both an observed outcome and a decision variable reflecting trade- offs among operational, environmental, and ecological factors. The first chapter develops a predictive framework for vessel speed over ground (SOG) using Gaussian Process Boosting (GPBoost), …


Understanding The Influence Of Traffic And Noise On The Wildlife Community Surrounding Fm106 And Sh100 In South Texas, Anna Rose Mehner Dec 2024

Understanding The Influence Of Traffic And Noise On The Wildlife Community Surrounding Fm106 And Sh100 In South Texas, Anna Rose Mehner

Theses and Dissertations

In South Texas, highways create landscape fragmentation, habitat degradation, and result in wildlife vehicle collisions. Vehicle collisions are the highest known cause of mortality of the endangered ocelot (Leopardus pardalis), which led Texas Department of Transportation to install nine wildlife crossing structures (WCS) on Farm-to-Market 106 and five on State Highway 100. These highways are along Laguna Atascosa National Wildlife Refuge, which is the location of the southernmost breeding population of ocelots in the United States. Many other wildlife species including bobcat (Lynx rufus) and coyote (Canis latrans), are present along these highways and …


Structure Modifications And Alternative Monitoring Designs Of Wildlife Road Mitigation Structures, Madison T. Nadler Dec 2024

Structure Modifications And Alternative Monitoring Designs Of Wildlife Road Mitigation Structures, Madison T. Nadler

Theses and Dissertations

Wildlife mitigation structures are designed to keep animals off roadways while providing them safe passage to the other side and not impeding traffic flow. Camera traps are commonly used to assess the success of these mitigation structures, but there are downfalls to both the methods and structures. Alternative mitigation structure designs are needed to better prevent wildlife from accessing roadways in areas where they should be deterred. Additionally, traditional camera trapping methods do not accurately capture the full wildlife communities that may be utilizing these structures and other survey methods are needed, specifically aimed at small mammals, amphibians, and reptiles. …


Guiding Wildlife: Evaluating Wildlife Exit Designs And Sensor Lights For Safer Highways In South Texas, Rupesh Maharjan Dec 2024

Guiding Wildlife: Evaluating Wildlife Exit Designs And Sensor Lights For Safer Highways In South Texas, Rupesh Maharjan

Theses and Dissertations

Roadside exclusionary fencing is more prevalent on highways to prevent wildlife-vehicle collisions. Although it can mitigate wildlife road mortality by limiting their access to the road, it can also create a barrier for wildlife stranded within the right-of-way. In State Highway 100 of Texas, the Texas Department of Transportation installed ten wildlife exits to allow wildlife to escape the fenced roadway, and a pair of sensor lights on 13 wildlife guards (WGs) to scare off target species (bobcats and coyotes) from crossing the guards and accessing the roadway. In this study, the effectiveness of three wildlife exit (WE) designs were …


Mapping Urban Tree Canopy Using Publicly Available Satellite Data, Rosemary Mcguinness Aug 2024

Mapping Urban Tree Canopy Using Publicly Available Satellite Data, Rosemary Mcguinness

Theses and Dissertations

This project addresses the need for accessible, cost-effective tools for quantifying spatial and temporal changes in tree canopy cover in urban areas. Urban tree canopy provides a wide range of ecosystem services, including lowering air temperatures, reducing pollution, and mitigating stormwater runoff. Cities around the world have placed the expansion of their urban forests at the center of their sustainability goals. Consistent and timely data on urban tree canopy is essential for urban greening initiatives to succeed. Existing methods of accessing information about urban tree canopy are highly technical, costly, and labor-intensive, while the freely available source of tree canopy …


Optimizing Edge-Of-Field Water Quality Monitoring Methods To Determine The Effects Of Best Management Practices On Nutrient And Sediment Runoff, Mark Hill Aug 2023

Optimizing Edge-Of-Field Water Quality Monitoring Methods To Determine The Effects Of Best Management Practices On Nutrient And Sediment Runoff, Mark Hill

Theses and Dissertations

This study investigates the impact on water quality of combined agricultural best management practices cover crop and minimum tillage, alongside an examination of techniques used to collect those samples. Edge-of-field (EOF) water quality samples were collected from 11 working farms during a two-year paired field experiment. Results showed significant reductions in nutrient concentrations, increased discharge, and mixed findings regarding nutrient mass transport post-treatment. A suite of EOF collection techniques were compared using in-situ automated water sampling systems sampling the same runoff events. Sampling protocols influenced nutrient concentrations in composite samples, but unexpected variance in velocity sensors affected measured discharge, making …


Trace Metal Analysis Of Pond Sediments To Measure Deposition From A Coal-Fired Power Plant In Ackerman Mississippi, Charles Bills Aug 2023

Trace Metal Analysis Of Pond Sediments To Measure Deposition From A Coal-Fired Power Plant In Ackerman Mississippi, Charles Bills

Theses and Dissertations

Trace element sediment pollution due to coal power plants have been reported in many countries. In this study, pond sediment samples collected from locations around a coal fired power plant in Ackerman, MS, were evaluated for their trace element concentration and pollution status. The samples were collected at two depths to study changes in element accumulation over time. The samples were digested and the elements, As, Cd, Cr, Cu, Pb, Hg, and Zn were analyzed using ICP-MS. Results were then compared to known background concentrations as well as sediment quality guidelines and pollution thresholds. The sample locations downwind of the …


Use Of Consumer Grade Small Unmanned Aerial Systems (Suas) For Mapping Storm Damage In Forested Environments, James Dewey Cox May 2022

Use Of Consumer Grade Small Unmanned Aerial Systems (Suas) For Mapping Storm Damage In Forested Environments, James Dewey Cox

Theses and Dissertations

Storm damages to forested environments pose significant challenges to landowners, land managers, and conservationists alike. Damage scope and scale assessments can be difficult, costly, and time consuming with conventional pedestrian survey techniques. Consumer grade sUAS technology offers an efficient, cost-effective way to accurately assess storm damage in small to moderate sized survey areas (less than 10 km²). Data were collected over a 0.195 km² area of damaged timber within the Kisatchie National Forest in Central Louisiana using a DJI Mavic 2 Pro drone. Collected imagery was processed into an orthomosaic using Agisoft Metashape Professional with a resulting ground sampling distance …


Persistence And Mitigation Of Pfas Within Concrete Stormwater Drainage Infrastructure, Jason R. Mcdonald Mar 2022

Persistence And Mitigation Of Pfas Within Concrete Stormwater Drainage Infrastructure, Jason R. Mcdonald

Theses and Dissertations

The persistence, fate, and transport of per- and poly-fluoroalkyl substances, which have been shown to have adverse effects on human health, have been previously studied in environmental media such as soils and groundwater. This study investigates concrete, a medium that is rarely studied but frequently present in instances where PFAS originating from AFFF releases and spills have occurred. Used heavily throughout aviation firefighting, AFFF poses environmental hazards due to the length of PFAS degradation and toxicological implications, thus its classification as a forever chemical. From the very limited reports to date, studies have suggested very slow release from concrete, potentially …


Comparing Coastal Storm Impact To Decadal Change In Barrier Island Ecosystems, Philip A. Tuley Jan 2020

Comparing Coastal Storm Impact To Decadal Change In Barrier Island Ecosystems, Philip A. Tuley

Theses and Dissertations

Highly dynamic coastal systems respond to disturbance events with a combination of topographic and vegetative changes. Sea level rise impacts on barrier islands have been quantified, but storm effects on vegetation are limited. Here we quantified barrier island vegetation change in response to an isolated storm event and compared to long-term periods. We hypothesized that disturbance-resisting areas with high woody vegetation cover and/or high foredune elevation would experience minimal transitions after a storm event, whereas disturbance-reinforcing areas with low vegetation cover and low foredune elevation would experience greater transitions between ecosystem states after a storm event. Patterns of dissonance were …


An Analysis Of Built Environment Factors In Residences And The Associated Effects On Mental Health Symptoms Of United States Veterans, Cody J. Beemer Mar 2019

An Analysis Of Built Environment Factors In Residences And The Associated Effects On Mental Health Symptoms Of United States Veterans, Cody J. Beemer

Theses and Dissertations

Current awareness and statistics regarding negative mental health outcomes of United States Military and Veteran populations justify research into causes and methods to assist those afflicted. Growing academic research indicates connections between the built environment and the mental health of its occupants may be important. This research is intended to explore this relationship with a Veteran study group. Through the completion of a literature review, key built environment factors associated with various mental health conditions were identified. Mechanisms and pathways through which these factors can affect mental health conditions were explored. An analysis of residential built environment factors and Veteran …


Toxicological Life Cycle Impact Analysis Of Short And Long Chain Perfluorinated Compounds Compared To Impacts Of Treatment Techniques, Joshua R. Glass Mar 2019

Toxicological Life Cycle Impact Analysis Of Short And Long Chain Perfluorinated Compounds Compared To Impacts Of Treatment Techniques, Joshua R. Glass

Theses and Dissertations

Polyfluoroalkyl substances (PFAS) are man-made substances that are used as surfactants in industrial processes and commercial products most notably for the Air Force in aqueous film-forming foam. These compounds were introduced in the 1950s and have since become pervasive throughout industrial and consumer products such as carpet, leather, and paper as well as textiles that repel water, grease, and oils. As the presence of PFAS continues to grow, so do concerns for the toxicological impacts of exposure to these chemicals. Although there is much research into the toxicological impacts of PFAS, there are no regulatory treatment levels within the United …


Non-Intrusive Occupancy Detection Methods And Models, James C. Tyhurst Mar 2019

Non-Intrusive Occupancy Detection Methods And Models, James C. Tyhurst

Theses and Dissertations

Occupants in the built environment impact facility energy consumption and indoor air quality. Predicting the presence of occupants within the built environment can therefore be used to manage these factors while providing additional benefits in terms of emergency management and future space utilization. Detecting occupancy requires a combination of sensors and models to accurate assess data collected within facilities to predict occupancy. This thesis investigated occupancy detection through a non-invasive data collection sensors and model. Specifically, this thesis sought to answer two research questions examining the ability of a radial basis function to accurately predict occupancy when generated from data …


Future Melting Away: Water Stress As A Threat To Human Security In Bangladesh And The Role Of International Community, Farzana Afroz Chowdhury Jul 2018

Future Melting Away: Water Stress As A Threat To Human Security In Bangladesh And The Role Of International Community, Farzana Afroz Chowdhury

Theses and Dissertations

Bangladesh is considered as one of the frontline states in the global climate change; its policy agendas attempt to respond to the perceived security threats emanating from such changes. Water stress is one of the key problems the country is facing. Yet, links between glaciers in the Hindu Kush Himalaya, Bangladesh’s climate, growing water stress, and its implications for human security have seldom been studied. Drawing on the concepts of climate change, human security and water stress, the thesis examines the causes of Bangladesh’s freshwater crisis and its contribution to the human insecurity. Here in this study, the influence of …


Quantifying Permafrost Extent, Condition, And Degradation Rates At Department Of Defense Installations In The Arctic, Christopher A. J. Edlund Mar 2018

Quantifying Permafrost Extent, Condition, And Degradation Rates At Department Of Defense Installations In The Arctic, Christopher A. J. Edlund

Theses and Dissertations

The DoD is planning over $500M in military construction on Eielson Air Force Base (AFB) within the next three years. This construction program will expand the footprint of facilities and change parts of the storm water management scheme, which may have second order effects on the underlying permafrost layer. These changes in permafrost will drive engineering decision making at local and regional levels, and help shape the overall strategy for military readiness in the Arctic. Little site-specific knowledge exists on the human caused effects to permafrost at this location. In 2016, the permafrost degradation rates at Eielson AFB were modeled …


Experimental Evaluation Of Uranyl Transport Into Mesoporous Silica Gel Using Fluorescence, Brandon M. Dodd Jan 2018

Experimental Evaluation Of Uranyl Transport Into Mesoporous Silica Gel Using Fluorescence, Brandon M. Dodd

Theses and Dissertations

This research investigated parameters that can affect the use of nanoporous silica gel as a media for accumulating a detectable amount of uranium. The unique fluorescence of the Uranyl (UO22+) ion was used to evaluate the transport kinetics and accumulation within silica gel in a static fluid and under pressure driven flow. The addition of fluid flow decreased the time constant from on the order of an hour to approximately 2s with a very low fluid velocity of 0.36cm/s. The 0.36cm/s fluid velocity was found to be the critical velocity above which there was no gain in …


Effects Of Grazers And Elevated Temperature On The Dynamics Of A Wastewater Algal Treatment System, Mengyuan Li Jan 2017

Effects Of Grazers And Elevated Temperature On The Dynamics Of A Wastewater Algal Treatment System, Mengyuan Li

Theses and Dissertations

Wastewater algal treatment systems (ATS) have been shown to effectively remove excessive nutrients from wastewater and prevent eutrophication. However, the performance of ATS could be strongly affected by environmental factors. This study examined (1) the effect of grazers on nutrient removal rates and (2) the effect of 1.7 °C increase in temperature on algal biomass. The effect of grazers was assessed outdoors by analyzing dissolved and tissue nutrient concentrations in ATS with and without biological pesticide in two 20-day trials. The effect of elevated temperature was evaluated indoors by comparing algal biomass between heated and non-heated ATS for 20 days. …


Transportation And Sanitation Drivers Of Land Use/Land Cover Change: Loss Of The Jamaica Bay Wetlands, Margaret Joy Cytryn Aug 2015

Transportation And Sanitation Drivers Of Land Use/Land Cover Change: Loss Of The Jamaica Bay Wetlands, Margaret Joy Cytryn

Theses and Dissertations

This thesis presents an analysis (1830-2014) of the historical events of land use/land cover change in the Jamaica Bay estuary, identification of the agents of change, and a perspective on the potential drivers of transportation and sanitation in land use/land cover change.


Long-Term Effects Of Land Cover Change On Fish Assemblage Structure In The Piedmont And Coastal Plain Regions Of Virginia, Samuel F. Stickley Jan 2015

Long-Term Effects Of Land Cover Change On Fish Assemblage Structure In The Piedmont And Coastal Plain Regions Of Virginia, Samuel F. Stickley

Theses and Dissertations

Changes in land cover and fish assemblage structure were assessed across two spatial and temporal scales in the Piedmont and Coastal Plain regions of the Chesapeake Bay watershed in Virginia. A long-term, local study (1953 to 2014) on the Tuckahoe Creek watershed used digitized aerial photography and satellite images (Landsat 5 TM and Landsat 8 OLI/TIRS) to quantify land cover change for five nested catchments in 1953, 1990, and 2014. Instream fish collections from 1958, 1990, and 2014 were utilized to assess a variety of fish assemblage metrics for each of the five catchments, and analyses were performed to assess …


Characterizing Wetland Hydrology, Chemistry, And Soils For An Endemic Crayfish, The Piedmont Blue Burrower, Jess H. Gilmer Ii Jan 2014

Characterizing Wetland Hydrology, Chemistry, And Soils For An Endemic Crayfish, The Piedmont Blue Burrower, Jess H. Gilmer Ii

Theses and Dissertations

Anthropogenic alteration of Earth's ecosystems has pushed global biodiversity into a state of crisis. Freshwater species have been particularly vulnerable, with crayfish ranking as the second most imperiled taxonomic group in North America. Primary burrowers represent only 15% of crayfish species in North America; however, they constitute 32% of imperiled crayfish. Despite their conservation importance, little is known about the ecology of burrowing crayfish. To advance our knowledge about the habitat characteristics of burrowing crayfish, groundwater hydrology, water chemistry, and soil properties were assessed to determine their importance for the state-listed endangered, primary burrower Cambarns harti. Groundwater hydrology and …


"Mining" For A Reference Condition In Southern West Virginia Streams, Matthew Rouch Jan 2014

"Mining" For A Reference Condition In Southern West Virginia Streams, Matthew Rouch

Theses and Dissertations

Quarterly samples were used to estimate assemblage-level (all species combined) fish production within three minimally-impacted, southern West Virginia streams. The total annual fish production estimate was highest in Slaunch Fork (37.52 kg∙ha-1∙y-1), a tributary of the Tug Fork River, and lowest in Cabin Creek (10.59 kg∙ha-1∙y-1), a Guyandotte River tributary. Creek Chub Semotilus atromaculatus, Mottled Sculpin Cottus bairdii and Blacknose Dace Rhinicthys atratulus were the most abundant species among sites, accounting for >90% of all sampled individuals. Reference condition criteria were also selected and metrics calculated for each of the three …


Modeling The Impact Of Cracking In Low Permeability Layers In A Groundwater Contamination Source Zone On Dissolved Contamination Source Zone On Dissolved Contaminant Fate And Transport, Katherine W. Sievers Mar 2012

Modeling The Impact Of Cracking In Low Permeability Layers In A Groundwater Contamination Source Zone On Dissolved Contamination Source Zone On Dissolved Contaminant Fate And Transport, Katherine W. Sievers

Theses and Dissertations

The storage and transport of a dense non-aqueous phase liquid (DNAPL) was evaluated using a numerical model. Many DNAPLs are used as solvents by the DoD and industry. The improper disposal and handling of these chemicals has led to long term contamination of groundwater. When spilled, a DNAPL will pool atop low permeability layers and slowly dissolve creating a contaminant plume. The dissolved contaminant within a low permeability layer serves as long-term sources of contamination once the source is removed. In this study, cracks are hypothesized to exist in the low permeability layers, allowing for enhanced transport. A numerical model …


Assessing The Economic And Environmental Impacts Associated With Current Street Lighting Technologies, Carlos J. Colon Jr. Mar 2010

Assessing The Economic And Environmental Impacts Associated With Current Street Lighting Technologies, Carlos J. Colon Jr.

Theses and Dissertations

Rising global energy demand and natural disasters continuously threaten energy supplies and prices. As a result, the U.S. government has mandated all government agencies to reduce energy consumption in order to minimize dependence on foreign energy supply and reduce costs. Concern over carbon emissions and environmental impacts has also been expressed in these mandates. One solution may be to invest in newer lighting technologies, such as light-emitting diode (LED) and electrodeless induction, in order to reduce the energy consumption, environmental impact, and costs required for both exterior roadway and parking lot lighting applications. This research compared these lighting technologies with …


Analysis Of Expedient Field Decontamination Methods For The Xmx/2l-Mil High-Volume Aerosol Sampler, Brandon C. Laroche Dec 2009

Analysis Of Expedient Field Decontamination Methods For The Xmx/2l-Mil High-Volume Aerosol Sampler, Brandon C. Laroche

Theses and Dissertations

The XMX/2L-MIL is a high volume air sampler used by the Air Force Bioenvironmental Engineering community to collect biological aerosols. Without a verified decontamination technique, however, the XMX cannot be used effectively. The objective of this study was to evaluate several proposed methods for expedient field decontamination of the XMX. This study centered on the inactivation of Bacillus atrophaeus spores and vegetative Erwinia herbicola organisms from the XMX inner canister. The goals in this investigation were twofold: 1) to verify the antimicrobial efficacy of a 10% bleach solution and 2) to determine if wiping the components with a bleach-soaked paper …


The Economic Impact Of A Radiological Dispersal Device (Rde), Michael T. Lebrun Mar 2009

The Economic Impact Of A Radiological Dispersal Device (Rde), Michael T. Lebrun

Theses and Dissertations

While it will not cause the devastation of a nuclear weapon, the radiological dispersal event (RDE) is particularly dangerous in that it has the potential to cause major economic disruptions. The purpose of this research was to develop a generalized methodology that can be used to assess economic impacts, resulting from a (RDE), occurring in any location and across any industry. Currently, there is no universal approach for measuring the costs or economic impacts on businesses, or a common framework for conducting an economic impact for a RDE. The objective of this research was to aid in the RDE response …


Modeling Of Aircraft Deicing Fluid Induced Biochemical Oxygen Demand In Subsurface-Flow Constructed Treatment Wetlands, William J. Mclaughlin Mar 2009

Modeling Of Aircraft Deicing Fluid Induced Biochemical Oxygen Demand In Subsurface-Flow Constructed Treatment Wetlands, William J. Mclaughlin

Theses and Dissertations

Aircraft deicing is vital to safe operation in cold weather environments. Unfortunately, release of glycol-based aircraft deicing fluids (ADF) to waterways adjacent to airfields poses a significant environmental threat. The deicing fluids used at DoD airfields impart a high biochemical oxygen demand (BOD) when they enter waterways. The currently accepted conventional treatment is collection and transport of ADF-laden storm water to a publicly owned treatment works. The volume and BOD concentrations in the storm water often make this type of treatment impractical. Subsurface flow constructed treatment wetlands have been demonstrated to be effective in attenuating ADF-induced BOD. The models currently …


Tolerance And Accumulation Of Copper, Lead And Zinc By Ceratopteris Richardii, Dorothy Jelagat Cheruiyot Dec 2008

Tolerance And Accumulation Of Copper, Lead And Zinc By Ceratopteris Richardii, Dorothy Jelagat Cheruiyot

Theses and Dissertations

Environmental contamination has increased rapidly in recent years. There is a need to develop cheap and environmentally friendly remediation methods. Numerous studies have evaluated the ability plants to remove contaminants from the environment. The present study evaluated the ability of Ceratopteris richardii gametophytes and sporophytes to tolerate copper, lead and zinc and for the sporophytes to accumulate the three metals in their shoots. Spores were sown in plant medium treated with varying concentrations of Cu, Pb and Zn. Fifteen-day- old sporophytes were transferred into medium mixed with varying concentrations of the three metals. Ceratopteris richardii tolerated and accumulated each of …


Effect Of A Water Treatment Bmp On Nutrient Spiraling And Leaf Litter Breakdown In An Urban Stream, Megan Leclair Wheeler Oct 2008

Effect Of A Water Treatment Bmp On Nutrient Spiraling And Leaf Litter Breakdown In An Urban Stream, Megan Leclair Wheeler

Theses and Dissertations

Alterations to stream conditions caused by urbanization can compromise valuable ecosystem services, such as nutrient attenuation and carbon processing. A best management practice (BMP) water facility was installed to restore an impaired urban stream in Columbus, GA. This study was conducted to determine the effect of this BMP on nutrient spiraling and leaf litter decomposition in a 2 km stretch of Weracoba Creek. I hypothesized the BMP would (1) reduce leaf mass loss over time and (2) interfere with nutrient concentrations and uptake lengths. I characterized leaf litter decomposition using tulip tree leaves {Liriodendron tulipifera) in 1mm mesh bags deployed …


Stratification Of Southern Georgia Streams For Rapid Bioassessment Focusing On Differences In Structure And Function Of Black Water And Clear Water Streams, Salini Pradeep Pillai Feb 2007

Stratification Of Southern Georgia Streams For Rapid Bioassessment Focusing On Differences In Structure And Function Of Black Water And Clear Water Streams, Salini Pradeep Pillai

Theses and Dissertations

As part of a rapid bioassessment project for the state of Georgia, relatively unimpaired reference streams and impaired sites were sampled for biological, chemical and physical parameters, and macroinvertebrates were identified. The metrics, biological, physical and chemical metrics, were selected using Ecological Data Application System Version 3.3.2k (EDAS). Discrimination efficiency and correlations were performed to determine the best metrics that separated impaired streams from reference streams and later on to form the index of stream water quality. Principal components analysis of the selected metrics showed that some of the blackwater reference streams and clearwater reference streams are randomly placed over …


The Effects Of Nutrient Concentrations On Macroinvertebrate Distributions In Georgia, Paula Michele Pollock Brossett Apr 2005

The Effects Of Nutrient Concentrations On Macroinvertebrate Distributions In Georgia, Paula Michele Pollock Brossett

Theses and Dissertations

Nutrients are considered the second largest nonpoint source pollutant in Georgia's running water ecosystems. Nutrients can naturally occur in low amounts and are typically increased in streams as a result of industry, agriculture, silviculture, and urbanization. In large amounts, nutrients can cause many problems to occur in the stream ecosystem. Macroinvertebrates have been established as good indicators for determining the level of impairment of a stream; however, not much research has been done on how nutrients affect macroinvertebrates in a stream. Approximately 225 reference and impaired streams were sampled over a 3 - year field season, (index period from September …