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Full-Text Articles in Physical Sciences and Mathematics

Fauna, Flora, And Land Cover Changes Over The Last Two Decades In The Mobile-Tensaw River Delta, Gabriel De Oliveria, Steven R. Schultze, Guilherme Mataveli Jan 2024

Fauna, Flora, And Land Cover Changes Over The Last Two Decades In The Mobile-Tensaw River Delta, Gabriel De Oliveria, Steven R. Schultze, Guilherme Mataveli

Technical Reports

A technical report documenting ecosystem changes to the Mobile-Tensaw River Delta region due to urban expansion over approximately two decades (2001-2019).


Constituent Loads And Trends In The Upper Illinois River Watershed: A Nonpoint Source Management Program Priority Watershed, Erin M. Grantz, Brian E. Haggard Feb 2023

Constituent Loads And Trends In The Upper Illinois River Watershed: A Nonpoint Source Management Program Priority Watershed, Erin M. Grantz, Brian E. Haggard

Technical Reports

The Arkansas Department of Agriculture - Natural Resources Division (ANRD) has identified the Upper Illinois River Watershed (UIRW; 11110103), a hydrologic unit code (HUC) 8 watershed, located in Northwest Arkansas for prioritization by the Nonpoint Source (NPS) Management Program. URIW encompasses the Illinois River from its headwaters to the state line with Oklahoma and has been the subject of interstate disputes over water quality for decades. Nonpoint source pollution concerns in UIRW are excess nutrients from agriculture and sediment from changes in land use/land cover (LULC).

Local, state, and national groups, including the NPS Source Management Program, have invested in …


Constituent Loads And Trends In The Upper White River Basin: A Nonpoint Source Management Program Priority Watersheds, Erin M. Grantz, Brian E. Haggard Feb 2023

Constituent Loads And Trends In The Upper White River Basin: A Nonpoint Source Management Program Priority Watersheds, Erin M. Grantz, Brian E. Haggard

Technical Reports

The Arkansas Department of Agriculture – Natural Resources Division (ANRD) has identified the Upper White River Basin (UWRB; HUC 11010001) a hydrologic unit code (HUC) 8 watersheds, located in Northwest Arkansas, for prioritization by the Nonpoint Source (NPS) Management Program. UWRB includes Beaver Lake in its borders, the drinking water source for 1 in 6 Arkansans. Nonpoint source pollution concerns in these watersheds are excess nutrients from agriculture and sediment from changes in land use/land cover (LULC).

Local, state, and national groups, including the NPS Source Management Program, have invested in education, best management practices, and streambank restoration in the …


Watershed Prioritization To Reduce Nutrient Export: A Framework For The State Of Arkansas Based On Ambient Water Quality Monitoring Data, Erin Grantz, Brian E. Haggard Jul 2022

Watershed Prioritization To Reduce Nutrient Export: A Framework For The State Of Arkansas Based On Ambient Water Quality Monitoring Data, Erin Grantz, Brian E. Haggard

Technical Reports

The annual formation of the Northern Gulf of Mexico hypoxic zone is driven by nutrient loading from the Mississippi-Atchafalaya River Basin (MARB). Member States of The Mississippi River/Gulf of Mexico Hypoxia Task have developed statewide strategies to identify priorities and opportunities for nutrient export reduction in the MARB. In 2014, the State of Arkansas joined the Task Force and initiated an Arkansas Nutrient Reduction Strategy (ANRS), which currently prioritizes ten Hydrologic Unit Code 8 (HUC-8) watersheds (ANRD, 2014). These priority watersheds were not selected based on measured in-stream nutrient concentrations or trends, which impedes quantitative assessment, goal setting, and linking …


Defining Critical Or Hydrologic Conditions As Sampled During The Joint Study, Brian E. Haggard, Erin Grantz, J. T. Scott Jul 2022

Defining Critical Or Hydrologic Conditions As Sampled During The Joint Study, Brian E. Haggard, Erin Grantz, J. T. Scott

Technical Reports

The “Joint Study” was conducted to fulfill the obligations of the second “Statement of Joint Principles and Actions” agreed to by the states of Arkansas and Oklahoma. The “Joint Study” affirmed the magnitude of Oklahoma’s Scenic River total phosphorus (TP) criteria (i.e., 0.037 mg/L), but it added the new caveat of applying the criteria to “critical conditions.” The primary purpose of this paper was to define “critical conditions” based on the range in base flow proportions (BFP) of total streamflow on days that were sampled in the “Joint Study,” where BFP is base flow discharge divided by total stream flow …


Sediment Phosphorus Release At Lake Fayetteville, Summer 2020, Brian E. Haggard, Abbie L. Lasater, Morgan B. Dulin, Bradley J. Austin May 2021

Sediment Phosphorus Release At Lake Fayetteville, Summer 2020, Brian E. Haggard, Abbie L. Lasater, Morgan B. Dulin, Bradley J. Austin

Technical Reports

The purpose of this project was to evaluate the release of dissolved phosphorus (P) from bottom sediment at Lake Fayetteville, and the potential use of aluminum sulfate (Al2(SO4)3) to remediate the P stored and released by bottom sediments. Intact sediment cores (n=18) were taken at three locations, named inlet, mid and dam sites at Lake Fayetteville. The cores were incubated with 1 L of overlying water with light excluded and bubbled with air (half, aerobic treatment) and N2 (other half, anaerobic). Water samples were pulled and analyzed for soluble reactive P (SRP), and that water was replaced with filtered lake …


Water Quality Monitoring In The Upper Poteau River Watershed, Abbie Lasater, Brian E. Haggard Jan 2021

Water Quality Monitoring In The Upper Poteau River Watershed, Abbie Lasater, Brian E. Haggard

Technical Reports

The Upper Poteau River Watershed (UPRW) has been listed as a priority watershed in Arkansas since 1998 due to nutrient and sediment enrichment from point and nonpoint sources (NPS). According to the Arkansas NPS pollution management plan, the goals for the UPRW are to reduce pollutant levels that will restore all designates uses and target subwatersheds where implementation of management practices can have the greatest impact. Over the last several years, many 319(h) projects have been implemented and point sources have been reduced in order to improve water quality in the UPRW. The purpose of this study was to monitor …


Turbidity And Ion Concentrations Vary With Land Use And Underlying Geology At The West Fork Of The White River, Erin E. Scott, Brian E. Haggard Nov 2019

Turbidity And Ion Concentrations Vary With Land Use And Underlying Geology At The West Fork Of The White River, Erin E. Scott, Brian E. Haggard

Technical Reports

The West Fork of the White River (WFWR) watershed in northwest Arkansas is a trans-ecoregion watershed and is experiencing land-use changes, especially in the downstream portion of the watershed. The entire 54-km long river has been on the State’s 303(d) list of impaired waterbodies for turbidity, total dissolved solids (TDS), and sulfate for many years. The purpose of this study was to identify which part(s) of the river fail to meet applicable water quality standards (WQS) and to investigate possible sources of pollutants, whether human-caused or naturally occurring. Water samples were collected once or twice a month at 9 sites …


Stream Water Quality To Support Huc 12 Prioritization In The Lake Wister Watershed, Oklahoma: August 2017 Through May 2019, Bradley J. Austin, Brina A. Smith, Brian E. Haggard Nov 2019

Stream Water Quality To Support Huc 12 Prioritization In The Lake Wister Watershed, Oklahoma: August 2017 Through May 2019, Bradley J. Austin, Brina A. Smith, Brian E. Haggard

Technical Reports

Nonpoint source pollution associated with human land use (agriculture and urbanization) is one of the leading causes of impairment to waterways in the United States (EPA 2000). The primary pollutants associated with agricultural and urban land use are sediment and nutrients which enter nearby streams during rain events and are then carried downstream. These sediments and nutrients may result in water quality issues in the downstream water bodies like increased algal growth or decreased water clarity (e.g. Smith et al., 1999). Best management practices (BMPs) are often used to mitigate the effects of nonpoint source pollution in the watershed. Practices …


Constituent Loads And Trends In The Upper Illinois River Watershed And Upper White River Basin: 2015 October Through 2018 September, Erin E. Scott, Brian E. Haggard Feb 2019

Constituent Loads And Trends In The Upper Illinois River Watershed And Upper White River Basin: 2015 October Through 2018 September, Erin E. Scott, Brian E. Haggard

Technical Reports

The Arkansas Natural Resources Commission (ANRC) identified two priority hydrologic unit code (HUC) 8 watersheds, the Upper White River Basin (UWRB; HUC 11010001) and the Upper Illinois River Watershed (UIRW; 11110103), in northwest Arkansas. Nonpoint source (NPS) pollution is a concern in these watersheds, such as excess nutrients from agriculture and sediment from changes in land uses. Several NPS pollution projects have been funded by ANRC, including streambank restoration on Sager Creek and best management practices (BMP) to control urban sediment in Fayetteville. The purpose of this project was to collect water samples at 15 sites in the UWRB and …


Managing Lake Fertility Within The Guidelines Of A Nutrient Management Plan And Based On Algal Nutrient Limitation, Bradley J. Austin, J. Thad Scott, Brian E. Haggard Nov 2018

Managing Lake Fertility Within The Guidelines Of A Nutrient Management Plan And Based On Algal Nutrient Limitation, Bradley J. Austin, J. Thad Scott, Brian E. Haggard

Technical Reports

The specific objectives were to first, monitor nutrients, algal biomass, and water clarity in lakes Cove, Spring, and Wedington. Second, evaluate whether algal growth in each of the lakes was limited by N, P, or both N and P. This research was conducted to help USFS better manage lake fertilization to maximize algal growth and improve the fisheries within these lakes.


Watershed Investigative Support To The Poteau Valley Improvement Authority: Stream Water Quality To Support Huc 12 Prioritization In The Lake Wister Watershed, Oklahoma, Bradley J. Austin, Brina A. Smith, Brian E. Haggard Feb 2018

Watershed Investigative Support To The Poteau Valley Improvement Authority: Stream Water Quality To Support Huc 12 Prioritization In The Lake Wister Watershed, Oklahoma, Bradley J. Austin, Brina A. Smith, Brian E. Haggard

Technical Reports

Nonpoint source pollution associated with human land use (agriculture and urbanization) is one of the leading causes of impairment to waterways in the United States (EPA, 2000). The primary pollutants associated with agricultural and urban land use are sediment and nutrients which enter nearby streams during rain events and are then carried downstream. These sediments and nutrients may result in water quality issues in the downstream water bodies like increased algal growth or decreased water clarity (e.g. Smith et al., 1999).


Final Report To Governors From The Joint Study Committee And Scientific Professionals, Brian Haggard, Derek Smithee, Ryan Benefield, Shellie Chard, Marty Matlock, Shanon Phillips, Ryan King Jan 2017

Final Report To Governors From The Joint Study Committee And Scientific Professionals, Brian Haggard, Derek Smithee, Ryan Benefield, Shellie Chard, Marty Matlock, Shanon Phillips, Ryan King

Technical Reports

The intent of this publication of the Arkansas Water Resources Center is to provide a location whereby a final report on water research to a funding entity can be archived. The States of Arkansas and Oklahoma signed the Second Statement of Joint Principles and Actions in 2013 to form a governors’ appointed ‘Joint Study Committee’ to oversee the ‘Joint Study’ and make recommendations on the phosphorus criteria in Oklahoma’s Scenic Rivers. This publication has maintained the original format of the report as submitted to the Governors of Arkansas and Oklahoma.


Beaver Lake Numeric Chlorophyll-A And Secchi Transparency Standards, Phases Ii And Iii: Uncertainty And Trend Analysis, J. Thad Scott, Brian E. Haggard, Zachary Simpson, Matthew Rich Oct 2016

Beaver Lake Numeric Chlorophyll-A And Secchi Transparency Standards, Phases Ii And Iii: Uncertainty And Trend Analysis, J. Thad Scott, Brian E. Haggard, Zachary Simpson, Matthew Rich

Technical Reports

The objective of Phases II and III of this study were to 1) assess the variation in chl‐a and ST across multiple spatial and temporal scales in Beaver Lake in order to validate the assessment method, and 2) quantify trends in chl‐a, ST, and nutrient (total phosphorus and total nitrogen) concentrations in Beaver Lake and the major inflowing rivers to verify any potential water quality impairment.


Database Analysis To Support Nutrient Criteria Development (Phase Ii), B. E. Haggard, M.A. Evans-White, L.B. Massey, E.M. Grantz Oct 2016

Database Analysis To Support Nutrient Criteria Development (Phase Ii), B. E. Haggard, M.A. Evans-White, L.B. Massey, E.M. Grantz

Technical Reports

The intent of this publication of the Arkansas Water Resources Center is to provide a location whereby a final report on water research to a funding agency can be archived. The Texas Commission on Environmental Quality (TCEQ) contracted with University of Arkansas researchers for a multiple year project titled “Database Analysis to Support Nutrient Criteria Development”. This publication covers the second of three phases of that project and has maintained the original format of the report as submitted to TCEQ. This report can be cited either as an AWRC publication (see below) or directly as the final report to TCEQ.


Database Analysis To Support Nutrient Criteria Development (Phase I), B. E. Haggard, J.T. Scott, M.A. Evans-White Oct 2016

Database Analysis To Support Nutrient Criteria Development (Phase I), B. E. Haggard, J.T. Scott, M.A. Evans-White

Technical Reports

The intent of this publication of the Arkansas Water Resources Center is to provide a location whereby a final report on water research to a funding agency can be archived. The Texas Commission on Environmental Quality (TCEQ) contracted with University of Arkansas researchers for a multiple year project titled “Database Analysis to Support Nutrient Criteria Development”. This publication covers the first of three phases of that project and has maintained the original format of the report as submitted to TCEQ. This report can be cited either as an AWRC publication (see below) or directly as the final report to TCEQ.


Database Analysis To Support Nutrient Criteria Development (Phase Iii), J. T. Scott, E.M. Grantz Oct 2016

Database Analysis To Support Nutrient Criteria Development (Phase Iii), J. T. Scott, E.M. Grantz

Technical Reports

The intent of this publication of the Arkansas Water Resources Center is to provide a location whereby a final report on water research to a funding agency can be archived. The Texas Commission on Environmental Quality (TCEQ) contracted with University of Arkansas researchers for a multiple year project titled “Database Analysis to Support Nutrient Criteria Development”. This publication covers the third of three phases of that project and has maintained the original format of the report as submitted to TCEQ. This report can be cited either as an AWRC publication (see below) or directly as the final report to TCEQ.


Bella Vista Lakes Project: Fertility Management, J. Thad Scott Jun 2016

Bella Vista Lakes Project: Fertility Management, J. Thad Scott

Technical Reports

No abstract provided.


Dissolved Oxygen Monitoring In Kings River And Leatherwood Creek, Eric Cummings, Erin E. Scott, Marty Matlock, Brian E. Haggard Mar 2016

Dissolved Oxygen Monitoring In Kings River And Leatherwood Creek, Eric Cummings, Erin E. Scott, Marty Matlock, Brian E. Haggard

Technical Reports

The Clean Water Act (CWA) establishes the basic structure used to regulate water quality. Under the CWA, States are required to assess water bodies relative to water‐quality standards and designated beneficial uses and then to submit lists of impaired bodies every other year to the US Environmental Protection Agency (USEPA). In 2015, at least 4,800 water bodies were listed as impaired by dissolved oxygen across the US (USEPA, 2015). Aquatic species like fish and macroinvertebrates depend on adequate dissolved oxygen for survival. Low dissolved oxygen can lead to fish kills, reduced aquatic diversity, and nuisance smells from anaerobic conditions – …


Constituent Loads And Trends In The Upper Illinois River Watershed And Upper White River Basin, Erin E. Scott, Zach P. Simpson, Brian E. Haggard Jan 2016

Constituent Loads And Trends In The Upper Illinois River Watershed And Upper White River Basin, Erin E. Scott, Zach P. Simpson, Brian E. Haggard

Technical Reports

Water chemistry can greatly influence the quality of surface waters and affect the ability for streams and rivers to meet their designated use(s). In Arkansas, many streams and rivers were placed on the 2008 303(d) list of impaired water bodies due to excess levels of nutrients, chlorides, sulfates, and sediments (ADEQ, 2008). These constituents continue to be listed as the potential cause for water‐quality impairments through the most recent draft 303(d) list (ADEQ, 2014). The Arkansas Non‐Point Source (NPS) Management Program wants to reduce poll‐ utant loading from the landscape and improve water quality, where funding for projects is targeted …


Simulated Use Of 'First-Order' Ponds To Reduce Peakflow In An Eroding River System, J. Thad Scott, Brian E. Haggard Oct 2015

Simulated Use Of 'First-Order' Ponds To Reduce Peakflow In An Eroding River System, J. Thad Scott, Brian E. Haggard

Technical Reports

No abstract provided.


Bacteria Monitoring In The Upper Illinois River Watershed, Erin E. Scott, Brina A. Smith, Mansoor Leh, Blake Arnold, Brian E. Haggard Sep 2015

Bacteria Monitoring In The Upper Illinois River Watershed, Erin E. Scott, Brina A. Smith, Mansoor Leh, Blake Arnold, Brian E. Haggard

Technical Reports

This project focuses on the Upper Illinois River Watershed (UIRW; HUC 11110103), which is within the Boston Mountains and Ozark Highlands ecoregions in northwest Arkansas. Headwaters of the Illinois River originate near Hogeye, Arkansas and flow north through Savoy, then west into Oklahoma near Watts. The UIRW drains an area of 1952 km2 , of which 50.3% is pasture and grassland, 35.9% is forest, 8.8% is urban and suburban, 4.3% is transitional and 0.3% is water (Arkansaswater.org, 2015). Land use throughout the watershed is also changing, with increases in residential, commercial and industrial development. The IRW has been designated a …


Monitoring Water Resources Of The Gulf Mountain Wildlife Management Area To Evaluate Possible Effects Of Natural Gas Development, Bradley J. Austin, Erin E. Scott, Sally Entrekin, Michelle A. Evans-White, Brian E. Haggard Jul 2015

Monitoring Water Resources Of The Gulf Mountain Wildlife Management Area To Evaluate Possible Effects Of Natural Gas Development, Bradley J. Austin, Erin E. Scott, Sally Entrekin, Michelle A. Evans-White, Brian E. Haggard

Technical Reports

No abstract provided.


Constituent Load Estimation In The Lower Ouachita-Smackover Watershed, Zach P. Simpson, Erin E. Scott, Brian E. Haggard May 2015

Constituent Load Estimation In The Lower Ouachita-Smackover Watershed, Zach P. Simpson, Erin E. Scott, Brian E. Haggard

Technical Reports

Water quality was monitored at 21 sites in the Lower Ouachita‐Smackover Watershed from 2013 November through 2014 September. The U.S. Geological Survey maintains discharge monitoring stations at two of these sites, Moro Creek (USGS 07362500) and Smackover Creek (USGS 07362100), which were sampled during base flow and storm event conditions, whereas the other sites were only sampled during baseflow. The Arkansas Water Resources Center (AWRC) estimated constituent loads for nitrate‐N (NO₃‐–N), total nitrogen (TN), soluble reactive phosphorus (SRP), total phosphorus (TP) and total suspended solids (TSS) using the U.S. Geological Survey LOADEST software. LOADEST creates regression models between constituent concentrations …


Evaluating The Assessment Methodology For The Chlorophyll-A And Secchi Transparency Criteria At Beaver Lake, Arkansas, J. Thad Scott, Brian E. Haggard Jan 2015

Evaluating The Assessment Methodology For The Chlorophyll-A And Secchi Transparency Criteria At Beaver Lake, Arkansas, J. Thad Scott, Brian E. Haggard

Technical Reports

No abstract provided.


Relation Of Chlorine Demand To The Water Quality Of Beaver Lake, Erin E. Scott, Jaime M. Gile, Brian E. Haggard Dec 2014

Relation Of Chlorine Demand To The Water Quality Of Beaver Lake, Erin E. Scott, Jaime M. Gile, Brian E. Haggard

Technical Reports

No abstract provided.


Pecci Code (Python Estimation For Carbon Concentration And Isotopes) For Calculating The Concentration And Stable Carbon Isotopic Composition Of Dissolved Inorganic Carbon (Dic) In Precipitation For Northwestern Arkansas, Katherine J. Knierim, Phillip D. Hays Dec 2014

Pecci Code (Python Estimation For Carbon Concentration And Isotopes) For Calculating The Concentration And Stable Carbon Isotopic Composition Of Dissolved Inorganic Carbon (Dic) In Precipitation For Northwestern Arkansas, Katherine J. Knierim, Phillip D. Hays

Technical Reports

In karst settings, hydrograph separations using isotopic tracers are commonly and effectively used to quantify the proportions of rain rapidly delivered to springs along fractures and conduits during storm events. Dissolved inorganic carbon (DIC) is an effective, non‐conservative tracer for use in hydrograph separations of karst waters because of the ubiquitous nature of carbon in the sources of waters to caves and springs and unique concentrations and isotopic compositions of carbon inputs. DIC concentration and isotopic composition (δ¹³C‐DIC) in rain are typically calculated based on atmospheric carbon dioxide (CO₂) using equilibrium carbonate reactions and stable carbon isotope fractionation values. As …


Water Quality Monitoring For Selected Priority Watersheds In Arkansas, Upper Saline, Poteau And Strawberry Rivers, L. B. Massey, J.A. Mccarty, M.D. Matlock, A.N. Sharpley, B.E. Haggard Dec 2013

Water Quality Monitoring For Selected Priority Watersheds In Arkansas, Upper Saline, Poteau And Strawberry Rivers, L. B. Massey, J.A. Mccarty, M.D. Matlock, A.N. Sharpley, B.E. Haggard

Technical Reports

Arkansas Natural Resources Commission has identified three priority hydrological unit code (HUC) 8 watersheds, the Upper Saline (HUC 08040203), Poteau (HUC 11110105), and Strawberry Watersheds (HUC 11010012). SWAT models have been developed to estimate nutrient and sediment loads in these watersheds where limited water‐quality data was available. The purpose of this project was to collect additional water samples across these HUC 8 watersheds to better understand how water quality changes across subwatershed with differing land use mixes, as well as estimate nitrate‐nitrogen (NO3‐N), total phosphorus (TP), and total suspended sediment (TSS) loads. Water samples were collected at twenty sites near …


Ecological Design In The Ozarks - Workshop And Lake Frances Charrette, Steven D. Patterson, Brian E. Haggard, Mark E. Boyer May 2013

Ecological Design In The Ozarks - Workshop And Lake Frances Charrette, Steven D. Patterson, Brian E. Haggard, Mark E. Boyer

Technical Reports

No abstract provided.


Sestonic Chlorophyll-A And Nutrient Relationships Across The Red River Basin, Usa, Brian E. Haggard, J. Thad Scott, Scott D. Longing, John T. Metrailer Jan 2012

Sestonic Chlorophyll-A And Nutrient Relationships Across The Red River Basin, Usa, Brian E. Haggard, J. Thad Scott, Scott D. Longing, John T. Metrailer

Technical Reports

The Red River is a trans‐boundary, multi‐jurisdictional basin, where water‐quality standards often change at the state lines. The state agencies with USEPA Region VI focused resources to organize water‐quality data from within this basin and have it statistically analyzed to evaluate the relationships between nutrients and sestonic chlorophyll‐a (chl‐a). There were 152 sites within the Red River Basin that had nutrient and sestonic chl‐a data, and these sites were narrowed down to 132 when a minimum number of observations was required. Sestonic chl‐a levels increased with increasing nutrient concentrations; these significant regressions were used to predict nutrient concentrations at 10 …