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Water Utility Services: Understanding The Tension Between Viability And Affordability, Daniel Van Abs Dec 2021

Water Utility Services: Understanding The Tension Between Viability And Affordability, Daniel Van Abs

Sustainability Seminar Series

Nationally, the cost of drinking water and sewer utility services has been increasing faster than the consumer price index (inflation) since 1980, propelled by more stringent environmental standards, service area expansion, and repairs for aging infrastructure. These pressures are not abating, and in many ways are increasing. The result is that utilities need more revenue, but an increasing number of households face utility costs that are unaffordable. Shutting off these customers is counterproductive for those low-income households (somewhat like a debtors prison, where you suffer for an inability to pay), society at large, and even the utilities (which face public …


Mitigation Of Impacts To Historic Features At The Butte Reduction Works (Brw) Smelter Area Mine Waste Remediation And Contaminated Groundwater Hydraulic Control Site, Mitzi Rossillon Dec 2021

Mitigation Of Impacts To Historic Features At The Butte Reduction Works (Brw) Smelter Area Mine Waste Remediation And Contaminated Groundwater Hydraulic Control Site, Mitzi Rossillon

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Irrigation Systems Management, Dean E. Eisenhauer, Derrel L. Martin, Derek M. Heeren, Glenn J. Hoffman Dec 2021

Irrigation Systems Management, Dean E. Eisenhauer, Derrel L. Martin, Derek M. Heeren, Glenn J. Hoffman

Open Educational Resources: Textbooks

Like most textbooks, this book grew out of our desire to have written material that matches the educational needs of both the students and the instructor of a college course, in this case a course entitled Irrigation Systems Management. The book is the culmination of course notes which have been in development and use for nearly 30 years.

The emphasis of this book is on the management of irrigation systems that are used for agricultural crop production. There are two distinct components of the book, starting with the soil-water-plant-atmosphere system and how soil water should be managed to achieve the …


The Fierce Green Fire: Vol. 12 Issue 8, Wofford College. Department Of Environmental Studies Dec 2021

The Fierce Green Fire: Vol. 12 Issue 8, Wofford College. Department Of Environmental Studies

The Fierce Green Fire

No abstract provided.


Soil Microbial Community Dynamics In Response To Prescribed Extreme Fires Following Juniperus Virginiana Invasion In The Loess Canyons Of Nebraska, Julie A. Fowler Dec 2021

Soil Microbial Community Dynamics In Response To Prescribed Extreme Fires Following Juniperus Virginiana Invasion In The Loess Canyons Of Nebraska, Julie A. Fowler

School of Natural Resources: Dissertations, Theses, and Student Research

In Nebraska and other regions of the Great Plains, the conifer Juniperus virginiana (eastern redcedar) is converting grasslands to dense woodlands. This is driven by the interacting drivers of fire suppression, altered grazing regimes, climate change and other anthropogenic factors, impacting the provisioning of ecosystem services. This vegetation state transition modifies water resource regulation and biogeochemical cycles leading to altered edaphic properties including soil microbial community composition. To restore these grasslands and control J. virginiana spread, prescribed extreme burns are implemented as a management tool through local prescribed burn associations. We hypothesized that the alternative state transition to dense J. …


Developing A Practice In Remote Sensing For Next-Generation Human Rights Researchers, Theresa Harris, Jonathan Drake, Umesh K. Haritashya, Wumi Asubiaro Dada, Fredy Cumes Dec 2021

Developing A Practice In Remote Sensing For Next-Generation Human Rights Researchers, Theresa Harris, Jonathan Drake, Umesh K. Haritashya, Wumi Asubiaro Dada, Fredy Cumes

Biennial Conference: The Social Practice of Human Rights

Remote sensing is increasingly recognized as an important tool for documenting human rights abuses. When used alongside interviews, case studies, surveys, forensic science, and other well-established research methods in human rights and humanitarian practice, remotely sensed data can effectively geolocate and establish chronologies for mass graves, forced displacement, destruction of cultural heritage sites, and other violations. But as a highly technical field of science that relies on ever-changing technologies, remote sensing and geospatial analysis are not readily accessible for human rights and humanitarian practitioners. The community of practice grew out of innovative work by practitioners at NGOs and specialized inter-governmental …


Rhizobium Symbiotic Capacity Shapes Root-Associated Microbiomes In Soybean, Yuanhui Lu, Bin Ma, Wenfeng Chen, Klaus Schlaeppi, Matthias Erb, Erinne Stirling, Lingfei Hu, Entao Wang, Yunzeng Zhang, Kankan Zhao, Zhijiang Lu, Shudi Ye, Jianming Xu Dec 2021

Rhizobium Symbiotic Capacity Shapes Root-Associated Microbiomes In Soybean, Yuanhui Lu, Bin Ma, Wenfeng Chen, Klaus Schlaeppi, Matthias Erb, Erinne Stirling, Lingfei Hu, Entao Wang, Yunzeng Zhang, Kankan Zhao, Zhijiang Lu, Shudi Ye, Jianming Xu

Environmental Science and Geology Faculty Research Publications

Root-microbiome interactions are of central importance for plant performance and yield. A distinctive feature of legumes is that they engage in symbiosis with N2-fixing rhizobia. If and how the rhizobial symbiotic capacity modulates root-associated microbiomes are still not yet well understood. We determined root-associated microbiomes of soybean inoculated with wild type (WT) or a noeI mutant of Bradyrhizobium diazoefficiens USDA 110 by amplicon sequencing. UPLC-MS/MS was used to analyze root exudates. The noeI gene is responsible for fucose-methylation of Nod factor secreted by USDA 110 WT strain. Soybean roots inoculated with the noeI mutant showed a significant decrease …


2021 Fall Engr333 Poster, Section B, Calvin University 2021 Engr Section B Dec 2021

2021 Fall Engr333 Poster, Section B, Calvin University 2021 Engr Section B

ENGR 333

In 2020, residences used 21% of all final energy in the United States and were responsible for 20% of all U.S. carbon dioxide emissions (henceforth referred to as carbon emissions). Habitat for Humanity for Kent County is endeavoring to design homes that reduce energy consumption, energy expenditures, and carbon emissions. They have established a goal of a “low carbon footprint build” that will minimize energy consumption and carbon emissions, both during construction and across the lifetime of the house. To accomplish this goal, Habitat for Humanity for Kent County partnered with Calvin’s ENGR 333 – Thermal System Design and asked …


2021 Fall Engr333 Poster, Section A, Gerald Darkey, Jonathan Jansma, Chris Singh, Ryan Whitney, Adam Brunsting, Adam Tjoelker, Jack Van Der Molen, Cornelius Van Liere, Derrick Bittner, William Terpstra, Matthew Winkle, Kelsey Yen, Kasen Anderson, Jack Cahalane, Samantha Krupa, James Kulaga, Chukwudubem Nweke, Nathan Holwerda, Jacob Meulink, John Stehouwer, Isaac Spackman, Moses Yang Dec 2021

2021 Fall Engr333 Poster, Section A, Gerald Darkey, Jonathan Jansma, Chris Singh, Ryan Whitney, Adam Brunsting, Adam Tjoelker, Jack Van Der Molen, Cornelius Van Liere, Derrick Bittner, William Terpstra, Matthew Winkle, Kelsey Yen, Kasen Anderson, Jack Cahalane, Samantha Krupa, James Kulaga, Chukwudubem Nweke, Nathan Holwerda, Jacob Meulink, John Stehouwer, Isaac Spackman, Moses Yang

ENGR 333

Habitat for Humanity (HFH) built a low-carbon home at 726 London Street SW. Mark Ogland-hand, a representative of HFH, connected with Professor Matthew Heun to begin a carbon study of this new home with the goals of understanding the carbon footprints of a traditional HFH home, the London home, and future improvements feasible for HFH to make in reducing the carbon emissions of their houses.


Butte-Silver Bow Medical Monitoring Program Plan, Mike Mcanulty, Eric Hassler Dec 2021

Butte-Silver Bow Medical Monitoring Program Plan, Mike Mcanulty, Eric Hassler

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


How Community Participation In Water And Sanitation Interventions Impacts Human Health, Wash Infrastructure And Service Longevity In Low-Income And Middle-Income Countries: A Realist Review, Sarah Nelson, Dorothy Drabarek, Aaron Jenkins, Joel Negin, Seye Abimbola Dec 2021

How Community Participation In Water And Sanitation Interventions Impacts Human Health, Wash Infrastructure And Service Longevity In Low-Income And Middle-Income Countries: A Realist Review, Sarah Nelson, Dorothy Drabarek, Aaron Jenkins, Joel Negin, Seye Abimbola

Research outputs 2014 to 2021

Objective:

To understand how, and under what circumstances community participation in water and sanitation interventions impacts the availability of safe water and sanitation, a change in health status or behaviour and the longevity of water, sanitation and hygiene (WASH) resources and services.

Design:

Realist review.

Data sources:

PubMed, Web of Science and Scopus databases were used to identify papers from low-income and middle-income countries from 2010 to 2020.

Eligibility criteria for selecting studies:

Criteria were developed for papers to be included. The contribution of each paper was assessed based on its relevance and rigour (eg, can it contribute to context, …


Constraints To Waterfowl Hunting By Hunters And Anglers In The Central United States, Matthew P. Hinrichs, Matthew P. Gruntorad, Julia A. Nawrocki, Mark P. Vrtiska, Mark A. Pegg, Christopher J. Chizinski Dec 2021

Constraints To Waterfowl Hunting By Hunters And Anglers In The Central United States, Matthew P. Hinrichs, Matthew P. Gruntorad, Julia A. Nawrocki, Mark P. Vrtiska, Mark A. Pegg, Christopher J. Chizinski

School of Natural Resources: Faculty Publications

Waterfowl hunting participation has been on the decline since the mid‐1980s. We used a web‐based survey to better understand waterfowl hunting constraints (i.e., factors that limit or prohibit participation and enjoyment in leisure activities) among hunters and anglers that hunted or did not hunt waterfowl in the central United States. Forty‐eight constraint items were condensed into 10 constraint factors: Rules and Regulations, Waterfowl Identification, Cost, Waterfowl Hunting Skills, Land Access and Permissions, Interference by Other Hunters, Travel, Social, Waterfowl Populations, and Views of Others. We observed significant effects of both state of residence and activity type (i.e., frequent waterfowl hunters, …


A Physiological Signal Derived From Sun-Induced Chlorophyll Fluorescence Quantifies Crop Physiological Response To Environmental Stresses In The U.S. Corn Belt, Hyungsuk Kimm, Kaiyu Guan, Chongya Jiang, Guofang Miao, Genghong Wu, Andrew Suyker, Elizabeth A. Ainsworth, Carl J. Bernacchi, Christopher M. Montes, Joseph A. Berry, Xi Yang, Christian Frankenberg, Min Chen, Philipp Köhler Dec 2021

A Physiological Signal Derived From Sun-Induced Chlorophyll Fluorescence Quantifies Crop Physiological Response To Environmental Stresses In The U.S. Corn Belt, Hyungsuk Kimm, Kaiyu Guan, Chongya Jiang, Guofang Miao, Genghong Wu, Andrew Suyker, Elizabeth A. Ainsworth, Carl J. Bernacchi, Christopher M. Montes, Joseph A. Berry, Xi Yang, Christian Frankenberg, Min Chen, Philipp Köhler

School of Natural Resources: Faculty Publications

Sun-induced chlorophyll fluorescence (SIF) measurements have shown unique potential for quantifying plant physiological stress. However, recent investigations found canopy structure and radiation largely control SIF, and physiological relevance of SIF remains yet to be fully understood. This study aims to evaluate whether the SIF-derived physiological signal improves quantification of crop responses to environmental stresses, by analyzing data at three different spatial scales within the U.S. Corn Belt, i.e. experiment plot, field, and regional scales, where ground-based portable, stationary and space-borne hyperspectral sensing systems are used, respectively. We found that, when controlling for variations in incoming radiation and canopy structure, crop …


Application Of Upscaling Methods For Fluid Flow And Mass Transport In Multi-Scale Heterogeneous Media, Xiaoying Zhang, Funing Ma, Shangxian Yin, Corey D. Wallace, Mohamad Reza Soltanian, Zhenxue Dai, Robert W. Ritzi, Ziqi Ma, Chuanjun Zhan, Xiaoshu Lü Dec 2021

Application Of Upscaling Methods For Fluid Flow And Mass Transport In Multi-Scale Heterogeneous Media, Xiaoying Zhang, Funing Ma, Shangxian Yin, Corey D. Wallace, Mohamad Reza Soltanian, Zhenxue Dai, Robert W. Ritzi, Ziqi Ma, Chuanjun Zhan, Xiaoshu Lü

Earth and Environmental Sciences Faculty Publications

Physical and biogeochemical heterogeneity dramatically impacts fluid flow and reactive solute transport behaviors in geological formations across scales. From micro pores to regional reservoirs, upscaling has been proven to be a valid approach to estimate large-scale parameters by using data measured at small scales. Upscaling has considerable practical importance in oil and gas production, energy storage, carbon geologic sequestration, contamination remediation, and nuclear waste disposal. This review covers, in a comprehensive manner, the upscaling approaches available in the literature and their applications on various processes, such as advection, dispersion, matrix diffusion, sorption, and chemical reactions. We enclose newly developed approaches …


The Potential Of Remotely Sensed Vegetation Indices For Monitoring Pasture Condition, Pouria Ramzi, Karen Holmes Dec 2021

The Potential Of Remotely Sensed Vegetation Indices For Monitoring Pasture Condition, Pouria Ramzi, Karen Holmes

Resource management technical reports

The Department of Primary Industries and Regional Development (DPIRD) is developing an integrated monitoring system using remote sensing and on-ground measurements to track pasture condition across Western Australia’s pastoral region. We extended and adapted the methods developed in the Pastoral Lease Assessment Using Geospatial Analysis (PLAGA) project (Robinson et al. 2012), which combined remotely sensed vegetation indices (VIs) with on-ground pasture condition observations to assess the potential of using different vegetation indices in a statewide condition monitoring system.

There were 6 regions in WA’s pastoral rangelands with DPIRD on-ground condition traverse points: Kimberley and Broome, Pilbara, Yalgoo and Sandstone, Goldfields, …


Community Perceptions And Aesthetic Valuation Of Remediation Gardens, Rachel Bechtold Dec 2021

Community Perceptions And Aesthetic Valuation Of Remediation Gardens, Rachel Bechtold

Graduate Theses and Dissertations

Creating successfully remediated landscapes may rely on both natural resources and human perception in landscape design. Urban areas present a dynamic environment wherein communities and nature compete for resources and space. This dissertation study was designed to better understand aesthetic perceptions of native plants capable of land remediation in midwestern communities. Findings from this study show the importance of aesthetic perceptions of stakeholders towards rehabilitated landscapes and the importance of organizing indicators for future design decisions in an interdisciplinary fashion. Recommendations include continued evaluation of aesthetic perceptions for plant species in urban landscapes and modeling a more consistent framework for …


2021 Fall Engr333 Seminar Presentation, Anika Huizinga, John Stehouwer, William Terpstra, Duncan Waanders Dec 2021

2021 Fall Engr333 Seminar Presentation, Anika Huizinga, John Stehouwer, William Terpstra, Duncan Waanders

ENGR 333

File for student presentation, given by students in the Fall 2021 class of ENGR333.


Implications Of Condition Shifts On Shallow Lakes, Alicia Skolte Dec 2021

Implications Of Condition Shifts On Shallow Lakes, Alicia Skolte

Biology Graduate Theses

Shallow lakes have undergone condition shifts throughout time by natural causes, management actions, or a combination of the two. Because shallow lakes are especially vulnerable to shifts towards turbid conditions, management actions on shallow lakes have focused on water level/retainment, biomanipulations, the management/removal of non-native species, and land-use changes. This review compiles a summary on ecosystem shifts including a discussion on the frequency of shifts historically and the importance and causes of those shifts, trophic cascades, and the influence of introduced species in shallow lakes. This review will then examine case-studies of management-linked shifts and explain current shift theory. Next, …


Feeding Patterns And Diet Overlap Of Muskellunge And Co-Occurring Piscivores In Minnesota Lakes, Kamden Glade Dec 2021

Feeding Patterns And Diet Overlap Of Muskellunge And Co-Occurring Piscivores In Minnesota Lakes, Kamden Glade

Biology Graduate Theses

Muskellunge Esox masquinongy are the largest member of the family Esocidae found in Minnesota and are managed for trophy angling opportunities with large minimum size requirements, limited harvest, and stocking to support existing populations or expand angling opportunities. While Muskellunge impacts at the community level appear minimal based on available literature, relatively little is known about Muskellunge diets, eat the le particularly in Minnesota. In this study, we used gastric lavage to examine gut contents of Muskellunge, Northern Pike Esox lucius, Walleye Sander vitreus, and Largemouth Bass Micropterus salmoides. Diets were quantified using an index of relative importance (IRI) and …


Six-Fold Increase Of Atmospheric Pco2 During The Permian–Triassic Mass Extinction, Yuyang Wu, Daoliang Chu, Jinnan Tong, Haijun Song, Jacopo Dal Corso, Paul B. Wignall, Huyue Song, Yong Du, Ying Cui Dec 2021

Six-Fold Increase Of Atmospheric Pco2 During The Permian–Triassic Mass Extinction, Yuyang Wu, Daoliang Chu, Jinnan Tong, Haijun Song, Jacopo Dal Corso, Paul B. Wignall, Huyue Song, Yong Du, Ying Cui

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The Permian–Triassic mass extinction was marked by a massive release of carbon into the ocean-atmosphere system, evidenced by a sharp negative carbon isotope excursion. Large carbon emissions would have increased atmospheric pCO2 and caused global warming. However, the magnitude of pCO2 changes during the PTME has not yet been estimated. Here, we present a continuous pCO2 record across the PTME reconstructed from high-resolution δ13C of C3 plants from southwestern China. We show that pCO2 increased from 426 +133/−96 ppmv in the latest Permian to 2507 +4764/−1193 ppmv at the PTME within about 75 kyr, and that the reconstructed …


Iron Geochemistry Across An Estuary-To-Coastal Gradient, Lissett G. Diaz Dec 2021

Iron Geochemistry Across An Estuary-To-Coastal Gradient, Lissett G. Diaz

Honors Theses

Iron is a ubiquitous earth element that participates in biogeochemical processes that occur in marine sediments. Microorganisms utilize iron for many purposes, including cell growth, conserving energy, and for maintaining metabolic activity. In coastal sedimentary settings, understanding the redox reactions involving ferric iron, Fe3+, and ferrous iron, Fe2+, in its solid phase and pore-water phases, respectively, enable an appreciation of biogeochemical transformations occurring in the coastal zone. In this study, iron concentrations in sediment of ranging permeability were determined at four stations marking an estuary-coast transition zone in Singleton Swash in Myrtle Beach, South Carolina. The …


Iowa Waste Reduction Center Newsletter, December 2021, University Of Northern Iowa. Iowa Waste Reduction Center. Dec 2021

Iowa Waste Reduction Center Newsletter, December 2021, University Of Northern Iowa. Iowa Waste Reduction Center.

Iowa Waste Reduction Center Newsletter

Contents:

--- End of 2021 Director Address
--- Calendar
--- Welcome, Megan!
--- Saying Goodbye! : David Hindman - Elle Olthoff - Brandon Stenger
--- IGCB Awards New Gold-Level Breweries
--- 2022-2023 Recordkeeping Compliance Calendars for Dry Cleaners
--- 2022-2023 Compliance Calendar/Logbook for Bulk Gasoline Plants
--- Industry News


Understanding Students’ Global Interdependence In Science Instruction, Walter S. Smith Dec 2021

Understanding Students’ Global Interdependence In Science Instruction, Walter S. Smith

Journal of Global Education and Research

Multiple American educational organizations such as the National Education Association, Association for Supervision and Curriculum Development, and the Council of Chief State School Officers have advocated for globalizing the K-12 curriculum. The National Science Teaching Association (NSTA) in a position statement on international education and the Next Generation Science Standards have produced goals and standards for internationalizing the science curriculum by addressing topics such as climate change, environment, and disease that cross borders. In contrast to those pronouncements on the curriculum, this article views global science education through an instructional lens that focuses on a students’ global interdependence in science …


Comparison Of Different Analytical Strategies For Classifying Invasive Wetland Vegetation In Imagery From Unpiloted Aerial Systems (Uas), Louis Will Jochems, Jodi Brandt, Andrew Monks, Megan Cattau, Nicholas Kolarik, Jason Tallant, Shane Lishawa Dec 2021

Comparison Of Different Analytical Strategies For Classifying Invasive Wetland Vegetation In Imagery From Unpiloted Aerial Systems (Uas), Louis Will Jochems, Jodi Brandt, Andrew Monks, Megan Cattau, Nicholas Kolarik, Jason Tallant, Shane Lishawa

Human-Environment Systems Research Center Faculty Publications and Presentations

Detecting newly established invasive plants is key to prevent further spread. Traditional field surveys are challenging and often insufficient to identify the presence and extent of invasions. This is particularly true for wetland ecosystems because of difficult access, and because floating and submergent plants may go undetected in the understory of emergent plants. Unpiloted aerial systems (UAS) have the potential to revolutionize how we monitor invasive vegetation in wetlands, but key components of the data collection and analysis workflow have not been defined. In this study, we conducted a rigorous comparison of different methodologies for mapping invasive Emergent (Typha …


Supercritical Co2 Recompression Closed Brayton Cycle Analysis, Andres Eduardo Gutierrez Hernandez Dec 2021

Supercritical Co2 Recompression Closed Brayton Cycle Analysis, Andres Eduardo Gutierrez Hernandez

Open Access Theses & Dissertations

On this research, the results of an analysis made of a Supercritical Carbon Dioxide (sCO2) Recuperated Closed Brayton Cycle (RCBC) done by performing theorical calculations and comparing it to the results obtained with the use of the software ASPEN Plus will be presented. To demonstrate and determine that this software is a useful tool for modeling the proposed type of cycle, a preliminary comparison was made to verify with previous studies found in literature. A comparison and analysis between the possible working fluids and thermal energy sources was also performed to emphasize the decision of using CO2 as the cycle …


Use Patterns And Influencing Factors Of Irrigation Best Management Practices In The Lower Mississippi River Basin, Merri E. Day Dec 2021

Use Patterns And Influencing Factors Of Irrigation Best Management Practices In The Lower Mississippi River Basin, Merri E. Day

Graduate Theses and Dissertations

This study uses the 2016 Irrigation Survey from Arkansas, Louisiana, and Mississippi to document the use of irrigation best management practices (IBMPs), analyze use patterns, and use quantitative methods to determine factors that influence producers’ decisions regarding IBMPs. IBMPs included in the survey can be grouped as: field management practices (zero-grade leveling, precision-grade leveling, end blocking, warped surface, and deep tillage), water flow control practices (computerized pipe-hole selection, multiple-inlet irrigation, surge irrigation, alternate wetting and drying, cutback irrigation, flow meters, and pump timers), water recovery/storage practices (tail-water recovery system and on-farm storage reservoir), and advanced irrigation scheduling practices (soil moisture …


Using Iphone Significant Location Data To Improve Air Pollution Exposure Estimation, Elizabeth Eastman Dec 2021

Using Iphone Significant Location Data To Improve Air Pollution Exposure Estimation, Elizabeth Eastman

Electronic Theses and Dissertations, 2020-2023

An accurate estimation of human exposure to ambient air pollution is crucial for air pollution health studies. Time-activity patterns may introduce substantial uncertainties in exposure estimation. As smartphones are becoming increasingly popular and their ownership is becoming ubiquitous in the US. Virtually all smartphones can collect location data, and such data is continuously somewhere. Therefore, it is clear that such stored location data has the potential to be used for characterizing an individual's time-activity patterns for air pollution health studies. However, studies on the accuracy and feasibility of using a smartphone's location data in air pollution exposure estimation are still …


Characteristics Of Flow Over Rectangular Labyrinth Weirs With Round Corners, Omed S.Q. Yousif, Kawa Z. Abdulrahman, Wazira Qadir, Ahang S. Ali, Moses Karakouzian Dec 2021

Characteristics Of Flow Over Rectangular Labyrinth Weirs With Round Corners, Omed S.Q. Yousif, Kawa Z. Abdulrahman, Wazira Qadir, Ahang S. Ali, Moses Karakouzian

Civil and Environmental Engineering and Construction Faculty Research

The hydraulic performance of round-cornered rectangular labyrinth weirs with varying weir heights and effective lengths has not been explored in the existing literature to the authors’ knowledge. The purpose of this experimental study was to see how the height and effective length of round-cornered rectangular labyrinth weirs affect their discharge efficiency. Nine flat-crested rectangular labyrinth weirs made of high-density polyethylene (HDPE) were tested in a rectangular flume under various discharges to fulfill the goals of this study. The discharge coefficients for the weirs were then calculated. The hydraulic efficiency of weirs with round corners increases as the weir height (P) …


A Tighter Constraint On Earth-System Sensitivity From Long-Term Temperature And Carbon-Cycle Observations, Tony E. Wong, Ying Cui, Dana L. Royer, Klaus Keller Dec 2021

A Tighter Constraint On Earth-System Sensitivity From Long-Term Temperature And Carbon-Cycle Observations, Tony E. Wong, Ying Cui, Dana L. Royer, Klaus Keller

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The long-term temperature response to a given change in CO2 forcing, or Earth-system sensitivity (ESS), is a key parameter quantifying our understanding about the relationship between changes in Earth’s radiative forcing and the resulting long-term Earth-system response. Current ESS estimates are subject to sizable uncertainties. Long-term carbon cycle models can provide a useful avenue to constrain ESS, but previous efforts either use rather informal statistical approaches or focus on discrete paleoevents. Here, we improve on previous ESS estimates by using a Bayesian approach to fuse deep-time CO2 and temperature data over the last 420 Myrs with a long-term carbon cycle …


Cover Crop Effects On Near-Surface Soil Aggregate Stability In The Southern Mississippi Valley Loess (Mlra 134), Chandler M. Arel Dec 2021

Cover Crop Effects On Near-Surface Soil Aggregate Stability In The Southern Mississippi Valley Loess (Mlra 134), Chandler M. Arel

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Intensive agricultural cultivation within major land resource area (MLRA) 134, the Southern Mississippi Valley Loess, has led to soil erosion, soil compaction, and the overall destabilization of near-surface soil aggregates. The use of cover crops during the agricultural offseason has been shown to help alleviate soil compaction and provide stabilizing effects against soil erosion, which are particularly important as the silty soils of MLRA 134 have a large erosion potential. This study evaluated the effects of cover crop and no-cover crop treatment on silt-loam soils within MLRA 134. Treatments were implemented during Fall 2018 and Fall 2019 and consisted of …