Fresh Water Studies Commons^™

Simulating The Impacts Of Irrigation Levels On Soybean Production In Texas High Plains To Manage Diminishing Groundwater Levels, Vaishali Sharda, Prasanna H. Gowda, Gary Marek, Isaya Kisekka, Chittaranjan Ray, Pradip Adhikari

Nebraska Water Center: Faculty Publications

There is an increasing need to strategize and plan irrigation systems under varied climatic conditions to support efficient irrigation practices while maintaining and improving the sustainability of groundwater systems. This study was undertaken to simulate the growth and production of soybean [Glycine max (L.)] under different irrigation scenarios. The objectives of this study were to calibrate and validate the CROPGRO-Soybean model under Texas High Plains’ (THP) climatic conditions and to apply the calibrated model to simulate the impacts of different irrigation levels and triggers on soybean production. The methodology involved combining short-term experimental data with long-term historical weather data (1951–2012), …

Transition Pathways To Sustainable Agricultural Water Management: A Review Of Integrated Modeling Approaches, Erin M.K. Haacker, Vaishali Sharda, Amanda M. Cano, R. Aaron Hrozencik, Agustin Nunez, Zachary Zambreski, Soheil Nozari, Garvey Engulu B, Smith, Lacey Moore, Sumit Sharma, Prasanna Gowda, Chittaranjan Ray, Meagan Schipanski, Reagan Waskom

Nebraska Water Center: Faculty Publications

Agricultural water management (AWM) is an interdisciplinary concern, cutting across traditional domains such as agronomy, climatology, geology, economics, and sociology. Each of these disciplines has developed numerous process-based and empirical models for AWM. However, models that simulate all major hydrologic, water quality, and crop growth processes in agricultural systems are still lacking. As computers become more powerful, more researchers are choosing to integrate existing models to account for these major processes rather than building new cross-disciplinary models. Model integration carries the hope that, as in a real system, the sum of the model will be greater than the parts. However, …

Umphlett Qci Dec 2018, Natalie A. Umphlett

HPRCC Personnel Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Mountain Snowpack

Water Resources and Drought

Agriculture

Temperature

Precipitation

Three-Dimensional Bedrock Channel Evolution With Smoothed Particle Hydrodynamics, Nick Richmond

Electronic Theses and Dissertations

Bedrock channels are responsible for balancing and communicating tectonic and climatic signals across landscapes, but it is difficult and dangerous to observe and measure the flows responsible for removing weakly-attached blocks of bedrock from the channel boundary. Consequently, quantitative descriptions of the dynamics of bedrock removal are scarce. Detailed numerical simulation of violent flows in three dimensions has been historically challenging due to technological limitations, but advances in computational fluid dynamics aided by high-performance computing have made it practical to generate approximate solutions to the governing equations of fluid dynamics. From these numerical solutions we gain detailed knowledge of the …

Margaret White Springs Recharge Study, Buffalo National River, North-Central Arkansas, Usa, Ashlon Elizabeth Leonard

Graduate Theses and Dissertations

Margaret White Springs (MWS) is one of the largest springs in the middle section of the Buffalo National River (BNR) and contributes several tens of cubic feet per second of flow to river discharge on average, yet the source of the water has not been fully studied or documented. The spring is located approximately 4 miles downstream from Robertson Hole, a losing reach of the river. At Robertson Hole the river loses a significant amount of flow to groundwater, which during the dry season (summer) can be as much as 100%. Flow in the main channel is re-established at MWS; …

Environmental Fate And Microbial Effects Of Monensin, Lincomycin, And Sulfamethazine Residues In Soil, Matteo D'Alessio, Lisa M. Durso, Daniel N. Miller, Brian Woodbury, Chittaranjan Ray, Daniel D. Snow

Nebraska Water Center: Faculty Publications

The impact of commonly-used livestock antibiotics on soil nitrogen transformations under varying redox conditions is largely unknown. Soil column incubations were conducted using three livestock antibiotics (monensin, lincomycin and sulfamethazine) to better understand the fate of the antibiotics, their effect on nitrogen transformation, and their impact on soil microbial communities under aerobic, anoxic, and denitrifying conditions. While monensin was not recovered in the effluent, lincomycin and sulfamethazine concentrations decreased slightly during transport through the columns. Sorption, and to a limited extent degradation, are likely to be the primary processes leading to antibiotic attenuation during leaching. Antibiotics also affected microbial respiration …

Spatial Variation In Throughfall, Soil, And Plant Water Isotopes In A Temperate Forest, Gregory R. Goldsmith, Scott T. Allen, Sabine Braun, Nadine Engbersen, Clara Romero González-Quijano, James W. Kirchner, Rolf T. W. Siegwolf

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Studies of stable isotopes of water in the environment have been fundamental to advancing our understanding of how water moves through the soil‐plant‐atmosphere continuum; however, much of this research focuses on how water isotopes vary in time, rather than in space. We examined the spatial variation in the δ¹⁸O and δ²H of throughfall and bulk soil water, as well as branch xylem and bulk leaf water of Picea abies (Norway Spruce) and Fagus sylvatica (Beech), in a 1 ha forest plot in the northern Alps of Switzerland. Means and ranges of water isotope ratios varied considerably …

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.

Resource Assessment Report Temperate Demersal Elasmobranch Resource Of Western Australia, Matias Braccini, Nick Blay, S. A. Hesp, Brett Molony

Fisheries research reports

This document provides a cumulative description and assessment of the TDER and all of the fishing activities (i.e. fisheries / fishing sectors) affecting this resource in WA. Future Resource Assessment Reports will assess the Statewide Sharks and Rays Resource. The report is focused on the temperate indicator species (whiskery, gummy, dusky and sandbar sharks) used to assess the suites of demersal sharks and rays that comprise this resource. These species are primarily captured by demersal gillnets used in the TDGDLF that operate in the West Coast and South Coast Bioregions. For the North Coast bioregion, no commercial fishing for sharks …

Algal Blooms In Arkansas Streams, Ponds, And Lakes, Bradley J. Austin, Brie Olsen, Tate Wentz, Brian E. Haggard

Fact Sheets

Did you know that algae are a natural part of ponds, lakes, streams, and rivers? These organisms grow in the water (plankton) and on rocks, plants, and other surfaces (periphyton) and sometimes periphyton slough off into the water (seston). Most of the time these algae are hardly noticeable in waterbodies; however, sometimes they can form very noticeable algal blooms.

Droughtscape- 2018 Fall, National Drought Mitigation Center

Droughtscape, Quarterly Newsletter of NDMC, 2007-

Contents

From the director.............. 2

Drought greatly improves in Southern Plains and South............. 3

Texas, Missouri, and Colorado logged late-summer impacts.............. 5

Memory, remote sensing and a new research methodology............. 8

Navigating the U.S. Drought Monitor......... 9

Planners discuss the barriers to effective drought mitigation planning............ 12

Exploring climate issues from a county management perspective.............. 13

Strategic Framework for Drought Risk Management and Enhancing Resilience in Africa..................... 14

Mena global policy forum looks from data to mitigation............. 15

About us............17

State-by-state drought classification table developed by NDMC graduate student........19

Umphlett Qci Sept 2018, Natalie Umphlett

HPRCC Personnel Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Drought

Water Resources

Agriculture

Temperature

Precipitation

Multiyear Patterns In Benthic Algal Fatty-Acid Compounds Under Agricultural Stress, Sarah Whorley, John Wehr

Articles & Book Chapters

Benthic algae are the nutritional base of most freshwater food webs. Here we consider the nutritional contribution of benthic algae in the form of fatty acids (FAs) over multiple seasons and years. Our study was conducted in the Upper Delaware River watershed (New York, USA), where best-management practices (BMPs) had been implemented over varying numbers of years (BMP age) to mitigate effects of agricultural activities in the watershed. We defined 4 BMP categories by the presence and duration of management used in each stream drainage prior to initiating our study: 1) reference (unaffected), 2) no BMP (agriculturally affected), 3) new …

Physical And Chemical Response Of Small, North Temperate Lakes To Recovery From Acidification And Climate Change, Amanda Gavin

Electronic Theses and Dissertations

As the rate of sulfate (SO42-) deposition continues to decline and climate is trending towards warmer and wetter conditions, the biogeochemical and physical response of small, north temperate lakes is variable. In this study, we observed long-term chemical trends combined with seasonal water temperature patterns in the context of climate change and recovery from acidification in two remote lake populations in Maine: 29 high elevation lakes and eight low elevation lakes. Small, temperate lakes are the most abundant type of lake, making them a widely representative study sample to consider. Maine’s high elevation lakes (>600m) could potentially provide unique …

Natural And Managed Watersheds Show Similar Responses To Recent Climate Change, Darren L. Ficklin, John T. Abatzoglou, Scott M. Robeson, Sarah E. Null, Jason H. Knouft

Watershed Sciences Faculty Publications

Changes in climate are driving an intensification of the hydrologic cycle and leading to alterations of natural streamflow regimes. Human disturbances such as dams, land-cover change, and water diversions are thought to obscure climate signals in hydrologic systems. As a result, most studies of changing hydroclimatic conditions are limited to areas with natural streamflow. Here, we compare trends in observed streamflow from natural and human-modified watersheds in the United States and Canada for the 1981–2015 water years to evaluate whether comparable responses to climate change are present in both systems. We find that patterns and magnitudes of trends in median …

Estimating Watershed Residence Times In Artificially-Drained Landscapes And Relation To Nutrient Concentrations, Emma Beck, Lisa Welp, Alexandra L. Meyer

The Summer Undergraduate Research Fellowship (SURF) Symposium

Nutrient runoff from agricultural lands feeds harmful algae blooms that create a variety of problems in freshwater ecosystems. In order to reduce the effects of this nutrient runoff, Best Management Practices (BMPs) are being put in place in agricultural lands. Most of these BMPs focus on slowing down the flow of water through the watershed to give nutrient concentrations time to deplete before the water flows to the stream or river. However, the effectiveness of these BMPs are highly unknown and the process of monitoring nutrient runoff is often complex and costly. The data in this study consists of 7 …

Estimating Watershed Mercury Contribution To Lake Fort Smith State Park, Arkansas, Usa, William Miles Harmon

Graduate Theses and Dissertations

Mercury contamination associated with human activities poses global human health and environmental risks. A fish-consumption advisory has been in effect at Lake Fort Smith in central west Arkansas for more than a decade due to observed methylmercury concentrations in fish tissue. Lake Fort Smith is an important municipal drinking water supply and recreational resource. Water samples from the majority contributing tributary stream, Frog Bayou creek, were collected periodically, under differing hydrologic conditions in order to quantify the allochthonous mercury load delivered to the lake. Temperature, specific conductance, and turbidity data were collected and used to estimate dissolved organic carbon, methylmercury …

Droughtscape- 2018 Summer, National Drought Mitigation Center

Droughtscape, Quarterly Newsletter of NDMC, 2007-

Contents

From the director.......................... 2

Drought expands and intensifies ............ 3

Dry down fuels fires ..................... 5

Tweeting #drought18.................... 7

MOISST and NSMN..................... 8

Caribbean planning progress .............. 9

Drought observer network study........... 10

MENA teams report progress ............. 12

NDMC global outreach............... 13

Climate hub workshop................ 15

On the horizon ........................... 16

Australian Herring And West Australian Salmon Scientific Workshop Report, October 2017, Department Of Primary Industries And Regional Development, Western Australia

Fisheries research reports

No abstract provided.

Shifting Niche Space In Coastal Landscapes: Spatio-Temporal Patterns Driving Submerged Aquatic Vegetation Across The Northern Gulf Of Mexico, Kristin Elise Demarco

LSU Doctoral Dissertations

Identifying distributions of submerged aquatic vegetation (SAV) across the northern Gulf of Mexico (NGOM) coastal landscape necessitates describing ecological processes in estuarine gradients. SAV assemblages are ecological indicators of aquatic ecosystem health; spatial and temporal distributions are strongly correlated to environmental conditions. Many wildlife species, including waterfowl, are dependent on SAV and seeds in NGOM coastal marshes for food and habitat. To understand SAV distributions at multiple spatial and temporal scales a multi-tiered project was designed to collect SAV presence, species assemblage, and cover data, and cores to describe seed food. The first tier sampled inter-annually in the growing seasons …

Umphlett Qci June 2018, Natalie Umphlett

HPRCC Personnel Publications

Highlights for the Basin

Temperature Anomalies

Precipitation Anomalies

Water Resources

Agriculture

Temperature

Precipitation

Calibration Parameter Selection And Watershed Hydrology Model Evaluation In Time And Frequency Domains, Karthik Kumarasamy, Patrick Belmont

Watershed Sciences Faculty Publications

Watershed scale models simulating hydrological and water quality processes have advanced rapidly in sophistication, process representation, flexibility in model structure, and input data. With calibration being an inevitable step prior to any model application, there is need for a simple procedure to assess whether or not a parameter should be adjusted for calibration. We provide a rationale for a hierarchical selection of parameters to adjust during calibration and recommend that modelers progress from parameters that are most uncertain to parameters that are least uncertain, namely starting with pure calibration parameters, followed by derived parameters, and finally measured parameters. We show …

Functions Of Ecosystems: Stream Metabolism As An Efficient And Effective Means To Gage The Health And Understand The Interworking Of Urban Streams In A Watershed Of Rock Island, Il, Ryan Johnson, Dr. Kevin Geedey

Celebration of Learning

Stream metabolism is a critical functional measure of stream health that integrates physical parameters like slope and discharge, with ecosystem functions like photosynthesis and respiration. Stream metabolism is widely studied; however, urban stream metabolism remains poorly understood. Stream metabolism was measured for five streams ranging from 1^st to 5^th orders from October 11^th to October 18^th 2017 and four streams ranging from 1^st to 4^th order from October 22^nd to 25^th 2017 located within an approximately 9.3 square kilometer watershed of Rock Island, IL that has an urban to suburban type of …

Changes In Soil Microbial Functioning In Coastal Wetlands Exposed To Environmental Stressors And Subsidies, Shelby M. Servais

FIU Electronic Theses and Dissertations

Environmental perturbations are ubiquitous features of ecosystems and shape ecological structure and function. Climate change will alter the intensity and frequency of disturbances and expose ecosystems to novel combinations of useful inputs (subsidies) and harmful inputs (stressors). Coastal wetlands are particularly vulnerable to changing environmental conditions and are increasingly exposed to effects of interacting subsidies and stressors. In particular, the Florida Coastal Everglades, which has experienced accelerated change due to a history of water management practices, is vulnerable to new disturbances associated with climate change. The low-lying Florida Everglades faces multiple disturbances from storm surge, nutrient enrichment, and sea-level rise …

Predicting Spatial Patterns In Precipitation Isotope (Δ2h And Δ18o) Seasonality Using Sinusoidal Isoscapes, Scott T. Allen, James W. Kirchner, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Understanding how precipitation isotopes vary spatially and temporally is important for tracer applications. We tested how well month‐to‐month variations in precipitation δ18O and δ2H were captured by sinusoidal cycles, and how well spatial variations in these seasonal cycles could be predicted, across Switzerland. Sine functions representing seasonal cycles in precipitation isotopes explained between 47% and 94% of the variance in monthly δ18O and δ2H values at each monitoring site. A significant sinusoidal cycle was also observed in line‐conditioned excess. We interpolated the amplitudes, phases, and offsets of these sine functions across the landscape, using multiple linear …

Cyanobacteria Reduce Quagga Mussel (Dreissena Rostriformis Bugensis) Spawning And Fertilization Success, Anna G. Boegehold, Nicholas S. Johnson, Jeffrey L. Ram, Donna R. Kashian

Environmental Science and Geology Faculty Research Publications

Quagga mussels (Dreissena rostriformis bugensis) are highly fecund broadcast spawners invasive to freshwaters of North America and western Europe. We hypothesized that environmental cues from phytoplankton can trigger gamete release in quagga mussels. Nutritious algae may stimulate dreissenid spawning, but less palatable food, such as bloom-forming cyanobacteria, could be a hindrance. The objective of our study was to test whether exposure to cyanobacteria can inhibit quagga mussel spawning and fertilization. We assessed spawning in the presence of serotonin, a known spawning inducer, where adult quagga mussels placed in individual vials were exposed to 13 cyanobacteria cultures and purified algal toxin …

Carbon Dynamics In Tropical Lake Malawi, Maxon Ngochera

Theses and Dissertations

Large lakes of the world play a vital role in the global carbon cycle as they act both as conduits and sinks of terrestrially and atmospherically derived carbon. Lake Malawi, lying at the extreme southernmost end of the East African Rift Valley is one of the largest, deepest and most ancient of the African Great Lakes. In this study, the spatial and seasonal variation of direct measurements of air and water pCO2 were taken for a period of one annual cycle using a vessel of opportunity along the north-south axis of Lake Malawi. These data, together with limnological and meteorological …

Applications Of Reservoir Limnology Theory And Steady-State Modeling To Eutrophication Management In Beaver Lake, Arkansas, Matthew Rich

Graduate Theses and Dissertations

Reservoir limnology theory predicts that phytoplankton biomass (PB) is greatest in riverine-transition zones and least in lacustrine zones leading to an inverse pattern in water clarity. These theoretical patterns were utilized to create a statistical model of chlorophyll-a (Chl-a), an indicator of PB, and Secchi transparency (ST), an indicator of Chl-a, in Beaver Lake, Arkansas, a 12,800-ha reservoir, in order to hindcast historical conditions. Sampling for Chl-a, ST, and photic depth occurred semimonthly at 12 locations along a 78-km transect from the river inflow to the dam during the 2015 growing season. The ratio of Chl-a and ST measured at …

A Geospatial Study Of The Drought Impact On Surface Water Reservoirs: Study Cases From Texas And California, Zachary Asbury

Graduate Theses and Dissertations

Drought in Texas and California has been a long-term problem. Over the past 60 years reservoir construction has occurred to remedy the situation. Satellite imagery has been used historically to measure and monitor fluctuations in surface water reservoirs. This investigation integrates remote sensing and geographic information system (GIS) technologies to study the impact of drought on selected surface water reservoirs in San Angelo and Dallas in Texas, and Lake Oroville in California. Expansion and shrinkage over the 2005-2016 period reveal the concrete impact that drought, along with other factors, have on the selected lakes. Fluctuations in reservoir sizes during summer …

Irrigation Practice Adoption: Causes And Consequences In The Arkansas Delta, Kerr James Adams

Graduate Theses and Dissertations

Concerns about groundwater depletion from conventional irrigation agriculture in the Arkansas Delta region have led to the promotion of more efficient irrigation practices. With Arkansas being the largest producer of rice, the 10th largest producer of soybeans and the 16th largest producer of corn in the United States, the irrigation demand of these crops has put pressure on producers to find ways to irrigate more efficiently. Not only are the alternative technologies supposed to reduce water use, it is also believed that their adoption can also yield economic benefits for the producer. Despite these assumed benefits, adoption of alternative technologies …