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Articles 2851 - 2880 of 4599
Full-Text Articles in Environmental Monitoring
Our Envirome, Spring/Summer 2019, Issue 40
Plastic Pollution, Fall/Winter 2019, Issue 39.3
Plastic Pollution, Fall/Winter 2019, Issue 39.3
Sustain Magazine
No abstract provided.
Plastic Pollution, Fall/Winter 2019, Issue 39.2
Plastic Pollution, Fall/Winter 2019, Issue 39.2
Sustain Magazine
No abstract provided.
Plastic Pollution, Fall/Winter 2019, Issue 39
Evolutionary History Predicts High‐Impact Invasions By Herbivorous Insects, Angela M. Mech, Kathryn A. Thomas, Travis D. Marsico, Daniel A. Herms, Craig R. Allen, Matthew P. Ayres, Kamal J.K. Gandhi, Jessica Gurevitch, Nathan P. Havill, Ruth A. Hufbauer, Andrew M. Liebhold, Kenneth F. Raffa, Ashley N. Schulz, Daniel R. Uden, Patrick C. Tobin
Evolutionary History Predicts High‐Impact Invasions By Herbivorous Insects, Angela M. Mech, Kathryn A. Thomas, Travis D. Marsico, Daniel A. Herms, Craig R. Allen, Matthew P. Ayres, Kamal J.K. Gandhi, Jessica Gurevitch, Nathan P. Havill, Ruth A. Hufbauer, Andrew M. Liebhold, Kenneth F. Raffa, Ashley N. Schulz, Daniel R. Uden, Patrick C. Tobin
Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications
1. A long‐standing goal of invasion biology is to identify factors driving highly variable impacts of non‐native species. Although hypotheses exist that emphasize the role of evolutionary history (e.g., enemy release hypothesis & defense‐free space hypothesis), predicting the impact of non‐native herbivorous insects has eluded scientists for over a century.
2. Using a census of all 58 non‐native conifer‐specialist insects in North America, we quantified the contribution of over 25 factors that could affect the impact they have on their novel hosts, including insect traits (fecundity, voltinism, native range, etc.), host traits (shade tolerance, growth rate, wood density, etc.), and …
How Characteristic Is The Species Characteristic Selection Scale?, Erica F. Stuber, Joseph J. Fontaine
How Characteristic Is The Species Characteristic Selection Scale?, Erica F. Stuber, Joseph J. Fontaine
Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications
Aim: The importance of framing investigations of organism–environment relationships to interpret patterns at relevant spatial scales is increasingly recognized. However, most research related to environmental relationships is single‐scaled, implicitly or explicitly assuming that a “species characteristic selection scale” exists. We tested the premise that a single characteristic scale exists to understand species– environment relationships within species by asking (a) what are the characteristic scales of species’ relationships with environmental predictors, and (b) is within species, cross‐predictor consistency in characteristic scales a general phenomenon.
Location: Nebraska, USA.
Time period: 2016.
Major taxa studied: Birds.
Methods: We used data from 86 species …
Operationalizing Ecological Resilience Concepts For Managing Species And Ecosystems At Risk, Jeanne C. Chambers, Craig R. Allen, Samuel A. Cushman
Operationalizing Ecological Resilience Concepts For Managing Species And Ecosystems At Risk, Jeanne C. Chambers, Craig R. Allen, Samuel A. Cushman
Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications
This review provides an overview and integration of the use of resilience concepts to guide natural resources management actions. We emphasize ecosystems and landscapes and provide examples of the use of these concepts from empirical research in applied ecology. We begin with a discussion of definitions and concepts of ecological resilience and related terms that are applicable to management. We suggest that a resilience-based framework for management facilitates regional planning by providing the ability to locate management actions where they will have the greatest benefits and determine effective management strategies. We review the six key components of a resilience-based framework, …
Drought Analyses Of The Horn´E PoˇZitavie Region (Slovakia) In The Period 1966–2013, Jaroslav Vido, Paulina Nalevankova, Jan Valach, Zbysek Sustek, Tsegaye Tadesse
Drought Analyses Of The Horn´E PoˇZitavie Region (Slovakia) In The Period 1966–2013, Jaroslav Vido, Paulina Nalevankova, Jan Valach, Zbysek Sustek, Tsegaye Tadesse
National Drought Mitigation Center: Faculty Publications
+is study focuses on the characterization of historical drought occurrences in the Horn´e Poˇzitavie region of Slovakia over the period 1966–2013 using Standardized Precipitation-Evapotranspiration Index (SPEI). Trend analyses were evaluated by the Mann–Kendall (MK) test as well as cumulative sum of rank difference (CRD) test. +e results showed that drought occurs in the region regularly (recurrent climate feature), while the trend analysis indicated the trend toward more arid climatic conditions. However, CRD trend analyses showed that the subtrend changed direction toward less drier conditions in the late 1980s and early 1990s. Analyses of SPEI trends in individual months showed a …
Estimating Live Fuel Moisture Using Smap L-Band Radiometer Soil Moisture For Southern California, Usa, Shenyue Jia, Seung Hee Kim, Son V. Nghiem, Menas Kafatos
Estimating Live Fuel Moisture Using Smap L-Band Radiometer Soil Moisture For Southern California, Usa, Shenyue Jia, Seung Hee Kim, Son V. Nghiem, Menas Kafatos
Mathematics, Physics, and Computer Science Faculty Articles and Research
Live fuel moisture (LFM) is a field-measured indicator of vegetation water content and a crucial observation of vegetation flammability. This study presents a new multi-variant regression model to estimate LFM in the Mediterranean ecosystem of Southern California, USA, using the Soil Moisture Active Passive (SMAP) L-band radiometer soil moisture (SMAP SM) from April 2015 to December 2018 over 12 chamise (Adenostoma fasciculatum) LFM sites. The two-month lag between SMAP SM and LFM was utilized either as steps to synchronize the SMAP SM to the LFM series or as the leading time window to calculate the accumulative SMAP SM. …
The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- July 2019, Natalie Umphlett, Rezaul Mamood, Paul Flanagan, Emily Brown, Gannon Rush, Crystal J. Stiles
The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- July 2019, Natalie Umphlett, Rezaul Mamood, Paul Flanagan, Emily Brown, Gannon Rush, Crystal J. Stiles
Prairie Post: Quarterly Newsletter of the High Plains Regional Climate Center
Inside this issue:
Message from the director........................................1
Staff spotlight...........................1
Spirit Lake workshop..............2
Product highlight....................3
Outreach events......................3
Research highlight..................4
Update on regional climate conditions..................................4
Northern Plains drought assessment................................5
Recent and upcoming travel and activities.............................6
Droughtscape, Fall 2019, Cory Matteson
Droughtscape, Fall 2019, Cory Matteson
DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)
Contents
From the Director
Quarterly drought summary
Quarterly drought impacts
Ranchers delayed response to drought
Drought Monitor celebrates 20 years
Drought Monitor state impact tables
Directorcontributesto U.N.droughtproject
Updated Drought Risk Atlas
New fact sheet lists recovery resources
Droughtscape, Summer 2019, Cory Matteson
Droughtscape, Summer 2019, Cory Matteson
DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)
Contents
From the Director
Quarterly drought summary
Quarterly drought impacts
NDMC welcomes African visitors
Ready for Drought game debuts
U.S. Virgin Islands added to USDM
Australian programmer visits NDMC
Upcoming events
Partnerships with NDMC extended
Analysis Of Flood Patterns In Adams County, Pennsylvania Utilizing Drone Technology And Computer Simulations, Alyssa J. Kaewwilai
Analysis Of Flood Patterns In Adams County, Pennsylvania Utilizing Drone Technology And Computer Simulations, Alyssa J. Kaewwilai
Student Publications
Drone imagery and photogrammetry models of the Gettysburg College campus and the terrain at Boyer Nurseries and Orchards were utilized to study flood patterns in Adams County, Pennsylvania. Gettysburg College has lower-sloped land and moderately built infrastructure while Boyer Orchards has drastically sloped land with many patches of abundant vegetation. The two locations were selected due to the fact that they have starkly different surface features, while the bedrock geology of the areas are very similar. The terrain of the models was isolated before a 3D carver and 3D printer were used to construct physical models to further analyze potential …
Investigation Of Grace-Derived Information On Forest Drought Stress Across The Contiguous Us, Beichen Zhang
Investigation Of Grace-Derived Information On Forest Drought Stress Across The Contiguous Us, Beichen Zhang
School of Natural Resources: Dissertations, Theses, and Student Research
This research derives z-score monthly groundwater storage (GWS) anomalies and z-score monthly root zone soil moisture (RZSM) anomalies from products of Gravity Recovery and Climate Experiment Data Assimilation (GRACE-DA). Z-score monthly GWS and RZSM anomalies are compared to two drought indicators: Standardized Precipitation Index (SPI) and Standardized Precipitation-Evapotranspiration Index (SPEI) to investigate the usefulness of GRACE-DA information to detect drought conditions at tree-ring sites. This study also compares z-score monthly GWS and RZSM anomalies with the Tree Ring Standardized Growth Index (TRSGI) that is resampled by bootstrapping to investigate the capability of monitoring forest drought stress. Finally, this research uses …
Data From: Microplastic Concentrations In Two Oregon Bivalve Species: Spatial, Temporal, And Species Variability, Britta Baechler, Elise F. Granek, Matthew V. Hunter, Kathleen E. Conn
Data From: Microplastic Concentrations In Two Oregon Bivalve Species: Spatial, Temporal, And Species Variability, Britta Baechler, Elise F. Granek, Matthew V. Hunter, Kathleen E. Conn
Environmental Science and Management Datasets
Microplastics are an ecological stressor with implications for ecosystem and human health when present in seafood. We quantified microplastic types, concentrations, anatomical burdens, geographic distribution, and temporal differences in Pacific oysters (Crassostrea gigas) and Pacific razor clams (Siliqua patula) from 15 Oregon coast, U.S.A. sites. Organisms were chemically digested and visually analyzed for microplastics, and material type was determined using Fourier Transform Infrared Spectroscopy. Microplastics were present in organisms from all sites. On average, whole oysters and razor clams contained 10.95 ± 0.77 and 8.84 ± 0.45 microplastic pieces per individual, or 0.35 ± 0.04 and …
Coral Reef Change Detection In Remote Pacific Islands Using Support Vector Machine Classifiers, Justin J. Gapper, Hesham El-Askary, Erik Linstead, Thomas Piechota
Coral Reef Change Detection In Remote Pacific Islands Using Support Vector Machine Classifiers, Justin J. Gapper, Hesham El-Askary, Erik Linstead, Thomas Piechota
Mathematics, Physics, and Computer Science Faculty Articles and Research
Despite the abundance of research on coral reef change detection, few studies have been conducted to assess the spatial generalization principles of a live coral cover classifier trained using remote sensing data from multiple locations. The aim of this study is to develop a machine learning classifier for coral dominated benthic cover-type class (CDBCTC) based on ground truth observations and Landsat images, evaluate the performance of this classifier when tested against new data, then deploy the classifier to perform CDBCTC change analysis of multiple locations. The proposed framework includes image calibration, support vector machine (SVM) training and tuning, statistical assessment …
Landscape Edges Shape Dispersal And Population Structure Of A Migratory Fish, Mark A. Kaemingk, S. E. Swearer, S. J. Bury, J. S. Shima
Landscape Edges Shape Dispersal And Population Structure Of A Migratory Fish, Mark A. Kaemingk, S. E. Swearer, S. J. Bury, J. S. Shima
Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications
Many freshwater organisms have a life-history stage that can disperse through seawater. This has obvious benefits for colonization and connectivity of fragmented sub-populations, but requires a physiologically challenging migration across a salinity boundary. We consider the role of landscape boundaries between freshwater and seawater habitats, and evaluate their potential effects on traits and developmental histories of larvae and juveniles (i.e., dispersing life-history stages) of an amphidromous fish, Galaxias maculatus. We sampled juvenile fish on their return to 20 rivers in New Zealand: 10 rivers had abrupt transitions to the sea (i.e., emptying to an open coastline); these were paired …
Incorporating Antecedent Soil Moisture Into Streamflow Forecasting, Abdoul Oubeidillah, Glenn Tootle, Thomas Piechota
Incorporating Antecedent Soil Moisture Into Streamflow Forecasting, Abdoul Oubeidillah, Glenn Tootle, Thomas Piechota
Mathematics, Physics, and Computer Science Faculty Articles and Research
This study incorporates antecedent (preceding) soil moisture into forecasting streamflow volumes within the North Platte River Basin, Colorado/Wyoming (USA). The incorporation of antecedent soil moisture accounts for infiltration and can improve streamflow predictions. Current Natural Resource Conservation Service (NRCS) forecasting methods are replicated, and a comparison is drawn between current NRCS forecasts and proposed forecasting methods using antecedent soil moisture. Current predictors used by the NRCS in regression-based streamflow forecasting include precipitation, streamflow persistence (previous season streamflow volume) and snow water equivalent (SWE) from SNOTEL (snow telemetry) sites. Proposed methods utilize antecedent soil moisture as a predictor variable in addition …
Umphlett Qci June 2019, Natalie Umphlett
Umphlett Qci June 2019, Natalie Umphlett
High Plains Regional Climate Center: Staff Publications
Highlights for the Basin
Temperature and Precipitation Anomalies
Soil Moisture Conditions
Delayed/Prevented Planting
Impacts to Cattle
Damage to Infrastructure
Temperature
Precipitation
Nutrients Mediate The Effects Of Temperature On Methylmercury Concentrations In Freshwater Zooplankton, Meredith P. Jordan, A. Robin Stewart, Collin A. Eagles-Smith, Angela L. Strecker
Nutrients Mediate The Effects Of Temperature On Methylmercury Concentrations In Freshwater Zooplankton, Meredith P. Jordan, A. Robin Stewart, Collin A. Eagles-Smith, Angela L. Strecker
Environmental Science and Management Faculty Publications and Presentations
Methylmercury (MeHg) bioaccumulation in freshwater aquatic systems is impacted by anthropogenic stressors, including climate change and nutrient enrichment. The goal of this study was to determine how warmer water temperatures and excess nutrients would alter zooplankton communities and phytoplankton concentrations, and whether those changes would in turn increase or decrease MeHg concentrations in freshwater zooplankton. To test this, we employed a 2 × 2 factorialexperimental design with nutrient and temperature treatments. Mesocosms were filled with ambient water and plankton from Cottage Grove Reservoir, Oregon, U.S.A., a waterbody that has experienced decades of elevated MeHg concentrations and …
The State Of Canada’S Birds 2019, North American Bird Conservation Initiative Canada
The State Of Canada’S Birds 2019, North American Bird Conservation Initiative Canada
Other Publications in Wildlife Management
BIRDS TELL US ABOUT THE HEALTH OF OUR WATER, AIR, AND LAND WE NEED TO LISTEN AND ACT
THE STATE OF CANADA’S BIRDS: Shorebirds, grassland birds, and aerial insectivores are in steep decline.
WATERFOWL AND WETLAND BIRDS CONSERVATION PARTNERSHIPS WORK
GRASSLAND BIRDS ARE RUNNING OUT OF TIME
SHOREBIRDS ARE LOSING GROUND
SEABIRDS A GLOBAL CONSERVATION CRISIS
FOREST BIRDS CONSERVATION WITHOUT BORDERS
BIRDS OF PREY AND AERIAL INSECTIVORES LEARNING FROM THE PAST
WHAT’S GOOD FOR BIRDS IS GOOD FOR US
CANADIANS ARE MONITORING THE STATE OF CANADA’S BIRDS
Ord River Irrigation Area Stage 2: M2 Supply Channel - Compliance Assessment Report 2018 - Statement 938, Kimberley Boab Consulting
Ord River Irrigation Area Stage 2: M2 Supply Channel - Compliance Assessment Report 2018 - Statement 938, Kimberley Boab Consulting
Reports
This compliance assessment of progress with the implementation of Ministerial Statement 938 for the period 1/1/2018 to 31/12/2018 was undertaken in late 2018 and early 2019 on behalf of the Proponent, the Western Australian Department of Primary Industries and Regional Development.
Assessment Of Agricultural Drought Considering The Hydrological Cycle And Crop Phenology In The Korean Peninsula, Chul-Hee Lim, Seung Hee Kim, Jong Ahn Chun, Menas Kafatos, Woo-Kyun Lee
Assessment Of Agricultural Drought Considering The Hydrological Cycle And Crop Phenology In The Korean Peninsula, Chul-Hee Lim, Seung Hee Kim, Jong Ahn Chun, Menas Kafatos, Woo-Kyun Lee
Mathematics, Physics, and Computer Science Faculty Articles and Research
Hydrological changes attributable to global warming increase the severity and frequency of droughts, which in turn affect agriculture. Hence, we proposed the Standardized Agricultural Drought Index (SADI), which is a new drought index specialized for agriculture and crops, and evaluated current and expected droughts in the Korean Peninsula. The SADI applies crop phenology to the hydrological cycle, which is a basic element that assesses drought. The SADI of rice and maize was calculated using representative hydrological variables (precipitation, evapotranspiration, and runoff) of the crop growing season. In order to evaluate the effectiveness of SADI, the three-month Standardized Precipitation Index, which …
Seamless Lidar Surveys Reveal Rates And Patterns Of Subsidence In The Mississippi River Delta, Celeste E. Woock
Seamless Lidar Surveys Reveal Rates And Patterns Of Subsidence In The Mississippi River Delta, Celeste E. Woock
LSU New Orleans Theses and Dissertations
Light Detection and Ranging (Lidar) data are used to report the temporal and spatial patterns of subsidence as well as the potential contributors to subsidence within the Barataria and Terrebonne Bays. In recent decades, subsidence in southeast Louisiana has become a topic of substantial and growing concern to the scientific community, the local residents, and all those invested in the region. Lidar data were acquired from the United States Geological Survey (USGS) and the LSU Center for Geoinformatics. The data has been manipulated to map the differenced Lidar, complete an instantaneous slope analysis, and determine the thickness of the Holocene …
An In-Situ Study Of The Aqueous Speciation Of Uranium (Vi) Under Hydrothermal Conditions, Diwash Dhakal
An In-Situ Study Of The Aqueous Speciation Of Uranium (Vi) Under Hydrothermal Conditions, Diwash Dhakal
Graduate Theses/Dissertations
Rigorous study of the speciation distribution of uranyl-chloride bearing solutions under hydrothermal conditions is important to understand the transport mechanism of uranium underground, which is of uttermost interest to parties studying the geological uranium deposits and those studying the possibilities of geological repositories for spent nuclear waste. I report an in-situ Raman spectroscopic study of the speciation distribution of aqueous uranyl-chloride complexes upto 500°C conducted using a HDAC as the high PT spectroscopic cell. The samples studied contained the species UO22+, UO2Cl+, UO2Cl20 and UO2Cl3- …
Using Numerical Models Of Dewatering At Coal Ash Impoundments To Understand Cost And Schedule, Peter Bell, Joel Thompson, Don Fuller
Using Numerical Models Of Dewatering At Coal Ash Impoundments To Understand Cost And Schedule, Peter Bell, Joel Thompson, Don Fuller
World of Coal Ash Proceedings
No abstract provided.
Investigating Ccr Units And Evaluating The Physical Properties Of Ponded Ccr, David Skeggs, Zahra Aghazadeh, Rachel Combs
Investigating Ccr Units And Evaluating The Physical Properties Of Ponded Ccr, David Skeggs, Zahra Aghazadeh, Rachel Combs
World of Coal Ash Proceedings
No abstract provided.
Demonstration Of “No Migration” Alternative Performance Standard For Ccr Facilities In Arid To Semi- Arid Regions Using Unsaturated Zone Modeling, James Aiken, Katy Lindstom
Demonstration Of “No Migration” Alternative Performance Standard For Ccr Facilities In Arid To Semi- Arid Regions Using Unsaturated Zone Modeling, James Aiken, Katy Lindstom
World of Coal Ash Proceedings
No abstract provided.
State Vs Federal Ccr Rule Regulations: Comparisons And Impacts, Nicole Kron, Eric Nelson
State Vs Federal Ccr Rule Regulations: Comparisons And Impacts, Nicole Kron, Eric Nelson
World of Coal Ash Proceedings
No abstract provided.
Coal Combustion Residuals Management Using Geotextile Containers- Considerations For Various Options, Randall Wilcox, Gregg Lebster, Bryan Hamilton, Thomas Stephens
Coal Combustion Residuals Management Using Geotextile Containers- Considerations For Various Options, Randall Wilcox, Gregg Lebster, Bryan Hamilton, Thomas Stephens
World of Coal Ash Proceedings
No abstract provided.