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Heavy Metals In Afforested Mangrove Sediment From The World's Largest Delta: Distributional Mapping, Contamination Status, Risk Assessment And Source Tracing, Md Saifur Rahman, Moshiur Rahman, Yeasmin N Jolly, Md Kamal Hossain, Sanjida Afrin Semme, Bilal Ahamad Paray, Takaomi Arai, Jimmy Yu, M Belal Hossain

Journal Articles

This study aims to assess seasonal and spatial variations, contamination status, ecological risks, and metal sources (Ni, Pb, Cr, Cu, Mn, and Zn) in human-afforested mangrove sediments in a deltaic region. Five sampling locations were sampled during dry and wet seasons. Heavy metal concentrations followed the order: Mn > Zn > Ni > Cr > Cu > Pb. Metal loads, except Cu and Pb, were higher during the dry season, aligning with national and international recommendations. Sediment quality guidelines, contamination factor, geoaccumulation index, enrichment factors, and pollution load index indicated uncontaminated sediment in both seasons. Potential ecological risk assessment showed low risk conditions in all …

Sturgeon Chub Distributional Patterns And Habitat Use And Benthic Fish Assemblage Structure In Missouri River Tributaries Of South Dakota, Mitchell R. Magruder

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

Native species of the Missouri River drainage inhabiting benthic habitats dominate state and federal lists of species at risk. Sicklefin Chub Macrhybopsis meeki and Sturgeon Chub Macrhybopsis gelida are two native Missouri River benthic minnows that are currently under review for federal listing under the Endangered Species Act (ESA) due to extensive population declines and local extirpations within their native range. Substantial alterations to the Missouri River threaten Macrhybopsis spp. and other benthic fishes; however, large, less impacted tributaries in South Dakota may act as refugia for native species. The extent of Sicklefin Chub and Sturgeon Chub populations is largely …

Exploring Old Data With New Tricks: Long-Term Monitoring Indicates Spatial And Temporal Changes In Populations Of Sympatric Prairie Grouse In The Nebraska Sandhills, Danielle J. Berger, Jeffrey J. Lusk, Larkin A. Powell, John P. Carroll

School of Natural Resources: Faculty Publications

The contiguous grasslands of the Sandhills region in Nebraska, USA, provide habitat for two sympatric, grassland-obligate species of grouse, the greater prairie-chicken (Tympanuchus cupido pinnatus) and the plains sharp-tailed grouse (Tympanuchus phasianellus jamesi). Collectively referred to as prairie grouse, these birds are monitored and managed jointly by wildlife practitioners who face the novel challenge of conserving historically allopatric species in shared range. We reconstructed region-wide and route-specific prairie grouse population trends in the Sandhills, using a 63-year timeseries of breeding ground counts aggregated from old reports and paper archives. Our objective was to repurpose historical data …

Species Distribution Modeling For Arid Adapted Habitat Specialists In Zion National Park, Sam Driver, Daniel R. Unger, David L. Kulhavy, Chris M. Schalk

Student Publications

The Arizona toad (Anaxyrus microscaphus) and Jones’ waxy dogbane (Cycladenia humilis var. jonesii) are habitat specialists with historical ranges in the desert southwest and specifically, Zion National Park (ZION). The machine learning method, MaxEnt, constructed species distribution models (SDMs) in ZION for the two study species at 30 m and 900 m spatial resolutions using climate, topographic, and remotely sensed data. Additionally, 900 m forecasting models were constructed to observe the shifts in suitable habitat for the years 2050 and 2070, based off two representative concentration pathway scenarios. Results indicate promising predictive power for both high …

A Multi-Scale Analysis Of Jaguar (Panthera Onca) And Puma (Puma Concolor) Habitat Selection And Conservation In The Narrowest Section Of Panama., Kimberly A. Craighead

Antioch University Full-Text Dissertations & Theses

Over the past two centuries, large terrestrial carnivores have suffered extreme population declines and range contractions resulting from the synergistic anthropogenic threats of land-use change and indirect effects of climate change. In Panama, rapid land use conversion coupled with climate change is predicted to negatively impact jaguar (Panthera onca) and puma (Puma concolor). This dissertation examined the environmental variables and scales influencing jaguar and puma habitat selection by season (annual, wet, and dry), using multi-scale optimized habitat suitability models and a machine-learning algorithm (Random Forests), in the narrowest section of Panama. The models derived from the data of an intensive …

Assessment Of The Ponderosa Woodlands In Nebraska's Wildcat Hills: Implications For Juniperus Encroachment And Management, Allie Victoria Schiltmeyer

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

Ponderosa pine (Pinus ponderosa) is a dominant tree species across western North America. Its eastern distribution includes three populations in western Nebraska. This study assesses the distribution, structure and age of ponderosa pine woodlands in one of those regions, the Wildcat Hills. The Wildcat Hills have escaped severe wildfires seen in recent decades in other ponderosa pine regions. Nevertheless, the Wildcat Hills woodlands face multiple threats including climate change, wildfire, drought, pine beetles, and invasive species. Key to these threats is the stand structure of pine woodlands, which have increased in density across much of ponderosa pine’s range. …

Discontinuities Concentrate Mobile Predators: Quantifying Organism-Environment Interactions At A Seascape Scale, Cristina G. Kennedy, Martha E. Mather, Joseph M. Smith, John T. Finn, Linda A. Deegan

Environmental Conservation Faculty Publication Series

Understanding environmental drivers of spatial patterns is an enduring ecological problem that is critical for effective biological conservation. Discontinuities (ecologically meaningful habitat breaks), both naturally occurring (e.g., river confluence, forest edge, drop-off) and anthropogenic (e.g., dams, roads), can influence the distribution of highly mobile organisms that have land- or seascape scale ranges. A geomorphic discontinuity framework, expanded to include ecological patterns, provides a way to incorporate important but irregularly distributed physical features into organism–environment relationships. Here, we test if migratory striped bass (Morone saxatilis) are consistently concentrated by spatial discontinuities and why. We quantified the distribution of 50 …

Habitat Use Of The Key Largo Woodrat (Neotoma Floridana Smalli), Lauren J. Barth

FIU Electronic Theses and Dissertations

Key Largo woodrats are an endangered subspecies with an extremely limited habitat. This study sought to understand woodrat habitat preferences in order to guide management. Woodrats build stick nests from natural and artificial materials, so nest distribution and nest occupancy were used as indicators of preference. Distribution was determined by nest surveys, and remote cameras were used to assess occupancy. Forest structure, human disturbance, nest, and animal presence metrics were also collected. More nests were found along abandoned roads than along forest transects and more artificial nests were occupied than natural nests. These findings indicate that woodrats prefer areas with …

Colorado River Water: Mexico's Perspective On The Ongoing Negotiations, Mario López Pérez

US-Mexico Negotiations on Improved Colorado River Management: An Update (February 19)

Presenter: Mario López, Engineering and Technical Standards Manager, National Water Commission of México

53 slides

Slides: Water Footprints: Consciousness Raising Meets Risk Management, Steve Malloch

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: Steve Malloch, Senior Western Water Program Manager, National Wildlife Federation, Seattle, WA

38 slides

Movements, Distribution, And Abundance Of Great Argus Pheasants (Argusianus Argus) In A Sumatran Rainforest, Nurul L. Winarni, Timothy G. O'Brien, John P. Carroll, Margaret F. Kinnaird

School of Natural Resources: Faculty Publications

We used radiotelemetry, habitat sampling, camera trapping, and line-transect surveys to explore movement patterns, distribution, and abundance of Great Argus Pheasants (Argusianus argus) in Sumatra, Indonesia. We radiotracked six adult and one subadult males. Territories averaged 14.5 ± 8.5 ha, and home-range size did not vary by month or by relative abundance of selected plant foods. Daily travel distance (849 ± 211 m) varied significantly between months but did not reflect changes in plant foods. Territories were used almost exclusively by resident males. Males preferentially used undisturbed forest (habitat I). Vegetation structure at male display sites and random points indicated …

Slides: Technologies To Reduce Methane Emissions From Natural Gas Production Activities, Roger Fernandez

Best Management Practices and Adaptive Management in Oil and Gas Development (May 12-13)

Presenter: Roger Fernandez, EPA Gas STAR Program

31 slides

Transboundary Water Conflicts And Cooperation, Aaron T. Wolf

Allocating and Managing Water for a Sustainable Future: Lessons from Around the World (Summer Conference, June 11-14)

14 pages.

Contains references (page 13) and endnotes (page 14).

Managing Water Resources For A Sustainable Future: Law, Policy And Methodology Of China, Xi Wang, Xiaobo Zhang, Wenkai Li, Dejin Gu, Yanfang Zhou

Allocating and Managing Water for a Sustainable Future: Lessons from Around the World (Summer Conference, June 11-14)

37 pages (includes color illustrations).

Contains references (pages 36-37).

Effects Of Ultraviolet Radiation On Attached Diatom Growth And Distribution, Heather Lynn Emsley Hatsell

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

No abstract provided.

Organizational Structure, Responsibilities And Authority: Northern Colorado Water Conservancy District, Larry Simpson

Water Organizations in a Changing West (Summer Conference, June 14-16)

3 pages.

Historic Trends In The Distribution And Populations Of Estuarine Marsh Birds Of The Connecticut River, Robert J. Craig

Storrs Agricultural Experiment Station

No abstract provided.

Toward Optimal Utilization Of Water Resources: The “Physical Solution", Harrison C. Dunning

Western Water: Expanding Uses/Finite Supplies (Summer Conference, June 2-4)

18 pages.