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The Contribution Of Local And Transport Processes To Phytoplankton Biomass Variability Over Different Timescales In The Upper James River, Virginia, Qubin Qin, Jian Shen 2018 Virginia Institute of Marine Science

The Contribution Of Local And Transport Processes To Phytoplankton Biomass Variability Over Different Timescales In The Upper James River, Virginia, Qubin Qin, Jian Shen

Articles

Although both local processes (photosynthesis, respiration, grazing, and settling), and transport processes (advective transport and diffusive transport) significantly affect local phytoplankton dynamics, it is difficult to separate their contributions and to investigate the relative importance of each process to the local variability of phytoplankton biomass over different timescales. A method of using the transport rate is introduced to quantify the contribution of transport processes. By combining the time-varying transport rate and high-frequency observed chlorophyll a data, we can explicitly examine the impact of local and transport processes on phytoplankton biomass over a range of timescales from hourly to annually. For ...


Initial Limnological Observations At Five Small Lakes In Southern Pacific Costa Rica, Sally P Horn, Erik N. Johanson, Kurt A. Haberyan, Mathew S. Boehm, Jessie L. Johanson, Maureen Sánchez P., Mario Hernández V. 2018 University of Tennessee, Knoxville

Initial Limnological Observations At Five Small Lakes In Southern Pacific Costa Rica, Sally P Horn, Erik N. Johanson, Kurt A. Haberyan, Mathew S. Boehm, Jessie L. Johanson, Maureen Sánchez P., Mario Hernández V.

Geography Publications and Other Works

Costa Rica has hundreds of lakes, many of which have never been described or sampled by limnologists. Here we summarize initial observations of five small (0.2–1.7ha) lakes located at low elevation (365–490m) in the cantón of Buenos Aries. We collected basic limnological data and samples during visits in 2013 and 2014, and compiled environmental and archaeological data for their surroundings as a contribution to the documentation of lake diversity in Costa Rica, and to support parallel investigations of indicators of environmental history preserved in the sediments of the lakes. Lagunas Carse, Los Mangos, Danta, and Ojo ...


What’S At Steak? The Political Discourse Of Emissions Intensity And Implications Of Animal Agriculture, Kalyn Simon 2018 The University of San Francisco

What’S At Steak? The Political Discourse Of Emissions Intensity And Implications Of Animal Agriculture, Kalyn Simon

Master's Theses

This thesis analyzes the international discourse of greenhouse gas emissions in relation to livestock production. Specific government ministries, research institutes, and multilateral organizations are framing a new strategy to mitigate emissions by using emissions intensity metrics. Emissions intensity is a ratio comparing emissions produced per unit of animal product as oppose to measuring absolute emissions. This research is acknowledged as a win-win scenario which allows for a reduction of greenhouse gas emissions while continuing production more efficiently. This thesis outlines the emergence of this metric in international discourse and the implications this shift has on the livestock sector globally. Ultimately ...


Breeding Season Ecology And Demography Of Lesser Scaup (Aythya Affinis) At Red Rock Lakes National Wildlife Refuge, Jeffrey M. Warren 2018 Utah State University

Breeding Season Ecology And Demography Of Lesser Scaup (Aythya Affinis) At Red Rock Lakes National Wildlife Refuge, Jeffrey M. Warren

All Graduate Theses and Dissertations

It is hypothesized that individuals make reproductive decisions based on current assessments of their physiological condition and environmental conditions. For female lesser scaup (Aythya affinis), breeding occurs after an energetically costly spring migration. Increasing fat reserves (i.e., ‘body condition’) prior to breeding allows a female to produce a larger clutch of eggs, but time spent gaining body condition is costly in terms of time allowed to raise ducklings before freezing conditions in the fall. In Chapter 2 I explored rate of pre-breeding body condition gain in female lesser scaup, and how that rate influenced clutch size. Spring phenology, measured ...


Seabird Distribution And Oil & Gas Potential Along The Northern Sea Route, Russia: An Arctic Marine Conservation Case Study, Meghan Kelly 2018 Clark University

Seabird Distribution And Oil & Gas Potential Along The Northern Sea Route, Russia: An Arctic Marine Conservation Case Study, Meghan Kelly

International Development, Community and Environment (IDCE)

Seabirds are indicator species for the marine environment. Their populations are simultaneously affected by access to food resources and anthropogenic pressures including direct disturbance and habitat degradation associated with industrial development (Parsons et al. 2007). Therefore, using seabird distribution as a policy-relevant indicator for the Arctic marine environment supports an ecosystem based management approach aimed at protecting sensitive habitats from increased offshore oil and gas development.

This research identifies seabird habitat in the Russian Arctic utilizing in situ seabird observations from the Northern Sea Route to create a species distribution model. The spatial location of these areas will be compared ...


Modelling The Influence Of Crop Density And Weather Conditions On Field Drying Characteristics Of Switchgrass And Maize Stover Using Random Forest, Amit Khanchi, Stuart J. Birrell, Robert B. Mitchell 2018 Iowa State University

Modelling The Influence Of Crop Density And Weather Conditions On Field Drying Characteristics Of Switchgrass And Maize Stover Using Random Forest, Amit Khanchi, Stuart J. Birrell, Robert B. Mitchell

Agricultural and Biosystems Engineering Publications

Field drying trials were conducted using both field baskets as well as grab sampling techniques to study drying behaviour of switchgrass and maize (corn) stover (CS). Environmental conditions such as hourly solar radiation, vapour pressure deficit (VPD), average wind speed, rainfall amount, harvesting method, and field operations such as swath density were used as variables for model development. A powerful classification-based algorithm, which uses a collection of decision trees called random forest (RF) was utilised to predict moisture content (MC) of switchgrass and CS on wet basis. RF predicted the MC of switchgrass and CS with a coefficient of determination ...


A Comparative Study Of The Role Of Values In Reasoning About Socio-Hydrological Issues In Undergraduate Students From Developed And Developing Countries, Destini Petitt 2018 University of Nebraska - Lincoln

A Comparative Study Of The Role Of Values In Reasoning About Socio-Hydrological Issues In Undergraduate Students From Developed And Developing Countries, Destini Petitt

Dissertations & Theses in Natural Resources

In a world that is becoming increasingly connected and exploited, it is essential to understand how students’ values influence socio-scientific reasoning, particularly when dealing with complex, multifaceted, ever-connected water-related issues. This research strives to better understand stakeholder reasoning to provide teachers and decision-makers with ways to implement those stakeholders’ ideals into choices about complex socio-hydrological issues. Moreover, with 96% of research behavioral research being conducted on peoples from developed countries – who only represent 17% of the world’s population – this study strives to understand how peoples from developing countries – who represent 83% of the world’s population – reason. For this ...


Investigating Mechanisms Of Hydraulic Conductivity Transience In Sandy Streambeds, Wilhelm Fraundorfer 2018 University of Nebraska - Lincoln

Investigating Mechanisms Of Hydraulic Conductivity Transience In Sandy Streambeds, Wilhelm Fraundorfer

Dissertations & Theses in Natural Resources

Streambed hydraulic conductivity (K) is known to be spatially and temporally heterogeneous, but few attempts to understand the controls on temporal variability have been made. This study documents temporal K transience and demonstrates how hydraulic, geophysical, and sedimentological methods can be combined to understand the processes that give rise to changes in streambed K. Falling head permeameter tests and slug tests were conducted to determine vertical K (Kv) and K (slug test K), respectively. These tests were repeated three times over a twelve-week period on the same grid at a depth of 0.5 meters below the bed of ...


The Impact Of Land Use On Nitrate-N Movement And Storage In The Vadose Zone Of The Hastings’ Whpa, Craig Adams 2018 University of Nebraska - Lincoln

The Impact Of Land Use On Nitrate-N Movement And Storage In The Vadose Zone Of The Hastings’ Whpa, Craig Adams

Dissertations & Theses in Natural Resources

Nebraska has one of the largest agricultural economies in the United States and relies heavily on irrigation and fertilizer application to maintain crop yields. Over-irrigation and continuous application of nitrogen (N) in many areas has led to accumulation of nitrate-N in soils and sediments throughout the state’s vadose zone. Because nitrate-N is both persistent and mobile, groundwater concentrations in many areas of Nebraska and other agriculturally intensive states are increasing. Nitrate-N contamination of public and private drinking water supplies that utilize groundwater are of particular concern. Vadose zone sampling is an important method for rapidly assessing the effect of ...


Monitoring The Abundance Of American Shad And River Herring In Virginia's Rivers - 2017 Annual Report, Eric J. Hilton, Rob Latour, Patrick E. McGrath, Brian Watkins, Ashleigh Magee 2018 Virginia Institute of Marine Science

Monitoring The Abundance Of American Shad And River Herring In Virginia's Rivers - 2017 Annual Report, Eric J. Hilton, Rob Latour, Patrick E. Mcgrath, Brian Watkins, Ashleigh Magee

Reports

This report describes the results of the twentieth year of a continuing study to estimate the relative abundance and assess the status of American shad (Alosa sapidissima) stocks in Virginia by monitoring the spawning runs in the James, York and Rappahannock rivers in spring 2017, evaluating hatchery programs, and contributing to coast-wide assessments (ASMFC 2007). We also report on two fishery-independent monitoring programs, one using staked gillnets in the Rappahannock River (year 2) and the other using anchor gillnets in the Chickahominy River (year 3; a major tributary of the James River),to determine relative abundance and stock structure for ...


Does Scale Matter? A Systematic Review Of Incorporating Biological Realism When Predicting Changes In Species Distributions, Sydne Record, Angela L. Strecker, Mao-Ning Tuanmu, Lydia Beaudrot, Phoebe Zarnetske, Jonathan Belmaker, Beth Gerstner 2018 Bryn Mawr College

Does Scale Matter? A Systematic Review Of Incorporating Biological Realism When Predicting Changes In Species Distributions, Sydne Record, Angela L. Strecker, Mao-Ning Tuanmu, Lydia Beaudrot, Phoebe Zarnetske, Jonathan Belmaker, Beth Gerstner

Environmental Science and Management Faculty Publications and Presentations

Background: There is ample evidence that biotic factors, such as biotic interactions and dispersal capacity, can affect species distributions and influence species’ responses to climate change. However, little is known about how these factors affect predictions from species distribution models (SDMs) with respect to spatial grain and extent of the models.

Objectives: Understanding how spatial scale influences the effects of biological processes in SDMs is important because SDMs are one of the primary tools used by conservation biologists to assess biodiversity impacts of climate change.

Data sources and study eligibility criteria: We systematically reviewed SDM studies published from 2003–2015 ...


Hawai'i Wildlife Fund V. County Of Maui, Lowell J. Chandler 2018 Alexander Blewett III School of Law at the University of Montana

Hawai'i Wildlife Fund V. County Of Maui, Lowell J. Chandler

Public Land and Resources Law Review

In Hawai’i Wildlife Fund v. County of Maui, the Ninth Circuit held that the plain language of the Clean Water Act provides jurisdiction over indirect discharges of pollutants from a point source into groundwater that is shown to be connected to navigable waters. The court found that studies confirmed pollutants entering the Pacific Ocean were fairly traceable to the County of Maui’s sewage disposal wells. In affirming the district court’s ruling, the Ninth Circuit held that Maui County violated the Clean Water Act by discharging pollutants into a navigable water without the required permit. The court also ...


A Hydrologic And Hydraulic Analysis Of Massie’S Creek Gorge, Greene County, Oh, Using Hec-Ras, Joshua W. Perez 2018 Cedarville University

A Hydrologic And Hydraulic Analysis Of Massie’S Creek Gorge, Greene County, Oh, Using Hec-Ras, Joshua W. Perez

The Research and Scholarship Symposium

Massie’s Creek is a small tributary of the Little Miami River, located in southwest Ohio near the village of Cedarville. For approximately 1.5 miles (2.4 km) it flows westward through the Indian Mound Reserve Park, an area which occasionally undergoes flooding. In the first ½ mile (0.8 km) of the park, the stream is confined by a deep gorge, 40 feet (12 m) or more tall, and quickly flattens to a meandering stream through the rest of the park. The present study describes the application of HEC-RAS with the integration of ArcGIS for steady flow analyses ...


Grain Size Analysis Of Massie’S Creek Near Flax Pond And Community Park, Andrew R. Rivera 2018 Cedarville University

Grain Size Analysis Of Massie’S Creek Near Flax Pond And Community Park, Andrew R. Rivera

The Research and Scholarship Symposium

The goal of this research is to better understand the stream bed conditions at the confluence of North Fork and South Fork Massie’s Creek next to Community Park in downtown Cedarville, OH. Stream depth as well as sediment type where determined as a result of field work done for this project. The depth data was then used to create a contour map of the pool behind the low-head dam that defines the lower boundary of the confluence area. Sediment distribution is represented on this map based on laboratory particle size analysis and gross piratical size analysis done in the ...


Marginalized Populations And Climate Change, Olayemi Fadahunsi 2018 College of Saint Benedict/Saint John's University

Marginalized Populations And Climate Change, Olayemi Fadahunsi

Sociology Student Work

This study investigates the impact of climate change on marginalized populations , and seeks to understand the strategies of climate activists from so-called Least Developed Countries, particularly small island nations, for influencing climate policy on the global stage. I conducted participant observation and interviews at the UNFCCC’s COP 21 in Paris, in order to understand how marginalized populations anticipate the future, solutions they have to mitigate the harmful effects of climate change, and how they saw themselves being represented at the conference.


A Socioeconomic Valuation Of Urban Wetland Ecosystems And Policy Recommendation For College Lake, Michael Dunmyer 2018 Lynchburg College

A Socioeconomic Valuation Of Urban Wetland Ecosystems And Policy Recommendation For College Lake, Michael Dunmyer

Student Scholar Showcase

The current dilemma of College Lake offers a unique case study for how urban ecosystems can not only subsist within cities but provide pivotal functions for them as well. With the potential for a dam-breaching storm event increasing in possibility with each passing year, concerns regarding the structural integrity of the College Lake dam in Lynchburg, VA have arisen. Such concerns have led the City of Lynchburg to consider reinforcement or removal of the dam in order to mitigate flood risks along the Blackwater Creek floodplain. Since its formation following the installation of the Depression-era dam, however, College Lake has ...


To Catch The Rain: Inspiring Stories Of Communities Coming Together To Harvest Their Own Rain, And How You Can Do It Too, Lonny Grafman 2018 Humboldt State University

To Catch The Rain: Inspiring Stories Of Communities Coming Together To Harvest Their Own Rain, And How You Can Do It Too, Lonny Grafman

Textbooks Series (imprint)

If water is life, rainwater is a fountain of life. The purpose of this book is to show how various communities have caught that fountain of life using rainwater catchment systems. This book looks at real, practical, global experiences of rainwater harvesting on individual, financially constrained, and community based levels through academic, mathematical and practical perspectives. This book can be used to learn practical skills, see inspiring examples, and to make math have more meaning. This book is for practitioners, DIYers, community members looking for water solutions, as well as for students and teachers in environmental science, environmental studies, sustainable ...


Renewable Energy: A Solution To Japan’S Energy Crisis, Sunny Kwan 2018 Murray State University

Renewable Energy: A Solution To Japan’S Energy Crisis, Sunny Kwan

Scholars Week

As world population increases steadily, fossil fuel deposits around the world continue to be consumed; estimates state that all current known deposits will run dry by 2088. Fossil fuel consumption not only causes environmental pollution, but its resulting greenhouse gases accelerate global warming, leading to destructive changes in climate patterns and rising sea levels. On one hand, fossil fuels are an indispensable part of daily life, but they also cause irreversible damage to the environment. On the other hand, renewable energy sources are more expensive and less convenient to develop compared to fossil fuels, but they are a great alternative ...


Africa's Urban Adaptation Transition Under A 1.5° Climate, Mark Pelling, Hayley Leck, Lorena Pasquini, Idowu Ajibade, Emanuel Osuteye, Susan Parnell, Shuaib Lwasa, Cassidy Johnson, Arabella Fraser, Alejandro Barcena, Soumana Boubacar 2018 King's College London

Africa's Urban Adaptation Transition Under A 1.5° Climate, Mark Pelling, Hayley Leck, Lorena Pasquini, Idowu Ajibade, Emanuel Osuteye, Susan Parnell, Shuaib Lwasa, Cassidy Johnson, Arabella Fraser, Alejandro Barcena, Soumana Boubacar

Geography Faculty Publications and Presentations

Highlights

• Everyday risk associated with inadequate basic infrastructure and poverty make even small natural hazards impactful in African cities.

• Enhanced development opportunity is the best for of risk reduction.

• Integrating risk reduction into development is constrained by donor priorities, fragmented city governance and data and monitoring gaps.

• Integrating risk reduction into development is enabled through community networks collaborating with city authorities, locally accountable leadership and improved risk data and forecasting.


A Comparison Of The Diel Cycle Of Modeled And Measured Latent Heat Flux During The Warm Season In A Colorado Subalpine Forest, Sean P. Burns, Sean C. Swenson, William R. Wieder, David M. Lawrence, Gordon B. Bonan, John F. Knowles, Peter D. Blanken 2018 CU + NCAR

A Comparison Of The Diel Cycle Of Modeled And Measured Latent Heat Flux During The Warm Season In A Colorado Subalpine Forest, Sean P. Burns, Sean C. Swenson, William R. Wieder, David M. Lawrence, Gordon B. Bonan, John F. Knowles, Peter D. Blanken

University Libraries Open Access Fund Supported Publications

Precipitation changes the physiological characteristics of an ecosystem. Because land-surface models are often used to project changes in the hydrological cycle, modeling the effect of precipitation on the latent heat flux E is an important aspect of land-surface models. Here we contrast conditionally sampled diel composites of the eddy-covariance fluxes from the Niwot Ridge Subalpine Forest AmeriFlux tower with the Community Land Model (CLM, version 4.5). With respect to measured E during the warm season: for the day following above-average precipitation, E was enhanced at midday by ≈40 W m−2 (relative to dry conditions), and nocturnal E increased ...


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