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Articles 391 - 420 of 1200

Full-Text Articles in Fresh Water Studies

Acoustic Survey For Estimating Density Of Anchovy Schools In The South Sea Of Korea, Eunbi Min, Eun-A Yoon, Sung-Tae Kim, Seong Yong Moon, Hyun Woo Kim, Shelly Salim, Taejong Kang, Doo-Jin Hwang May 2021

Acoustic Survey For Estimating Density Of Anchovy Schools In The South Sea Of Korea, Eunbi Min, Eun-A Yoon, Sung-Tae Kim, Seong Yong Moon, Hyun Woo Kim, Shelly Salim, Taejong Kang, Doo-Jin Hwang

Journal of Marine Science and Technology–Taiwan

No abstract provided.


Estimating The Sampling Efficiencies Of A Framed Midwater Trawl And Ring Net For Zooplankton Using An Acoustic Method, Zhen Lu, Tohru Mukai, Yasuzumi Fujimori, Kohji Iida May 2021

Estimating The Sampling Efficiencies Of A Framed Midwater Trawl And Ring Net For Zooplankton Using An Acoustic Method, Zhen Lu, Tohru Mukai, Yasuzumi Fujimori, Kohji Iida

Journal of Marine Science and Technology–Taiwan

It is well known that there is bias using different sampling gear, such as a framed midwater trawl (FMT) and a ring net, when measuring the density and length distribution of target species. This limit is characterized by the sampling efficiency of the gear. Acoustic monitoring can be used to determine the sampling efficiencies of this gear, as its noninvasive, wide-range sweeps provide more reliable estimates of absolute abundance of the target species. The density measured by the gear can then be standardized by multiplying the initial density measurement by the derived sampling efficiency. In this study, we compared the …


In Situ Broadband Acoustic Measurements Of Age-0 Walleye Pollock And Pointhead Flounder In Funka Bay, Hokkaido, Japan, Kohei Hasegawa, Naizheng Yan, Tohru Mukai May 2021

In Situ Broadband Acoustic Measurements Of Age-0 Walleye Pollock And Pointhead Flounder In Funka Bay, Hokkaido, Japan, Kohei Hasegawa, Naizheng Yan, Tohru Mukai

Journal of Marine Science and Technology–Taiwan

Measurements of the broadband acoustic backscattering from fish should improve acoustic discrimination between species. The pulse compression processing of broadband systems can be used to measure acoustic backscattering with high range resolution and improve signal-to-noise ratio. This may increase opportunities for in situ target strength (TS) measurements, the preferred method of collecting TS data. To evaluate the availability of TS spectra for acoustic discrimination, three Simrad EK80 wideband transceivers and split-beam transducers of 70, 120, and 200 kHz were used to collect in situ frequency responses of TS from age-0 juvenile walleye pollock and pointhead flounder, a swimbladderless flat-fish, distributed …


Volume Scattering And Echo Integration In Fisheries Acoustics Revisited, Masahiko Furusawa May 2021

Volume Scattering And Echo Integration In Fisheries Acoustics Revisited, Masahiko Furusawa

Journal of Marine Science and Technology–Taiwan

Echo integration is the most important method in fisheries acoustics. The basis of the method is volume scattering theory, and the theory assumes that many fish are randomly and homogeneously distributed broader than a beam spread. In actual acoustic surveys, however, we encounter various distributions for which these assumptions do not hold. It is the echo integration method that hypothetically fulfills these assumptions. In this paper, we review the volume scattering theory and the echo integration method historically and theoretically and confirm their bases. We then point out some misunderstandings affected by historical constraints such as the persistence of time …


Using Uncrewed Aerial Vehicles For Identifying The Extent Of Invasive Phragmites Australis In Treatment Areas Enrolled In An Adaptive Management Program, Colin Brooks, Charlotte Weinstein, Andrew Poley, Amanda Grimm, Nicholas Marion, Laura Bourgeau-Chavez, Dana Hansen, Kurt Kowalski May 2021

Using Uncrewed Aerial Vehicles For Identifying The Extent Of Invasive Phragmites Australis In Treatment Areas Enrolled In An Adaptive Management Program, Colin Brooks, Charlotte Weinstein, Andrew Poley, Amanda Grimm, Nicholas Marion, Laura Bourgeau-Chavez, Dana Hansen, Kurt Kowalski

Michigan Tech Publications, Part 1

Higher spatial and temporal resolutions of remote sensing data are likely to be useful for ecological monitoring efforts. There are many different treatment approaches for the introduced European genotype of Phragmites australis, and adaptive management principles are being integrated in at least some long-term monitoring efforts. In this paper, we investigated how natural color and a smaller set of near-infrared (NIR) images collected with low-cost uncrewed aerial vehicles (UAVs) could help quantify the aboveground effects of management efforts at 20 sites enrolled in the Phragmites Adaptive Management Framework (PAMF) spanning the coastal Laurentian Great Lakes region. We used object-based image …


Intangible Cultural Heritage: A Benefit To Climate-Displaced And Host Communities, Gül Aktürk, Martha B. Lerski May 2021

Intangible Cultural Heritage: A Benefit To Climate-Displaced And Host Communities, Gül Aktürk, Martha B. Lerski

Publications and Research

Climate change is borderless, and its impacts are not shared equally by all communities. It causes an imbalance between people by creating a more desirable living environment for some societies while erasing settlements and shelters of some others. Due to floods, sea level rise, destructive storms, drought, and slow-onset factors such as salinization of water and soil, people lose their lands, homes, and natural resources. Catastrophic events force people to move voluntarily or involuntarily. The relocation of communities is a debatable climate adaptation measure which requires utmost care with human rights, ethics, and psychological well-being of individuals upon the issues …


Thermoelectric Generation And Thermophysical Properties Of Metal Oxide Nanofluids, Xinran Hou, Rong-Tsu Wang, Shaowen Huang, Jung-Chang Wang Mar 2021

Thermoelectric Generation And Thermophysical Properties Of Metal Oxide Nanofluids, Xinran Hou, Rong-Tsu Wang, Shaowen Huang, Jung-Chang Wang

Journal of Marine Science and Technology–Taiwan

This study describes the comprehensive characterization of the diverse water-based nanofluids involving aluminum oxide, titanium dioxide, and zinc oxide nanoparticles, which were prepared through the two-step synthesis method assisted by a microemulsion ultrasound skill with effects of both weight-percent concentration (wt.%) in the range of 1.0% and 5.0% and between 20 oC and 40 0C. The mean cluster size, zeta potential, pH value, viscosity, thermal conductivity, absorbance, light absorption, and electrical charge density of the various nanofluids were surveyed by relative experiments. The results showed that the 2 wt.% Al2O3, 2 wt.% TiO2 …


Wireless Sensor Network-Based Monitoring Of Bridge Pile Foundations For Detecting Scouring Depth, Han-Tang Huang, H. Ping Tserng, Ruei-Yu Hou, Mirosław Skibniewski Mar 2021

Wireless Sensor Network-Based Monitoring Of Bridge Pile Foundations For Detecting Scouring Depth, Han-Tang Huang, H. Ping Tserng, Ruei-Yu Hou, Mirosław Skibniewski

Journal of Marine Science and Technology–Taiwan

Climate change brings about unprecedented increases in the occurrence of storms and flooding. In response to increased risk of bridge pier scouring, there is a need for increased safety monitoring of bridges. This paper presents a wireless sensor network (WSN) - based solution developed to measure micro-vibrations of a bridge pier. Test measurement values are converted with the use of the Fast Fourier Transform (FFT) method to obtain natural frequencies. Scouring depth of the pier is estimated with the use of a Finite Element Method model. WSN is used to collect the signal and to test data transmission stability in …


A New Fuzzy Dea Model For Solving The Mcdm Problems In Supplier Selection, Chi-Mao Tsai, Hsuan-Shih Lee, Guo-Ya Gan Mar 2021

A New Fuzzy Dea Model For Solving The Mcdm Problems In Supplier Selection, Chi-Mao Tsai, Hsuan-Shih Lee, Guo-Ya Gan

Journal of Marine Science and Technology–Taiwan

Supplier selection is a crucial task in supply chain management, and good supply chain management is essential to a company's ability to develop sustainably and gain the trust and satisfaction of its customers. In modern supply chain management, supplier selection often takes the form of a multi-criteria decision-making (MCDM) problem. Thus, to solve this problem, this study formulated a novel fuzzy MCDM model, which is based on the fuzzy data envelopment analysis model. This novel approach can transform the linguistic variables of assessment criteria into well-founded quantitative data for calculation. Moreover, our approach can effectively discriminate between decision-making units (both …


Evaluation Of The Human Discomfort Caused By Ship Vibrations, Laurentiu Picu, Eugen Rusu Mar 2021

Evaluation Of The Human Discomfort Caused By Ship Vibrations, Laurentiu Picu, Eugen Rusu

Journal of Marine Science and Technology–Taiwan

The present work analyzes the subjective responses of people exposed to transient vibrations caused by systems with a single degree of freedom. In this context, the main objective of the research was to identify the main effect of vibrations on people's well-being at work (in particular on vessels crew) and to discover those frequencies that lead to the greatest discomfort. In order to achieve this goal, 12 laboratory experiments were carried out involving ten male subjects in good health, aged between 28 and 42. The variables of the vibratory system considered are: acceleration (4.8 ÷ 8.6 m/s¡2), amplitude (1 ÷ …


Application Of Physically Based Semi-Distributed Hec-Hms Model For Flow Simulation In Tributary Catchments Of Kaohsiung Area Taiwan, Fiaz Hussain, Ray-Shyan Wu, Kai-Chun Yu Mar 2021

Application Of Physically Based Semi-Distributed Hec-Hms Model For Flow Simulation In Tributary Catchments Of Kaohsiung Area Taiwan, Fiaz Hussain, Ray-Shyan Wu, Kai-Chun Yu

Journal of Marine Science and Technology–Taiwan

Hydrologic modeling is a commonly used tool to understand the rainfallerunoff processes of gauged and ungauged catchments for proper quantitative estimation of water resources availability. In the present study, an attempt is made to simulate surface runoff using a physically based semi-distributed hydrological (HEC-HMS) model for four local-scale tributary catchments of Kaohsiung area Taiwan. The input physical parameters of the model were calculated and preprocessed in HEC-GeoHMS based on digital elevation model (DEM), land use, soil and hydro-meteorological data. The model performance was satisfactory with Nash Sutcliffe Efficiency (NSE) ¼ 0.51 to 0.86 and the coefficient of determination (R2) ¼ …


Evaluating Key Factors Of Container Shipping Lines From The Perspective Of High-Tech Industry Shippers, Chien-Lung Hsu, Tien-Chun Ho Mar 2021

Evaluating Key Factors Of Container Shipping Lines From The Perspective Of High-Tech Industry Shippers, Chien-Lung Hsu, Tien-Chun Ho

Journal of Marine Science and Technology–Taiwan

Because of the changes in customers' needs and demands created by the development of container transport in the 1960s, the global container transport business has become increasingly competitive. With the high-tech industry ranged with one of the few competitive industries in Taiwan from 2002, container shipping lines have been forced to implement innovative operating patterns to meet the evolving demands of the high-tech industry shippers. This study conducts a survey questionnaire of domestic high-tech industry shippers to explore the different factors affecting their selection of container shipping lines, evaluating the key influencing factors by maritime marketing's 4C framework: customer needs, …


Beach Topography Surveying Using Unmanned Aerial Vehicle Photogrammetry Technology, Hui-Ming Fang, Kuan-Tsung Chang, Sung-Shan Hsiao, Shih-Peng Chiang Mar 2021

Beach Topography Surveying Using Unmanned Aerial Vehicle Photogrammetry Technology, Hui-Ming Fang, Kuan-Tsung Chang, Sung-Shan Hsiao, Shih-Peng Chiang

Journal of Marine Science and Technology–Taiwan

The mechanisms of in situ topography changes must be identified for spatial planning in coastal areas. In this study, the authors used in situ direct measurement methods and indirect remote-sensing technologies to develop a method for beach topography surveillance. Unmanned aerial vehicles (UAVs) have advantages of high portability and mobility and low operating altitude. Therefore, a UAV was equipped with a lightweight camera and a positioning system that comprised a global positioning system and an inertial measurement unit. Aerial photogrammetry and aerial triangu-lation methods were adopted for matching image feature points to obtain the corresponding topographic points in the sand. …


Plant Community Response To The Combined Effects Of Elevation, And Simulated Nutrient And Sediment Loading In Sagittaria Lancifolia-Dominated Wetlands, Donnie Day Mar 2021

Plant Community Response To The Combined Effects Of Elevation, And Simulated Nutrient And Sediment Loading In Sagittaria Lancifolia-Dominated Wetlands, Donnie Day

LSU Master's Theses

Coastal wetlands are experiencing threats to their long-term sustainability brought about by the combined effects of relative sea-level rise and human modifications to hydrology, sediment delivery and nutrient loading. Restoration and management strategies can include adding sediment to the surface of deteriorating marshes to facilitate positive feedbacks among elevation, plant productivity, sediment trapping, and accretion; however, if delivered using nitrate-enriched river waters, belowground biomass and soil organic matter pools may be negatively affected, resulting in the acceleration of wetland loss. Overall, there is limited information on the combined effects of nutrient loading, sedimentation, and flooding dynamics in regulating feedbacks among …


Picking Up Where The Tmdl Leaves Off: Using The Partnership Wild And Scenic River Framework For Collaborative River Restoration, Alan R. Hunt, Meiyin Wu, Tsung-Ta David Hsu, Nancy Roberts-Lawler, Jessica T. Miller, Alessandra Rossi, Lee Lee Feb 2021

Picking Up Where The Tmdl Leaves Off: Using The Partnership Wild And Scenic River Framework For Collaborative River Restoration, Alan R. Hunt, Meiyin Wu, Tsung-Ta David Hsu, Nancy Roberts-Lawler, Jessica T. Miller, Alessandra Rossi, Lee Lee

Department of Biology Faculty Scholarship and Creative Works

The National Wild and Scenic Rivers Act protects less than ¼ of a percent of the United States’ river miles, focusing on free-flowing rivers of good water quality with outstandingly remarkable values for recreation, scenery, and other unique river attributes. It predates the enactment of the Clean Water Act, yet includes a clear anti-degradation principle, that pollution should be reduced and eliminated on designated rivers, in cooperation with the federal Environmental Protection Agency and state pollution control agencies. However, the federal Clean Water Act lacks a clear management framework for implementing restoration activities to reduce non-point source pollution, of which …


Comparing Interrelated Stress Measures To Differentiate Acute And Chronic Stress In Urban Freshwater Turtles, Katherine Caldwell Jan 2021

Comparing Interrelated Stress Measures To Differentiate Acute And Chronic Stress In Urban Freshwater Turtles, Katherine Caldwell

Honors Program Theses

As urban areas grow in size and number, there are increasing impacts on the wildlife. While some species adapt, others cannot thrive in these conditions. Stress is the biological response to a stimulus that threatens homeostasis, which can be used to understand the condition of an individual. While acute stress is beneficial for survival, chronic stress can lead to deleterious impacts. A majority of turtles can be classified as declining in number or endangered, yet there is little understanding of their physiological stress response. This study examined how various stress measures—including corticosterone (CORT) in plasma, nails and leeches, metabolic measures, …


The Quantitative Assessment Of Pond Scum: An Examination Of The Biogeochemistry Of Phosphorus Cycling In The Belgrade Lakes, Abbey M. Sykes Jan 2021

The Quantitative Assessment Of Pond Scum: An Examination Of The Biogeochemistry Of Phosphorus Cycling In The Belgrade Lakes, Abbey M. Sykes

Honors Theses

The internal recycling phosphorus in freshwater lake bottom sediments represents a significant source of hypolimnetic phosphorus (P) release for many of Maine’s lakes. In summer months, Maine lakes often thermally stratify and the lake hypolimnion develops anoxia, leading to a reduction in redox potential at the sediment-water interface. These reducing conditions facilitate the reductive dissolution of ferric iron, and, since phosphorus is often present in freshwater lake sediments as solid FeOOH-PO4 complexes, results in release of soluble phosphorus into the water column. Our current study presents field and laboratory data from sediment fractionation extractions designed to quantify concentrations of …


Aquatic Macrophyte Communities In Five Sibley County (Minnesota) Lakes And The Factors That Affect Their Distribution, Samuel A. Schmid Jan 2021

Aquatic Macrophyte Communities In Five Sibley County (Minnesota) Lakes And The Factors That Affect Their Distribution, Samuel A. Schmid

All Graduate Theses, Dissertations, and Other Capstone Projects

The purposes of this study are to 1) quantify the shifts in the macrophyte community structure of five lakes in Sibley County, and 2) to assess the relationships between the macrophyte communities and abiotic factors in these five lakes. In both the early and late growing season of 2019, point-intercept surveys were conducted on High Island Lake, Titlow Lake, Schilling Lake, Silver Lake, and Clear Lake. At each point, water depth was recorded, and all macrophytes sampled were identified and recorded as “present.” There was not a late season survey conducted for High Island Lake in 2019 due to a …


Development Of Environmental Metabarcoding Analysis For Use In Ecological Studies Of Aquatic Fungal And Oomycete Communities Using Nanopore Sequencing, Douglas Bennett Jan 2021

Development Of Environmental Metabarcoding Analysis For Use In Ecological Studies Of Aquatic Fungal And Oomycete Communities Using Nanopore Sequencing, Douglas Bennett

All Master's Theses

One of several factors contributing to amphibian decline are organisms called water molds (oomycetes), which parasitize and kill amphibian and fish eggs, larvae, and occasionally adults. Amphibian decline is one of the most difficult issues facing ecologists and conservationists to date; half of amphibian species are in severe decline and one third of amphibian species are facing extinction, threatening the stability of ecosystems globally. Multiple oomycete species are known to cause the disease saprolegniasis and contribute to amphibian decline; however, the full range of species involved is not presently known. This study evaluated the Oxford Nanopore minION DNA sequencer (R9.2 …


Trace Metals And The Environment: Studying The Behaviour Of Iceland’S Glacially Sourced Trace Metals, Owen Bailey Oct 2020

Trace Metals And The Environment: Studying The Behaviour Of Iceland’S Glacially Sourced Trace Metals, Owen Bailey

Independent Study Project (ISP) Collection

Trace metal contamination in marine ecosystems is a problem for every trophic level, from zooplankton up to humans. The mobility and uptake availability of these metals depend on such environmental parameters as salinity, temperature, and pH, among others. To explore the effects of varying parameters on dissolved metal behaviour, I studied the Jökulsárlón glacial lagoon, into which the Breidamerkurjökull glacier deposits trace metals from volcanic ash through glacial melt. In this study I develop and follow a sampling procedure to analyze trace metal concentrations in the lagoon, while additionally discussing the behaviour and impact of trace metals, focusing on cadmium, …


Paleoenvironmental Reconstruction Of Quaternary Saltville, Virginia, Using Ostracode Autecology, Austin Gause Aug 2020

Paleoenvironmental Reconstruction Of Quaternary Saltville, Virginia, Using Ostracode Autecology, Austin Gause

Electronic Theses and Dissertations

The Saltville valley in southwestern Virginia is home to Quaternary localities containing paleontological and archaeological remains. Historically the valley has been mined for salt and the small lakes, ponds and springs along the valley floor have a brackish signature. A preliminary report on the site’s ostracode fauna suggested that the site’s water was not always saline. This study analyzed modern and Quaternary ostracodes to understand the valley’s hydrologic and chemical evolution. Sediments contained primarily freshwater species, including the environmentally sensitive Candona crogmaniana. The presence of Pelocypris tuberculatum and a new Fabaeformiscandona species throughout a vertical section spanning the latest Pleistocene …


Statement Of World Aquatic Scientific Societies On The Need To Take Urgent Action Against Human-Caused Climate Change, Based On Scientific Evidence [Dear Colleague Letter], Scott A. Bonar, Brian R. Murphy, Leanne H. Roulson, Jesse T. Trushenski, Douglas J. Austen, Michael Edward Douglas Jul 2020

Statement Of World Aquatic Scientific Societies On The Need To Take Urgent Action Against Human-Caused Climate Change, Based On Scientific Evidence [Dear Colleague Letter], Scott A. Bonar, Brian R. Murphy, Leanne H. Roulson, Jesse T. Trushenski, Douglas J. Austen, Michael Edward Douglas

United States Fish and Wildlife Service: Publications

Dear Colleague Letter from the American Fisheries Society to fellow scientific societies, July 25, 2020, about the urgent need for responsive collective action to mitigate impending radical climate change. Includes the Statement of World Aquatic Scientific Societies on the Need to Take Urgent Action Against Human-Caused Climate Change, Based on Scientific Evidence, emphasizing the importance of aquatic ecosystems. Includes extensive citations and notes.

"Water is the most important natural resource on Earth as it is vital for life. Aquatic ecosystems, freshwater or marine, provide multiple benefits to human society, such as provisioning of oxygen, food, drinking water, genetic resources; regulation …


A Framework For Aquatic Invasive Species Surveillance Site Selection And Prioritization In The Us Waters Of The Laurentian Great Lakes, Andrew J. Tucker, W. Lindsay Chadderton, Gust Annis, Alisha D. Davidson, Joel Hoffman, Jon Bossenbroek, Stephen Hensler, Michael Hoff, Erika Jensen, Donna R. Kashian, Sarah Lesage, Timothy Strakosh Jul 2020

A Framework For Aquatic Invasive Species Surveillance Site Selection And Prioritization In The Us Waters Of The Laurentian Great Lakes, Andrew J. Tucker, W. Lindsay Chadderton, Gust Annis, Alisha D. Davidson, Joel Hoffman, Jon Bossenbroek, Stephen Hensler, Michael Hoff, Erika Jensen, Donna R. Kashian, Sarah Lesage, Timothy Strakosh

Environmental Science and Geology Faculty Research Publications

Risk-based prioritization for early detection monitoring is of utmost importance to prevent and mitigate invasive species impacts and is especially needed for large ecosystems where management resources are not sufficient to survey all locations susceptible to invasion. In this paper we describe a spatially-explicit and quantitative approach for identifying the highest risk sites for aquatic invasive species (AIS) introduction into the United States’ waters of the Laurentian Great Lakes, a vast inland sea with a surface area of 246,049 square km and a shoreline length of 16,431 km. We compiled data from geospatial metrics available across all of the US …


Projected Surface Water For Fruit And Vegetable Irrigation Under A Changing Climate In The Us, Marty Matlock, Greg Thoma, Kieu Ngoc Le, Eric Cummings, Zach Morgan, Andrew Shaw Jun 2020

Projected Surface Water For Fruit And Vegetable Irrigation Under A Changing Climate In The Us, Marty Matlock, Greg Thoma, Kieu Ngoc Le, Eric Cummings, Zach Morgan, Andrew Shaw

Water Systems

Increasing greenhouse gas concentrations in the atmosphere, resulting in climate impacts, are raising concerns over the hydrologic cycle and its effects upon agricultural productivity. If rainfall patterns change, meeting an increased demand for fruits and vegetables will pose a challenge for domestic production regions in the United States (U.S.). Information on potential water supply scarcity in the current production regions provides decision makers with critical information for risk mitigation for future production. We used a hydrologic balance-based model of historic and future water availability to evaluate risk of available irrigation water to support major fruit and vegetable production the US. …


The Release, Transport, And Utilization Of Phosphorus From Bed-Sediments: A Study Of A Eutrophic Littoral Cove On Beaver Lake In Northwest Arkansas, James A. Mccarty May 2020

The Release, Transport, And Utilization Of Phosphorus From Bed-Sediments: A Study Of A Eutrophic Littoral Cove On Beaver Lake In Northwest Arkansas, James A. Mccarty

Graduate Theses and Dissertations

Eutrophication of surface waters not only impacts the environment but also water treatment processes, the most significant of which is from the effects of algae. During peak algal growth in many southern U.S. reservoirs, inflows that bring nutrients are at an annual minimum, and phosphorus released from bed-sediments is trapped in the hypolimnion. Littoral areas, described as the most productive zone of the lake, may be a possible source of phosphorus that fuels algal growth in the reservoir. I studied an isolated shallow cove in the War Eagle Creek arm of Beaver Lake in Northwest Arkansas to measure, quantify, and …


Climate Change Effects On Volcanoes In The Tropics: A Review Of The Deglaciation Of Antisana And Its Effects On Subsequent Water Streams And Rivers Over 20 Years, Callie C. Rominger Apr 2020

Climate Change Effects On Volcanoes In The Tropics: A Review Of The Deglaciation Of Antisana And Its Effects On Subsequent Water Streams And Rivers Over 20 Years, Callie C. Rominger

Independent Study Project (ISP) Collection

Located in the Northern end of Ecuador lies the stunning glacier of Antisana which attracts many tourists and whose runoff provides a significant amount of water supply for Quito. Climate change is posing threats to many ecosystems world wide but will have a more substantial impact on the volcanoes in the tropics because they do not have a seasonally altered climate. Small changes in the air temperature can have larger impacts on these areas that are adapted to constant temperatures with seasonal precipitation changes. Climate change, in recent years, had caused an increase in the glacial retreat of the Antisana …


Macroinvertebrate Community And Temperature Changes In A Michigan Stream, Nyika Campbell Apr 2020

Macroinvertebrate Community And Temperature Changes In A Michigan Stream, Nyika Campbell

Independent Study Project (ISP) Collection

As the climate warms, global biodiversity is plummeting and extinction rates are rising (Jenkins, 2003). Freshwater ecosystems specifically are experiencing huge losses in diversity (Jenkins, 2003; Ormerod et al., 2010; Collier et al., 2016). Conservation of invertebrates is particularly urgent because they are foundational to the trophic systems in streams and lakes, comprising 95% of all species on earth (Titley et al., 2017), and over 60% of biodiversity in freshwater ecosystems (Collier et al., 2016). Through analysis of both my own field measurements and historical data I seek to gain a preliminary understanding of temperature and macroinvertebrate community changes that …


If Watersheds Spoke: A Condition Analysis Of The Rio Tomebamba Watershed In Southern Ecuador Using Gis Analysis, Lenka G. Doskocil Apr 2020

If Watersheds Spoke: A Condition Analysis Of The Rio Tomebamba Watershed In Southern Ecuador Using Gis Analysis, Lenka G. Doskocil

Independent Study Project (ISP) Collection

Understanding processes and ecological threats occurring at the watershed level scale composes a critical piece of water resource conservation and management. This proves doubly true in areas such as the Ecuadorian highlands where water resources depend heavily on the hydrologic regulation capacities of páramo soils. This study examined watershed condition of the Rio Tomebamba watershed and existing habitat for Metallura baroni and Chibchanomys orcesi, two highly endemic species, within its boundaries. Watershed condition was determined based on a simple index that considered nine indicators of watershed health—converted land, impacted riparian zones, impermeable surfaces, water quality, fluvial habitat condition, riparian vegetation …


Spatial And Temporal Genetic Structure Of Winter-Run Steelhead (Oncorhynchus Mykiss) Returning To The Mad River, California, Steven R. Fong Jan 2020

Spatial And Temporal Genetic Structure Of Winter-Run Steelhead (Oncorhynchus Mykiss) Returning To The Mad River, California, Steven R. Fong

Cal Poly Humboldt theses and projects

Distinct populations of steelhead in the wild are in decline. The propagation of steelhead in hatcheries has been used to boost population numbers for recreational fisheries and for use in conservation. However, hatchery breeding practices of steelhead can result in changes in genetic structure. I investigated the genetic structure of winter-run steelhead (Oncorhynchus mykiss) returning to the Mad River, California, where a hatchery has been used enhance production for recreational fisheries since 1971. Genetic variability in Mad River steelhead was evaluated using 96 single nucleotide polymorphisms (SNPs) among 4203 individuals, including the Mad River and nearby locations, and …


An International Laboratory Comparison Of Dissolved Organic Matter Composition By High Resolution Mass Spectrometry: Are We Getting The Same Answer?, Jeffrey A. Hawkes, Juliana D'Andrilli, Jeffrey N. Agar, Mark P. Barrow, Stephanie M. Berg, Núria Catalán, Hongmei Chen, Rosalie K. Chu, Richard B. Cole, Thorsten Dittmar, Rémy Gavard, Gerd Gleixner, Patrick G. Hatcher, Chen He, Nancy J. Hess, Ryan H.S. Hutchins, Amna Ijaz, Hugh E. Jones, William Kew, Maryam Khaksari, Diana Catalina Palacio Lozano, Jitao Lv, Lynn R. Mazzoleni, Beatriz E. Noriega-Ortega, Helena Osterholz, Nikola Radoman, Christina K. Remucal, Nicholas D. Schmitt, Simeon K. Schum, Quan Shi, Carsten Simon, Gabriel Singer, Rachel L. Sleighter, Aron Stubbins, Mary J. Thomas, Nikola Tolic, Shuzhen Zhang, Phoebe Zito, David C. Podgorski Jan 2020

An International Laboratory Comparison Of Dissolved Organic Matter Composition By High Resolution Mass Spectrometry: Are We Getting The Same Answer?, Jeffrey A. Hawkes, Juliana D'Andrilli, Jeffrey N. Agar, Mark P. Barrow, Stephanie M. Berg, Núria Catalán, Hongmei Chen, Rosalie K. Chu, Richard B. Cole, Thorsten Dittmar, Rémy Gavard, Gerd Gleixner, Patrick G. Hatcher, Chen He, Nancy J. Hess, Ryan H.S. Hutchins, Amna Ijaz, Hugh E. Jones, William Kew, Maryam Khaksari, Diana Catalina Palacio Lozano, Jitao Lv, Lynn R. Mazzoleni, Beatriz E. Noriega-Ortega, Helena Osterholz, Nikola Radoman, Christina K. Remucal, Nicholas D. Schmitt, Simeon K. Schum, Quan Shi, Carsten Simon, Gabriel Singer, Rachel L. Sleighter, Aron Stubbins, Mary J. Thomas, Nikola Tolic, Shuzhen Zhang, Phoebe Zito, David C. Podgorski

Chemistry & Biochemistry Faculty Publications

High-resolution mass spectrometry (HRMS) has become a vital tool for dissolved organic matter (DOM) characterization. The upward trend in HRMS analysis of DOM presents challenges in data comparison and interpretation among laboratories operating instruments with differing performance and user operating conditions. It is therefore essential that the community establishes metric ranges and compositional trends for data comparison with reference samples so that data can be robustly compared among research groups. To this end, four identically prepared DOM samples were each measured by 16 laboratories, using 17 commercially purchased instruments, using positive-ion and negative-ion mode electrospray ionization (ESI) HRMS analyses. The …