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Articles 1 - 28 of 28
Full-Text Articles in Life Sciences
Long Term Monitoring Of Grand Ravines Park Restoration: An Authentic Research Opportunity For Jenison High School Students And Beyond, Karina C. White
Long Term Monitoring Of Grand Ravines Park Restoration: An Authentic Research Opportunity For Jenison High School Students And Beyond, Karina C. White
Culminating Experience Projects
Access to authentic research is limited at the 7-12 science education level. At the same time, many local restoration projects would benefit from, but don’t have access to a long-term system of monitoring. This project seeks to unite those two needs by developing a protocol for 7-12 classrooms to be able to participate in authentic research through long-term monitoring of a local restoration project. The protocol developed in this project was used by Jenison High School students at Grand Ravines Park. Grand Ravines Park is a recently acquired Ottawa County park with a history of anthropogenic disturbances. Shortly after the …
The Impacts Of Road Salt On Water Quality And Phosphorus Dynamics In An Urban Lake, Ellen Foley
The Impacts Of Road Salt On Water Quality And Phosphorus Dynamics In An Urban Lake, Ellen Foley
Masters Theses
Road salt runoff from de-icing applications has notably increased chloride concentrations in lakes throughout north temperate regions of the planet, with negative impacts on freshwater ecosystems. For the past 20 months, I have monitored the water quality of a chloride-impaired lake and associated tributary in Grand Rapids, Michigan. Chloride levels in the deepest part of the lake have reached up to 331 mg/L, above EPA chronic toxicity thresholds. The salt-induced density gradient has prevented the lake from completely mixing during my study period and created persistent hypoxia in the hypolimnion. Total phosphorus (TP) concentrations in the hypolimnion can exceed 7500 …
Using Plot Photographs To Estimate Tundra Vegetation Cover In Northern Alaska, Hana Christoffersen
Using Plot Photographs To Estimate Tundra Vegetation Cover In Northern Alaska, Hana Christoffersen
Masters Theses
Plot photography can provide a quick, robust method to measure vegetation, especially in polar environments where logistics can be expensive and challenging. The success and widespread adoption of plot photography in the Arctic hinges on the accuracy of image analysis and data product interpretation. The relative cover of eight vegetation classes was estimated using a point frame and digital camera across thirty, 1-m2 plots at Utqiaġvik, Alaska from 2012 to 2021. Geographic object-based image analysis (GEOBIA) was applied to generate objects and classify the three band (red, green, blue) images. Machine learning classifiers (random forest, gradient boosted model, classification …
The Spatial Ecology And Habitat Selection Of A Spotted Turtle (Clemmys Guttata) Population In Southwest Michigan, Michela Coury
The Spatial Ecology And Habitat Selection Of A Spotted Turtle (Clemmys Guttata) Population In Southwest Michigan, Michela Coury
Masters Theses
Turtles are arguably the most threatened group of vertebrates on the planet. Anthropogenic influences such as habitat loss and fragmentation, road mortality, subsidized predators, climate change, and illegal collection have contributed to their global decline. Understanding which isolated populations of turtles are viable despite these synergistic threats is crucial for making conservation and management decisions. In Michigan, the spotted turtle (Clemmys guttata) is a threatened species subjected to many negative anthropogenic influences that accelerate its rapid population decline. In order to properly sustain their populations, the goal of my research was to investigate relevant factors that help us …
Assessing The Short-Term Effects Of Translocation On Freshwater Mussels: Is Habitat Or Water Quality More Important?, Joshua D. Arnold
Assessing The Short-Term Effects Of Translocation On Freshwater Mussels: Is Habitat Or Water Quality More Important?, Joshua D. Arnold
Masters Theses
Freshwater mussels (Order: Unionida) are very important to the function of aquatic ecosystems and are typically indicators of good water quality. They provide a valuable link between the water column and the benthic substrate in which they live and are a valuable food resource for many species of animals. However, most species native to North America are currently threatened with extinction, to the point that more than 70% of native freshwater mussels are listed as either threatened or endangered at the state or federal level. The cause of this decline can be attributed to historical over exploitation, habitat alteration, and …
Analysis Of Seasonal Changes In Thermal Stress Resilience And Innate Immunity In The Temperate Coral, Astrangia Poculata, From Future Climate Impacts, Tyler Eugene Harman
Analysis Of Seasonal Changes In Thermal Stress Resilience And Innate Immunity In The Temperate Coral, Astrangia Poculata, From Future Climate Impacts, Tyler Eugene Harman
Masters Theses
Over the years, global warming has had a devastating effect on coral reef ecosystems. Anthropogenic influences have caused significant increases in greenhouse gases, with a subsequent increase in solar radiation held within Earth’s atmosphere leading to increasing global temperatures. The increasing temperatures from concurrent increases in greenhouse gases impact fragile marine ecosystems such as coral reefs, which require particular environmental parameters such as temperature in order to survive and maintain a diverse ecosystem in which many marine species rely on. These increases in temperature exacerbate phenomena such as bleaching events and coral disease, drastically impacting coral on a global scale …
Competitive Interactions: Spatial And Temporal Niche Partitioning Between Brook And Brown Trout In Southwest Michigan, Frederick J. Glassen
Competitive Interactions: Spatial And Temporal Niche Partitioning Between Brook And Brown Trout In Southwest Michigan, Frederick J. Glassen
Masters Theses
Niche diet partitioning between Brook Trout and Brown Trout were studied in two southwestern Michigan, USA streams, one dominated by Brook Trout, the other with both Brook and Brown Trout. Brook Trout are endemic to eastern North America and have been introduced throughout the world for sport fishing. Brown Trout were first introduced to Michigan in 1883 using a genetic strain from Germany. Stomach contents were collected from a population of Brook Trout in the absence of Brown Trout in Frost Creek, while the other population was in potential competition with Brown Trout in Cedar Creek. Absent Brown Trout, Brook …
Bloom Or Bust: Search For Phytoplankton Community Drivers Using Long-Term Time-Series Observations And Field Measurements In A Model Great Lakes Estuary, Jasmine Mancuso
Bloom Or Bust: Search For Phytoplankton Community Drivers Using Long-Term Time-Series Observations And Field Measurements In A Model Great Lakes Estuary, Jasmine Mancuso
Masters Theses
As sentinels of climate change and other anthropogenic effects, freshwater lakes are experiencing ecosystem disruptions at every level of the food web, beginning with the phytoplankton. One of the major threats to waterbodies around the world are cyanobacterial harmful algal blooms (HABs) resulting from anthropogenic eutrophication and exacerbated by climate change. Muskegon Lake, a drowned river mouth Great Lakes estuary on the east coast of Lake Michigan, is no exception and was declared an Area of Concern by the EPA in 1987 with nuisance algal blooms cited as a beneficial use impairment. Using long-term data and additional 2019 sampling, we …
Snowshoe Hare (Lepus Americanus) Abundance In Relation To Habitat And Predator Assemblage Across The Apostle Islands, Jarod Reibel
Snowshoe Hare (Lepus Americanus) Abundance In Relation To Habitat And Predator Assemblage Across The Apostle Islands, Jarod Reibel
Masters Theses
Snowshoe hares (Lepus americanus) are a climate sensitive species that have a southern range boundary moving northward. Snowshoe hares are found on the Apostle Islands, Wisconsin which are near their southern boundary and differ by island in vegetative and carnivore communities. The archipelago serves as a natural laboratory to assess how top-down and bottomup forces interact and impact snowshoe hare populations. The objectives of this study were to determine the influence of vegetative characteristics, specifically visual obstruction, and the presence of predators on snowshoe hare abundances across the Apostle Islands. We conducted fecal pellet surveys to estimate hare abundance, measured …
Impacts Of Shoreline Restoration And Source Of Nutrient Enrichment On Macrophytes And Epiphytic Algal Communities, Paige Marie Kleindl
Impacts Of Shoreline Restoration And Source Of Nutrient Enrichment On Macrophytes And Epiphytic Algal Communities, Paige Marie Kleindl
Masters Theses
Macrophytes and their epiphytic algal communities are integral for optimizing littoral ecosystem functioning in lakes. Epiphytic algae’s placement on the plant’s surface can reduce light and nutrient availability (i.e., nitrogen and phosphorus) for the host macrophyte. Macrophyte and epiphytic algal proximity complicates these primary producer group interactions and responses to bioavailable nutrients in the water column or porewater. For example, epiphytic algae may have a competitive advantage over surface water nutrients compared to macrophytes, which may have a competitive advantage over porewater nutrients via root systems.
Muskegon Lake’s industrial history and designation as an Area of Concern prompted shoreline restoration, …
The Implementation Of Qpcr Beach Monitoring Methods: Analysis Of A Multi-Lab Validation Study And The Role Of Environmental Parameters On A Comparison Of Colilert And Qpcr Methods, Molly J. Lane
Masters Theses
Public beaches are routinely tested for potentially pathogenic bacteria to protect beachgoers from possible illness. An EPA approved method, Colilert™, used for testing E. coli in recreational water requires 18 – 22 hours before a result is reported but, recreators have already contacted unsafe water before the beach is closed. My study focused on a U.S. EPA proposed qPCR method (Draft Method C) to quantify E. coli in recreational waters that can provide same-day results. In Chapter 2, I examined the calibration procedure used to validate Draft Method C and compared standard curve intercept and slope estimates calculated with a …
Habitat Use Of The Climate-Sensitive Snowshoe Hare (Lepus Americanus) In The Manistee National Forest In Michigan’S Lower Peninsula, Spencer D. West
Habitat Use Of The Climate-Sensitive Snowshoe Hare (Lepus Americanus) In The Manistee National Forest In Michigan’S Lower Peninsula, Spencer D. West
Masters Theses
Snowshoe hares (Lepus americanus) are a wide-ranging lagomorph that are important forest herbivores and a popular game species throughout their range. Across the southern boundary of their geographic range, snowshoe hares are experiencing population declines and possible extirpation due to increased predation pressure driven by climate change induced camouflage mismatch, competition for forage, degraded and fragmented habitat. One method of reversing the negative trends in snowshoe hare distribution is to increase and improve available hare habitat. A specific habitat analysis for local regions will most effectively advise managers how to target habitat management. I radio-collared 11 snowshoe hares in the …
Alternative Reproductive Tactics In Lake Michigan Populations Of Invasive Round Goby (Neogobius Melanostomus): How Fish Increase Fitness By Doing Less, Alex Florian, Steve Smit
Alternative Reproductive Tactics In Lake Michigan Populations Of Invasive Round Goby (Neogobius Melanostomus): How Fish Increase Fitness By Doing Less, Alex Florian, Steve Smit
Student Summer Scholars Manuscripts
Understanding the reproductive biology of invasive species is an important step in managing populations. Yet, little is known about the reproductive strategies of invasive round goby (Neogobius melanostomus) in Lake Michigan. For round goby, fertilization occurs externally in nests guarded by large “paternal” males. However, some males pursue alternative reproductive tactics (ARTs), where males sneak into a larger male’s nest and fertilize a portion of the eggs, these males are called “sneakers”. We investigated if the proportion of ARTs varies between sites and how that affects population dynamics of round goby. We caught 264 fish from 4 lakes along Eastern …
Measuring Streambank Erosion: A Comparison Of Erosion Pins, Total Station, And Terrestrial Laser Scanner, Daniel T. L. Myers, Richard R. Rediske, James N. Mcnair
Measuring Streambank Erosion: A Comparison Of Erosion Pins, Total Station, And Terrestrial Laser Scanner, Daniel T. L. Myers, Richard R. Rediske, James N. Mcnair
Funded Articles
Streambank erosion is diffcult to quantify; models and field methods are needed to assess this important sediment source to streams. Our objectives were to (1) evaluate and compare three techniques for quantifying streambank erosion: erosion pins, total station, and laser scanning, (2) spatially assess streambank erosion rates in the Indian Mill Creek watershed of Michigan, USA, and (3) relate results with modeling of nonpoint source pollution. We found large absolute and relative errors between the different measurement techniques. However, we were unable to determine any statistically significant differences between techniques and only observed a correlation between total station and laser …
Dynamic Carbon Cycling In Muskegon Lake – A Great Lakes Estuary, Katie Lynn Knapp
Dynamic Carbon Cycling In Muskegon Lake – A Great Lakes Estuary, Katie Lynn Knapp
Masters Theses
Ecosystem metabolism is the coupling of carbon and oxygen through photosynthesis and respiration. Gross primary production (GPP) is the carbon fixation by photosynthesis, ecosystem respiration (R) is carbon remineralization by bacterial and plankton respiration, and net ecosystem production (NEP) is the balance. Metabolism estimates determine if ecosystem is a sink or source of carbon to the atmosphere. When a lake has a positive NEP, or the GPP:R ratio is greater than 1, it is considered autotrophic and less carbon is being lost to the atmosphere than taken in, whereas if NEP is negative (GPP:R-1d-1, respectively and the BOD …
Habitat Use And Tributary Occupancy Of The Threatened River Redhorse (Moxostoma Carinatum) In The Grand River, Mi, Usa., Nicholas Michael Preville
Habitat Use And Tributary Occupancy Of The Threatened River Redhorse (Moxostoma Carinatum) In The Grand River, Mi, Usa., Nicholas Michael Preville
Masters Theses
The resiliency of our aquatic ecosystems hinges on our ability to protect the native species that reside within them. The river redhorse (Moxostoma carinatum) is one such example and populations have become low enough to warrant listing by the State of Michigan. Causes of decline include overfishing, habitat alteration, and lack of knowledge of basic life-history attributes including their use of non-spawning habitat and spawning locations. In order to understand the river redhorse’s habitat use we implanted 15 individuals with radio transmitters and tracked their locations over the course of a summer. Tagged river redhorse were found to …
An Assessment Of Periphyton Communities In Five Upper Peninsula Streams, Mi, Aaron Jeffrey Christiansen
An Assessment Of Periphyton Communities In Five Upper Peninsula Streams, Mi, Aaron Jeffrey Christiansen
Masters Theses
This project quantified lotic periphyton community change from May 2018-October 2018 in five, first and second-order Lake Superior tributary streams. Using periphyton communities, land use, geology, and abiotic factors pertinent to stream ecosystems we evaluated periphyton community succession. Using periphytometers, periphyton communities were collected and identified monthly to quantify community succession. Total phosphorus and total Kjeldahl nitrogen were measured monthly during the study. Depth, velocity, specific conductivity, and canopy cover were measured to quantify some of the physical factors within the streams. Nonmetric multidimensional scaling analysis indicated that the periphyton communities were similar between streams (ADONIS p-value =0.73) but was …
Using Landscape Genetics To Understand Connectivity Of An Island Population Of Eastern Massasauga Rattlesnakes (Sistrurus Catenatus), Nathan Kudla
Masters Theses
Populations that experience low levels of gene flow commonly display increased levels of inbreeding, lower genetic diversity, and reduced adaptive potential. Landscape genetics allows for spatial and genetic information to be analyzed simultaneously to better understand how the landscape influences gene flow. The eastern massasauga rattlesnake (Sistrurus catenatus) is a federally threatened viper found in wetlands throughout the Great Lakes region. Many remaining populations are small and isolated due primarily to habitat loss. Atypical from a range-wide perspective, eastern massasaugas on Bois Blanc Island (BBI), Michigan live in a relatively undisturbed landscape with a potential for high connectivity …
The Association Between Dietary Niche Variation In Rodents And Climate Change Across The Paleocene-Eocene Thermal Maximum, Hannah K. Vermeer
The Association Between Dietary Niche Variation In Rodents And Climate Change Across The Paleocene-Eocene Thermal Maximum, Hannah K. Vermeer
Masters Theses
Mammalian teeth play a crucial role in food acquisition and breakdown and are therefore closely tied to dietary niche. This study reconstructed the diet of early Paleogene paramyid rodents across the Paleocene-Eocene Thermal Maximum (PETM) climatic event in an effort to understand the role of climate in mammalian dietary niche change. Dietary niches were quantified using three dental topographic measures: Dirichlet normal energy, relief index, and orientation patch count rotated. A Kruskal-Wallis test was conducted over eight time periods to determine if each of the dental topographic measures (i.e., diet) varied over time. Regression analysis of these measures with climatic …
Evaluating Remote Site Incubators To Support Restoration Of Arctic Grayling In Michigan, Alan J. Mock
Evaluating Remote Site Incubators To Support Restoration Of Arctic Grayling In Michigan, Alan J. Mock
Masters Theses
Remote site incubators (RSIs) have been used to rear salmonid fish eggs along streams in the Pacific Northwest since the 1980s. Recently, the successful use of RSIs for Arctic Grayling Thymallus arcticus restoration in Montana has sparked a renewed interest to reestablish the species in Michigan. To support future reintroduction efforts of Arctic Grayling in Michigan, I evaluated RSIs in three Michigan streams during 2018 and 2019 using Rainbow Trout Oncorhynchus mykiss eggs (as surrogates for Arctic Grayling). My objectives were to: (1) compare hatching success between two different RSI designs (19-L vs. 265-L RSIs), and (2) test whether the …
Ecological Niche Modeling And Local Knowledge Predict New Populations Of Gymnocladus Assamicus A Critically Endangered Tree Species, Shaily Menon, Baharul I. Choudhury, M. Latif Khan, A. Townsend Peterson
Ecological Niche Modeling And Local Knowledge Predict New Populations Of Gymnocladus Assamicus A Critically Endangered Tree Species, Shaily Menon, Baharul I. Choudhury, M. Latif Khan, A. Townsend Peterson
Peer Reviewed Publications
Gymnocladus assamicus is a critically endangered tree species endemic to northeastern India. Local inhabitants traditionally used this species for a variety of purposes. However, rapid population declines led to the species being considered extinct, until fieldwork in 2004 to 2007 identified 14 discrete populations of 1 to 7 trees each. To overcome constraints on field surveys imposed by the region’s remoteness and rugged terrain, we targeted areas of further field inventories by estimating the potential distribution of the species. Ecological niche modeling enabled us to identify 26 sites which the model predicted to be highly suitable for the species’ occurrence. …
Projected Climate Change Effects On Nuthatch Distribution And Diversity Across Asia, Shaily Menon, M. Zafar-Ul Islam, A. Townsend Peterson
Projected Climate Change Effects On Nuthatch Distribution And Diversity Across Asia, Shaily Menon, M. Zafar-Ul Islam, A. Townsend Peterson
Peer Reviewed Publications
We used ecological niche modeling approaches to explore climate change implications for one family of birds, the Sittidae, in Asia. Quantitative niche models based on present-day distributions for each of 13 species were projected onto future climate change scenarios. Species’ potential distributional areas tended to be predicted to retract along their fringes, and at lower elevations along mountain ranges. As observed in other studies, montane systems were relatively more robust to the horizontal effects of climate change on species’ distributions compared to flatland systems, so range contractions were focused in Southeast Asia and peninsular India.
Sediment Remediation Impacts On Macroinvertebrate Community Structure: Assessing The Success Of Urban Stream Restoration, Laurie Beth Nederveld
Sediment Remediation Impacts On Macroinvertebrate Community Structure: Assessing The Success Of Urban Stream Restoration, Laurie Beth Nederveld
Masters Theses
Land use practices altering the natural landscape have resulted in the widespread degradation of stream ecosystems and the need for urban stream restorations. While a number of studies have evaluated the success of these stream restoration efforts, few have assessed the recovery of macroinvertebrate communities following the remediation of contaminated sediments. The purpose of my study was to evaluate the impact of sediment remediation activities on macroinvertebate abundance, diversity, and richness to determine the success of stream restoration in Ruddiman Creek, a small stream in the Muskegon Lake watershed. During my investigation, macroinvertebrate samples were collected from all available habitat …
Fundamentals For Using Geographic Information Science To Measure The Effectiveness Of Land Conservation Projects, Robert G. Pontius Jr., Shaily Menon, Joseph Duncan, Shalini Gupta
Fundamentals For Using Geographic Information Science To Measure The Effectiveness Of Land Conservation Projects, Robert G. Pontius Jr., Shaily Menon, Joseph Duncan, Shalini Gupta
Other Scholarly Publications
Some humans spend a tremendous amount of effort to change landscapes from a “natural” state to a “developed” state for a variety of desirable economic uses, such as urban, agriculture, transportation, and mining. Others spend a tremendous amount of effort to prevent such development in order to conserve the landscapes for a variety of important environmental uses, such as biodiversity maintenance, carbon storage, water filtration, and landslide prevention. It would be efficient in theory if a society were to focus its development efforts at locations that give the largest economic utility per area developed, and to focus its conservation efforts …
Aquatic Ecosystem Response To Storm Water Abatement Measures In The Ravines Of The Gvsu Allendale Campus: Establishment Of Base-Line Biological Condition, Eric Snyder, Jason Nelson, Jason Drogowski, Michelle Harju
Aquatic Ecosystem Response To Storm Water Abatement Measures In The Ravines Of The Gvsu Allendale Campus: Establishment Of Base-Line Biological Condition, Eric Snyder, Jason Nelson, Jason Drogowski, Michelle Harju
Technical Reports
The ravine tributary streams surrounding Grand Valley State Universities Allendale campus represent unique and understudied ecosystems, worthy of significant restoration efforts and of long-lasting protection. They are variously affected by storm water runoff, representing a spectrum from severely impacted to relatively pristine. Quantitative macroinvertebrate samples taken from six streams in late June 2007, indicated that insect diversity was positively correlated to ammonium (p=0.057), while total abundance was negatively correlated to phosphate and chlorophyll-a concentration (n.s.). In addition, phosphate, nitrate, sulfate and iron concentrations were elevated in streams that experience significant storm-water runoff and these streams also tended to have …
Hydrologic Events And Water Quality In The Pigeon River, Ottawa County, Michigan, Neil W. Macdonald, Richard R. Rediske, Jonathan E. Van Denend
Hydrologic Events And Water Quality In The Pigeon River, Ottawa County, Michigan, Neil W. Macdonald, Richard R. Rediske, Jonathan E. Van Denend
Peer Reviewed Publications
The Pigeon River drains a 16,765-ha agricultural watershed in western Ottawa County, Michigan and discharges into south-central Lake Michigan. Extensive areas of wetlands in the upper watershed were drained in the 1920s, causing significantly altered hydrology characteristics by flashy discharges during storms and periods of snowmelt. We studied stream chemistry and hydrology for a four-year period between September, 1996, and October, 2000, to determine water quality status, to estimate annual nutrient exports, and to evaluate the effects of different seasonal flow types. Results of our study confirmed that the upper reaches of the Pigeon River experience chronically degraded water quality, …
Deforestation In The Tropics: Reconciling Disparities In Estimates For India, Shaily Menon, Kamaljit S. Bawa
Deforestation In The Tropics: Reconciling Disparities In Estimates For India, Shaily Menon, Kamaljit S. Bawa
Peer Reviewed Publications
Here we examine recent disparate estimates of deforestation obtained for India. We discuss the sources of disparity and the implications of inaccurate estimates and suggest ways in which future attempts at estimating deforestation might reconcile the disparity. Despite the importance of deforestation and its consequences, no attempt has been made to reconcile the different estimates obtained for India.
Environmental Stress Effects On Vigor, Mortality, And Growth In Northern Hardwood Forests Along A Pollution-Climate Gradient, Neil W. Macdonald, John A. Witter, David R. Reed, Andrew J. Burton, Kurt S. Pregitzer, Hal O. Liechty
Environmental Stress Effects On Vigor, Mortality, And Growth In Northern Hardwood Forests Along A Pollution-Climate Gradient, Neil W. Macdonald, John A. Witter, David R. Reed, Andrew J. Burton, Kurt S. Pregitzer, Hal O. Liechty
Peer Reviewed Publications
Concern exists over the effects of interacting environmental stresses on the ecological integrity of temperate forests. Coincidence of sensitivity to drought, increasing occurrence of defoliation, and elevated pollutant deposition has produced speculation that northern hardwood forests may be susceptible to the increased climatic stresses projected for the Great Lakes region. The objective of our study was to examine relationships among environmental stress factors, vigor, mortality, and growth in northern hardwood forests located along a pollution-climate gradient in the Great Lakes region. Between 1987 and 1993, we quantified climatic variables, pollutant deposition, insect defoliation, and tree vigor and growth at five …