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Articles 1 - 30 of 13187

Full-Text Articles in Ecology and Evolutionary Biology

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

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 ...


Understanding Plant Secondary Metabolites; Above And Below Ground, Andrea K. Clemensen Aug 2018

Understanding Plant Secondary Metabolites; Above And Below Ground, Andrea K. Clemensen

All Graduate Theses and Dissertations

Plants naturally produce primary and secondary metabolites. Primary metabolites are directly involved with plant growth and metabolic function. Plant secondary metabolites (PSM) were once thought of as metabolic waste products, and more recently viewed as toxins to herbivores. However, ongoing research shows that PSM are beneficial to herbivores at low doses, and PSM aid plants by attracting pollinators, recovering from injury, protecting from ultraviolet radiation, increasing drought tolerance, and aid in defense against pathogens, diseases, and herbivores. Plant secondary metabolites also influence soil nutrient cycling, and can increase the sustainability of agroecosystems. Endophyte-infected tall fescue (Festuca arundinacea Schreb.) , which contains ...


Using Anthropogenic Risks To Inform Salmonid Conservation At The Landscape Scale, Andrew W. Witt Aug 2018

Using Anthropogenic Risks To Inform Salmonid Conservation At The Landscape Scale, Andrew W. Witt

All Graduate Theses and Dissertations

The expansion and industrialization of humanity has caused many unforeseen consequences to the natural world. Due to the importance of freshwater for people, rivers have been particularly altered to meet human needs, often at the expense of the natural world. Supplying water for farms, industries, and cities has reshaped the natural state of rivers by altering river paths, chemistry, and species compositions. These changes have harmed many species that prospered before widespread human alterations, including the native trout and salmon of western North America. As human populations continue to grow, new threats will surface for rivers, and the trout and ...


A New Species Of Vaejovis From The Patagonia Mountains, Southern Arizona (Scorpiones: Vaejovidae), Richard F. Ayrey Jun 2018

A New Species Of Vaejovis From The Patagonia Mountains, Southern Arizona (Scorpiones: Vaejovidae), Richard F. Ayrey

Euscorpius

A new scorpion species, Vaejovis patagonia sp. nov. is described and placed in the “vorhiesi” group. This small, dark brown species is found near Patagonia, Arizona. It is geographically closest to V. troupi Ayrey & Soleglad, V. grahami Ayrey & Soleglad and V. vorhiesi Stahnke. Those three species are found in a triangle surrounding the Patagonia Mountains, the locality of Vaejovis patagonia. The pedipalp fixed finger has 5 ID denticles and the movable finger has 6, like most, but not all, of the other southern Arizona Vaejovis. Carapace of female is shorter than metasomal segment V.


The Genera Butheolus Simon, 1882 And Xenobuthus Gen. Nov. (Scorpiones: Buthidae) In Oman, Graeme Lowe Jun 2018

The Genera Butheolus Simon, 1882 And Xenobuthus Gen. Nov. (Scorpiones: Buthidae) In Oman, Graeme Lowe

Euscorpius

The genus Butheolus Simon, 1882 is revised based on new material from Dhofar Province in Oman. B. gallagheri Vachon, 1980 is redescribed, and a related new species, B. harrisoni sp. n., is also described. The species B. anthracinus (Pocock, 1895) is redescribed and moved to a new genus Xenobuthus gen. n., that is differentiated from Butheolus by size, pedipalp finger dentition, setation, granulation and hemispermatophore structure, and a related new species, X. xanthus sp. n., is also described. Revised diagnoses are provided for the genus Butheolus, and for the species B. thalassinus Simon, 1882, and B. villosus Hendrixson, 2006, a ...


The Influence Of Dose Of A Plant-Derived Volatile Cue On Arabidopsis Thaliana Resistance Against Insect Herbivores, Sarah Bissmeyer, Grace Freundlich, Christopher Frost Jun 2018

The Influence Of Dose Of A Plant-Derived Volatile Cue On Arabidopsis Thaliana Resistance Against Insect Herbivores, Sarah Bissmeyer, Grace Freundlich, Christopher Frost

Kentucky Journal of Undergraduate Scholarship

Green leaf volatiles (GLVs) are plant-derived volatile organic compounds (VOCs) known to affect plant-plant communication. Specifically, GLVs can facilitate “priming”, whereby plants initiate a faster and stronger defensive response to a subsequent stress. The stress-induced GLV cis-3-hexenyl acetate (z3HAC) is a known priming cue, yet whether the concentration of the z3HAC affects plant defenses is unknown. Here, we tested the hypothesis that z3HAC concentration of would influence Arabidopsis thaliana resistance against a specialist (Trichoplusia ni) and generalist (Spodoptera exigua) herbivore. Our z3HAC treatments ranged from 0-100 ng/hr, which spanned the range of recorded natural ...


Arabidopsis Thaliana Ei-5: Minor Vein Architecture Adjustment Compensates For Low Vein Density In Support Of Photosynthesis, Jared J. Stewart, Stephanie K. Polutchko, Barbara Demmig-Adams, William W. Adams Iii Jun 2018

Arabidopsis Thaliana Ei-5: Minor Vein Architecture Adjustment Compensates For Low Vein Density In Support Of Photosynthesis, Jared J. Stewart, Stephanie K. Polutchko, Barbara Demmig-Adams, William W. Adams Iii

University Libraries Open Access Fund Supported Publications

An Arabidopsis thaliana accession with naturally low vein density, Eifel-5 (Ei-5), was compared to Columbia-0 (Col-0) with respect to rosette growth, foliar vein architecture, photosynthesis, and transpiration. In addition to having to a lower vein density, Ei-5 grew more slowly, with significantly lower rates of rosette expansion, but had similar capacities for photosynthetic oxygen evolution on a leaf area basis compared to Col-0. The individual foliar minor veins were larger in Ei-5, with a greater number of vascular cells per vein, compared to Col-0. This compensation for low vein density resulted in similar values for the product of vein density ...


Integrating Species Traits Into Species Pools, Marko J. Spasojevic, Christopher P. Catano, Joseph A. Lamanna Jun 2018

Integrating Species Traits Into Species Pools, Marko J. Spasojevic, Christopher P. Catano, Joseph A. Lamanna

Biology Faculty Publications & Presentations

Despite decades of research on the species‐pool concept and the recent explosion of interest in trait‐based frameworks in ecology and biogeography, surprisingly little is known about how spatial and temporal changes in species‐pool functional diversity (SPFD) influence biodiversity and the processes underlying community assembly. Current trait‐based frameworks focus primarily on community assembly from a static regional species pool, without considering how spatial or temporal variation in SPFD alters the relative importance of deterministic and stochastic assembly processes. Likewise, species‐pool concepts primarily focus on how the number of species in the species pool influences local biodiversity ...


Predicting Critical Transitions In Spatially Distributed Populations With Cubical Homology, Laura Storch, Sarah Day May 2018

Predicting Critical Transitions In Spatially Distributed Populations With Cubical Homology, Laura Storch, Sarah Day

Biology and Medicine Through Mathematics Conference

No abstract provided.


The Role Of Outcome Preferences In Optimizing Heterogenous Disease Control Strategies., Evan Milliken May 2018

The Role Of Outcome Preferences In Optimizing Heterogenous Disease Control Strategies., Evan Milliken

Biology and Medicine Through Mathematics Conference

No abstract provided.


Population Genetics And Bumble Bee Conservation: Saving Species By Thinking Small, Cady Greenslit May 2018

Population Genetics And Bumble Bee Conservation: Saving Species By Thinking Small, Cady Greenslit

Lawrence University Honors Projects

Pollinators have experienced a severe decline over the last few decades, and this includes bumble bee populations (g. Bombus). Bumble bees are important native pollinators, and here I investigate the health of local populations with molecular tools. The field of conservation genetics has created useful methodology for investigating the health and informing management strategies of threatened populations. This work investigates and describes the applications of population genetics, which uses span across the board. These applications are then brought back into the context of bumble bee conservation, and how they fit into the experimental plan I originally designed. I designed an ...


Functions Of Ecosystems: Stream Metabolism As An Efficient And Effective Means To Gage The Health And Understand The Interworking Of Urban Streams In A Watershed Of Rock Island, Il, Ryan Johnson, Dr. Kevin Geedey May 2018

Functions Of Ecosystems: Stream Metabolism As An Efficient And Effective Means To Gage The Health And Understand The Interworking Of Urban Streams In A Watershed Of Rock Island, Il, Ryan Johnson, Dr. Kevin Geedey

Celebration of Learning

Stream metabolism is a critical functional measure of stream health that integrates physical parameters like slope and discharge, with ecosystem functions like photosynthesis and respiration. Stream metabolism is widely studied; however, urban stream metabolism remains poorly understood. Stream metabolism was measured for five streams ranging from 1st to 5th orders from October 11th to October 18th 2017 and four streams ranging from 1st to 4th order from October 22nd to 25th 2017 located within an approximately 9.3 square kilometer watershed of Rock Island, IL that has an urban to suburban type ...


A Quantitative Analysis Of The Effects Of Urbanization, Mesophication And Prescribed Burns On Oak Woodlands In The Chicago Metropolitan Area, Chad Populorum May 2018

A Quantitative Analysis Of The Effects Of Urbanization, Mesophication And Prescribed Burns On Oak Woodlands In The Chicago Metropolitan Area, Chad Populorum

Celebration of Learning

Urban expansion has had devastating impacts on forest ecosystems, especially within the past century. Human attempts to dominate nature have diminished natural disturbance regimes, which have maintained the biodiversity and historic composition of these ecosystems. Fires have been a prominent force in maintaining the structure of oak, hickory and other heliophytic (sun loving and fire-adapted) forest systems. Human induced fire suppression has led to mesophication across North America. Mesophication is the transition from drier conditions with open canopies to wetter conditions with closed canopies. These new conditions decrease the survival rates of these important species and begin to favor mesophytic ...


Effect Of Adult Chemical Cues On Molting Of Fiddler Crab Megalopae In Low Salinity Seawater, Sydney Rilum May 2018

Effect Of Adult Chemical Cues On Molting Of Fiddler Crab Megalopae In Low Salinity Seawater, Sydney Rilum

Undergraduate Honors Theses

Three species of fiddler crabs, Uca minax, U. pugnax, and U. pugilator, are commonly found in estuaries along the Atlantic coast, each with distinct adult habitats differing in salinity and sediment grain size. Prior research has found evidence for larvae exhibiting selective settlement; however, the degree to which and the method by which they choose their species-appropriate habitat to settle in is still unknown. Additionally, a recent study determined that chemical cues from adult crabs stimulate molting in field-caught fiddler crab megalopae, as previously determined in lab-reared megalopae; however, in 35 ppt seawater, few U. minax molted. This study tested ...


Radical Social Ecology As Deep Pragmatism: A Call To The Abolition Of Systemic Dissonance And The Minimization Of Entropic Chaos, Arielle Brender May 2018

Radical Social Ecology As Deep Pragmatism: A Call To The Abolition Of Systemic Dissonance And The Minimization Of Entropic Chaos, Arielle Brender

Student Theses 2015-Present

This paper aims to shed light on the dissonance caused by the superimposition of Dominant Human Systems on Natural Systems. I highlight the synthetic nature of Dominant Human Systems as egoic and linguistic phenomenon manufactured by a mere portion of the human population, which renders them inherently oppressive unto peoples and landscapes whose wisdom were barred from the design process. In pursuing a radical pragmatic approach to mending the simultaneous oppression and destruction of the human being and the earth, I highlight the necessity of minimizing entropic chaos caused by excess energy expenditure, an essential feature of systems that aim ...


‘Preferred’ Stimulus Of A Whole Model Visual System, Olivier Penacchio, Julie M. Harris May 2018

‘Preferred’ Stimulus Of A Whole Model Visual System, Olivier Penacchio, Julie M. Harris

MODVIS Workshop

No abstract provided.


The Distribution, Abundance, And Gut Microbiome Of Ribbed Mussel, Geukensia Demissa, Across Natural And Restored Salt Marshes In Jamaica Bay, New York, Bethany Freynk May 2018

The Distribution, Abundance, And Gut Microbiome Of Ribbed Mussel, Geukensia Demissa, Across Natural And Restored Salt Marshes In Jamaica Bay, New York, Bethany Freynk

Student Theses

Coastal wetlands perform valuable functions by protecting shorelines from floodwaters and storm surges, providing habitats for marine species, and improving local water quality. Unfortunately, over half of the area of global wetlands has been lost over the past century. Locally, in Jamaica Bay (Queens, NY), loss of wetlands has exceeded 98%. Restoration of Jamaica Bay marshes began in 2003. Ribbed mussels, Geukensia demissa, live symbiotically with marsh plants and have been shown to stabilize sediments and provide organic nutrients that enhance marsh plant growth. Mussels are suspension feeders, which collect algae from seawater and deposit organic matter in marsh sediments ...


Secrets Of A Rare Bird: Breeding Behavior Of The Gray-Breasted Flycatcher (Lathrotriccus Griseipectus) In Ecuador, William Harris Kirkpatrick May 2018

Secrets Of A Rare Bird: Breeding Behavior Of The Gray-Breasted Flycatcher (Lathrotriccus Griseipectus) In Ecuador, William Harris Kirkpatrick

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

The Tumbesian region of southwestern Ecuador and northwestern Peru is home to a large number of endemic bird species. Many of these species are threatened with extinction, and little is known about their basic biology. Thus, information regarding natural history of species in the region is needed to guide conservation management. We studied the reproductive biology of the Gray-breasted Flycatcher, Lathrotriccus griseipectus, a small Tyrannid that lives in the Tumbesian region. Due to habitat destruction, the range size of L. griseipectus has dwindled and the species is now listed as Vulnerable on the IUCN Red List. We used a mounted ...


Seasonal Variation In Physiology Challenges The Notion Of Chimpanzees (Pan Troglodytes Verus) As A Forest-Adapted Species, Erin G. Wessling, Tobias Deschner, Roger Mundry, Jill D. Pruetz, Roman M. Wittig, Hjalmar S. Kühl May 2018

Seasonal Variation In Physiology Challenges The Notion Of Chimpanzees (Pan Troglodytes Verus) As A Forest-Adapted Species, Erin G. Wessling, Tobias Deschner, Roger Mundry, Jill D. Pruetz, Roman M. Wittig, Hjalmar S. Kühl

World Languages and Cultures Publications

Savanna-mosaic habitats are thought to represent exceptional circumstances for chimpanzees (Pan troglodytes), and owing to the virtues of their habitat as well as peripheral biogeographic location, they are often regarded as marginal to the chimpanzee ecological niche. If these habitats are marginal, then we should expect that chimpanzees living in these habitats demonstrate physiological consequences of the extremity of this environment. We therefore compared seasonal variation in physiological responses to climatic and ecological factors in chimpanzees inhabiting Fongoli, a savanna-mosaic habitat at the margins of the chimpanzee range with chimpanzees from Taï National Park, a lowland rainforest centrally located within ...


Population Structure, Demographic History, And Environmental Niche Of The Sand Fly Disease Vector Lutzomyia Shannoni (Dyar) (Diptera: Psychodidae) In The U.S., Mexico, And Colombia, Matthew E. Wolkoff May 2018

Population Structure, Demographic History, And Environmental Niche Of The Sand Fly Disease Vector Lutzomyia Shannoni (Dyar) (Diptera: Psychodidae) In The U.S., Mexico, And Colombia, Matthew E. Wolkoff

Biology Theses

Lutzomyia shannoni (Dyar, 1929) (Diptera: Psychodidae) is the only known sand fly vector of vesicular stomatitis virus, a putative leishmaniasis vector, and also boasts the widest distribution of any sand fly in the New World. Research on Lu. shannoni in Central and South America has revealed genetically divergent subpopulations; however, tentative analysis of Lu. shannoni in the U.S. has failed to detect any significant population structure, even between specimens collected from highly disparate localities.

The present study used four molecular markers to more closely investigate the population structure of Lu. shannoni in the U.S., and assess the species ...


Mitigating Bioiversity Loss Of Native Plants, Jamie Ana Grigonis May 2018

Mitigating Bioiversity Loss Of Native Plants, Jamie Ana Grigonis

Student Theses 2015-Present

Growing up harvesting from my own vegetable garden and going from nursery to nursery with my mother, it has been extremely evident that plant biodiversity is more than just privet along driveways and carnations in window boxes. Plant biodiversity is often overlooked but crucial to having a healthy and thriving environment. Without certain plants, our ecosystems will crumble and this needs to be addressed now while it’s still at a level we can grow from. In my internship I am working alongside the director of the Thain Family Forest at the New York Botanical Gardens in order to get ...


Just Wrestle: How We Evolved Through Rough And Tumble Play, Rafe Kelley, Beth Kelley May 2018

Just Wrestle: How We Evolved Through Rough And Tumble Play, Rafe Kelley, Beth Kelley

Journal of Evolution and Health

No abstract provided.


Root Dynamics Of Crop Plants In A High Carbon Dioxide World: Effects Of Elevated Versus Ambient Carbon Dioxide Levels And No-Till Versus Conventional Agricultural Management, Charlotte Barker, Charlotte Jean Barker Mrs. May 2018

Root Dynamics Of Crop Plants In A High Carbon Dioxide World: Effects Of Elevated Versus Ambient Carbon Dioxide Levels And No-Till Versus Conventional Agricultural Management, Charlotte Barker, Charlotte Jean Barker Mrs.

Dissertations

Due to the continuing increases is atmospheric carbon dioxide levels and its potential effect on food sources, there is an interest in evaluating the effect of elevated CO2 concentration versus ambient CO2 concentration in agricultural crop plants although more studies have focused on the aboveground portions of plants rather than the roots. Additionally, the conservation agricultural method, no-till, has been widely suggested as a possible method of increasing soil organic carbon and increasing soil moisture in a hotter world.

This research involves two major agricultural plants, Sorghum bicolor (sorghum), and Glycine max (soybean) grown under four conditions including ...


Factors Affecting The Regrowth Of Ilex Glabra In A Routinely Burned Longleaf Forest, Jaybus Price May 2018

Factors Affecting The Regrowth Of Ilex Glabra In A Routinely Burned Longleaf Forest, Jaybus Price

Master's Theses

This study examines the effects of historical management by use of prescribed fire on Ilex glabra stems/m2 and factors affecting the regrowth of I. glabra after a prescribed burn to gain beneficial knowledge for management purposes. Environmental factors and morphological parameters of I. glabra were sampled before and after a prescribed burn of the Longleaf Trace Nature Preserve in September 2016. The study site is located in Lamar County, Mississippi, just west of Hattiesburg, MS. Stem densities of I. glabra were collected once before the prescribed burn and twice after the prescribed burn at 2 month and 9 ...


Habitat Associations And Detectability Of Three Unionid Species Along The Upper Sabine River In East Texas, Jared Dickson May 2018

Habitat Associations And Detectability Of Three Unionid Species Along The Upper Sabine River In East Texas, Jared Dickson

Biology Theses

East Texas contains the highest diversity of mussels in the state. Of the 37 species in East Texas, six are listed by the state as threatened and three have been proposed for listing as threatened or endangered under the U.S. Endangered Species Act. Although diverse, mussel populations are declining and few studies exist that establish habitat relationships identifying determinants of mussel distributions in the upper Sabine River. I explored potential habitat preferences of three state listed species using an occupancy modeling approach, including the: Texas Pigtoe, Fusconaia askewi, Sandbank Pocketbook, Lampsilis satura, and Texas Heelsplitter, Potamilus amphicaenus. Thirty sites ...


Impervious Surface And Macroinvertebrates In The South Atlanta Metropolitan Area, Christopher H. Kodani May 2018

Impervious Surface And Macroinvertebrates In The South Atlanta Metropolitan Area, Christopher H. Kodani

Georgia Journal of Science

Studies utilizing volunteer stream monitoring data are rare, particularly in in the Atlanta metropolitan area. This study investigated how the macroinvertebrate communities of 20 different stream sites in the south metropolitan Atlanta area were affected by the imperviousness of their surrounding watersheds. These sites were in a diverse landscape which included forests, wetlands, suburban day-use parks, and parking lots. Percentage impervious surface area was measured using Geographical Information System (GIS) analysis. Macroinvertebrates were collected using Georgia Adopt-A-Stream’s volunteer monitoring protocols, and a water quality index (WQI) was calculated from these data. The relationship between WQI and imperviousness was curvilinear ...


Sulfur Cave (Romania), An Extreme Environment With Microbial Mats In A Co2-H2S/O2 Gas Chemocline Dominated By Mycobacteria, Serban M. Sarbu, Joost W. Aerts, Jean-François Flot, Rob J.M. Van Spanning, Calin Baciu, Artur Ionescu, Boglárka M. Kis, Reka Incze, Sándor Sikó-Barabási, Zoltan Para, Botond Hegyeli, Nicu-Viorel Atudorei, Casey Barr, Kenneth Nealson, Ferenc L. Forray, Cristian Lascu, Emily J. Fleming, Wilbert Bitter, Radu Popa May 2018

Sulfur Cave (Romania), An Extreme Environment With Microbial Mats In A Co2-H2S/O2 Gas Chemocline Dominated By Mycobacteria, Serban M. Sarbu, Joost W. Aerts, Jean-François Flot, Rob J.M. Van Spanning, Calin Baciu, Artur Ionescu, Boglárka M. Kis, Reka Incze, Sándor Sikó-Barabási, Zoltan Para, Botond Hegyeli, Nicu-Viorel Atudorei, Casey Barr, Kenneth Nealson, Ferenc L. Forray, Cristian Lascu, Emily J. Fleming, Wilbert Bitter, Radu Popa

International Journal of Speleology

Sulfur Cave (Puturosu Mountain, Romania) is an extreme environment, unique for displaying life in a gas chemocline. The lower part of the cave is filled with CO2, CH4, and H2S of mofettic origin, while the upper part contains air that floats above the heavier volcanic gasses. S° and H2SO4 (from sulfur-oxidation) cover the cave wall at and below the CO2-H2S:O2 gas/gas interface. On the cave wall, near the interface the pH is < 1 and unusual microbial biofilms occur on the rock’s surface. We provide context information on the geology, mineralogy, chemistry and biology to better understand this unique environment. We have used X-ray diffraction, optical microscopy, scanning electron microscopy with EDAX capabilities, stable isotope analysis and 16S and 18S rDNA amplicon sequencing. The most common taxa in the microbial biofilms are Mycobacteria, Acidithiobacillus and Ferroplasmaceae. Liquid water in this system originates solely from condensation of water ...


Occupancy Modeling Of Parnassius Clodius Butterfly Populations In Grand Teton National Park, Wyoming, Kimberly E. Szcodronski, Diane M. Debinski, Robert W. Klaver May 2018

Occupancy Modeling Of Parnassius Clodius Butterfly Populations In Grand Teton National Park, Wyoming, Kimberly E. Szcodronski, Diane M. Debinski, Robert W. Klaver

Natural Resource Ecology and Management Publications

Estimating occupancy patterns and identifying vegetation characteristics that influence the presence of butterfly species are essential approaches needed for determining how habitat changes may affect butterfly populations in the future. The montane butterfly species, Parnassius clodius, was investigated to identify patterns of occupancy relating to habitat variables in Grand Teton National Park and Bridger-Teton National Forest, Wyoming, United States. A series of presence–absence surveys were conducted in 2013 in 41 mesic to xeric montane meadows that were considered suitable habitat for P. clodius during their flight season (June–July) to estimate occupancy (ψ) and detection probability (p). According to ...


Condition-Dependent Life History Strategies, Shivani V. Jadeja May 2018

Condition-Dependent Life History Strategies, Shivani V. Jadeja

Dissertations and Theses in Biological Sciences

Many organisms evolve condition-dependent life history strategies to maximize their lifetime fitness in response to intrinsic and extrinsic processes. I investigated a sequentially flowering plant’s strategy to allocate resources to retain flowers versus grow existing basal fruits to a larger size, using the plant Yucca glauca. The sink strength hypothesis suggests basal fruits are nutrient sinks depriving distal flowers of resources and reducing their probability of retention. A low probability of retention of distal flowers can also be explained by the architectural effects hypothesis. This hypothesis posits inherent positional differences in structures along an inflorescence such as flower size ...


The Influence Of Multiyear Drought-Driven Habitat Loss On The Bear Lake Sculpin (Cottus Extensus) And The Bear Lake Strain Of The Bonneville Cutthroat Trout (Oncorhynchus Clarkii Utah), Hayley C. Glassic May 2018

The Influence Of Multiyear Drought-Driven Habitat Loss On The Bear Lake Sculpin (Cottus Extensus) And The Bear Lake Strain Of The Bonneville Cutthroat Trout (Oncorhynchus Clarkii Utah), Hayley C. Glassic

All Graduate Theses and Dissertations

Multiyear drought is expected to increase in occurrence and severity in dry regions across the world, such as the American Southwest, endangering native species and ecosystem health. The effects of multiyear drought are often worsened by human water use for consumption, energy production, and agriculture, which, in lakes and reservoirs, cause reduced lake elevation. Reductions in lake elevation may leave previously submerged habitat stranded along shorelines and make tributaries inaccessible to fishes. Here, we show that decreasing lake elevation, associated with drought and water withdrawal, reduces the availability of shoreline cobble habitat to fishes and increases tributary distance by creating ...