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Wet Meadow Plant Associations, Malheur National Wildlife Refuge, Harney County, Oregon, John A. Christy Jan 2013

Wet Meadow Plant Associations, Malheur National Wildlife Refuge, Harney County, Oregon, John A. Christy

Institute for Natural Resources Publications

In July 2012, we sampled 131 plots in wet meadow habitat at the southern end of the Malheur National Wildlife Refuge. Analysis of the data identified eleven different plant associations: Alopecurus pratensis, Carex aquatilis var. aquatilis, Carex nebrascensis, Carex pellita, Carex praegracilis, Carex sheldonii, Distichlis spicata, Juncus balticus, Leymus triticoides, Phalaris arundinacea, and Sparganium eurycarpum. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores help to place the plant associations within gradients in soil moisture and alkalinity. The Alopecurus …


Resilience In Quaking Aspen: Recent Advances And Future Needs, Paul C. Rogers, C. Eisenberg, S. Clair Jan 2013

Resilience In Quaking Aspen: Recent Advances And Future Needs, Paul C. Rogers, C. Eisenberg, S. Clair

Wildland Resources Faculty Publications

Quaking Aspen (Populus tremuloides) sustainability is a topic of intense interest in forest ecology. Reports range from declines to persisting or increasing coverage in some areas. Moreover, there is little agreement on ultimate factors driving changes. Low aspen recruitment has been attributed to climate patterns, past management, herbivore increases, competitive interactions with conifers, predator and beaver extirpation, and livestock grazing. Several of these potential causes result from direct or indirect actions of human agency. On June 27–28, 2012 a group of leading aspen ecologists from diverse backgrounds convened at the High Lonesome Ranch in western Colorado to address the state …


Experiments To Measure The Effects Of Timber Harvesting Equipment On Surface Lithic Scatters, Douglas J. Baughman Jan 2013

Experiments To Measure The Effects Of Timber Harvesting Equipment On Surface Lithic Scatters, Douglas J. Baughman

All Master's Theses

The importance of cultural resource preservation cannot be overstated; however local economies are at least as important. Due to conservative archaeological site protection practices in Region 5 of the United States Forest Service, the economy of Northeastern California is being adversely affected. In an attempt to help the Forest Service make more informed management decisions and improve the Northeastern California economy, I undertook experiments on the effects of timber harvesting on lithic scatters on Modoc National Forest. The experiments involved placement of 225 glass tiles (proxy lithics) in each of three plots subject to vehicle traffic and log dragging by …


Evaluating The Utility Of Beaver Reintroduction Programs For Enhancing Habitat For Rainbow Trout And Steelhead, Jonathan Rodger Hegna Jan 2013

Evaluating The Utility Of Beaver Reintroduction Programs For Enhancing Habitat For Rainbow Trout And Steelhead, Jonathan Rodger Hegna

All Master's Theses

Beaver reintroduction programs are increasingly being viewed as a way to enhance salmonid habitat and production. However, the actual effectiveness of using beavers as a habitat enhancement tool for ESA listed steelhead Oncorhynchus mykiss populations is unknown. We examined the type of habitat, at both the microhabitat and mesohabitat levels, preferred by steelhead in three small streams in the upper Yakima Basin, WA through standard snorkel surveys and habitat measurements. Our results suggest that steelhead in small streams strongly prefer (relative to availability) microhabitats that have deeper water(> 30 cm), slow stream velocities(< 0 .05 mis), and complex cover types. Habitat partitioning among the size-classes (small< 50 mm, medium 50-90 mm, large> 90 mm total length, TL) principally operated …


State Of The River Report For The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, And Contaminants 2013, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University Jan 2013

State Of The River Report For The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, And Contaminants 2013, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University

State of the River Report

No abstract provided.


University Of North Florida Climate Action Plan, University Of North Florida Environmental Center Jan 2013

University Of North Florida Climate Action Plan, University Of North Florida Environmental Center

Campus Sustainability

The UNF Climate Action Plan, which was developed by the UNF Sustainability Committee, outlines how UNF will reduce its greenhouse gas emissions and become carbon neutral by the year 2050. The plan defines UNF institutional capacities and current initiatives for which ongoing support is necessary for success. Additionally, the CAP outlines actions essential for building UNF's capacity to effectively prepare for, implement and track mitigation projects. The plans include improving data collection systems, cultivation of student, faculty and staff support, and securing financial resources. These efforts will be completed in three phases and includes infrastructural improvements, operational changes and a …


West Chester University Climate Action Plan: Carbon Neutral By 2025, Tim Lutz, Executive Director Of Facilities Management, Climate Action Planning Team Jan 2013

West Chester University Climate Action Plan: Carbon Neutral By 2025, Tim Lutz, Executive Director Of Facilities Management, Climate Action Planning Team

WCU Campus Sustainability Initiatives

WEST CHESTER UNIVERSITY PRESIDENT GREG WEISENSTEIN signed the American College and University Presidents’ Climate Commitment (ACUPCC) in October 2010, pledging the University to a series of actions that will ultimately reduce net greenhouse gas emissions to zero. In doing so we joined more than 600 institutions in expressing our deep concern about global warming. More importantly, we accepted the challenge to provide leadership in our own community by “modeling ways to minimize global warming emissions, and by providing the knowledge and the educated graduates to achieve climate neutrality.” Since 2010 we have completed an inventory of greenhouse gas emissions (GHG), …


Net Effects Of Batrachochytrium Dendrobatidis (Bd) And Fungicides On Anurans Across Life Stages, Jenise Brown Jan 2013

Net Effects Of Batrachochytrium Dendrobatidis (Bd) And Fungicides On Anurans Across Life Stages, Jenise Brown

USF Tampa Graduate Theses and Dissertations

Amphibians are declining at alarming rates globally. Multiple factors contribute to these declines, including chemical contaminants and emergent diseases. In recent years, agrochemical use, especially fungicide applications, has increased considerably. Previous studies have demonstrated that these agrochemicals leave application sites and enter wetlands via runoff and have detrimental effects on non-target organisms. For example, exposure to contaminants can have multifarious effects on amphibians, such as reducing their ability to deal with a secondary stressor, such as disease.

A pathogen that is found concomitant with chemical contaminants in aquatic systems is Batrachochytrium dendrobatidis (Bd). Bd has decimated amphibian populations worldwide. Susceptibility …


The Water Culture Beliefs Of Embera Communities And Maternal And Child Health In The Republic Of Panama, Ilenia Anneth Forero Jan 2013

The Water Culture Beliefs Of Embera Communities And Maternal And Child Health In The Republic Of Panama, Ilenia Anneth Forero

USF Tampa Graduate Theses and Dissertations

Water has cultural and spiritual values to indigenous people. These beliefs expose them to unsafe water sources and make them vulnerable to waterborne diseases. This background is not taken into account when countries write their water legislations, therefor imposing a management of water not readily accepted by them. The Embera group is one of the indigenous groups from the Republic of Panama, who have strong water beliefs. They live along the shore of rivers in houses built on high stilts away from urban areas. The purpose of this cross-sectional community based study is to describe through a survey the relation …


Investigation Of Colored Dissolved Organic Matter (Cdom) Optical Properties, Nutrients, And Salinity In Coastal Florida: Springshed To Estuaries, Ana Rosa Arellano Jan 2013

Investigation Of Colored Dissolved Organic Matter (Cdom) Optical Properties, Nutrients, And Salinity In Coastal Florida: Springshed To Estuaries, Ana Rosa Arellano

USF Tampa Graduate Theses and Dissertations

Optical parameters measured via absorption spectroscopy and high-resolution fluorescence spectroscopy were used to characterize dissolved organic matter (DOM) in the springshed of Kings Bay, a spring-fed estuary located on Florida's Springs Coast. Over the past 40 years, springs supplying groundwater to Kings Bay have shown an increase in nitrate concentration. The overall goal of this project was to fingerprint wells and spring sites with elevated nitrogen concentrations using CDOM optical properties and establish relationships between nutrient and optical parameters. Samples were obtained from various sites: springs, Kings Bay surface (KBS), wells, coastal waters in and at the mouth of Crystal …


Fate Of Polybrominated Diphenyl Ethers During Wastewater Treatment Process Producing Reclaimed Water, Kristy Siegel Jan 2013

Fate Of Polybrominated Diphenyl Ethers During Wastewater Treatment Process Producing Reclaimed Water, Kristy Siegel

USF Tampa Graduate Theses and Dissertations

Polybrominated diphenyl ethers (PBDEs), flame retardants, have been applied to consumer goods, such as furniture, electrical devices, textiles, and appliances for decades. Due to their physico-chemical properties, PBDEs are semi-volatile and easily leach off the consumer good during aging, stress, or normal wear and tear of the good. Once airborne, they pose an environmental health threat because they can adsorb onto dust particles, soil, or other particulates that can be inhaled, ingested, or come into contact with the dermal layer. Additionally, PBDEs have a molecular structure similar to other persistent organic pollutants, such as polychlorinated biphenyls and polychlorinated dibenzo-p-dioxins and …


Improving Implementation Of A Regional In-Line Chlorinator In Rural Panama Through Development Of A Regionally Appropriate Field Guide, Benjamin A. Yoakum Jan 2013

Improving Implementation Of A Regional In-Line Chlorinator In Rural Panama Through Development Of A Regionally Appropriate Field Guide, Benjamin A. Yoakum

USF Tampa Graduate Theses and Dissertations

Access to safe drinking water has a direct effect on improving human health and their quality of life. One country still struggling with providing access to safe drinking water to all of its population is Panama. Panama's largest indigenous group, the Ngöbe people, is disproportionately affected by lack of access to safe drinking water. One way Panama's Ministry of Health (MINSA) is attempting to increase access to safe drinking water to the Ngöbe people is by disinfecting the water already captured by rural gravity fed water systems constructed within in the Ngöbe-Bugle reservation. This is accomplished using an in-line chlorinator …


Pine Creek Conservation Area: 2013 Mapping And Monitoring Report, Eric M. Nielsen, Matthew D. Noone, James S. Kagan, Matthew T. Lee Jan 2013

Pine Creek Conservation Area: 2013 Mapping And Monitoring Report, Eric M. Nielsen, Matthew D. Noone, James S. Kagan, Matthew T. Lee

Institute for Natural Resources Publications

Pine Creek Conservation Area (PCCA), just northeast of the John Day River in Wheeler County, Oregon, was acquired in 1999-2001 by the Confederate Tribes of Warm Springs with support from the Bonneville Power Administration (BPA), to mitigate for wildlife losses created by the large, hydropower Columbia River Dams, particularly the Bonneville, Dalles and John Day Dams. Many thousands of acres of grassland, shrub steppe and riparian habitats were lost due to inundation, and the objectives of the acquisition included restoration of similar habitats. As part of an interagency agreement created in 2002, the Oregon Natural Heritage Information Center established a …


Monitoring The Survival Of Hatchery-Produced Spat And Larvae On Louisiana Public Oyster Reefs, Erin R. Leonhardt Jan 2013

Monitoring The Survival Of Hatchery-Produced Spat And Larvae On Louisiana Public Oyster Reefs, Erin R. Leonhardt

LSU Master's Theses

Alternative or supplemental management activities may be necessary to restore and enhance oyster production on Louisiana public oyster reefs. The production of wild oysters is variable due to anthropogenic and environmental factors that affect recruitment, growth and survival. The availability and structure of cultch material for larval recruitment and survival is particularly important to maintain oyster production. Beginning in 2011, the Sea Grant Oyster Hatchery on Grand Isle, LA and the Louisiana Department of Wildlife and Fisheries (LDWF) collaborated to test the survival of hatchery-produced spat and hatchery-produced larvae deployed on public oyster grounds and cultch plant sites. In 2011, …


Spatial And Temporal Patterns Of Amphibian Chytrid Fungus Batrachochytrium Dendrobatidis Occupancy In Amphibian Habitats, Tara Chestnut Jan 2013

Spatial And Temporal Patterns Of Amphibian Chytrid Fungus Batrachochytrium Dendrobatidis Occupancy In Amphibian Habitats, Tara Chestnut

Environmental Science and Management Professional Master's Project Reports

Chytrid fungi are the most ancestral of the fungi and are global in distribution. There are over 1200 species of Chytridiomycota described from freshwater, marine and terrestrial systems in temperate, tropical and tundra environments. Chytridiales are characterized by a range of morphologies and share the flask- or pot-like shape of the zoosporangia, within which motile zoospores develop. Chytrids function primarily as plant saprobes and parasites, but some also parasitize animals. Chytrids are observed in conjunction with the decline of freshwater and marine algal blooms, they decompose excess pollen, and comprise the fungal flora in gut of herbivores. Some chytrids also …


Population Ecology Of The Ribbed Mussel In Southeastern Louisiana, Aaron Jacob Honig Jan 2013

Population Ecology Of The Ribbed Mussel In Southeastern Louisiana, Aaron Jacob Honig

LSU Master's Theses

Benthic intertidal bivalves play an essential role in estuarine ecosystems by contributing to habitat provision, water filtration, and promoting productivity. As such, ecosystem level changes that impact population distributions and persistence of local bivalve populations may have large ecosystem level consequences, making it important to better understand the population distribution and ecology of native bivalve populations. Gametogenesis, recruitment, growth, mortality, size structure and density of the ribbed mussel, Geukensia demissa, were examined across a salinity gradient in southeastern Louisiana. In summer 2012, 100-m transects were placed at interior and edge marsh plots to collect data on mussel density, and vegetation …


Effect Of Solids Retention Time On The Denitrification Potential Of Anaerobically Digested Swine Waste, Maureen Njoki Kinyua Jan 2013

Effect Of Solids Retention Time On The Denitrification Potential Of Anaerobically Digested Swine Waste, Maureen Njoki Kinyua

USF Tampa Graduate Theses and Dissertations

Three continuously stirred tank reactors (CSTR) were operated in semi continuous mode treating swine waste using anaerobic digestion. The reactors were used to test the effect of solid retention time (SRT) on CH4 yield, total ammonia nitrogen (TAN) concentrations, % volatile solids (VS), chemical oxygen demand (COD) and volatile fatty acids (VFA) removal, readily biodegradable COD concentration and the denitrification potential for the effluent in a biological nutrient removal (BNR) system. During Phase I of the study, the three reactors were operated at the same 28 day SRT for 16 weeks. SRTs were then changed during the 12 week Phase …


Sawmill Slough Preserve At The University Of North Florida, James Taylor Jan 2013

Sawmill Slough Preserve At The University Of North Florida, James Taylor

Professional Presentations

Taylor, J.W., J. Lemmons and C. Hubbuch. 2013. Sawmill Slough Preserve, University of North Florida. Association for the Advancement of Sustainability in Higher Education (AASHE) Annual Conference. Nashville, TN. (Powerpoint)


Spatial And Temporal Patterns In Ungulate-Ecosystem Interactions, Bryan D. Murray Jan 2013

Spatial And Temporal Patterns In Ungulate-Ecosystem Interactions, Bryan D. Murray

Dissertations, Master's Theses and Master's Reports - Open

Ungulates are important components of a variety of ecosystems worldwide. This dissertation integrates aspects of ungulate and forest ecology to increase our understanding of how they work together in ways that are of interest to natural resource managers, educators, and those who are simply curious about nature. Although animal ecology and ecosystem ecology are often studied separately, one of the general goals of this dissertation is to examine how they interact across spatial and temporal scales. Forest ecosystems are heterogeneous across a range of scales. Spatial and temporal habitat use patterns of forest ungulates tend to be congregated in patches …


Qualitative And Quantitative Analysis Of Lignocellulosic Biomass Using Infrared Techniques: A Mini-Review, Feng Xu, Jianming Yu, Tesfaye Tesso, Floyd Dowell, Donghai Wang Jan 2013

Qualitative And Quantitative Analysis Of Lignocellulosic Biomass Using Infrared Techniques: A Mini-Review, Feng Xu, Jianming Yu, Tesfaye Tesso, Floyd Dowell, Donghai Wang

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Current wet chemical methods for biomass composition analysis using two-step sulfuric acid hydrolysis are time-consuming, labor-intensive, and unable to provide structural information about biomass. Infrared techniques provide fast, low-cost analysis, are non-destructive, and have shown promising results. Chemometric analysis has allowed researchers to perform qualitative and quantitative study of biomass with both near-infrared and mid-infrared spectroscopy. This review summarizes the progress and applications of infrared techniques in biomass study, and compares the infrared and the wet chemical methods for composition analysis. In addition to reviewing recent studies of biomass structure and composition, we also discuss the progress and prospects for …


Natural Treatment Systems As Sustainable Ecotechnologies For The Developing Countries, Qaisar Mahmood, Arshid Pervez, Bibi Saima Zeb, Habiba Zaffar, Hajra Yaqoob, Muhammad Waseem, Zahidullah, Sumera Afsheen Jan 2013

Natural Treatment Systems As Sustainable Ecotechnologies For The Developing Countries, Qaisar Mahmood, Arshid Pervez, Bibi Saima Zeb, Habiba Zaffar, Hajra Yaqoob, Muhammad Waseem, Zahidullah, Sumera Afsheen

Plant and Soil Sciences Faculty Publications

The purpose of natural treatment systems is the re-establishment of disturbed ecosystems and their sustainability for benefits to human and nature. The working of natural treatment systems on ecological principles and their sustainability in terms of low cost, low energy consumption, and low mechanical technology is highly desirable. The current review presents pros and cons of the natural treatment systems, their performance, and recent developments to use them in the treatment of various types of wastewaters. Fast population growth and economic pressure in some developing countries compel the implementation of principles of natural treatment to protect natural environment. The employment …


Trace Metals In Sediments On The Continental Margin Of The Northwest Atlantic Ocean, Daniel L. Marsh Jan 2013

Trace Metals In Sediments On The Continental Margin Of The Northwest Atlantic Ocean, Daniel L. Marsh

Browse all Theses and Dissertations

Trace metals in the ocean are derived from natural and anthropogenic sources. Despite increased human impact on the marine environment and biological productivity of continental margins, trace metal studies in marine sediments have focused primarily on near-shore regions. I investigated 22 metals in sediments on the continental margin of the northwest Atlantic Ocean to calculate enrichment factors (EF) relative to upper continental crust and identify spatial variations with distance from shore and depth below the sediment-seawater interface. Metals were well correlated with Al, Fe, organic matter, or CaCO3. No clear trends in metal EFs with distance from shore were evident …


Quantitative Analysis Of The Polarity Reversal Pattern Of The Earth's Magnetic Field And Self-Reversing Dynamo Models, Patrick Shane Craig Jan 2013

Quantitative Analysis Of The Polarity Reversal Pattern Of The Earth's Magnetic Field And Self-Reversing Dynamo Models, Patrick Shane Craig

Browse all Theses and Dissertations

The geologic record documents that the Earth's magnetic field has reversed 284 times over the past 160 Myr. This study uses two methods to analyze the scaling properties of the pattern of geomagnetic reversals and to analyze the scaling properties of reversals output by two mathematical self-reversing dynamo models, the Rikitake (1958) two-disk dynamo and the magnetohydrodynamic (MHD) model of Driscoll and Olson (2011). The first analysis method plots the duration versus cumulative probability for geomagnetic polarity intervals ranging between 0.01 and 35 Myr. The Kolmogorov-Smirnov statistic is used to determine the optimal minimum value of xmin at which power …


Palaeoecological Analysis Of The Decline In Stromatolite Abundance During The Ordovician Period, Noran Mhm El-Sherif Jan 2013

Palaeoecological Analysis Of The Decline In Stromatolite Abundance During The Ordovician Period, Noran Mhm El-Sherif

Browse all Theses and Dissertations

A stromatolite is a laminated benthic microbial deposit. Its uniqueness arises from being present since the Precambrian to the present. Stromatolites recorded a peak time during the Mesoproterozoic, subsequently they witnessed abrupt rises and falls in abundance with the steepest decline in the Ordovician period, from which it never recovered from. There is no consensus yet regarding the reasons behind the decline of stromatolites. Thus the decline of these microbial deposits remains an enigma. Additionally, a literature gap exists regarding the reasons that specifically led to the Ordovician decline. Accordingly, the focus of this literature-based MSc. thesis is to find …


Abiotic Degradation Of Chlorinated Hydrocarbons (Chcs) With Zero-Valent Magnesium (Zvm) And Zero-Valent Palladium/Magnesium Bimetallic (Pd/Mg)-Reductant, Fang Yu Jan 2013

Abiotic Degradation Of Chlorinated Hydrocarbons (Chcs) With Zero-Valent Magnesium (Zvm) And Zero-Valent Palladium/Magnesium Bimetallic (Pd/Mg)-Reductant, Fang Yu

Browse all Theses and Dissertations

Chlorinated hydrocarbons (CHCs) in groundwater can be treated by monometallic and bimetallic metal reductants through abiotic degradation. The breakdown of CHC is achieved by gaining electrons from those reductants and removing chlorines from CHC molecules to transform the CHCs into less chlorinated compounds. As a proven technology in groundwater treatment, permeable reactive barriers (PRBs) have been used to passively treat contaminated groundwater, in which granular metals can be used as reactive materials. This study explored the abiotic degradation of CHCs by zero-valent magnesium (ZVM) and bimetallic palladium/magnesium (Pd/Mg) reductants. Different CHCs (carbon tetrachloride, chloroform, dichloromethane (DCM), 1,2-dichloroethane (1,2-DCA), 1,1,2-trichloroethane (1,1,2-TCA), …


Factors Influencing The Establishment And Survival Of Native Hardwood Tree Seedlings Of The Kentucky Inner Bluegrass Blue Ash-Oak Savanna-Woodland, James D. Shaffer Jan 2013

Factors Influencing The Establishment And Survival Of Native Hardwood Tree Seedlings Of The Kentucky Inner Bluegrass Blue Ash-Oak Savanna-Woodland, James D. Shaffer

Theses and Dissertations--Biology

Historically, the Kentucky Inner Bluegrass blue ash-oak savanna-woodland was the primary ecosystem of the Inner Bluegrass Region (IBR) of Kentucky. After European settlement, the majority (>99%) of Bluegrass savanna was converted to agricultural and urban land uses. Currently remnant savanna tree species are failing to recruit. Therefore, a long-term restoration ecology project researching competition and disturbance on seedling establishment, survival, and growth has been established at Griffith Woods (the largest remaining savanna in Kentucky) in Harrison Co., KY. Fourteen native hardwood tree species (a total of 6,168 seedlings) have been experimentally planted. Light, soil, surrounding vegetation, and herbivory, factors …


The Floodplain Food Web Mosaic: A Study Of Its Importance To Salmon And Steelhead With Implications For Their Recovery, J. Ryan Bellmore, Colden V. Baxter, Kyle Martens, Patrick J. Connolly Jan 2013

The Floodplain Food Web Mosaic: A Study Of Its Importance To Salmon And Steelhead With Implications For Their Recovery, J. Ryan Bellmore, Colden V. Baxter, Kyle Martens, Patrick J. Connolly

United States Geological Survey: Staff Publications

Although numerous studies have attempted to place species of interest within the context of food webs, such efforts have generally occurred at small scales or disregard potentially important spatial heterogeneity. If food web approaches are to be employed to manage species, studies are needed that evaluate the multiple habitats and associated webs of interactions in which these species participate. Here, we quantify the food webs that sustain rearing salmon and steelhead within a floodplain landscape of the Methow River, Washington, USA, a location where restoration has been proposed to restore side channels in an attempt to recover anadromous fishes. We …


The Malthusian–Darwinian Dynamic And The Trajectory Of Civilization, Jeffrey C. Nekola, Craig D. Allen, James H. Brown, Joseph R. Burger, Ana D. Davidson, Trevor S. Fristoe, Marcus J. Hamilton, Sean T. Hammond, Astrid Kodric-Brown, Norman Mercado-Silva, Jordan G. Okie Jan 2013

The Malthusian–Darwinian Dynamic And The Trajectory Of Civilization, Jeffrey C. Nekola, Craig D. Allen, James H. Brown, Joseph R. Burger, Ana D. Davidson, Trevor S. Fristoe, Marcus J. Hamilton, Sean T. Hammond, Astrid Kodric-Brown, Norman Mercado-Silva, Jordan G. Okie

United States Geological Survey: Staff Publications

Two interacting forces influence all populations: the Malthusian dynamic of exponential growth until resource limits are reached, and the Darwinian dynamic of innovation and adaptation to circumvent these limits through biological and/or cultural evolution. The specific manifestations of these forces in modern human society provide an important context for determining how humans can establish a sustainable relationship with the finite Earth.


A Causal Examination Of The Effects Of Confounding Factors On Multimetric Indices, Donald R. Schoolmaster Jr., James B. Grace, E. William Schweiger, Brian R. Mitchell, Glenn R. Guntenspergen Jan 2013

A Causal Examination Of The Effects Of Confounding Factors On Multimetric Indices, Donald R. Schoolmaster Jr., James B. Grace, E. William Schweiger, Brian R. Mitchell, Glenn R. Guntenspergen

United States Geological Survey: Staff Publications

The development of multimetric indices (MMIs) as a means of providing integrative measures of ecosystem condition is becoming widespread. An increasingly recognized problem for the interpretability of MMIs is controlling for the potentially confounding influences of environmental covariates. Most common approaches to handling covariates are based on simple notions of statistical control, leaving the causal implications of covariates and their adjustment unstated. In this paper, we use graphical models to examine some of the potential impacts of environmental covariates on the observed signals between human disturbance and potential response metrics. Using simulations based on various causal networks, we show how …


Comparative Embryotoxicity Of A Pentabrominated Diphenyl Ether Mixture To Common Terns (Sterna Hirundo) And American Kestrels (Falco Sparverius), Barnett A. Rattner, Rebecca S. Lazarus, Gary H. Heinz, Natalie K. Karouna-Renier, Sandra L. Schultz, Robert C. Hale Jan 2013

Comparative Embryotoxicity Of A Pentabrominated Diphenyl Ether Mixture To Common Terns (Sterna Hirundo) And American Kestrels (Falco Sparverius), Barnett A. Rattner, Rebecca S. Lazarus, Gary H. Heinz, Natalie K. Karouna-Renier, Sandra L. Schultz, Robert C. Hale

United States Geological Survey: Staff Publications

Concentrations of polybrominated diphenyl ethers (PBDEs) in Forster’s tern (Sterna forsteri) eggs from San Francisco Bay have been reported to range up to 63 µg g-1 lipid weight. This value exceeds the lowest-observed-adverse-effect level (1.8 µg g-1 egg wet weight; ~32 µg g-1 lipid weight) reported in an embryotoxicity study with American kestrels (Falco sparverius). As a surrogate for Forster’s terns, common tern (Sterna hirundo) eggs were treated by air cell injection with corn oil vehicle (control) or a commercial penta-BDE formulation (DE-71) at nominal concentrations of 0.2, 2, and 20 µg g …