Download or read book Lethal and Sublethal Effects of Nutrient Pollution on Amphibian Larvae written by Julia Elizabeth Earl and published by . This book was released on 2007 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents results of three experiments which were performed to further develop developmental stability for use in the conservation of amphibian species and to examine the toxicity of nutrients.
Download or read book The Effects of a Chemical Stressor on Amphibian Larvae written by Christine Marie Bridges and published by . This book was released on 1999 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are an increasing number of studies are now focusing on the effects that xenobiotics have on amphibians, an interest likely stimulated by widespread reports of amphibian declines. Chemical contamination may be partially to blame for these declines, by disrupting amphibian growth, reproduction, and behavior. However, evidence that xenobiotics, are directly to blame for these population declines is sparse, because environmental xenobiotic concentrations typically are not great enough to generate direct or immediate mortality. I, therefore, examined the effects of exposure of tadpoles to sublethal levels of contaminants because they may lead to the subtle changes that are ultimately contributing to population declines. Tadpoles acutely exposed to sublethal carbaryl concentrations decreased spontaneous swimming activity and swimming performance (i.e., sprint distance). When tadpoles were chronically exposed to sublethal carbaryl levels, there was an increase in mortality as well as the incidence of deformities. Furthermore, tadpoles exposed to carbaryl as eggs were smaller at metamorphosis than their corresponding controls. Consequently, it is possible that chemicals (e.g., carbaryl) in the environment are responsible for causing some amphibian declines by altering tadpole behavior, growth, and development, which ultimately may affect population dynamics. Using two assays (one lethal, one sublethal), I observed a significant degree of variation in tolerance to carbaryl at three of the hierarchical levels I examined: among nine ranid species, among ten populations of a single species, Rana sphenocephala, and within several populations of R, sphenocephala, and among full- and half-sibling families. Although it may be predicted that species in decline are more sensitive to environmental stressors (e.g., chemicals), two of the three species that are currently in decline were the most tolerant to carbaryl. Significant variation among R. sphenocephala populations and among families within these populations suggests that caution should be taken when making inferences to other populations or families, respectively. When examining differences among paternal half-sibling families, I found no significant variation in tolerance to carbaryl, indicating that little variation is available for adaptation to environmental stressors within this population. Determining the degree of variation in responses within and among amphibian species is important to amphibian conservation, because only when variation is present will amphibians have the ability to adapt and persist in changing environments.
Download or read book Effects of Pesticides on Amphibians with Special Reference to the Pyrethroid Insecticide Cypermethrin written by Lindsay M. Biga and published by . This book was released on 2013 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pollution by pesticides is a ubiquitous concern for wildlife. The effects of pesticides are especially concerning in aquatic environments, which are particularly vulnerable as they have several exposure routes for the influx of chemicals. These effects are of particular concern as biodiversity loss reaches unprecedented rates. This includes recent declines of amphibian populations and loss of amphibian species. Pesticide exposure may contribute to some amphibian populations and extinctions. This dissertation explores the effects of pesticides on amphibians, with particular reference to the pyrethroid insecticide cypermethrin. I first synthesized acute toxicity data of pesticides for amphibians from the literature (Chapter 2). Using 96h LC50 values for amphibian larvae exposed to insecticides, herbicides, and fungicides, I determined that amphibian species cannot be systematically classified as sensitive or tolerant to pesticides. Rather, relative acute lethal toxicities varied among species and between chemicals and types of pesticides even within a species, indicating that no amphibian species from this analysis can represent anticipated toxic effects to all amphibians. I next examined the differences in sensitivity to cypermethrin among three developmental stages for three anuran (frog) species (Chapter 3). I experimentally exposed embryos, recently hatched larvae and larvae with limb buds to cypermethrin in the laboratory. Exposure to cypermethrin had lethal and sublethal effects on some species and stages, but not all. The Pacific treefrog (Pseudacris regilla) was the most sensitive species and the early larval stage was the most sensitive for these three species. Additionally, cypermethrin exposure induced abnormal behavior in response to prodding for some species and stages. These results indicate differences in sensitivity to cypermethrin among species of amphibians. To further understand differences in sensitivity to pesticides among amphibians, I compared how three populations of P. regilla responded to cypermethrin exposure (Chapter 4). I performed a time-to-death assay in the laboratory, exposing newly hatched larvae from each population to cypermethrin under identical conditions. All populations had high rates of mortality when exposed to cypermethrin compared to unexposed controls and populations varied in the time to death. Moreover, exposed individuals were smaller than unexposed controls. Interestingly, population sensitivity did not appear to be associated with proximity to agriculture, but rather with elevation gradient, indicating that an evolved tolerance to pesticide exposure is not the mechanism for the differences in sensitivity observed here. To investigate the effects of cypermethrin on amphibians within a community context, I studied exposure in mesocosms (Chapter 5). I set up semi-natural aquatic ponds in enclosures that contained zooplankton, phytoplankton, and periphyton along with amphibian larvae. I experimentally exposed these mesocosms to cypermethrin and measured the effects on the amphibians and the other members of the community. Cypermethrin affected the entire aquatic community, even at the lowest dose, indicating the direct and indirect deleterious effects of cypermethrin on both invertebrate and vertebrate species in an aquatic community. This dissertation provides needed data on the effects of the pyrethroid insecticide cypermethrin on amphibians and their communities. Understanding the toxicity of newer, commonly used pesticides to non-target organisms is important as conservation biologists and managers make efforts to combat future amphibian population declines which may be associated with chemicals in the environment.
Download or read book Effects of Petroleum Distillates on Amphibian Development written by Kate Niermeier Ireton Walker and published by . This book was released on 2014 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: Petroleum distillates are widely used as an energy source and the extraction and disposal of these chemicals are done with little consideration of their effects on aquatic environments. Amphibians are considered excellent ecological indicators but little research has examined effects of petroleum distillates on aquatic species. I evaluated the lethal and sublethal effects on larval amphibians with exposure to petroleum distillates associated with various venues of pollution including hydraulic fracturing. I selected three petroleum distillates (kerosene, oil, and unleaded gasoline) that are known to have negative effects on aquatic organisms and are similar to the common constituents of mixtures used in hydraulic fracturing fluid. I examined effects of acute exposure to the water-soluble fraction of each of three distillates at four concentrations in four species: Anaxyrus americanus, Lithobates sphenocephalus, Hyla chrysoscelis, and Ambystoma maculatum. Specifically, I evaluated survival, level of narcosis, and swim time in response to a stimulus over a 72-hour period. I identified a significant distillate by time effect on response to stimulus and a distillate by concentration effect in all species except Hyla chrysoscelis. Anaxyrus americanus and Hyla chrysoscelis exhibited a significant three-way interaction among distillate, time, and concentration (p
Download or read book Ecotoxicology of Amphibians and Reptiles written by Donald W. Sparling and published by CRC Press. This book was released on 2010-06-02 with total page 946 pages. Available in PDF, EPUB and Kindle. Book excerpt: Building on the success of its popular predecessor, the second edition of Ecotoxicology of Amphibians and Reptiles presents newly available findings on the species that are important environmental indicators. This new edition covers nearly twice as many topics as the first, including recent developments in the ecotoxicology of amphibians and reptil
Download or read book Toxicology of Amphibian Tadpoles written by Eduardo Alves de Almeida and published by CRC Press. This book was released on 2023-12-15 with total page 558 pages. Available in PDF, EPUB and Kindle. Book excerpt: Anuran amphibians are among the animal groups with the highest rate of population decline on the planet. Among the factors driving this decline are environmental pollutants, whose negative effects on larvae and tadpoles are still relatively little studied. This is the first book devoted entirely to studying the effects of environmental pollutants on amphibian tadpoles. Throughout its 14 chapters, various aspects of the toxic effects of different classes of environmental contaminants are explored, such as the toxicokinetics of toxic compounds in tadpoles and their health effects, which may result in negative consequences at populations level.
Download or read book Environmental Health Perspectives written by and published by . This book was released on 1999 with total page 814 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Basic Environmental Toxicology written by Lorris G. Cockerham and published by Routledge. This book was released on 2019-07-05 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt: Basic Environmental Toxicology provides a thorough, systematic introduction to environmental toxicology and addresses many of the effects of pollutants on humans, animals, and the environment. Readers are introduced to the fundamentals of toxicology and ecotoxicology, the effects of different types of toxicants, and how toxicants affect different compartments of the environment. Fundamental aspects of environmental health, occupational health, detection of pollutants, and risk assessment are discussed. The book is excellent for anyone involved in risk assessment or risk management, toxicologists, state and local public health officials, environmental engineers, industrial managers, consultants, and students taking environmental toxicology courses.
Download or read book Development Strategies and Biodiversity written by David Costantini and published by Springer Nature. This book was released on 2022-02-15 with total page 319 pages. Available in PDF, EPUB and Kindle. Book excerpt: Development is a complex and highly dynamic process involving the cross talk among genes, maternal effects and environmental circumstances. Widespread evidence from plant to animal species show that variation in developmental conditions can modulate life history trajectories and influence key traits, such as growth, reproduction, and senescence. These effects are not limited to a single generation but can also be passed on future generations. This book aims to bring together studies of early life effects from the fields of evolutionary biology, global change biology, and biomedicine to synthesise and improve current knowledge of the mechanisms involved, and how variation in early life conditions translates into Darwinian fitness outcomes. Relying on examples of organisms’ responses to the ongoing and future environmental challenges of the Anthropocene, this book takes a novel approach to address the adaptive meaning of early life effects. The book has a broad scientific approach, targeting eco-evolutionary biologists, behavioural biologists, eco-physiologists, eco-toxicologists, as well as epidemiologists and biomedical scientists.
Download or read book Methods for Acute Toxicity Tests with Fish Macroinvertebrates and Amphibians written by Committee on Methods for Toxicity Tests with Aquatic Organisms and published by . This book was released on 1975 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Managing Soils and Terrestrial Systems written by Brian D. Fath and published by CRC Press. This book was released on 2020-07-29 with total page 665 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bringing together a wealth of knowledge, Environmental Management Handbook, Second Edition, gives a comprehensive overview of environmental problems, their sources, their assessment, and their solutions. Through in-depth entries and a topical table of contents, readers will quickly find answers to questions about environmental problems and their corresponding management issues. This six-volume set is a reimagining of the award-winning Encyclopedia of Environmental Management, published in 2013, and features insights from more than 400 contributors, all experts in their field. The experience, evidence, methods, and models used in studying environmental management are presented here in six stand-alone volumes, arranged along the major environmental systems. Features The first handbook that demonstrates the key processes and provisions for enhancing environmental management Addresses new and cutting-edge topics on ecosystem services, resilience, sustainability, food–energy–water nexus, socio-ecological systems, and more Provides an excellent basic knowledge on environmental systems, explains how these systems function, and offers strategies on how to best manage them Includes the most important problems and solutions facing environmental management today In this third volume, Managing Soils and Terrestrial Systems, the general concepts and processes of the geosphere with its related soil and terrestrial systems are introduced. It explains how these systems function and provides strategies on how to best manage them. It serves as an excellent resource for finding basic knowledge on the geosphere systems and includes important problems and solutions that environmental managers face today. This book practically demonstrates the key processes, methods, and models used in studying environmental management.
Download or read book AMPHIBIAN CONSERVATION written by Semlitsch R and published by Smithsonian. This book was released on 2003-06-17 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: Leading amphibian biologist Semlitsch has assembled experts to tackle the timely issue of disappearing and deformed populations of amphibians. Every environmentalist will find this book an accessible and informative examination of what many scientists have called one of the major threats to the world's biodiversity.
Download or read book Ecological Impacts of Toxic Chemicals written by Francisco Sánchez-Bayo, Paul J. van den Brink, Reinier M. Mann and published by Francisco Sanchez-Bayo. This book was released on 2011-09-09 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ecological Impacts of Toxic Chemicals presents a comprehensive, yet readable account of the known disturbances caused by all kinds of toxic chemicals on both aquatic and terrestrial ecosystems. Topics cover the sources of toxicants, their fate and distribution through the planet, their impacts on specific ecosystems, and their remediation by natural systems. Each chapter is written by well-known specialists in those areas, for the general public, students, and even scientists from outside this field. The book intends to raise awareness of the dangers of chemical pollution in a world dominated by industry and globalization of resources. Because the problems are widespread and far reaching, it is hoped that confronting the facts may prompt better management practices at industrial, agricultural and all levels of management, from local to governmental, so as to reduce the negative impacts of chemical contaminants on our planet.
Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1987 with total page 952 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Short term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms written by and published by . This book was released on 1994 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Conservation Biology in Sub Saharan Africa written by Richard Primack and published by Open Book Publishers. This book was released on 2019-09-10 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: Conservation Biology in Sub-Saharan Africa comprehensively explores the challenges and potential solutions to key conservation issues in Sub-Saharan Africa. Easy to read, this lucid and accessible textbook includes fifteen chapters that cover a full range of conservation topics, including threats to biodiversity, environmental laws, and protected areas management, as well as related topics such as sustainability, poverty, and human-wildlife conflict. This rich resource also includes a background discussion of what conservation biology is, a wide range of theoretical approaches to the subject, and concrete examples of conservation practice in specific African contexts. Strategies are outlined to protect biodiversity whilst promoting economic development in the region. Boxes covering specific themes written by scientists who live and work throughout the region are included in each chapter, together with recommended readings and suggested discussion topics. Each chapter also includes an extensive bibliography. Conservation Biology in Sub-Saharan Africa provides the most up-to-date study in the field. It is an essential resource, available on-line without charge, for undergraduate and graduate students, as well as a handy guide for professionals working to stop the rapid loss of biodiversity in Sub-Saharan Africa and elsewhere.
Download or read book Harmful Cyanobacteria written by Jef Huisman and published by Springer Science & Business Media. This book was released on 2005-06-15 with total page 249 pages. Available in PDF, EPUB and Kindle. Book excerpt: This outstanding volume provides an up-to-date overview of the advances in our knowledge of harmful cyanobacteria. An essential reference for all scientists and environmental professionals interested in cyanobacterial ecology and water management.
