The stable chromium (Cr) isotope system has emerged over the past decade as a new tool to track changes in the amount of oxygen in earth's ocean-atmosphere system. Much of the initial foundation for using Cr isotopes ( 53Cr) as a paleoredox proxy has required recent revision. However, the basic idea behind using Cr isotopes as redox tracers is straightforward-the largest isotope fractionations are redox-dependent and occur during partial reduction of Cr(VI). As such, Cr isotopic signatures can provide novel insights into Cr redox cycling in both marine and terrestrial settings. Critically, the Cr isotope system-unlike many other trace metal proxies-can respond to short-term redox perturbations (e.g., on timescales characteristic of Pleistocene glacial-interglacial cycles). The Cr isotope system can also be used to probe the earth's long-term atmospheric oxygenation, pointing towards low but likely dynamic oxygen levels for the majority of Earth's history.

Nitrogen is an essential nutrient for life, and its sources and cycling have varied over earth history. Stable isotope ratios of nitrogen compounds (expressed as 15N, in 0/00) are preserved in the sedimentary record and track these changes, providing important insights into associated biogeochemical feedbacks. Here we review the use of nitrogen stable isotope geochemistry in unravelling the evolution of the global N cycle in deep time. We highlight difficulties with preservation, unambiguous interpretations, and local versus global effects. We end with several case studies illustrating how depositional and stratigraphic context is crucial in reliably interpreting 15N records in ancient marine sediments, both in ancient anoxic (Archean) and more recent well oxygenated (Phanerozoic) environments.

This book provides insights and a capacity to understand the climate change phenomenon, its impact on water resources, and possible remedial measures. The impact of climate change on water resources is a global issue and cause for concern. Water resources in many countries are extremely stressed, and climate change along with burgeoning populations, the rise in living standards, and increasing demand on resources are factors which serve to exacerbate this stress. The chapters provide information on tools that will be useful to mitigate the adverse consequences of natural disasters. Fundamental to addressing these issues is hydrological modelling which is discussed in this book and ways to combat climate change as an important aspect of water resource management.

This book combines multidisciplinary studies on the environmental consequences of intensified use of land and water, and the fusion of land to provide food for a growing population. Studies on water, vegetation, and soil are addressed from an environmental management perspective with a special focus on the relation between natural elements and humans. This book considers the essential dynamics of humans and the natural environment, which is especially important in areas with shallow water-table that influence directly on agricultural activities (crops, livestock, and forests), land management, flooding, droughts, waterlogging, salt-affected soils (saline and sodic) and variation in obtained water quality in wells where these processes as related to the local and regional geomorphology control. The studies present hydrological processes towards the definition of an adequate use of soil and water with consequences of its management on the environment. Also, water study procedures are presented as well as their relation to other elements of the landscape. Methodologies such as the Tothian flow system concept are recognized by different authors to provide the reader with solid interdisciplinary analyses of related environmental components such as soils, vegetation, surface water, geomorphology, geological framework and groundwater physical-chemical composition.

Vanadium isotope ratios (51V/50V) have potential to provide information about changes in past ocean oxygen contents. In particular, V isotopes may find utility in tracing variations at non-zero oxygen concentrations because the redox couple that controls V elemental and isotopic abundances in seawater (vanadate-vanadyl) appears to operate around 10M O2. This characteristic sets V isotopes apart from many other metal isotope redox proxies that require more reducing conditions to register significant changes in their isotope budgets. The oxygen abundance sensitivity range of V isotopes suggests that this paleoproxy could be particularly useful in tracing marine oxygenation changes throughout the Phanerozoic and potentially beyond.

Reconstruction of ocean paleoproductivity and paleochemistry is paramount to understanding global biogeochemical cycles such as the carbon, oxygen and sulfur cycles and the responses of these cycles to changes in climate and tectonics. Paleo-reconstruction involves the application of various tracers that record seawater compositions, which in turn may be used to infer oceanic processes. Several important tracers are incorporated into pelagic barite, an authigenic mineral that forms in the water column. Here we summarize the utility of pelagic barite for the reconstruction of export production and as a recorder of seawater S, O, Sr, Ca and Ba.

This book is a multidisciplinary manuscript bringing together contributions on water issues from natural and social scientists focused on water management and structures in a challenging environmental situation such as Dakhla Oasis in Egypt's western desert. The authors of this book are relevant scientists in hydrology, geology, remote sensing, agriculture, history, and sociology. It is devoted to various critical environmental topics such as geological and hydraulic structure, climate influence, underground water management, irrigation management, and human settlement. The book provides a range of new perspectives on solving different environmental problems in arid zones toward the region's sustainable development, based on the case studies and fieldwork in the Dakhla Oasis (Western Desert, Egypt).

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 fourth volume, Managing Water Resources and Hydrological Systems, the reader is introduced to the general concepts and processes of the hydrosphere with its water resources and hydrological systems. This volume serves as an excellent resource for finding basic knowledge on the hydrosphere 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.

Among the deep-sea marine invertebrates, pycnogonids and crustaceans represent ecologically important and most diverse groups of species. Yet both are still poorly understood. Sampling and exploring operations off the west and east coast of the Americas has significantly increased in the last two decades. However such operations are very costly and limited in number and frequency. In countries like Brazil, Canada, Chile, Colombia, Costa Rica, Mexico, Peru, the United States of America, and El Salvador a large effort has been made to explore the deep-sea resources and the rich diversity of the communities, resulting in a better understanding of the natural ecosystems on both coasts of America. Pycnogonids and many groups of deep-sea crustaceans have been intensively studied, from the smallest animals, like the mostly unknown benthic copepods to the largest decapods. This book presents new and updated information on various groups of deep-sea pycnogonids and crustaceans occurring off the American continent. Offering a valuable reference resource for scientists interested in this fascinating fauna, it includes review papers and new data on the deep-sea communities occurring off the USA, Mexico, El Salvador, Costa Rica, Colombia, Chile, Peru, Brazil and Argentina, as well as in larger areas in both the East Pacific and the West Atlantic. As such it covers most of the current deep-water research in Latin America.

This book presents the phylogeny, taxonomy and biogeography of freshwater red algae. Its content is divided into five chapters. The first chapter provides a brief history of freshwater red algal research, habits and collecting methods, general biogeographic trends and an overview of the taxonomic/phylogenetic placement of freshwater taxa. The other four chapters are taxonomic treatments of non-marine red algae based on taxonomic levels, i.e. classes within the phylum Rhodophyta, orders within each class, families within each order, and genera within each family. Descriptions, phylogenetic data (including numerous trees), geographic range (maps for most species) and dichotomous keys for identification are presented. Comprehensive data are provided for more than 220 species.

This book provides an innovative, realistic and reliable solution to the common problem of Indian water and energy sector due to the onset of the Impact of Climate Change and Large-Scale Urbanization. Twelve Case Studies and One Review Paper that were included in this book depict the way soft computation techniques, simulation and decision-making framework can optimize the best solution from multiple solutions to the problems of water and energy management which corresponds to a novel symbiotic and synchronous nexus between water and the energy sector. All the studies included in this book are collected from all parts of India. The selected studies utilized the latest technologies like Multi-Criteria Decision Frame Work, Neural Networks and Nature-Based Optimization techniques to achieve diverse objectives from the prediction of climatic parameters to yield from ungauged watershed to performance optimization of Water Treatment Plant, Hydropower as well as futuristic alternative energy systems like Wave to Power Plants.