Natural emissions of methane have received much attention over the last decade due to the documented increase of methane in the atmosphere and high global warming potential relative to CO2. Over the past few decades the Arctic has been warming approximately four times faster than the rest of the planet, driving a pressing need to assess the current and future vulnerability of various natural methane sources. In the Arctic, vast amounts of methane is stored in soils and permafrost or is being generated as permafrost thaw continues. Additionally, there are large stores of methane in Arctic gas hydrates, a solid form of concentrated methane and water, and in numerous settings, including deep-water marine areas, on continental shelves hosting relict subsea permafrost and gas hydrate, in and beneath onshore permafrost, and likely beneath the Greenland Ice Sheet. Continued climate warming is making methane leakage more likely. Even deeper conventional gas reservoirs could leak methane as the overlying permafrost degrades.

Overviews of the source, supply and variability of DOM, surveys of the processes that mediate inputs to microbial food webs, and syntheses consolidating research findings provide a comprehensive review of what is known of DOM in freshwater. This book will be important to anyone interested in understanding the fundamental factors associated with DOM that control aquatic ecosystems."--BOOK JACKET.

The study of estuaries and coasts has seen enormous growth in recent years, since changes in these areas have a large effect on the food chain, as well as on the physics and chemistry of the ocean. As the coasts and river banks around the world become more densely populated, the pressure on these ecosystems intensifies, putting a new focus on environmental, socio-economic and policy issues. Written by a team of international expert scientists, under the guidance of Chief Editors Eric Wolanski and Donald McClusky, the Treatise on Estuarine and Coastal Science, Ten Volume Set examines topics in depth, and aims to provide a comprehensive scientific resource for all professionals and students in the area of estuarine and coastal science Most up-to-date reference for system-based coastal and estuarine science and management, from the inland watershed to the ocean shelf Chief editors have assembled a world-class team of volume editors and contributing authors Approach focuses on the physical, biological, chemistry, ecosystem, human, ecological and economics processes, to show how to best use multidisciplinary science to ensure earth's sustainability Provides a comprehensive scientific resource for all professionals and students in the area of estuarine and coastal science Features up-to-date chapters covering a full range of topics

Humic substances occur in all kinds of aquatic systems, but are particularly important in northern, coniferous areas. They strongly modify the aquatic ecosystems and also constitute a major problem in the drinking water supply. This volume covers all aspects of aquatic humic substances, from their origin and chemical properties, their effects on light and nutrient regimes and biogeochemical cycling, to their role regarding organisms, productivity and food web organization from bacteria to fish. Special emphasis is paid to carbon cycling and food web organization in humic lakes, but aspects of marine carbon cycling related to humus are treated as well.

Photoinduced processes, caused by natural sunlight, are key functions for sustaining all living organisms through production and transformation of organic matter (OM) in the biosphere. Production of hydrogen peroxide (H2O2) from OM is a primary step of photoinduced processes, because H2O2 acts as strong reductant and oxidant. It is potentially important in many aquatic reactions, also in association with photosynthesis. Allochthonous and autochthonous dissolved organic matter (DOM) can be involved into several photoinduced or biological processes. DOM subsequently undergoes several physical, chemical, photoinduced and biological processes, which can be affected by global warming. This book is uniquely structured to overview some vital issues, such as: DOM; H2O2 and ROOH; HO•; Degradation of DOM; CDOM, FDOM; Photosynthesis; Chlorophyll; Metal complexation, and Global warming, as well as their mutual interrelationships, based on updated scientific results.

A core text on principles, laboratory/field methodologies, and data interpretation for fluorescence applications in aquatic science, for advanced students and researchers.

Microbial extracellular enzymes are fundamental to the cycling of elements in aquatic systems. The regulation of these enzymatic reactions in oceans, lakes and streams is under complex multiple control by environmental factors and the metabolic capacities of different taxa and communities. While the environmental control of enzyme-mediated processes has been investigated for over 100 years, in recent years tremendous progress in techniques to characterize the metabolic potential of microbial communities (“omics” techniques) has been made, such as high-throughput sequencing and new analytical algorithms. This book explores the controls, activities, and biogeochemical consequences of enzymes in aquatic environments. It brings together experimental studies and fieldwork conducted with natural microbial communities in marine and freshwater ecosystems as well as physiological, biochemical and molecular studies on microbial communities in these environments, or species isolated from them. Additionally, the book contributes to the ongoing debate on the impact of anthropogenic climate change and pollution on microbes, extracellular enzymes and substrate turnover.

2017 has been an exciting year for our innovative open access journal Frontiers in Earth Science: many new articles have been published and are now indexed in Web of Science (ESCI), new sections have opened for submissions (including Solid Earth Geophysics), and our Editorial Board has been successfully leading the peer review process and providing comprehensive reviews to our authors. Have a look at our archive to read about the feeding habits of dinosaurs, human influence on in the African humid period, volcanic hazard models, or how glaciers flowing into the ocean surrounding Greenland have changed over time! Launched at the end of 2013, our Journal consists of several specialties whose number has increased with time and currently stands at 19, also including a few specialties co-listed in other fields (https://www.frontiersin.org/journals/earth-science#). The present selection is not exhaustive as new ones are being launched and/or are under consideration for development. This growth has been paralleled by a yearly increase in the number of contributions and the Editorial Board members, reflecting the health of the Journal. Now also indexed in Web of Science - Emerging Sources Citation Index (ESCI), Frontiers in Earth Science is ambitious to become the leading open access journal in its field. The idea of creating an Editor's Choice eBook has been in our minds for a while as we wanted to create an environment for the Chief Editors to highlight their choice of representative papers in the Journal - we are happy to present now our first edition. The eBook offers a quick, though representative, window into the different specialties, giving additional visibility to some of the most interesting studies published in 2016 and 2017. It provides a glimpse into the state of the art of Earth Science on the cusp of 2020. Earth Science studies the different spheres of the Earth (geosphere, atmosphere, hydrosphere and, partly, biosphere) and, as such, it provides a holistic perspective of our planet. This discipline, in addition to understanding our environment, enables us to face major natural challenges, such as improving the management of natural resources, promoting environmental sustainability and forecasting and managing natural hazards (Acocella, 2015, and references therein). On this basis, the contributions grouped in this eBook, even though appearing distinct in subject, methods, goal and impact, should be considered as different aspects of the same system. Indeed, the selection of these contributions aims to capture a multidisciplinary and common understanding of our planet, with its interconnected processes and challenges. It is important to note that, in many cases, it has not been easy to select a representative study per specialty, and thus the papers included in this eBook should therefore not be considered as the representative ones, but rather as a concise selection of key papers. We hope you enjoy reading our first edition of the Editor's Choice eBook! Jessica (Journal Manager), and Valerio (Field Chief Editor)