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Introduction The phenomenon of arsenite [As(III)] oxidation by aerobic bacteria was first reported by Green (1918), and the many subsequent discoveries made in this realm, most occurring over the past three decades, are the primary focus of this book. In contrast, the fact that select anaerobes can also achieve this feat...

Freshwater forested wetlands commonly occur in the lower Coastal Plain of the southeastern US with baldcypress (Taxodium distichum [L.] L.C. Rich.) and water tupelo (Nyssa aquatica L.) often being the dominant trees. Extensive anthropogenic activities combined with eustatic sea-level rise and land subsidence have caused widespread hydrological changes...

Evapotranspiration (ET) is an important component of the hydrologic budget because it režects the exchange of mass and energy between the soil-water-vegetation system and the atmosphere. Prevailing weather conditions inžuence potential or reference ET through variables such as radiation, temperature, wind, and relativity humidity. In addition to these weather variables,...

Due to its range expansion and potential ecological effects, Corbicula fluminea is considered one of the most important non-indigenous species (NIS) in aquatic ecosystems. Its presence since 2003 in the upstream area of Mondego estuary (oligohaline and mesohaline sectors) was studied during thirteen months, from December 2007 to December 2008....

The value of satellite remote sensing for drought monitoring was first realized more than two decades ago with the application of Normalized Difference Index (NDVI) data from the Advanced Very High Resolution Radiometer (AVHRR) for assessing the effect of drought on vegetation. Other indices such as the Vegetation Health Index...

Wind erosion following large wildfires on and around the INL Site is a recurrent threat to human health and safety, DOE operations and trafficability, and ecological and hydrological condition of the INL Site and down-wind landscapes. Causes and consequences of wind erosion are mainly known from warm deserts (e.g., Southwest...

Globally, riverine fish face many anthropogenic threats including riparian and flood plain habitat degradation, altered hydrology, migration barriers, fisheries exploitation, environmental (climate) change, and introduction of invasive species. Collectively, these threats have made riverine fishes some of the most threatened taxa on the planet. Although much effort has been devoted...

This book provides the reader with the comprehensive view necessary to understand and critically evaluate the design, implementation, and monitoring of phytoremediation at sites characterized by contaminated groundwater. Part I presents the historical foundation of the interaction between plants and groundwater, introduces fundamental groundwater concepts for plant physiologists, and...

Recent warming at high-latitudes has accelerated permafrost thaw in northern peatlands, and thaw can have profound effects on local hydrology and ecosystem carbon balance. To assess the impact of permafrost thaw on soil organic carbon (OC) dynamics, we measured soil hydrologic and thermal dynamics and soil OC stocks across a...

This chapter explores four water resources issues: 1) hydrologic variability, hazards, water supply and ecosystem preservation; 2) urban landscape design; 3) non-point source water quality, and 4) climate change, resiliency, and nonstationarity. It also considers what science, technology, and engineering practice may be needed in the coming decades to...

Coastal salt marsh and mangrove ecosystems are particularly vulnerable to changes in atmospheric CO2 concentrations and associated climate and climate-induced changes. We provide a review of the literature detailing theoretical predictions and observed responses of coastal wetlands to a range of climate change stressors, including CO2, temperature, rainfall, and sea-level...

An 800-year-long environmental history of Biscayne Bay, Florida, is reconstructed from ostracod faunal and shell geochemical (oxygen, carbon isotopes, Mg/Ca ratios) studies of sediment cores from three mudbanks in the central and southern parts of the bay. Using calibrations derived from analyses of modern Biscayne and Florida Bay ostracods, palaeosalinity...

The South Dover Bridge (SDB) corehole was drilled in October 2007 in Talbot County, Maryland. The main purpose for drilling this corehole was to characterize the Upper Cretaceous and Paleogene lithostratigraphy and biostratigraphy of the aquifers and confining units of this region. The data obtained from this core also will...

As part of the government response to the Deepwater Horizon blowout, a Well Integrity Team evaluated the geologic hazards of shutting in the Macondo Well at the seafloor and determined the conditions under which it could safely be undertaken. Of particular concern was the possibility that, under the anticipated high...

In this study the influence of geologic features related to sinkhole susceptibility was analyzed and the results were mapped for the region of Jefferson County, West Virginia. A model of sinkhole density was constructed using Geographically Weighted Regression (GWR) that estimated the relations among discrete geologic or hydrologic features and...

Dust is an abundant material on Mars, and there is strong evidence that it is a contributor to the rock record as “duststone,” analogous in many ways to loess on Earth. Although a common suite of dust formation mechanisms has operated on the two planets, fundamental differences in environments and...

Nonpoint source (NPS) pollution is tightly linked to land use activities that determine the sources and magnitudes of pollutant loadings to stream water. The pollutant loads may also be alleviated within reservoirs because of the physical interception resulting from changed hydrological regimes and other biochemical processes. It is important but...

Time‐lapse geophysical surveys using frequency‐domain electromagnetics (FDEM) can indirectly measure time‐varying hydrologic parameters such as fluid saturation or solute concentration. Monitoring of these processes provides insight into aquifer properties and the effectiveness of constructed controls (such as leachate interceptor trenches), as well as aquifer responses to natural or induced stresses....

Surface, unsaturated-zone, and saturated-zone hydrologic conditions at Yucca Mountain responded to past climate variations and are at least partly preserved by sediment, fossil, and mineral records. Characterizing past hydrologic conditions in surface and subsurface environments helps to constrain hydrologic responses expected under future climate conditions and improve predictions of repository...

MT3DMS is a three-dimensional multi-species solute transport model for solving advection, dispersion, and chemical reactions of contaminants in saturated groundwater flow systems. MT3DMS interfaces directly with the U.S. Geological Survey finite-difference groundwater flow model MODFLOW for the flow solution and supports the hydrologic and discretization features of MODFLOW. MT3DMS contains...

A unique 30-year streamwater chemistry data set from a mineralized alpine watershed with naturally acidic, metal-rich water displays dissolved concentrations of Zn and other metals of ecological concern increasing by 100–400% (400–2000 μg/L) during low-flow months, when metal concentrations are highest. SO4 and other major ions show similar increases. A lack...

Soil temperature changes after landscape disturbance impact hydrology, ecology, and geomorphology. This study used field measurements to examine wildfire and aspect effects on soil temperatures. Combustion of the litter and duff layers on north-facing slopes removed pre-fire aspect-driven soil temperature controls.Wildfire is one of the most significant disturbances in mountainous...

Statistical relationships between annual floods at 200 long-term (85–127 years of record) streamgauges in the coterminous United States and the global mean carbon dioxide concentration (GMCO2) record are explored. The streamgauge locations are limited to those with little or no regulation or urban development. The coterminous US is divided into...

No abstract available....

Potential climate change effects on aspects of conjunctive management of water resources can be evaluated by linking climate models with fully integrated groundwater-surface water models. The objective of this study is to develop a modeling system that links global climate models with regional hydrologic models, using the California Central Valley...