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The overall objective of this project is to determine the role of chemical processes associated with dissolved organic carbon (DOC) on the transport and reactivity of both naturally occurring and anthropogenic compounds. Defining the roles of DOC in environmental and geochemical processes is critical to understanding the nature and quality of the Nation’s water resources, and is important for future management of these resources. This field of study has increased in relevancy as numerous environmental problems have been linked to processes involving organic matter. My project attempts to meet these needs by focusing on the chemical mechanisms controlling the fate, transport, and reactivity of naturally occurring...
The overarching objective of this Project is to determine how and why biogeochemical cycles of macronutrients (i.e. C, Fe, S, etc…) and those for certain trace contaminants (e.g. Hg, Se, As, etc…) covary at the ecosystem and regional scales. General approaches to this end include: comparing and contrasting key biogeochemical pathways both within the sub-habitats of a given ecosystem and among systems that involve a wide range of land-use practices, fostering collaborations with other USGS and non-USGS scientists on projects that are regional in scope, have a fundamental biogeochemical/microbiological focus, and that balance basic environmental research with management / society ‘needs-driven’ research expanding...
Many persistent organic compounds are hazardous to human and ecological health. The transport characteristics of these compounds across environmental phases are strongly influenced by adsorption and partition interactions with the individual phases. Quantification of process rates and partition constants of organic pollutants in air, water, soil, and biota is an important step in defining the level of organic contaminants in environmental systems and their potential impact on environmental quality. Project objectives are to delineate and quantify processes affecting the movement and distribution of persistent organic compounds in hydrogeologic systems. Specifically: (1) determine the sorptive capacity of soil and...
Ground-Water solute-transport simulation modeling is an important tool that aids in the analysis of ground-water contamination problems, both actual and potential. Accidental spills, leakage, and waste disposal operations can lead to ground-water contamination. The ability to analyze and predict the movement of solutes in ground-water systems is necessary to assess the effects of a contamination situation or properly design a waste-disposal operation. Laboratory experiments are essential to understanding geochemical reactions in the field and for obtaining the necessary reaction coefficients and rate constants used in transport models. Simulation modeling also is used to compare alternative strategies for aquifer...
Delineate and quantify processes affecting the movement and distribution of pollutants in hydrogeologic systems. (1) Determine the sorptive capacity of soil and sediment for compounds of interest that are dissolved in water; (2) identify the roles of soil and sediment organic matter and mineral components in sorption of pollutants; (3) examine the interaction of natural organic matter with mineral surfaces and its consequent effect on sorption of compounds of interest; (4) characterize the effect of dissolved organic matter on the solubility and mobility of organic contaminants in natural water; and (5) determine the characteristics of pyrogenic soil components (black carbon) and its effects on fate and transport...
Uranium mill tailings and related forms of low-level radioactive waste contain elevated contents of naturally occurring radionuclides that have been brought to the surface, processed for the recovery of uranium and/or other components and then disposed of in near-surface impoundments. The long-term fate of the tailings and their constituents will be determined by surficial earth processes. Project objectives are to study the chemical form in which radionuclides and selected stable elements are retained in surficial earth materials, particularly uranium mill tailings, and to identify processes operating in natural aqueous and terrestrial systems that may influence the transport of these constituents from these earth...
Categories: Project;
Tags: Contaminants,
Isotopic Tracers,
Microbiology (Activity and Transport),
Radioisotopes
The diversion of freshwater from the Mississippi River is intended to mitigate saltwater intrusion from the Gulf of Mexico and to lessen the concomitant loss of wetland areas. Though effective, freshwater diversion can affect wildlife and habitat; therefore, prediversion and postdiversion data collections are necessary to identify effects. The Davis Pond freshwater diversion area is located between the Mississippi River and Bayou Lafourche and extends to Barataria Bay Basin, Louisiana. Results and interpretations from the prediversion biomonitoring done in 2001- which included data on fish, eagles, and bivalves - are presented in the U.S. Geological Survey (USGS) Scientific Investigations Report 2008-5067, "Davis...
The diversion of freshwater from the Mississippi River is intended to mitigate saltwater intrusion from the Gulf of Mexico and to lessen the concomitant loss of wetland areas. Though effective, freshwater diversion can affect wildlife and habitat; therefore, prediversion and postdiversion data collections are necessary to identify effects. The Davis Pond freshwater diversion area is located between the Mississippi River and Bayou Lafourche and extends to Barataria Bay Basin, Louisiana. Results and interpretations from the prediversion biomonitoring done in 2001 - which included data on fish, eagles, and bivalves - are presented in the U.S. Geological Survey (USGS) Scientific Investigations Report 2008-5067, "Davis...
Largemouth base histological development and transcriptomic changes in gonad tissue after early life stage exposure to Atrazine (1-Chloro-3-ethylamino-5-isopropylamino-2,4,6-triazine) or the model estrogen 17α-ethinylestradiol.
The datasets stored in this folder summarize polycyclic aromatic hydrocarbon (PAH) reference data, and values collected from Brown Pelican nestlings and breeding adults from 2013-2015 in the Northern Gulf of Mexico at 9 breeding colonies from Texas to the Florida Panhandle. Evaluated PAH included 1,3-dimethylnaphthalene, 1,5-dimethylnaphthalene, 1-methylfluorene, 2,3,5-trimethylnaphthalene, 2,6-dimethylnaphthalene, 2-methylnaphthalene, 3-methylphenanthrene, 9-methylphenanthrene, Acenaphthalene, Acenapthene, Anthracene, Benzo(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, Benzo(g,h,i)perylene, Benzo(k)fluoranthene, Chrysene, Dibenz(a,h)anthracene, Fluoranthene, Fluorene, Indeno(1,2,3-cd)pyrene, Naphthalene,...
Our approach will include sampling a wide range of habitats and environmental conditions throughout the middle and lower Pecos River basin, across an 18 month time-span to account for seasonal and phenological events. We will utilize a suite of univariate and multivariate statistical techniques to relate occurrence and density of golden alga to environmental factors and other co-occurring organisms. The proposed research will benefit managers of the Pecos River, of its associated reservoirs and unique habitats (sinkholes on the Bottomless Lakes State Park and Bitter Lakes National Wildlife Refuge), and of its resident aquatic biota by identifying specific water quality attributes that promote golden alga bloom development...
Categories: Data,
Project;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2011,
CONTAMINANTS,
CONTAMINANTS,
Data Acquisition and Development,
Datasets/Database,
This project seeks to quantify, predict, and project the relative role of plant physiology, among other ecosystem drivers, on carbon, nutrient, and trace-metal biogeochemistry. Approaches span landscape-to-molecular scales as necessary to understand how human and stochastic alterations of wetland structure influence wetland function. Research sites represent a wide range of salinity and management conditions, from rice agriculture to coastal and restored wetlands. Primary goals include evaluating management and modeling approaches to quantify wetland carbon sequestration, greenhouse gas budgets and/or mercury methylation and export.
Categories: Project;
Tags: Biogeochemistry,
Carbon Cycling and Sequestration,
Climate Change,
Contaminants,
Ecology,
The Reaction-Transport Modeling Group provides environmental managers and policy makers with the understanding and tools needed to predict how decisions made today can improve the amount of clean water available to both society and to nature in the future. In support of the project goals, I have developed the Water, Energy, and Biogeochemical Model (WEBMOD). WEBMOD integrates the latest understanding of hydrologic processes with the full gamut of geochemical simulations available in PHREEQC to simulate conservative and reactive transport of solutes that cycle between the atmosphere, the soils, and bedrock.
My primary objective is to understand the function of the benthic community at various spatial scales with the goal of understanding and modeling the benthic community processes at the ecosystem level. Specifically, my goals are to (1) explore ecological and physical processes that are affected by the benthic community and that effect benthic community composition and function; (2) look at these processes at a variety of time scales (days to seasons and inter-annual time scales) so that hydrologic, climate, and exotic species effects on benthic communities and their ecosystems can be understood; (3) develop habitat and energetics models of dominant members of the benthic community that can be dynamically linked...
Categories: Project;
Tags: Aquatic Habitat,
Contaminants,
Ecology,
Estuaries and Near-Shore Environments
The responsible use of our Nation's ground-water resources requires an ability to predict changes in water quality as a result of human impacts. Prediction of chemical quality in the ground-water environment depends on a detailed understanding of both chemical and hydrologic processes. To determine the spatial and temporal variability of ground-water quality, it is necessary to identify reactions occurring in the system, to define their kinetic and thermodynamic properties, and to determine how the configuration of the hydrologic regime influences ground-water quality. The objectives of this project are to: (1) identify chemical reactions in ground-water systems using observed chemical and isotopic composition of...
This report surveys the definitions of reserve services used in several countries and regions of Europe and the United States that have implemented competitive electricity markets. It also compares the technical specifications of these services. The systems considered are Great Britain, PJM, California, Spain, The Netherlands, Germany, France, Belgium as well as UCTE as a whole.
Categories: Publication;
Types: Citation;
Tags: avian fatalities,
avian mortality,
collisions,
communication towers,
contaminants,
The diversion of freshwater from the Mississippi River is intended to mitigate saltwater intrusion from the Gulf of Mexico and to lessen the concomitant loss of wetland areas. Though effective, freshwater diversion can affect wildlife and habitat; therefore, prediversion and postdiversion data collections are necessary to identify effects. The Davis Pond freshwater diversion area is located between the Mississippi River and Bayou Lafourche and extends to Barataria Bay Basin, Louisiana. Results and interpretations from the prediversion biomonitoring done in 2001- which included data on fish, eagles, and bivalves - are presented in the U.S. Geological Survey (USGS) Scientific Investigations Report 2008-5067, "Davis...
The diversion of freshwater from the Mississippi River is intended to mitigate saltwater intrusion from the Gulf of Mexico and to lessen the concomitant loss of wetland areas. Though effective, freshwater diversion can affect wildlife and habitat; therefore, prediversion and postdiversion data collections are necessary to identify effects. The Davis Pond freshwater diversion area is located between the Mississippi River and Bayou Lafourche and extends to Barataria Bay Basin, Louisiana. Results and interpretations from the prediversion biomonitoring done in 2001- which included data on fish, eagles, and bivalves - are presented in the U.S. Geological Survey (USGS) Scientific Investigations Report 2008-5067, "Davis...
Coastal communities are uniquely vulnerable to sea-level rise and severe storms such as hurricanes. These events enhance the dispersion and concentration of natural and anthropogenic chemicals and pathogenic microorganisms that could adversely affect the health and resilience of coastal communities and ecosystems in subsequent years. The U.S. Geological Survey has developed the Sediment-Bound Contaminant Resiliency and Response (SCoRR) strategy to define baseline and post-event sediment-bound environmental health stressors. These data document the results from protein phosphatase 2A screening of extracts for selected stations in the northeastern U.S. during the 2015 pilot implementation of the SCoRR strategy in...
These catalogs serve to identify known locations of mineral extraction and exploration activities discussed for the purpose of eventually discovering these data through the Mines web map application. These tables of information will reduce data entry time through use of queries to generate records. They also help identify properties without a clear location for efficient discussion with the original authors.
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