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Lake Powell retains most of the phosphorus that it receives, leading to downstream phosphorus limitation. These data were compiled to examine controls on phosphorus cycling below Lake Powell in the Colorado River and from storm inputs from the Paria River. Objectives of our study were to determine how several forms of phosphorus, both organic and inorganic, were cycled under varying dissolved oxygen concentrations and pH, reflecting the range of values observed in the river over the years. These data represent nitrogen, phosphorus, calcium, and carbon concentrations, water quality parameters (pH, dissolved oxygen, temperature), sediment composition, total protein, and extracellular enzyme activity (alkaline phosphatase)....
These data were compiled to demonstrate new predictive mapping approaches and provide comprehensive gridded 30-meter resolution soil property maps for the Colorado River Basin above Hoover Dam. Random forest models related environmental raster layers representing soil forming factors with field samples to render predictive maps that interpolate between sample locations. Maps represented soil pH, texture fractions (sand, silt clay, fine sand, very fine sand), rock, electrical conductivity (ec), gypsum, CaCO3, sodium adsorption ratio (sar), available water capacity (awc), bulk density (dbovendry), erodibility (kwfact), and organic matter (om) at 7 depths (0, 5, 15, 30, 60, 100, and 200 cm) as well as depth to restrictive...
Research examining organic-matter hosted porosity has significantly increased during the last ten years due to greater focus on understanding hydrocarbon migration and storage in source-rock reservoirs, and technological advances in scanning electron microscopy (SEM) capabilities. The examination of nanometer-scale organic-matter hosted porosity by SEM requires the preparation of exceptionally flat geologic samples beyond the abilities of traditional mechanical polishing which can deform or otherwise obscure organic surfaces. To meet this demand, broad ion beam (BIB) milling was introduced as a sample preparation technique for SEM petrographic analysis of geologic samples. But like with any sample preparation technique,...
Categories: Data;
Tags: Colorado,
Energy Resources,
England,
Geochemistry,
USGS Science Data Catalog (SDC),
Presented by Don Spalinger & Nathan WolfThis seminar focuses on our concepts of regulation of nutrient flows through tundra ecosystems and the effect that climate (or weather) has on these processes. Nutrient flow and climate, in turn, should regulate plant phenology and production, and thus caribou behavior and nutrition. We will present some ideas for assessing the landscape patterns of these processes and monitoring their impacts. Finally, we will provide examples of such assessment and monitoring processes from our work in Western Alaska over the past two years.
Categories: Data;
Tags: ALPINE/TUNDRA,
ALPINE/TUNDRA,
CARBON,
CARBON,
CARBON CYCLE/CARBON BUDGET MODELS,
Here we report optical data collected as part of a collaborative study between USGS Pennsylvania Water Science Center, Pennsylvania Department of Environmental Protection and Water Mission Area Proxies Project. The optical measurements reported here were collected to aide in the characterization of water sources and mixtures and establish proxies (surrogates) for per- and poly-fluorinated alkyl substances within the Neshaminy Creek basin. Data are compiled into three tables: 1) full fluorescence spectra in vectorized format, 2) full absorbance spectra, and 3) summary file of commonly extracted optical indicators and field-based sensor arrays.
Categories: Data;
Tags: California,
California Water Science Center,
Environmental Health,
Geochemistry,
Organic Matter Research Lab,
The tundra biome is the dominant terrestrial ecosystem of the circumpolar north, and its fate in a rapidly changing climate is of high scientific and socioeconomic concern. One of those concerns is that the majority of caribou herds throughout the circumpolar north are declining, perhaps as a result of climate change. The principal objective of this research is to reveal the connections between soil nutrient cycling, forage quality and caribou habitat selection. This framework is underpinned by the concept that tundra ecosystem productivity is ultimately driven by the thermodynamics of the system induced by climate.
Categories: Data,
Publication;
Types: Citation;
Tags: ALPINE/TUNDRA,
ALPINE/TUNDRA,
CARBON,
CARBON,
CARBON CYCLE/CARBON BUDGET MODELS,
The use of field-deployable fluorescence sensors to better understand dissolved organic matter concentrations and composition has grown immensely in recent years. Applications of these sensors to critical monitoring efforts have also grown to encompass post-fire monitoring, wastewater tracking, and use as a proxy for various contaminants. Despite the growth, it is well known that these sensors are subject to various interferences and require corrections for temperature, turbidity, and concentration effects. Although temperature corrections are widely applicable across sensors, the turbidity and concentration corrections can be site-specific and/or sensor-specific. The corrections can even be subject to changes in...
Categories: Data;
Tags: DOC,
USGS California Water Science Center,
USGS Science Data Catalog (SDC),
Water Quality,
biota,
The tundra biome is the dominant terrestrial ecosystem of the circumpolar north, and its fate in a rapidly changing climate is of high scientific and socioeconomic concern. One of those concerns is that the majority of caribou herds throughout the circumpolar north are declining, perhaps as a result of climate change. The principal objective of this research is to reveal the connections between soil nutrient cycling, forage quality and caribou habitat selection. This framework is underpinned by the concept that tundra ecosystem productivity is ultimately driven by the thermodynamics of the system induced by climate. In winter, soil microbial processes drive N mineralization and thus N available for plant growth...
Categories: Data,
Project;
Tags: ALPINE/TUNDRA,
ALPINE/TUNDRA,
CARBON,
CARBON,
Conservation Planning,
These data were released prior to the October 1, 2016 effective date for the USGS’s policy dictating the review, approval, and release of scientific data as referenced in USGS Survey Manual Chapter 502.8 Fundamental Science Practices: Review and Approval of Scientific Data for Release. Fanno Creek is a tributary to the Tualatin River and flows though parts of the southwest Portland metropolitan area. The stream is heavily influenced by urban runoff and shows characteristic flashy streamflow and poor water quality commonly associated with urban streams. This data set represents the geomorphic floodplain as derived from light detection and ranging (LiDAR) data and aerial photographic imagery. The floodplain represents...
These data were compiled to demonstrate new predictive mapping approaches and provide comprehensive gridded 30-meter resolution soil property maps for the Colorado River Basin above Hoover Dam. Random forest models related environmental raster layers representing soil forming factors with field samples to render predictive maps that interpolate between sample locations. Maps represented soil pH, texture fractions (sand, silt clay, fine sand, very fine sand), rock, electrical conductivity (ec), gypsum, CaCO3, sodium adsorption ratio (sar), available water capacity (awc), bulk density (dbovendry), erodibility (kwfact), and organic matter (om) at 7 depths (0, 5, 15, 30, 60, 100, and 200 cm) as well as depth to restrictive...
The tundra biome is the dominant terrestrial ecosystem of the circumpolar north, and its fate in a rapidly changing climate is of high scientific and socioeconomic concern. One of those concerns is that the majority of caribou herds throughout the circumpolar north are declining, perhaps as a result of climate change. The principal objective of this research is to reveal the connections between soil nutrient cycling, forage quality and caribou habitat selection.
Categories: Data;
Tags: ALPINE/TUNDRA,
ALPINE/TUNDRA,
CARBON,
CARBON,
CARBON CYCLE/CARBON BUDGET MODELS,
Here, we present data supporting temporal variability and sources of PFAS in the Rio Grande through an arid urban area using high-frequency sampling and novel samplers. Data are compiled into two tables: 1) full fluorescence spectra in vectorized format, and 2) summary file of concentrations of total dissolved nitrogen and commonly extracted field-based sensor arrays. Data are reported from two sites at Rio Grande, New Mexico during a 24-hour collection period. Two field blanks, one field replicate, and two laboratory replicates are reported for 26 environmental samples.
Categories: Data;
Tags: California,
Organic Matter Research Lab,
Sacramento,
TDN,
USGS Science Data Catalog (SDC),
These data were released prior to the October 1, 2016 effective date for the USGS’s policy dictating the review, approval, and release of scientific data as referenced in USGS Survey Manual Chapter 502.8 Fundamental Science Practices: Review and Approval of Scientific Data for Release. In 2010, the U.S. Geological Survey (USGS) began investigating the sources and sinks of organic matter in Fanno Creek, a tributary of the Tualatin River, Oregon. Organic matter, more specifically organic carbon, is abundant in Fanno Creek and has been tied to a variety of water-quality concerns. Since organic carbon is commonly found in the fine-grained, organic-rich sediment covering much of the watershed, developing a better understanding...
These data were released prior to the October 1, 2016 effective date for the USGS’s policy dictating the review, approval, and release of scientific data as referenced in USGS Survey Manual Chapter 502.8 Fundamental Science Practices: Review and Approval of Scientific Data for Release. Fanno Creek is a tributary to the Tualatin River and flows though parts of the southwest Portland metropolitan area. The stream is heavily influenced by urban runoff and shows characteristic flashy streamflow and poor water quality commonly associated with urban streams. This data set represents the locations where solid samples were collected.
Optical sensors measuring fluorescence of dissolved organic matter (fDOM) are increasingly used in water quality studies because they provide proxy measurements for a variety of contaminants and constituents of concern including metals and wastewater effluent. Similarly, sensors measuring fluorescence of chlorophyll (fChl) and phycocyanin (fPC) have gained popularity to measure phytoplankton concentration, biomass, and even primary productivity. Optical sensors require calibration using a calibration standard solution which is diluted from a working stock solution. However, preparation of stock solutions is challenging because they are difficult to prepare accurately, need to be prepared in a laboratory setting,...
Categories: Data;
Tags: California,
California Water Science Center,
Organic Matter Research Lab,
Sacramento,
USGS Science Data Catalog (SDC),
The tundra biome is the dominant terrestrial ecosystem of the circumpolar north, and its fate in a rapidly changing climate is of high scientific and socioeconomic concern. One of those concerns is that the majority of caribou herds throughout the circumpolar north are declining, perhaps as a result of climate change. The principal objective of this research is to reveal the connections between soil nutrient cycling, forage quality and caribou habitat selection.
Categories: Data;
Tags: ALPINE/TUNDRA,
ALPINE/TUNDRA,
CARBON,
CARBON,
CARBON CYCLE/CARBON BUDGET MODELS,
The caribou populations of southwest Alaska have declined precipitously over the past decade or more, and the total population of this expansive region currently is 80% below the populations of the late 90’s to early 2000’s. This research is a collaborative effort among the principal managers of this resource to directly address the causes of this decline.The goals of this project was to mechanistically link climate, soil N cycling, plant morphological and nutritional phenology, and caribou population dynamics, by collecting high-quality information to knit together ecosystem function across several trophic levels and at a range of spatial and temporal scales.
Categories: Data;
Tags: ALPINE/TUNDRA,
ALPINE/TUNDRA,
CARBON,
CARBON,
CARBON CYCLE/CARBON BUDGET MODELS,
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