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The ascii grids represent regional probabilities that groundwater in a particular location will have dissolved oxygen (DO) concentrations less than selected threshold values representing anoxic groundwater conditions or will have dissolved manganese (Mn) concentrations greater than selected threshold values representing secondary drinking water-quality contaminant levels (SMCL) and health-based screening levels (HBSL) for water quality. The probability models were constrained by the alluvial boundary of the Central Valley to a depth of approximately 300 meters (m). We utilized prediction modeling methods, specifically boosted regression trees (BRT) with a Bernoulli error distribution within a statistical learning...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Boosted Regression Trees,
California,
Central Valley, California,
Domestic Well Water Use,
Drinking Water Use,
Abstract (from http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-14-00197.1): Using the hybrid downscaling technique developed in part I of this study, temperature changes relative to a baseline period (1981–2000) in the greater Los Angeles region are downscaled for two future time slices: midcentury (2041–60) and end of century (2081–2100). Two representative concentration pathways (RCPs) are considered, corresponding to greenhouse gas emission reductions over coming decades (RCP2.6) and to continued twenty-first-century emissions increases (RCP8.5). All available global climate models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) are downscaled to provide likelihood and uncertainty estimates....
Categories: Publication;
Types: Citation;
Tags: CMIP5,
California,
Data Visualization & Tools,
Science Tools for Managers,
Southwest CASC,
Quaking aspen (Populus tremuloides) woodlands are expected to be sensitive to climate change, and have declined in parts of the West. Great Basin mountain ranges may be near the limits of aspen’s climatic threshold, in terms of temperature and aridity, and thus are particularly vulnerable to climate change. Birds associating with aspen are likely to undergo regional population fluctuations and changes in distribution as a result of changes in aspen availability or distribution. Thus, understanding the habitat relationships of avian communities in aspen and other montane cover types is important for tracking the impacts of future landscape change. The mountainous terrain of the Humboldt-Toiyabe National Forest in...
Categories: Data,
Publication;
Types: Citation;
Tags: EARTH SCIENCE > LAND SURFACE > LANDSCAPE,
LCC Network Science Catalog,
Report,
aspen woodland,
biota,
Emerging applications of ecosystem resilience and resistance concepts in sagebrush ecosystems allow managers to better predict and mitigate impacts of wildfire and invasive annual grasses. Soil temperature and moisture strongly influence the kind and amount of vegetation, and consequently, are closely tied to sagebrush ecosystem resilience and resistance (Chambers et al. 2014). Soil taxonomic temperature and moisture regimes can be used as indicators of resilience and resistance at landscape scales to depict environmental gradients in sagebrush ecosystems that range from cold/cool-moist sites to warm-dry sites. We aggregated soil survey spatial and tabular data to facilitate broad-scale analyses of resilience and...
Categories: Data,
Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: California,
Colorado,
EARTH SCIENCE > LAND SURFACE > LANDSCAPE,
Greater sage-grouse,
Greater sage-grouse,
The exotic annual grass Bromus tectorum (cheatgrass) dominates vast acreages of rangeland in the western USA, leading to increased fire frequency and ecosystem degradation that is often irreversible. Episodic regeneration failure (“die-off”) has been observed in cheatgrass monocultures and can have negative ecosystem consequences, but can also provide an opportunity for restoration of native species and ecological function within the imperiled sagebrush steppe ecosystem. Proximate causes of cheatgrass die-off are uncertain, although several taxa of fungal soil pathogens have been implicated. Die-off occurrence is stochastic and can occur in remote areas. Thus, developing remote sensing indicators that are repeatable...
Categories: Data,
Publication;
Types: Citation;
Tags: Academics & scientific researchers,
California,
Cheatgrass,
Completed,
EARTH SCIENCE > LAND SURFACE > LANDSCAPE,
The sagebrush steppe is a patchwork of species and subspecies occupying distinctenvironmental niches across the intermountain regions of western North America. These ecosystems facedegradation from disturbances and exotic weeds. Using sagebrush seed that is matched to its appropriateniche is a critical component to successful restoration, improving habitat for the threatened greater sage-grouse and other species. The need for restoration is greatest in basin habitats composed of two subspecies:diploid basin big sagebrush (A. tridentatasubsp.tridentata) and tetraploid Wyoming big sagebrush (subsp.wyomingensis). In this study we assess seed weights across five subspecies-cytotype groups of bigsagebrush and examine...
Categories: Data,
Publication;
Types: Citation;
Tags: Academics & scientific researchers,
Artemisia tridentata,
California,
Completed,
EARTH SCIENCE > LAND SURFACE > LANDSCAPE,
Invasions by exotic grasses, particularly annuals, rank among the most extensive and intensive ways that humans are contributing to the transformation of the earth’s surface. The problem is particularly notable with a suite of exotic grasses in the Bromus genus in the arid and semiarid regions that dominate the western United States, which extend from the dry basins near the Sierra and Cascade Ranges across the Intermountain Region and Rockies to about 105° longitude. This genus includes approximately 150 species that have a wide range of invasive and non-invasive tendencies in their home ranges and in North America. Bromus species that became invasive upon introduction to North America in the late 1800’s, such...
Categories: Data,
Publication;
Types: Citation;
Tags: California,
EARTH SCIENCE > LAND SURFACE > LANDSCAPE,
Great Basin,
Idaho,
LCC Network Science Catalog,
Wind erosion and aeolian transport processes are under studied compared to rainfall-induced erosion and sediment transport on burned landscapes. Post-fire wind erosion studies have predominantly focused on near-surface sediment transport and associated impacts such as on-site soil loss and site fertility. Downwind impacts, including air quality degradation and deposition of dust or contaminants, are also likely post-fire effects; however, quantitative field measurements of post-fire dust emissions are needed for assessment of these downwind risks. A wind erosion monitoring system was installed immediately following a desert sagebrush and grass wildfire in southeastern Idaho, USA to measure wind erosion from the burned...
Categories: Data,
Publication;
Types: Citation;
Tags: California,
EARTH SCIENCE > LAND SURFACE > LANDSCAPE,
Great Basin,
Idaho,
LCC Network Science Catalog,
This shapefile represents habitat suitability categories (High, Moderate, Low, and Non-Habitat) derived from a composite, continuous surface of sage-grouse habitat suitability index (HSI) values for Nevada and northeastern California formed from the multiplicative product of the spring, summer, and winter HSI surfaces.
Categories: Data,
Publication;
Types: Citation,
Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: California,
Great Basin,
Greater Sage-Grouse,
Habitat,
Nevada,
Dr. Richard Janda of the USGS began a channel monitoring program in Redwood Creek in northern coastal California in 1973. The USGS continued this work through 2013, when the Research Geologist, Dr. Mary Madej retired. This effort produced 40 years of channel change data in rivers that were disrupted by severe erosion following timber harvest of old-growth redwood forests, a portion of the program's data (plus 1953 data) has been preserved in this data release. Original field surveys documented bank erosion, aggradation, and degradation at 60 cross-sectional transects at annual or biannual timesteps. Three river reaches also have long-term longitudinal channel bed surveys which document the distribution and development...
Categories: Data,
Publication;
Types: Citation,
Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: 44 Creek,
Bond Creek,
California,
Dolason Creek,
Elam Creek,
Electricity-generating wind turbines are an attractive energy source because they are renewable and produce no emissions. However, they have at least two potentially damaging ecological effects. Their rotating blades are hazardous to raptors which occasionally fly into them. And wind turbines are very noisy when active, a feature that may interfere with the lives of animals beneath them. We studied California ground squirrels (Spermophilus beecheyi) in the Altamont Pass Wind Resource Area of Northern California. These squirrels emit vocalizations that alert others to the presence of a predator, and so may be forced to compensate for turbine noise by modifying antipredator behavior. We compared the antipredator behavior...
Categories: Publication;
Types: Citation;
Tags: California,
Turbine,
antipredator,
behavior,
effects,
This raster represents a continuous surface of sage-grouse habitat suitability index (HSI) values for Nevada during the winter season, and is a surrogate for habitat conditions during periods of cold and snow.
Categories: Data,
Publication;
Types: Citation,
Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: California,
Great Basin,
Greater Sage-Grouse,
Habitat,
Nevada,
The baseline map of the Butte Basin, the representative basin from the Central Valley, was generated first by delineating the extent of the landscape to be modeled, in agreement with the basin boundaries identified by the Central Valley Joint Venture.The Butte Basin (CV) encompasses a region approximately 44km x 64 km, and the map used contains 10,698 individual habitat patches and 179,964 acres of possible foreageable area. Patch habitat types were identified by a combination of USDA CropScape data (to identify agricultural habitat patches including rice and corn) and other local mapping data made available through collaboration with USGS. Habitat flood schedules were generated using the Water Evaluation and Planning...
Categories: Data,
Publication;
Types: Citation;
Tags: Butte,
California,
Central Valley aquifer system,
Colusa,
Glenn,
Synopsis: Wildfires can negatively affect water quality by altering watershed hydrology and increasing sediment and nutrient delivery to surface waters. The Angora Fire (summer of 2007) was the largest and most severe wildfire in recent history within the Lake Tahoe basin of the Sierra Nevada. The fire burned 839 ha within the watershed (56% of the total watershed area), with 22% of the watershed affected by a high severity burn. To determine the watershed response to fire and assess the potential for downstream impacts of nutrient and sediment delivery to Lake Tahoe, the post-fire hydrology and stream water chemistry was monitored for 2 years at four locations along the length of Angora Creek, a perennial stream...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: California,
Land use configuration,
Natural cover amount,
Sierra Nevada woodlands,
fire,
How climate constrains species’ distributions through time and space is an important question in the context of conservation planning for climate change. Despite increasing awareness of the need to incorporate mechanism into species distribution models (SDMs), mechanistic modeling of endotherm distributions remains limited in this literature. Using the American pika (Ochotona princeps) as an example, we present a framework whereby mechanism can be incorporated into endotherm SDMs. Pika distribution has repeatedly been found to be constrained by warm temperatures, so we used Niche Mapper, a mechanistic heat-balance model, to convert macroclimate data to pika-specific surface activity time in summer across the western...
Categories: Data,
Publication;
Types: Citation;
Tags: American pika,
California,
Completed,
EARTH SCIENCE > LAND SURFACE > LANDSCAPE,
Great Basin,
Alien grass invasions in arid and semi-arid ecosystems are resulting in grass-fire cycles and ecosystem-level transformations that severely diminish ecosystem services. Our capacity to address the rapid and complex changes occurring in these ecosystems can be enhanced by developing an understanding of the environmental factors and ecosystem attributes that determine resilience of native ecosystems to stress and disturbance, and resistance to invasion. Cold desert shrublands occur over strong environmental gradients and exhibit significant differences in resilience and resistance. They provide an excellent opportunity to increase our understanding of these concepts. Herein, we examine a series of linked questions...
Categories: Data,
Publication;
Types: Citation;
Tags: California,
EARTH SCIENCE > LAND SURFACE > LANDSCAPE,
Great Basin,
Idaho,
LCC Network Science Catalog,
The estimation of mass concentration of suspended solids is one of the properties needed to understand the characteristics of sediment transport in bays and estuaries. However, useful measurements or estimates of this property are often problematic when employing the usual methods of determination from collected water samples or optical sensors. Analysis of water samples tends to undersample the highly variable character of suspended solids, and optical sensors often become useless from biological fouling in highly productive regions. Acoustic sensors, such as acoustic Doppler current profilers that are now routinely used to measure water velocity, have been shown to hold promise as a means of quantitatively estimating...
Categories: Publication;
Types: Citation;
Tags: California,
San Francisco Bay,
acoustic Doppler current profiler,
acoustic backscatter intensity,
suspended solids concentration
The estimation of mass concentration of suspended solids is one of the properties needed to understand the characteristics of sediment transport in bays and estuaries. However, useful measurements or estimates of this property are often problematic when employing the usual methods of determination from collected water samples or optical sensors. Analysis of water samples tends to undersample the highly variable character of suspended solids, and optical sensors often become useless from biological fouling in highly productive regions. Acoustic sensors, such as acoustic Doppler current profilers that are now routinely used to measure water velocity, have been shown to hold promise as a means of quantitatively estimating...
Categories: Publication;
Types: Citation;
Tags: California,
San Francisco Bay,
acoustic Doppler current profiler,
acoustic backscatter intensity,
suspended solids concentration
Synopsis: Because recent bark beetle population eruptions have exceeded the frequencies, impacts, and ranges documented during the previous 125 years, researchers have been prompted to determine what factors trigger broad scale outbreaks, and how do these factors interact? How do human activities, such as forest management, alter these interactions, and thus the frequency, extent, severity, and synchrony of outbreaks? Extensive host tree abundance and susceptibility, concentrated beetle density, favorable weather, optimal symbiotic associations, and escape from natural enemies must occur jointly for beetles to surpass a series of thresholds and exert widespread disturbance. Eruptions occur when key thresholds are...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Alaska,
Alberta,
Arizona,
British Columbia,
California,
Habitat condition, both acres flooded and timing of inundation, were determined using remote sensing images from Landsat 5 and 8 for the Lower Klamath Basin, the representative basin for the southern Oregon and northeast California (SONEC) region. The dataset includes proportional water coverage (acres) for 8,825 distinct patches in Lower Klamath over 6 different time periods (1984-89; 1990-94; 1995-99; 2000-04; 2005-09; 2010-16), with a total of 368,301 acres of possibly foreageable land.
Categories: Data,
Publication;
Types: Citation,
Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: California,
Klamath,
Lower Klamath,
Modoc,
Oregon,
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