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Five principal components are used to represent the climate variation in an original set of 12 composite climate variables reflecting complex precipitation and temperature gradients. The dataset provides coverage for future climate (defined as the 2040-2070 normal period) under the RCP4.5 emission scenarios. Climate variables were chosen based on their known influence on local adaptation in plants, and include: mean annual temperature, summer maximum temperature, winter minimum temperature, annual temperature range, temperature seasonality (coefficient of variation in monthly average temperatures), mean annual precipitation, winter precipitation, summer precipitation, proportion of summer precipitation, precipitation...
The recognition and characterization of aeolian dust in soil contribute to a better understanding of landscape and ecosystem dynamics of drylands. Results of this study show that recently deposited dust, sampled in isolated, mostly high-ground settings, is chemically and mineralogically similar on varied geologic substrates over a large area (15 000 km2) in the Mojave Desert. The silt-plus-clay fraction (fines) on these isolated surfaces is closely alike in magnetic-mineral composition, in contrast to greatly dissimilar magnetic compositions of rock surfaces of vastly different lithologies, on which the fines have accumulated. The fines, thus, are predominantly deposited dust. The amounts of potential nutrients...
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Climate Distance Mapper is an interactive web mapping application designed to facilitate informed seed sourcing decisions and to aid in directing regional seed collections. Implemented as a shiny web application (Chang et al. 2017), Climate Distance Mapper is hosted on the web at: https://usgs-werc-shinytools.shinyapps.io/Climate_Distance_Mapper/. The application is designed to guide restoration seed sourcing in the desert southwest by allowing users to interactively match seed sources with restoration sites climatic differences – in the form of multivariate climate distance values – between restoration sites and the surrounding landscape. Climatic distances are based on a combination of variables likely to influence...
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Five principal components are used to represent the climate variation in an original set of 12 composite climate variables reflecting complex precipitation and temperature gradients. The dataset provides coverage for future climate (defined as the 2040-2070 normal period) under the RCP8.5 emission scenarios. Climate variables were chosen based on their known influence on local adaptation in plants, and include: mean annual temperature, summer maximum temperature, winter minimum temperature, annual temperature range, temperature seasonality (coefficient of variation in monthly average temperatures), mean annual precipitation, winter precipitation, summer precipitation, proportion of summer precipitation, precipitation...
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During a multi-year demographic study of Agassiz’s desert tortoise (Gopherus agassizii) at the Desert Tortoise Research Natural Area (Natural Area), in the western Mojave Desert, USA, we recorded evidence of evidence of mesocarnivores that commonly prey on desert tortoises on a 7.77 square-kilometer study area. The study area included land inside and outside the fenced boundary of the Natural Area. We recorded locations, condition and recency of sign, and type of sign present at burrows, dens, and den complexes used by desert kit foxes (Vulpes macrotis), coyotes (Canis latrans), American badgers (Taxidea taxus), and bobcats (Lynx rufus). We also recorded scat piles by species using them, amount, and relative ages...
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These data were compiled for a networked field-trial restoration experiment (RestoreNet) that spans the southwestern US, including 21 distributed field sites. The objective of our study was to understand the environmental factors and restoration practices (including seed mixes and soil manipulation) that increase plant establishment and survival to ultimate improve restoration outcomes in dryland environments. These data represent point-in-time plant density and height measurements at our field sites at the time of monitoring. These data were collected at 21 arid and semi-arid sites, located throughout Arizona, Utah, New Mexico, and California. These data were collected by USGS Restoration Assessment and Monitoring...
Categories: Data; Tags: Arizona, Botany, California, Chihuahuan Desert, Climatology, All tags...
What are current conditions for important park natural resources? What are the critical data and knowledge gaps? What are some of the factors that are influencing park resource conditions? Natural Resource Condition Assessments (NRCAs) evaluate and report on the above for a subset of important natural resources in national park units (hereafter, parks). Focal study resources and indicators are selected on a park-by-park basis, guided by use of structured resource assessment and reporting frameworks. Considerations include park resource setting and enabling legislation (what are this park's most important natural resources?) and presently available data and expertise (what can be evaluated at this time?). In addition...
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Natural landscapes in the Southwestern United States are changing. In recent decades, rising temperatures and drought have led to drier conditions, contributed to large-scale ecological impacts, and affected many plant and animal species across the region. The current and future trajectory of climate change underscores the need for managers and conservation professionals to understand the impacts of these patterns on natural resources. In this regional assessment of the Southwest Climate Change Initiative, we evaluate changes in annual average temperatures from 1951–2006 across major habitats and large watersheds and compare these changes to the number of species of conservation concern that are found within these...
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Passive seismic data collection was done northwest of the Air Force Research Laboratory (AFRL) at Edwards Air Force Base using the horizontal-to-vertical spectral ratio (HVSR) technique. HVSR surveys were done at 43 locations between May and September 2018 to refine the understanding of the bedrock-alluvial aquifer transition zone downgradient from the AFRL. Specifically, the data were collected to help determine the depth to bedrock. The HVSR method is a passive seismic technique that uses a three-component seismometer to measure the vertical and horizontal components of ambient seismic noise. Seismic noise in the range of ~0.1 to 1 Hertz (Hz) is caused by ocean waves, large regional storms, and tectonic sources....
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The U.S. Geological Survey collected groundwater samples from 48 grid wells and 11 understanding wells screened in aquifers used for domestic supply in San Bernardino County, California, in 2018. The sites were sampled for the Mojave Basin (MOBS) Shallow Aquifer Study Unit of the California State Water Resources Control Board Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project’s assessment of the quality of groundwater resources used for domestic and small system drinking water supplies. The MOBS study unit covered the Upper, Middle, and Lower Mojave River groundwater basins, El Mirage groundwater basin, and part of the Harper Valley groundwater basin [California Department of Water...
The recognition and characterization of aeolian dust in soil contribute to a better understanding of landscape and ecosystem dynamics of drylands. Results of this study show that recently deposited dust, sampled in isolated, mostly high-ground settings, is chemically and mineralogically similar on varied geologic substrates over a large area (15 000 km2) in the Mojave Desert. The silt-plus-clay fraction (fines) on these isolated surfaces is closely alike in magnetic-mineral composition, in contrast to greatly dissimilar magnetic compositions of rock surfaces of vastly different lithologies, on which the fines have accumulated. The fines, thus, are predominantly deposited dust. The amounts of potential nutrients...
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Studies were conducted in the central Mojave Desert to quantify how creosote bushes (Larrea tridentata) respond to physical damage during large-scale military training exercises. Creosote bush possesses a resilient growth form that recovers from repeated physical damage via resprouts arising from meristems in stem bark below severed or crushed canopy units. At high levels of disturbance by heavy vehicles, nearly all individuals showed measurable breakage, but without additional damage each plant can regain a full canopy within 5 years under arid field conditions. Resprouts exhibited more vigorous growth and doubled the biomass accumulation stimulated by high rainfall of 1998, an El Niño year, vs. a normal year....
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In this observational pilot study, we worked at the largest existing solar tower facility in the world (Ivanpah Solar Electric Generating System - ISEGS) to assess the efficacy of using radar, surveillance video, and insect trapping to monitor animals flying near the towers. During week-long site visits in May and September, we monitored the airspace surrounding towers and observed insects, occasional birds, and bats under a variety of environmental and operational conditions. This dataset enumerates invertebrates captured using both malaise and funnel traps placed on the ground in the immediate vicinity of solar towers in the locations shown in Figure 2 of the associated paper. The locational information below...
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In this observational pilot study, we worked at the largest existing solar tower facility in the world (Ivanpah Solar Electric Generating System - ISEGS) to assess the efficacy of using radar, surveillance video, and insect trapping to monitor animals flying near the towers. During week-long site visits in May and September, we monitored the airspace surrounding towers and observed insects, occasional birds, and bats under a variety of environmental and operational conditions. This dataset consists of raster portable network graphics (png) images of the planned position indicator (ppi) display from a Furuno FR2127 portable radar unit to a maximum range of 1.5 km. A new image is written with each rotation of the...
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Electrical resistivity tomography (ERT) surveys were done northwest of the Air Force Research Laboratory (AFRL) at Edwards Air Force Base. ERT surveys were done at four locations in May through June of 2018 to refine the understanding of the bedrock-alluvial aquifer transition zone downgradient from the AFRL. The ERT technique injects direct-current electricity with known voltage and current into the earth using a series of electrodes and measures the resulting resistivity. This technique is generally limited to investigations of aquifer properties less than 100 meters below land surface. Data from other geophysical techniques co-located with the ERT data, including time-domain electromagnetics and horizontal-to-vertical...
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The Air Force Research Laboratory (AFRL) is about 7 kilometers southwest of Boron, California, and covers 320 square kilometers of Edwards Air Force Base. The AFRL consists of 12 facilities for testing full-size rocket engines, engine components, and liquid and solid propellants. The historical release of contaminants from rocket test stands, evaporation ponds, burn pits, catch basins, and leaking waste-collection tanks has contaminated groundwater in the AFRL. Groundwater aquifers near the AFRL are mostly restricted to fractured granitic bedrock, but previous studies indicate that groundwater and associated contaminants have moved into alluvium to the north and northwest. The U.S. Geological Survey (USGS) and the...
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Time-domain electromagnetic (TEM) surveys were done northwest of the Air Force Research Laboratory (AFRL) at Edwards Air Force Base. TEM surveys were done at 33 locations between May and October 2018 to refine the understanding of the bedrock-alluvial aquifer transition zone downgradient from the AFRL. TEM surveys (also called transient electromagnetic surveys) provide 1D resistivity soundings of the subsurface, which can be related to lithology and hydrogeology. In the TEM method, electrical current is cycled through a transmitter loop (Tx) wire, which in turn produces a primary magnetic field. When the current is abruptly terminated, a secondary magnetic field is induced in the earth, and it moves downward and...
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LandScope America—a collaborative project of NatureServe and the National Geographic Society—is a new online resource for the land-protection community and the public. By bringing together maps, data, photos, and stories about America’s natural places and open spaces, our goal is to inform and inspire conservation of our lands and waters.
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The Southwest Regional Gap Analysis Project (SWReGAP) is an update of the Gap Analysis Program’s mapping and assessment of biodiversity for the five-state region encompassing Arizona, Colorado, Nevada, New Mexico, and Utah. It is a multi-institutional cooperative effort coordinated by the U.S. Geological Survey Gap Analysis Program. The primary objective of the update is to use a coordinated mapping approach to create detailed, seamless GIS maps of land cover, all native terrestrial vertebrate species, land stewardship, and management status, and to analyze this information to identify those biotic elements that are underrepresented on lands managed for their long term conservation or are “gaps.”
Precipitation varied substantially in the Mojave Desert through the 20th century in a manner broadly similar to the other warm North American deserts. Episodes of drought and prolonged dry conditions (1893–1904, ca. 1942–1975, and 1999-present) alternated with relatively wet periods (1905–ca. 1941 and ca. 1976–1998), probably because of global-scale climate fluctuations. These are the El Niño-Southern Oscillation that affects interannual climate and the Pacific Decadal Oscillation that evidently causes decadal-scale variability such as prolonged dry and wet episodes. Studies done in the late 20th century demonstrate that precipitation fluctuations affected populations of perennial vegetation, annuals, and small...


map background search result map search result map Resprout characteristics of creosote bush (Larrea tridentata) when subjected to repeated vehicle damage LandScope America Southwest Regional Gap Analysis Project Natural Resource Condition Assessments Managing Changing Landscapes in the Southwestern United States Invertebrate Data Radar Data Principal components of climate variation in the Desert Southwest for the future time period 2040-2070 (RCP 4.5) Climate Distance Mapper R Script Study Boundary and Grid Cells for the Mojave Basin Shallow Aquifer Study Unit Surface geophysics investigations at Edwards Air Force Research Laboratory, Antelope Valley, California, 2018 Ground-Based Time-Domain Electromagnetic Data Collected at Edwards Air Force Research Laboratory, Antelope Valley, California, 2018 Electrical Resistivity Tomography Data at Edwards Air Force Research Laboratory, Antelope Valley, California, 2018 Principal components of climate variation in the Desert Southwest for the future time period 2040-2070 (RCP 8.5) Horizontal-to-Vertical Seismic Ratio Passive-Seismic Data Collected at Edwards Air Force Research Laboratory, Antelope Valley, California, 2018 Evidence of Mammalian Carnivores at the Desert Tortoise Research Natural Area, Western Mojave Desert, USA, between 1989 and 2012. RestoreNet subplot data for 21 sites within major dryland ecoregions throughout the southwestern United States, 2018 - 2021 Invertebrate Data Radar Data Surface geophysics investigations at Edwards Air Force Research Laboratory, Antelope Valley, California, 2018 Ground-Based Time-Domain Electromagnetic Data Collected at Edwards Air Force Research Laboratory, Antelope Valley, California, 2018 Horizontal-to-Vertical Seismic Ratio Passive-Seismic Data Collected at Edwards Air Force Research Laboratory, Antelope Valley, California, 2018 Electrical Resistivity Tomography Data at Edwards Air Force Research Laboratory, Antelope Valley, California, 2018 Evidence of Mammalian Carnivores at the Desert Tortoise Research Natural Area, Western Mojave Desert, USA, between 1989 and 2012. Resprout characteristics of creosote bush (Larrea tridentata) when subjected to repeated vehicle damage Study Boundary and Grid Cells for the Mojave Basin Shallow Aquifer Study Unit RestoreNet subplot data for 21 sites within major dryland ecoregions throughout the southwestern United States, 2018 - 2021 Managing Changing Landscapes in the Southwestern United States Climate Distance Mapper R Script Principal components of climate variation in the Desert Southwest for the future time period 2040-2070 (RCP 4.5) Principal components of climate variation in the Desert Southwest for the future time period 2040-2070 (RCP 8.5) Southwest Regional Gap Analysis Project LandScope America Natural Resource Condition Assessments