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The Microscopic Imager (MI) on the Mars Exploration Rover Opportunity has returned images of Mars with higher resolution than any previous camera system, allowing detailed petrographic and sedimentological studies of the rocks and soils at the Meridiani Planum landing site. Designed to simulate a geologist's hand lens, the MI is mounted on Opportunity's instrument arm and can resolve objects 0.1 mm across or larger. This paper provides an overview of MI operations, data calibration, and analysis of MI data returned during the first 900 sols (Mars days) of the Opportunity landed mission. Analyses of Opportunity MI data have helped to resolve major questions about the origin of observed textures and features. These...
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This map shows the distribution of anomalous tungsten in the two sample fractions, magnetic (M-1) and nonmagnetic (NM-1) gold in the nonmagnetic (NM-1) fraction; these are plotted on a base which includes sample localities, topography, and generalized geology modified from Hedlund (1975a, b). It is part of a series of maps for several metals that accompany this folio. Distributions of the tungsten and gold values are shown on the accompanying histograms.
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A pore network model with cubic chambers and rectangular tubes was used to estimate the nonaqueous phase liquid (NAPL) dissolution rate coefficient, Kdissai, and NAPL/water total specific interfacial area, ai. Kdissai was computed as a function of modified Peclet number(Pe′) for various NAPL saturations (SN) and ai during drainage and imbibition and during dissolution without displacement. The largest contributor to ai was the interfacial area in the water-filled corners of chambers and tubes containing NAPL. When Kdissai was divided by ai, the resulting curves of dissolution coefficient, Kdiss versus Pe′ suggested that an approximate value of Kdiss could be obtained as a weak function of hysteresis or SN. Spatially...
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Unlike conventional flood control systems that frequently isolate rivers from ecologically-essential floodplain habitat, California's Yolo Bypass has been engineered to allow Sacramento Valley floodwaters to inundate a broad floodplain. From a flood control standpoint, the 24,000 ha leveed floodplain has been exceptionally successful based on its ability to convey up to 80% of the flow of the Sacramento River basin during high water events. Agricultural lands and seasonal and permanent wetlands within the bypass provide key habitat for waterfowl migrating through the Pacific Flyway. Our field studies demonstrate that the bypass seasonally supports 42 fish species, 15 of which are native. The floodplain appears to...
Categories: Publication; Types: Citation; Tags: Fisheries
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This EnviroAtlas web service supports research and online mapping activities related to EnviroAtlas (https://www.epa.gov/enviroatlas). The Clean and Plentiful Water category in this web service includes layers illustrating the ecosystems and natural resources that filter and regulate water, the need or demand for clean and plentiful water, the impacts associated with water quality, and factors that place stress on water quality and supply. EnviroAtlas allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the conterminous United States. Additional descriptive information about each attribute in this web service is located within each web...
Types: Citation; Tags: 12-digit HUCs, Agriculture, Air, Alabama, Alaska, All tags...
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These are the original hexagons created for the 2013 Crucial Habitat Assessment Tool (CHAT) for Colorado, but the attributes have been updated with the 2015 revision to reflect the revised (2015 SWAP Revision) list of Tier 1 Species of Greatest Conservation Need (SGCN), and to incorporate updated occurrence data and improved distribution data for some species. CNHP developed species distribution models for 17 Tier 1 SGCN. Both documented and modeled distribution data for Tier 1 animal and plant SGCN have been combined at the resolution of 640 acre hexagons across the state. Each hexagon is then placed into one of six CHAT priority categories based on rules developed by the Western Governor's Association CHAT member...
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This EnviroAtlas web service supports research and online mapping activities related to EnviroAtlas (https://www.epa.gov/enviroatlas). The Food, Fuel, and Materials category in this web service includes layers illustrating the ecosystems and natural resources that provide or support the production of food, fuel, or other materials, the need or demand for these items, the impacts associated with their presence and accessibility, and factors that place stress on the natural environment's capability to provide these benefits. EnviroAtlas allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the conterminous United States. Additional descriptive...
Types: Citation; Tags: 12-digit HUCs, Agriculture, Air, Alabama, Alaska, All tags...
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Ecological Focus Areas (EFA), geographically explicit areas in which to address conservation issues, represent landscapes where conservation actions can be applied for maximum benefit to all Kansas wildlife. Each EFA includes a suite of SGCN and priority habitats and a unique set of conservation actions designed to address the specific resource concerns facing these species and habitats. Each EFA also includes one or more protected areas that can serve as demonstration sites for conservation actions.
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This layer represents the number of Tier 1 fish species known to occur in each HUC10 watershed in the state, according to data available in CPW’s fish database as of December 2014. There are 25 fish species on the Tier 1 SGCN list; a maximum of eight different species occur in the same watershed. This map is an indicator of species richness only; it does not consider relative habitat quality, or population metrics such as density or abundance, across watersheds.
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This dataset represents the Terrestrial Conservation Opportunity Areas identified by the 2015 update to Missouri's State Wildlife Action Plan.
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The Conservation Opportunity Areas (COAs) for Tennessee capture populations of GCN species and high quality habitats, and as appropriate, define the geographically relevant framework for achieving conservation outcomes. The COAs currently designed for Tennessee are large geographies, with the expectation that further prioritization and goal setting for specific habitat outcomes can be achieved within them through collaborations with partners on shared objectives. While designing the COAs for Tennessee, the planning team considered three major attributes: GCN habitat priority, the problems affecting the habitats, and the on-the-ground opportunities to implement conservation actions.
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Hydrologists often attempt to estimate formation properties from aquifer tests for which only the hydraulic responses in a pumped well are available. Borehole storage, turbulent head losses, and borehole skin, however, can mask the hydraulic behavior of the formation inferred from the water level in the pumped well. Also, in highly permeable formations or in formations at significant depth below land surface, where there is a long column of water in the well casing, oscillatory water levels may arise during the onset of pumping to further mask formation responses in the pumped well. Usually borehole phenomena are confined to the early stages of pumping or recovery, and late-time hydraulic data can be used to estimate...
Categories: Publication; Types: Citation; Tags: Journal of Hydrology
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More than 70 individual VOCs were identified in the leachate plume of a closed municipal landfill. Concentrations were low when compared with data published for other landfills, and total VOCs accounted for less than 0.1% of the total dissolved organic carbon. The VOC concentrations in the core of the anoxic leachate plume are variable, but in all cases they were found to be near or below detection limits within 200 m of the landfall. In contrast to the VOCs, the distributions of chloride ion, a conservative tracer, and nonvolatile dissolved organic carbon, indicate little dilution over the same distance. Thus, natural attentuation processes are effectively limiting migration of the VOC plume. The distribution of...
Categories: Publication; Types: Citation; Tags: Groundwater
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The crystallization of calcium carbonate minerals plays an integral role in the water chemistry of terrestrial ecosystems. Humic substances, which are ubiquitous in natural waters, have been shown to reduce or inhibit calcite crystal growth in experiments. The purpose of this study is to quantify and understand the kinetic effects of hydrophobic organic acids isolated from the Florida Everglades and a fulvic acid from Lake Fryxell, Antarctica, on the crystal growth of calcite (CaCO3). Highly reproducible calcite growth experiments were performed in a sealed reactor at constant pH, temperature, supersaturation (Ω = 4.5), PCO2(10−3.5atm), and ionic strength (0.1 M) with various concentrations of organic acids. Higher...
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Investigation of water resources by the United States Geological Survey has consisted in large part of measurements of the volume of flow of streams and studies of the conditions affecting that flow, but it has comprised also investigation of such closely allied subjects as irrigation, water storage, water powers, underground waters, and quality of waters. Most of the results of these investigations have been published in the series of water-supply papers, but some have appeared in the monographs, bulletins, professional papers, and annual reports.
Categories: Publication; Types: Citation; Tags: Water Supply Paper
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The Sierra Nevada region is critical to the environment and economy of California. Its places and peoples provideessential natural resources including fresh water, clean power, working lands, and famous wilderness. The regionencompasses tremendous geographical, climatological, and ecological diversity that spans majestic mountains todeep desert basins. The climate consists of cool, wet winters and warm, dry summers with large differences due tolatitude (e.g., the southern Sierra is snowier than northern Sierra) and topography (e.g., the Westside is wetter thanthe Eastside). Variability is another notable feature of the climate with the region experiencing some of the largestyear-to-year climatic fluctuations in...
Categories: Publication; Types: Citation


map background search result map search result map UMRGLR JV - Wetland Breeding Bird Habitat Priorities EnviroAtlas - Clean and Plentiful Water Metrics for the Conterminous United States EnviroAtlas - Food, Fuel, and Materials Metrics for Conterminous United States Colorado - Priority Watersheds for Tier 1 Aquatic SGCN Colorado - Priority Habitat for Tier 1 Terrestrial Animal and Plant SGCN Kansas - Terrestrial Ecological Focus Areas Missouri - Terrestrial Conservation Opportunity Areas Tennessee Conservation Opportunity Areas Tennessee Conservation Opportunity Areas Kansas - Terrestrial Ecological Focus Areas Missouri - Terrestrial Conservation Opportunity Areas Colorado - Priority Habitat for Tier 1 Terrestrial Animal and Plant SGCN Colorado - Priority Watersheds for Tier 1 Aquatic SGCN UMRGLR JV - Wetland Breeding Bird Habitat Priorities EnviroAtlas - Clean and Plentiful Water Metrics for the Conterminous United States EnviroAtlas - Food, Fuel, and Materials Metrics for Conterminous United States