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This dataset represents the soil texture from SSURGO and STATSGO soil descriptions for soil map units in the state of western Oregon that lie within the North Pacific Landscape Conservation Cooperative. Soil texture is the mineral particle size distribution of soil particles within a soil horizon. This dataset also documents rock fragments and organic matter that may contribute to water infiltration, storage and relocation within the surface horizons of the soil profile. For reference, see NRCS soil texture triangle: http://soils.usda.gov/technical/aids/investigations/texture/
We investigated the bioavailability via diet of spiked benzo[a]pyrene (BaP) and 2,2',5,5'-tetrachlorobiphenyl (PCB-52) from different carbonaceous (non-carbonate, carbon containing) particle types to clams (Macoma balthica) collected from San Francisco Bay. Our results reveal significant differences in absorption efficiency between compounds and among carbonaceous particle types. Absorption efficiency for PCB-52 was always greater than that for BaP bound to a given particle type. Among particles, absorption efficiency was highest from wood and diatoms and lowest from activated carbon. Large differences in absorption efficiency could not be simply explained by comparatively small differences in the particles' total...
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This dataset represents the soil texture from SSURGO and STATSGO soil descriptions for soil map units in the state of northern California that lie within the North Pacific Landscape Conservation Cooperative. Soil texture is the mineral particle size distribution of soil particles within a soil horizon. This dataset also documents rock fragments and organic matter that may contribute to water infiltration, storage and relocation within the surface horizons of the soil profile. For reference, see NRCS soil texture triangle: http://soils.usda.gov/technical/aids/investigations/texture/
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This dataset represents the soil texture from SSURGO and STATSGO soil descriptions for soil map units in the state of western Washington that lie within the North Pacific Landscape Conservation Cooperative. Soil texture is the mineral particle size distribution of soil particles within a soil horizon. This dataset also documents rock fragments and organic matter that may contribute to water infiltration, storage and relocation within the surface horizons of the soil profile. For reference, see NRCS soil texture triangle: http://soils.usda.gov/technical/aids/investigations/texture/
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This dataset represents the soil texture from SSURGO and STATSGO soil descriptions for soil map units in the state of western Oregon that lie within the North Pacific Landscape Conservation Cooperative. Soil texture is the mineral particle size distribution of soil particles within a soil horizon. This dataset also documents rock fragments and organic matter that may contribute to water infiltration, storage and relocation within the surface horizons of the soil profile. For reference, see NRCS soil texture triangle: http://soils.usda.gov/technical/aids/investigations/texture/
This data release consists of tables with the thickness and particle-size characteristics of overbank sediment deposited in May 1978 along the valley of Powder River in southeastern Montana. About 900 sediment samples were collected at regularly-spaced distances from 20 valley transects along a 90-kilometer reach of Powder River between Moorhead and Broadus, Montana. The decrease in sediment thickness and particle size with distance from the main channel showed weak trends, which were caused by the variability introduced by vegetation sediment traps and subsidiary channels.
To test the effect of geochemical heterogeneity on microorganism transport in saturated porous media, we measured the removal of two microorganisms, the bacteriophage PRD1 and oocysts of the protozoan parasite Cryptosporidium parvum, in flow-through columns of quartz sand coated by different amounts of a ferric oxyhydroxide. The experiments were conducted over ranges of ferric oxyhydroxide coating fraction of lambda = 0-0.12 for PRD1 and from lambda = 0-0.32 for the oocysts at pH 5.6-5.8 and 10(-4) M ionic strength. To determine the effect of pH on the transport of the oocysts, experiments were also conducted over a pH range of 5.7-10.0 at a coating fraction of lambda = 0.04. Collision (attachment) efficiencies...
This work characterizes the efficacy of activated carbon amendment in reducing polychlorinated biphenyl (PCB) bioavailability to clams (Macoma balthica) from field-contaminated sediment (Hunters Point Naval Shipyard, San Francisco Bay, CA, USA). Test methods were developed for the use of clams to investigate the effects of sediment amendment on biological uptake. Sediment was mixed with activated carbon for one month. Bioaccumulation tests (28 d) were employed to assess the relationships between carbon dose and carbon particle size on observed reductions in clam biological uptake of PCBs. Extraction and cleanup protocols were developed for the clam tissue. Efficacy of activated carbon treatment was found to increase...
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The dataset documents results from particle size analysis conducted on a suite of sediment samples from the VA-Clarke-03 core, Cherry Hill quadrangle, Dinwiddie county, Virginia [36.931926, -77.566802]. The 44-foot-long core was collected on 05/16/2023 using the North Carolina Geological Survey Geoprobe. The core was collected from sands and gravels of the uppermost coastal plain that host the Old Hickory heavy mineral deposit. Because host sediments are non-fossiliferous, there is little consensus as to their age, stratigraphic position, or nomenclature. Current mapping assigns host sands and gravels to two units in the upper part of the Pliocene to Pleistocene Chesapeake Group. In the lab, the core was analyzed...
Atmospheric particulate matter (PM) is a heterogeneous material. Though regulated as un-speciated mass, it exerts most effects on vegetation and ecosystems by virtue of the mass loading of its chemical constituents. As this varies temporally and spatially, prediction of regional impacts remains difficult. Deposition of PM to vegetated surfaces depends on the size distribution of the particles and, to a lesser extent, on the chemistry. However, chemical loading of an ecosystem may be determined by the size distribution as different constituents dominate different size fractions. Coating with dust may cause abrasion and radiative heating, and may reduce the photosynthetically active photon flux reaching the photosynthetic...
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The United States Geological Survey Virginia and West Virginia Water Science Center (USGS VA-WV-WSC) and Fairfax County assembled this data release in support of ongoing USGS VA-WV-WSC monitoring and evaluations of stream conditions overtime of two previously restored, urban-suburban streams in Reston, Virginia – Snakeden Branch and The Glade. The aquatic benthic macroinvertebrate, fish, and habitat sampling and surveying were conducted on the same eight, 100-meter stream reaches (four reaches in Snakeden Branch and four reaches in The Glade) by the USGS VA-WV-WSC. Aquatic benthic macroinvertebrate sampling and physical habitat surveys were conducted in both Spring and Fall of 2021 and a fish survey was conducted...
Traditional models of soil organic matter decomposition predict that soil carbon pools with high chemical stability and large physical structure are more resistant against degradation than chemically labile and fine-grained material. We investigated whether soil fauna, by its direct and indirect effects on carbon turnover, would reinforce or counteract this general trend. The effects of four major faunal groups on carbon pools of differing recalcitrance were studied in an extensive microcosm experiment. Ninty-six microcosms were inoculated with nematodes, enchytraeids, collembola, and lumbricids in three densities, including combinations of groups. Bare agricultural soil and soil covered with maize litter were used...


    map background search result map search result map Soil texture for the North Pacific Landscape Conservation Cooperative- western Oregon, USA Soil texture for the North Pacific Landscape Conservation Cooperative- northern California, USA Soil texture for the North Pacific Landscape Conservation Cooperative- western Washington, USA Soil texture for the North Pacific Landscape Conservation Cooperative- western Oregon, USA Thickness and characteristics of overbank sediment deposited during an extreme flood in May 1978 along Powder River, Montana, USA Benthic macroinvertebrate, fish, and physical habitat data for selected streams in Reston, VA Particle size analysis results from the VA-Clarke-03 core, Cherry Hill quadrangle, Dinwiddie County, Virginia Particle size analysis results from the VA-Clarke-03 core, Cherry Hill quadrangle, Dinwiddie County, Virginia Benthic macroinvertebrate, fish, and physical habitat data for selected streams in Reston, VA Thickness and characteristics of overbank sediment deposited during an extreme flood in May 1978 along Powder River, Montana, USA Soil texture for the North Pacific Landscape Conservation Cooperative- northern California, USA Soil texture for the North Pacific Landscape Conservation Cooperative- western Washington, USA Soil texture for the North Pacific Landscape Conservation Cooperative- western Oregon, USA Soil texture for the North Pacific Landscape Conservation Cooperative- western Oregon, USA