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Novel catabolic pathways enabling rapid detoxification of s-triazine herbicides have been elucidated and detected at a growing number of locations. The genes responsible for s-triazine mineralization, i.e. atzABCDEF and trzNDF, occur in at least four bacterial phyla and are implicated in the development of enhanced degradation in agricultural soils from all continents except Antarctica. Enhanced degradation occurs in at least nine crops and six crop rotation systems that rely on s-triazine herbicides for weed control, and, with the exception of acidic soil conditions and s-triazine application frequency, adaptation of the microbial population is independent of soil physiochemical properties and cultural management...
A mathematically linked mercury transport, speciation, kinetic, and simple biotic uptake (BIOTRANSPEC) model has been developed. An extension of the metal transport and speciation (TRANSPEC) model, BIOTRANSPEC estimates the fate and biotic uptake of inorganic (Hg(II)), elemental (Hg(0)) and organic (MeHg) forms of mercury and their species in the dissolved, colloidal (e.g., dissolved organic matter [DOM]), and particulate phases of surface aquatic systems. A pseudo-steady state version of the model was used to describe mercury dynamics in Lahontan Reservoir (near Carson City, NV, USA), where internal loading of the historically deposited mercury is remobilized, thereby maintaining elevated water concentrations....
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This dataset represents the location and class density of potential annual grass risk within the Central Great Basin and Mojave Basin Ecoregion for the 2010 time period. This model represent a composite of multiple inductive (Maximum Entropy) models of varying annual grass cover using non-spectral landscape variables. Input Variables: elevation, aspect, distance to fire, geology, distance to hydric soils, distance to intermitant streams, landform, ombrotype, distance to perrenial streams, soil pH, density of primary roads, density of secondary/local roads, percent sandy soil, slope, thermotype. Classification of Model 0-No/Low Risk 1- < 5% Cover Risk 2- 5%-15% Cover Risk 3 - 15%-25% Cover Risk 4 - 25%-45% Cover...
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Complete terrestrial ecological systems dataset verion 2.8. Updates done for the 27 systems that are included in the final NatureServe CE dataset. Clipped to CBR & MBR. The dataset represents the work of multiple states and Federal agencies as part of the US Gap Analysis and LandFire programs. Multi-season satellite imagery (Landsat ETM+) from 1999-2001 were used in conjunction with digital elevation model (DEM) derived datasets (e.g. elevation, landform) to model natural and semi-natural vegetation. The minimum mapping unit for this dataset is approximately 1 acre. Landcover classes are drawn from NatureServe's Ecological System concept. Five-hundred and fourty-four land cover classes composed of 12 cultural and...
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Both tabular and spatial models were used to predict fire regime departure at the sub-watershed scale (i.e., HUC 10 units). Integrating the fire regime models with predicted changes in climate envelopes provides a clearer understanding of how these ecological systems are likely to respond to multiple stresses. The natural range of variability for each CE was initially derived from LANDFIRE Vegetation Dynamics Development Tool (VDDT) models. The VDDT allows for the development of probabilistic quantitative model of CEs consisting of multiple ecological states with both deterministic and probabilistic drivers. For any defined suite of drivers, the models predict the relative abundance of each state within a defined...
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Both tabular and spatial models were used to predict fire regime departure at the sub-watershed scale (i.e., HUC 10 units). Integrating the fire regime models with predicted changes in climate envelopes provides a clearer understanding of how these ecological systems are likely to respond to multiple stresses. The natural range of variability for each CE was initially derived from LANDFIRE Vegetation Dynamics Development Tool (VDDT) models. The VDDT allows for the development of probabilistic quantitative model of CEs consisting of multiple ecological states with both deterministic and probabilistic drivers. For any defined suite of drivers, the models predict the relative abundance of each state within a defined...
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The dataset represents the work of multiple states and Federal agencies as part of the US Gap Analysis and LandFire programs. Multi-season satellite imagery (Landsat ETM+) from 1999-2001 were used in conjunction with digital elevation model (DEM) derived datasets (e.g. elevation, landform) to model natural and semi-natural vegetation. The minimum mapping unit for this dataset is approximately 1 acre. Landcover classes are drawn from NatureServe's Ecological System concept. Five-hundred and fourty-four land cover classes composed of 12 cultural and 532 Natural/Semi-natural types are described. Land cover classes were mapped with a variety of techniques including decision tree classifiers, terrian modeling, inductive...
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This dataset was derived from 'NatureServe L48 ESLF V2.7'. See process steps for additional information. The dataset represents the work of multiple states and Federal agencies as part of the US Gap Analysis and LandFire programs. Multi-season satellite imagery (Landsat ETM+) from 1999-2001 were used in conjunction with digital elevation model (DEM) derived datasets (e.g. elevation, landform) to model natural and semi-natural vegetation. The minimum mapping unit for this dataset is approximately 1 acre. Landcover classes are drawn from NatureServe's Ecological System concept. Five-hundred and fourty-four land cover classes composed of 12 cultural and 532 Natural/Semi-natural types are described. Land cover classes...
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This dataset represents the location and class density of potential annual grass risk within the Central Great Basin and Mojave Basin Ecoregion for the 2010 time period. This model represent a composite of multiple inductive (Maximum Entropy) models of varying annual grass cover using non-spectral landscape variables. Input Variables: elevation, aspect, distance to fire, geology, distance to hydric soils, distance to intermitant streams, landform, ombrotype, distance to perrenial streams, soil pH, density of primary roads, density of secondary/local roads, percent sandy soil, slope, thermotype. Classification of Model 0-No/Low Risk 1- < 5% Cover Risk 2- 5%-15% Cover Risk 3 - 15%-25% Cover Risk 4 - 25%-45% Cover...
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Both tabular and spatial models were used to predict fire regime departure at the sub-watershed scale (i.e., HUC 10 units). Integrating the fire regime models with predicted changes in climate envelopes provides a clearer understanding of how these ecological systems are likely to respond to multiple stresses. The natural range of variability for each CE was initially derived from LANDFIRE Vegetation Dynamics Development Tool (VDDT) models. The VDDT allows for the development of probabilistic quantitative model of CEs consisting of multiple ecological states with both deterministic and probabilistic drivers. For any defined suite of drivers, the models predict the relative abundance of each state within a defined...
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Both tabular and spatial models were used to predict fire regime departure at the sub-watershed scale (i.e., HUC 10 units). Integrating the fire regime models with predicted changes in climate envelopes provides a clearer understanding of how these ecological systems are likely to respond to multiple stresses. The natural range of variability for each CE was initially derived from LANDFIRE Vegetation Dynamics Development Tool (VDDT) models. The VDDT allows for the development of probabilistic quantitative model of CEs consisting of multiple ecological states with both deterministic and probabilistic drivers. For any defined suite of drivers, the models predict the relative abundance of each state within a defined...
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The dataset represents the work of multiple states and Federal agencies as part of the US Gap Analysis and LandFire programs. Multi-season satellite imagery (Landsat ETM+) from 1999-2001 were used in conjunction with digital elevation model (DEM) derived datasets (e.g. elevation, landform) to model natural and semi-natural vegetation. The minimum mapping unit for this dataset is approximately 1 acre. Landcover classes are drawn from NatureServe's Ecological System concept. Five-hundred and fourty-four land cover classes composed of 12 cultural and 532 Natural/Semi-natural types are described. Land cover classes were mapped with a variety of techniques including decision tree classifiers, terrian modeling, inductive...
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This report is intended to provide guidance to local emergency managers in tsunami hazard assessment. Tsunami waves are a real threat for many Alaskan coastal locations, and community preparedness plays an important role in saving lives and property in a case of such a disaster. In this work we used a numerical modeling method to study tsunami waves generated by earthquake sources. We considered several hypothetical tsunami scenarios with a potential to generate tsunami waves that can affect communities in the Kodiak vicinity. Our results confirm that among the earthquake-generated tsunamis we modeled, the 1964 event can be considered a worst-case scenario for future planning. Although our tsunami models included...
Abstract (from http://journal.frontiersin.org/article/10.3389/fpls.2014.00785/abstract): Fire is a key ecological process affecting vegetation dynamics and land cover. The characteristic frequency, size, and intensity of fire are driven by interactions between top-down climate-driven and bottom-up fuel-related processes. Disentangling climatic from non-climatic drivers of past fire regimes is a grand challenge in Earth systems science, and a topic where both paleoecology and ecological modeling have made substantial contributions. In this manuscript, we (1) review the use of sedimentary charcoal as a fire proxy and the methods used in charcoal-based fire history reconstructions; (2) identify existing techniques...
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Digital flood-inundation maps for an 18.6-mile (mi) reach of the Clear Fork Mohican River that extends approximately from 100 feet upstream from Gass Road near Lexington, Ohio to 700 feet downstream from Benedict Road in Butler , Ohio, were created by the U.S. Geological Survey (USGS) in cooperation with the Muskingum Watershed Conservancy District as part of a Federal Emergency Management Agency (FEMA) Flood Insurance Study (FIS). The flood-inundation maps show estimates of the areal extent corresponding to the 1% and 0.2% annual-exceedance probability floods. Flood profiles were computed for the stream reach by means of the one-dimensional step-backwater model HEC–RAS. The model was calibrated by using the current...
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The travel time map was generated using the Pedestrian Evacuation Analyst model (version 1.0.1 for ArcGIS 10.5) from the USGS (https://geography.wr.usgs.gov/science/vulnerability/tools.html). The travel time analysis uses ESRI's Path Distance tool to find the shortest distance across a cost surface from any point in the hazard zone to a safe zone. This cost analysis considers the direction of movement and assigns a higher cost to steeper slopes, based on a table contained within the model. The analysis also adds in the energy costs of crossing different types of land cover, assuming that less energy is expended walking along a road than walking across a sandy beach. To produce the time map, the evacuation surface...
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The travel time map was generated using the Pedestrian Evacuation Analyst model (version 1.0.1 for ArcGIS 10.5) from the USGS (https://geography.wr.usgs.gov/science/vulnerability/tools.html). The travel time analysis uses ESRI's Path Distance tool to find the shortest distance across a cost surface from any point in the hazard zone to a safe zone. This cost analysis considers the direction of movement and assigns a higher cost to steeper slopes, based on a table contained within the model. The analysis also adds in the energy costs of crossing different types of land cover, assuming that less energy is expended walking along a road than walking across a sandy beach. To produce the time map, the evacuation surface...


map background search result map search result map Tsunami hazard maps of the Kodiak area, Alaska Tsunami evacuation time map for American Samoa predicted maximum tsunami (PMT) inundation zone and slow walk speed Tsunami evacuation time map for American Samoa predicted maximum tsunami (PMT) inundation zone and fast walk speed Input and output shapefiles used in the hydraulic modeling for the Clear Fork Mohican River and Cedar Fork in Richland County, Ohio BLM REA MBR 2010 Risk Model of Invasive Annual Grasses - CBR and MBR BLM REA MBR 2010 NatureServe Terrestrial Ecological Systems IMBMixedSaltDesertScrub BLM REA MBR 2010 NatureServe Terrestrial Ecological Systems, version 2.8 BLM REA MBR 2010 GEODB.SDE.CEI NATURESERVE L48 ESLF V2 7 BLM REA CBR 2010 Ecological System Fire Regime Departure - 2060 Inter-Mountain Basins Subalpine Limber-Bristlecone Pine Woodland BLM REA CBR 2010 Ecological System Fire Regime Departure - Colorado Plateau Mixed Low Sagebrush Shrubland BLM REA CBR 2010 Ecological System Fire Regime Departure - 2060 Great Basin Xeric Mixed Sagebrush Shrubland BLM REA CBR 2010 Ecological System Fire Regime Departure - 2025 Inter-Mountain Basins Subalpine Limber-Bristlecone Pine Woodland BLM REA CBR 2010 NatureServe GBPinyonJuniperWoodlndTerrestrial Ecological Systems BLM REA CBR 2010 Risk Model of Invasive Annual Grasses - CBR and MBR Input and output shapefiles used in the hydraulic modeling for the Clear Fork Mohican River and Cedar Fork in Richland County, Ohio Tsunami hazard maps of the Kodiak area, Alaska BLM REA CBR 2010 Ecological System Fire Regime Departure - Colorado Plateau Mixed Low Sagebrush Shrubland BLM REA MBR 2010 NatureServe Terrestrial Ecological Systems IMBMixedSaltDesertScrub BLM REA MBR 2010 GEODB.SDE.CEI NATURESERVE L48 ESLF V2 7 BLM REA CBR 2010 Ecological System Fire Regime Departure - 2060 Inter-Mountain Basins Subalpine Limber-Bristlecone Pine Woodland BLM REA CBR 2010 Ecological System Fire Regime Departure - 2025 Inter-Mountain Basins Subalpine Limber-Bristlecone Pine Woodland BLM REA CBR 2010 NatureServe GBPinyonJuniperWoodlndTerrestrial Ecological Systems BLM REA CBR 2010 Ecological System Fire Regime Departure - 2060 Great Basin Xeric Mixed Sagebrush Shrubland BLM REA MBR 2010 NatureServe Terrestrial Ecological Systems, version 2.8 BLM REA MBR 2010 Risk Model of Invasive Annual Grasses - CBR and MBR BLM REA CBR 2010 Risk Model of Invasive Annual Grasses - CBR and MBR