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The RCMAP (Rangeland Condition Monitoring Assessment and Projection) dataset quantifies the percent cover of rangeland components across the western U.S. using Landsat imagery from 1985-2020. The RCMAP product suite consists of eight fractional components: annual herbaceous, bare ground, herbaceous, litter, non-sagebrush shrub, perennial herbaceous, sagebrush, shrub and rule-based error maps including the temporal trends of each component. Several enhancements were made to the RCMAP process relative to prior generations. We used an updated version of the 2016 base training data, with a more aggressive forest mask and reduced shrub and sagebrush cover bias in pinyon-juniper woodlands. We pooled training data in areas...
The RCMAP (Rangeland Condition Monitoring Assessment and Projection) dataset quantifies the percent cover of rangeland components across western North America using Landsat imagery from 1985-2023. The RCMAP product suite consists of ten fractional components: annual herbaceous, bare ground, herbaceous, litter, non-sagebrush shrub, perennial herbaceous, sagebrush, shrub, tree, and shrub height in addition to the temporal trends of each component. Several enhancements were made to the RCMAP process relative to prior generations. First, high-resolution training was revised using an improved neural-net classifier and modelling approach. These data serve as foundation to the RCMAP approach. The training database was...
Climate change over the past century has altered vegetation community composition and species distributions across rangelands in the western United States. The scale and magnitude of climatic influences are largely unknown. While a number of studies have projected the impacts of climate change using several modeling approaches, none has evaluated impacts to fractional component cover at a 30-m resolution across rangelands of the Western U.S. We used fractional component cover data for rangeland functional groups and weather data from the 1985 to 2021 reference period in conjunction with soils and topography data to develop empirical models describing the spatio-temporal variation in component cover. To investigate...
Sagebrush ecosystems in North America have experienced extensive degradation since European settlement, and continue to further degrade from exotic invasive plants, greater fire frequency, intensive grazing practices, increased oil and gas development, climate change, and other factors. Remote sensing is often identified as a key information source to facilitate broad-area ecosystem-wide characterization, monitoring and analysis, however, approaches that characterize sagebrush with sufficient and accurate local detail across large areas to support ecosystem research and analysis are unavailable. We have developed a new remote sensing sagebrush ecosystem characterization approach for the state of Wyoming, U.S.A....
Annual Herbaceous Percent - Provisional Remote Sensing Shrub/Grass NLCD Products for the Great Basin
Accurate and consistent estimates of shrubland ecosystem components are crucial to a better understanding of ecosystems condition in arid and semiarid lands. We developed an innovative approach by integrating multiple information to quantify shrubland components as continuous field products within the National Land Cover Database (NLCD). The approach consists of five major parts: field sample collection, high-resolution mapping of shrubland components using WorldView-2 imagery and regression tree models, Landsat 8 radiometric balancing and phenological mosaicking, coarse resolution estimate of shrubland components across a large geographic extent using Landsat 8 phenological mosaics and regression tree models, and...
Accurate and consistent estimates of shrubland ecosystem components are crucial to a better understanding of ecosystems condition in arid and semiarid lands. We developed an innovative approach by integrating multiple information to quantify shrubland components as continuous field products within the National Land Cover Database (NLCD). The approach consists of five major parts: field sample collection, high-resolution mapping of shrubland components using WorldView-2 imagery and regression tree models, Landsat 8 radiometric balancing and phenological mosaicking, coarse resolution estimate of shrubland components across a large geographic extent using Landsat 8 phenological mosaics and regression tree models, and...
The RCMAP (Rangeland Condition Monitoring Assessment and Projection) dataset quantifies the percent cover of rangeland components across western North America using Landsat imagery from 1985-2023. The RCMAP product suite consists of ten fractional components: annual herbaceous, bare ground, herbaceous, litter, non-sagebrush shrub, perennial herbaceous, sagebrush, shrub, tree, and shrub height in addition to the temporal trends of each component. Several enhancements were made to the RCMAP process relative to prior generations. First, high-resolution training was revised using an improved neural-net classifier and modelling approach. These data serve as foundation to the RCMAP approach. The training database was...
The RCMAP (Rangeland Condition Monitoring Assessment and Projection) dataset quantifies the percent cover of rangeland components across western North America using Landsat imagery from 1985-2023. The RCMAP product suite consists of ten fractional components: annual herbaceous, bare ground, herbaceous, litter, non-sagebrush shrub, perennial herbaceous, sagebrush, shrub, tree, and shrub height in addition to the temporal trends of each component. Several enhancements were made to the RCMAP process relative to prior generations. First, high-resolution training was revised using an improved neural-net classifier and modelling approach. These data serve as foundation to the RCMAP approach. The training database was...
The need to monitor change in sagebrush steppe is urgent due to the increasing impacts of climate change, shifting fire regimes, and management practices on ecosystem health. Remote sensing provides a cost-effective and reliable method for monitoring change through time and attributing changes to drivers. We report an automated method of mapping rangeland fractional component cover over a large portion of the Northern Great Basin, USA, from 1986 to 2016 using a dense Landsat imagery time series. 2012 was excluded from the time-series due to a lack of quality imagery. Our method improved upon the traditional change vector method by considering the legacy of change at each pixel. We evaluate cover trends stratified...
Sagebrush ecosystems in North America have experienced extensive degradation since European settlement, and continue to further degrade from exotic invasive plants, greater fire frequency, intensive grazing practices, increased oil and gas development, climate change, and other factors. Remote sensing is often identified as a key information source to facilitate broad-area ecosystem-wide characterization, monitoring and analysis, however, approaches that characterize sagebrush with sufficient and accurate local detail across large areas to support ecosystem research and analysis are unavailable. We have developed a new remote sensing sagebrush ecosystem characterization approach for the state of Wyoming, U.S.A....
Sagebrush ecosystems in North America have experienced extensive degradation since European settlement, and continue to further degrade from exotic invasive plants, greater fire frequency, intensive grazing practices, increased oil and gas development, climate change, and other factors. Remote sensing is often identified as a key information source to facilitate broad-area ecosystem-wide characterization, monitoring and analysis, however, approaches that characterize sagebrush with sufficient and accurate local detail across large areas to support ecosystem research and analysis are unavailable. We have developed a new remote sensing sagebrush ecosystem characterization approach for the state of Wyoming, U.S.A....
The introduction of nonnative plant species may decrease ecosystem stability by altering the availability of nitrogen (N) for plant growth. Invasive species can impact N availability by changing litter quantity and quality, rates of N2-fixation, or rates of N loss. We quantified the effects of invasion by the annual grass Bromus tectorum on N cycling in an arid grassland on the Colorado Plateau (USA). The invasion occurred in 1994 in two community types in an undisturbed grassland. This natural experiment allowed us to measure the immediate responses following invasion without the confounding effects of previous disturbance. Litter biomass and the C:N and lignin:N ratios were measured to determine the effects on...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Bromus tectorum,
Canyonlands National Park,
Ecological Applications,
N mineralization,
Utah,
Sagebrush ecosystems in North America have experienced extensive degradation since European settlement, and continue to further degrade from exotic invasive plants, greater fire frequency, intensive grazing practices, increased oil and gas development, climate change, and other factors. Remote sensing is often identified as a key information source to facilitate broad-area ecosystem-wide characterization, monitoring and analysis, however, approaches that characterize sagebrush with sufficient and accurate local detail across large areas to support ecosystem research and analysis are unavailable. ?We have developed a new remote sensing sagebrush ecosystem characterization approach for the state of Wyoming, U.S.A....
The introduction of nonnative plant species may decrease ecosystem stability by altering the availability of nitrogen (N) for plant growth. Invasive species can impact N availability by changing litter quantity and quality, rates of N2-fixation, or rates of N loss. We quantified the effects of invasion by the annual grass Bromus tectorum on N cycling in an arid grassland on the Colorado Plateau (USA). The invasion occurred in 1994 in two community types in an undisturbed grassland. This natural experiment allowed us to measure the immediate responses following invasion without the confounding effects of previous disturbance. Litter biomass and the C:N and lignin:N ratios were measured to determine the effects on...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Bromus tectorum,
Canyonlands National Park,
Ecological Applications,
N mineralization,
Utah,
The RCMAP (Rangeland Condition Monitoring Assessment and Projection) dataset quantifies the percent cover of rangeland components across the western U.S. using Landsat imagery from 1985-2020. The RCMAP product suite consists of eight fractional components: annual herbaceous, bare ground, herbaceous, litter, non-sagebrush shrub, perennial herbaceous, sagebrush, shrub and rule-based error maps including the temporal trends of each component. Several enhancements were made to the RCMAP process relative to prior generations. We used an updated version of the 2016 base training data, with a more aggressive forest mask and reduced shrub and sagebrush cover bias in pinyon-juniper woodlands. We pooled training data in areas...
The RCMAP (Rangeland Condition Monitoring Assessment and Projection) dataset quantifies the percent cover of rangeland components across the western U.S. using Landsat imagery from 1985-2020. The RCMAP product suite consists of eight fractional components: annual herbaceous, bare ground, herbaceous, litter, non-sagebrush shrub, perennial herbaceous, sagebrush, shrub and rule-based error maps including the temporal trends of each component. Several enhancements were made to the RCMAP process relative to prior generations. We used an updated version of the 2016 base training data, with a more aggressive forest mask and reduced shrub and sagebrush cover bias in pinyon-juniper woodlands. We pooled training data in areas...
The RCMAP (Rangeland Condition Monitoring Assessment and Projection) dataset quantifies the percent cover of rangeland components across the western U.S. using Landsat imagery from 1985-2021. The RCMAP product suite consists of nine fractional components: annual herbaceous, bare ground, herbaceous, litter, non-sagebrush shrub, perennial herbaceous, sagebrush, shrub, and tree, in addition to the temporal trends of each component. Several enhancements were made to the RCMAP process relative to prior generations. First, we have trained time-series predictions directly from 331 high-resolution sites collected from 2013-2018 from Assessment, Inventory, and Monitoring (AIM) instead of using the 2016 “base” map as an intermediary....
The RCMAP (Rangeland Condition Monitoring Assessment and Projection) dataset quantifies the percent cover of rangeland components across the western U.S. using Landsat imagery from 1985-2020. The RCMAP product suite consists of eight fractional components: annual herbaceous, bare ground, herbaceous, litter, non-sagebrush shrub, perennial herbaceous, sagebrush, shrub and rule-based error maps including the temporal trends of each component. Several enhancements were made to the RCMAP process relative to prior generations. We used an updated version of the 2016 base training data, with a more aggressive forest mask and reduced shrub and sagebrush cover bias in pinyon-juniper woodlands. We pooled training data in areas...
The need to monitor change in sagebrush steppe is urgent due to the increasing impacts of climate change, shifting fire regimes, and management practices on ecosystem health. Remote sensing provides a cost-effective and reliable method for monitoring change through time and attributing changes to drivers. We report an automated method of mapping rangeland fractional component cover over a large portion of the Northern Great Basin, USA, from 1986 to 2016 using a dense Landsat imagery time series. 2012 was excluded from the time-series due to a lack of quality imagery. Our method improved upon the traditional change vector method by considering the legacy of change at each pixel. We evaluate cover trends stratified...
Soil evaporation, a critical ecohydrological process in drylands, can exhibit substantial spatio-temporal variation. Spatially, ecohydrological controls of soil evaporation may generally depend on a hierarchical structure spanning from the presence or absence of litter, through canopy patches of woody plants and intercanopy patches separating them, up to the overall vegetation mosaic characterized by density of woody plant cover in the landscape, although assessment of these factors in concert is generally lacking. Temporally, ecohydrological controls can be further complicated by not only seasonal climate, but also phenology, particularly in seasonally deciduous drylands. We experimentally assessed the interactive...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Journal of Arid Environments,
canopy cover,
drylands,
ecohydrology,
hemispherical photography,
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