The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Elissa R. Levine - One of the best experts on this subject based on the ideXlab platform.
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Soil Saturation effects on forest dynamics: scaling across a southern boreal/northern hardwood landscape
Landscape Ecology, 1999Co-Authors: John F. Weishampel, Robert G. Knox, Elissa R. LevineAbstract:Patch modeling can be used to scale-up processes to portray landscape-level dynamics. Via direct extrapolation, a heterogeneous landscape is divided into its constituent patches; dynamics are simulated on each representative patch and are weighted and aggregated to formulate the higher level response. Further extrapolation may be attained by coarsening the resolution of or lumping environmental data (e.g., climatic, edaphic, hydrologic, topographic) used to delimit a patch. Forest patterns at the southern boreal/northern hardwood transition zone are often defined by Soil heterogeneity, determined primarily by the extent and duration of Soil Saturation. To determine how landscape-level dynamics predicted from direct extrapolation compare when coarsening Soil parameters, we simulated forest dynamics for Soil series representing a range of drainage classes from east- central Maine. Responses were aggregated according to the distribution of Soil associations comprising a 600 ha area based on local- (1:12,000), county- (1:120,000) and state- (1:250,000) scale Soil maps. At the patch level, simulated aboveground biomass accumulated more slowly in poorer draining Soils. Different Soil series yielded different communities comprised of species with various tolerances for Soil Saturation. When aggregated, removal of waterlogging caused a 20–60% increase in biomass accumulation during the first 50 years of simulation. However, this early successional increase and the maximum level of biomass accumulation over a 200 year period varied by as much as 40% depending on the geospatial data. This marked discrepancy suggests caution when extrapolating with forest patch models by coarsening parameters and demonstrates how rules used to rescale environmental data need to be evaluated for consistency.
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Soil Saturation effects on forest dynamics: scaling across a southern boreal/northern hardwood landscape
Landscape Ecology, 1999Co-Authors: John F. Weishampel, Robert G. Knox, Elissa R. LevineAbstract:Patch modeling can be used to scale-up processes to portray landscape-level dynamics. Via direct extrapolation, a heterogeneous landscape is divided into its constituent patches; dynamics are simulated on each representative patch and are weighted and aggregated to formulate the higher level response. Further extrapolation may be attained by coarsening the resolution of or lumping environmental data (e.g., climatic, edaphic, hydrologic, topographic) used to delimit a patch.
John F. Weishampel - One of the best experts on this subject based on the ideXlab platform.
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Soil Saturation effects on forest dynamics: scaling across a southern boreal/northern hardwood landscape
Landscape Ecology, 1999Co-Authors: John F. Weishampel, Robert G. Knox, Elissa R. LevineAbstract:Patch modeling can be used to scale-up processes to portray landscape-level dynamics. Via direct extrapolation, a heterogeneous landscape is divided into its constituent patches; dynamics are simulated on each representative patch and are weighted and aggregated to formulate the higher level response. Further extrapolation may be attained by coarsening the resolution of or lumping environmental data (e.g., climatic, edaphic, hydrologic, topographic) used to delimit a patch. Forest patterns at the southern boreal/northern hardwood transition zone are often defined by Soil heterogeneity, determined primarily by the extent and duration of Soil Saturation. To determine how landscape-level dynamics predicted from direct extrapolation compare when coarsening Soil parameters, we simulated forest dynamics for Soil series representing a range of drainage classes from east- central Maine. Responses were aggregated according to the distribution of Soil associations comprising a 600 ha area based on local- (1:12,000), county- (1:120,000) and state- (1:250,000) scale Soil maps. At the patch level, simulated aboveground biomass accumulated more slowly in poorer draining Soils. Different Soil series yielded different communities comprised of species with various tolerances for Soil Saturation. When aggregated, removal of waterlogging caused a 20–60% increase in biomass accumulation during the first 50 years of simulation. However, this early successional increase and the maximum level of biomass accumulation over a 200 year period varied by as much as 40% depending on the geospatial data. This marked discrepancy suggests caution when extrapolating with forest patch models by coarsening parameters and demonstrates how rules used to rescale environmental data need to be evaluated for consistency.
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Soil Saturation effects on forest dynamics: scaling across a southern boreal/northern hardwood landscape
Landscape Ecology, 1999Co-Authors: John F. Weishampel, Robert G. Knox, Elissa R. LevineAbstract:Patch modeling can be used to scale-up processes to portray landscape-level dynamics. Via direct extrapolation, a heterogeneous landscape is divided into its constituent patches; dynamics are simulated on each representative patch and are weighted and aggregated to formulate the higher level response. Further extrapolation may be attained by coarsening the resolution of or lumping environmental data (e.g., climatic, edaphic, hydrologic, topographic) used to delimit a patch.
Robert G. Knox - One of the best experts on this subject based on the ideXlab platform.
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Soil Saturation effects on forest dynamics: scaling across a southern boreal/northern hardwood landscape
Landscape Ecology, 1999Co-Authors: John F. Weishampel, Robert G. Knox, Elissa R. LevineAbstract:Patch modeling can be used to scale-up processes to portray landscape-level dynamics. Via direct extrapolation, a heterogeneous landscape is divided into its constituent patches; dynamics are simulated on each representative patch and are weighted and aggregated to formulate the higher level response. Further extrapolation may be attained by coarsening the resolution of or lumping environmental data (e.g., climatic, edaphic, hydrologic, topographic) used to delimit a patch. Forest patterns at the southern boreal/northern hardwood transition zone are often defined by Soil heterogeneity, determined primarily by the extent and duration of Soil Saturation. To determine how landscape-level dynamics predicted from direct extrapolation compare when coarsening Soil parameters, we simulated forest dynamics for Soil series representing a range of drainage classes from east- central Maine. Responses were aggregated according to the distribution of Soil associations comprising a 600 ha area based on local- (1:12,000), county- (1:120,000) and state- (1:250,000) scale Soil maps. At the patch level, simulated aboveground biomass accumulated more slowly in poorer draining Soils. Different Soil series yielded different communities comprised of species with various tolerances for Soil Saturation. When aggregated, removal of waterlogging caused a 20–60% increase in biomass accumulation during the first 50 years of simulation. However, this early successional increase and the maximum level of biomass accumulation over a 200 year period varied by as much as 40% depending on the geospatial data. This marked discrepancy suggests caution when extrapolating with forest patch models by coarsening parameters and demonstrates how rules used to rescale environmental data need to be evaluated for consistency.
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Soil Saturation effects on forest dynamics: scaling across a southern boreal/northern hardwood landscape
Landscape Ecology, 1999Co-Authors: John F. Weishampel, Robert G. Knox, Elissa R. LevineAbstract:Patch modeling can be used to scale-up processes to portray landscape-level dynamics. Via direct extrapolation, a heterogeneous landscape is divided into its constituent patches; dynamics are simulated on each representative patch and are weighted and aggregated to formulate the higher level response. Further extrapolation may be attained by coarsening the resolution of or lumping environmental data (e.g., climatic, edaphic, hydrologic, topographic) used to delimit a patch.
Hiroshi Fukuoka - One of the best experts on this subject based on the ideXlab platform.
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A distributed hydrological-geotechnical model using satellite-derived rainfall estimates for shallow landslide prediction system at a catchment scale.
Landslides, 2010Co-Authors: Apip, Kaoru Takara, Yosuke Yamashiki, Kyoji Sassa, Agung Bagiawan Ibrahim, Hiroshi FukuokaAbstract:This paper describes the potential applicability of a hydrological–geotechnical modeling system using satellite-based rainfall estimates for a shallow landslide prediction system. The physically based distributed model has been developed by integrating a grid-based distributed kinematic wave rainfall-runoff model with an infinite slope stability approach. The model was forced by the satellite-based near real-time half-hourly CMORPH global rainfall product prepared by NOAA-CPC. The method combines the following two model outputs necessary for identifying where and when shallow landslides may potentially occur in the catchment: (1) the time-invariant spatial distribution of areas susceptible to slope instability map, for which the river catchment is divided into stability classes according to the critical relative Soil Saturation; this output is designed to portray the effect of quasi-static land surface variables and Soil strength properties on slope instability and (2) a produced map linked with spatiotemporally varying hydrologic properties to provide a time-varying estimate of susceptibility to slope movement in response to rainfall. The proposed hydrological model predicts the dynamic of Soil Saturation in each grid element. The stored water in each grid element is then used for updating the relative Soil Saturation and analyzing the slope stability. A grid of slope is defined to be unstable when the relative Soil Saturation becomes higher than the critical level and is the basis for issuing a shallow landslide warning. The method was applied to past landslides in the upper Citarum River catchment (2,310 km2), Indonesia; the resulting time-invariant landslide susceptibility map shows good agreement with the spatial patterns of documented historical landslides (1985–2008). Application of the model to two recent shallow landslides shows that the model can successfully predict the effect of rainfall movement and intensity on the spatiotemporal dynamic of hydrological variables that trigger shallow landslides. Several hours before the landslides, the model predicted unstable conditions in some grids over and near the grids at which the actual shallow landslides occurred. Overall, the results demonstrate the potential applicability of the modeling system for shallow landslide disaster predictions and warnings.
John D. Albertson - One of the best experts on this subject based on the ideXlab platform.
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Simulating the spatio-temporal dynamics of Soil erosion, deposition, and yield using a coupled sediment dynamics and 3D distributed hydrologic model
Environmental Modelling & Software, 2016Co-Authors: Mukesh Kumar, Gerard Kiely, Ciaran Lewis, John D. AlbertsonAbstract:Since Soil erosion is driven by overland flow, it is fair to expect heterogeneity in erosion and deposition in both space and time. In this study, we develop and evaluate an open-source, spatially-explicit, sediment erosion, deposition and transport module for the distributed hydrological model, GEOtop. The model was applied in Dripsey catchment in Ireland, where it captured the total discharge volume and suspended sediment yield (SSY) with a relative bias ofź-1.2% andź-22.4%, respectively. Simulation results suggest that daily SSY per unit rainfall amount was larger when the top Soil was near Saturation. Simulated erosion and deposition areas, which varied markedly between events, were also found to be directly influenced by spatial patterns of Soil Saturation. The distinct influence of Soil Saturation on erosion, deposition and SSY underscores the role of coupled surface-subsurface hydrologic interactions and a need to represent them in models for capturing fine resolution sediment dynamics. An open-source, spatially-explicit, sediment dynamics model was developed.The model was validated at both plot and catchment scales.Error in runoff estimates influences the accuracy of simulated suspended sediment yield.Daily precipitation intensity did not fully explain the variance in daily SSY.Simulated spatial patterns of erosion/deposition were influenced by surface Soil Saturation.