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ForestERA Metadata - Crown Base Height |
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AbstractThese are 90m resolution raster datases describing crown base height across the western Mogollon Plateau in Arizona. They were created as part of the Forest Ecosystem Restoration Analysis (ForestERA) project to support landscape-scale forest restoration planning efforts by a broad group of stakeholders including federal and state agencies, academic institutions, and non-governmental entities. PurposeThese layers were developed by the ForestERA project for use in landscape-level planning and prioritization of forest management on the western Mogollon Plateau. They were designed to be used primarily in fire behavior modeling and forest management planning. This layer, converted to ascii format, is ready for use in the FlamMap and FARSITE fire behavior modeling programs. Supplementary InformationThese layers were created using the quadratic mean diameter (QMD) layer developed by the ForestERA team. Attributes of the tree canopy cannot be directly measured using readily available and inexpensive types of remote-sensing imagery. Because of this, it was necessary to use allometric equations to develop this layer. Mean values of crown base height for individual trees are strongly correlated to the mean diameter at breast height (DBH) of those trees. Since DBH and QMD are related measures (QMD = DBH when all trees in the QMD analysis are of equal DBH), we were able to use our QMD layer and linear regression equations to estimate mean crown base height across the region. No accuracy assessment is possible for these layers, as we do not have comprehensive measurements of crown base height across this region. The use of this methodology resulted in reasonable values for mean crown base height. However, we note that there are accuracy issues with the QMD layer (see the metadata for that layer), and that all of these attributes may vary widely across the region depending on actual tree size class distributions, management history, and other factors. We do not believe these layers are highly accurate and we recommend using them with caution. These data are intended for regional analyses over spatial extents on the order of tens to hundreds of thousands of acres, and were not developed for use at finer spatial scales, although they may be useful for some applications at those finer scales. _________________ Status of the dataComplete Time period for which the data is relevantDate and time: Publication InformationWho created the data: Forest Ecosystem Restoration Analysis Project Date and time: February 1, 2004 Data storage and access informationFile name: meancbh90m Location of the data:\\ENVSCI41\Shared\metadata_layers\grids\meancbh90m Accessing the dataSize of the data: 22.970 MB Constraints on accessing and using the dataAccess constraints: This layer may be accessed by any interested party.
It is Use constraints: Details about this documentContents last updated: 20040421 at time 14340300 Northern Arizona University 928-523-0068 (voice) Contact Instructions:Contact Dr. Thomas D. Sisk or the Forest Ecosystem Restoraton Analysis Project. Standards used to create this documentStandard name: FGDC Content Standards for Digital Geospatial Metadata Horizontal coordinate system Projected coordinate system name: NAD_1983_UTM_Zone_12N Planar Coordinate Information Planar Distance Units: meters Geodetic Model Horizontal Datum Name: North American Datum of 1983 Bounding coordinates Horizontal Spatial data description Raster dataset information No detailed attribute information is available. Page last updated February 11, 2005 |
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