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KRIS Big River Map Project:  Land Cover View

The Land Cover View in the KRIS Big River Map project provides a wealth of spatial data for watershed assessment such as vegetation stand conditions, road locations, period of construction and ownership. For establishing location and a sense of topography, this view has Calwater watershed boundaries, a USGS topographic map, a digital elevation map, and a partially tiled aerial mosaic (DOQQ) of the North Fork Big River watershed from 1993 photos. The vegetation themes, derived from a 1994 Landsat image by the USFS  Spatial Analysis Lab in Sacramento, can be queried by tree size or by community type (see Vegetation Types background page). The California Department of Forestry Fire and Resource Assessment Program provided change scene detection, which compares a 1994 Landsat image with one captured in 1998 (Fisher, in press).

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 This image, from the KRIS Big River Map project, shows USFS vegetation coverage derived from 1994 Landsat imagery for the entire basin. Much of the South Fork landscape is characterized as early seral stands with non-forest (grass/shrubs/bare soil) and saplings (trees 2-4.9" diameter) due to recent logging. Large non-forest components in the east and west are naturally occurring grasslands and the coastal terrace, respectively. Much of the central portion of the watershed has substantial components of  small-medium (12-19.9") and medium/large trees (20-29.9") interspersed with patches of small trees (5-11.9") indicating a more mature forest than in the South Fork. 

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 The image at left is from the KRIS Big River Map project and shows changes in vegetation from 1994 to 1998 based on Landsat images from both periods. These data come from CDF FRAP (Fisher, in press) and show logging in the North Fork and lower main Big River during this period, with more extensive cover removal of showing in deeper oranges and reds. Re-growth of vegetation shows as shades of light green. 
landcov_big1.gif (68782 bytes)  The image at left is from the EPA Land Cover project, which is included in the KRIS Big River Map project. The sand dunes of the beach show as bare rock in the west, and pastureland is also strongly represented. The northeastern portion of the watershed shows as grasslands, shrubland and mixed forest due to earthflow terrain in this region. Patches of mixed forest and shrubland disbursed throughout the watershed reflect early seral conditions after timber harvest. 
doqq1.gif (397914 bytes) The image at left is from a 1993 digital orthophoto quarter quad that was obtained through the Advanced Spatial Analysis Facility at Humboldt State University. It  shows the North Fork Big River basin with recent cuts showing prominently, and older cuts appearing less distinct. This theme is useful in watershed assessment as a reference for what ground conditions are like. 
roads24k_big1.gif (105389 bytes) The map at left shows roads at a scale of 1:100k in the Big River basin. The road network was significantly expanded in the period between 1988 and 1999. Image taken from the KRIS Map ArcView project. The U.S. Geologic Survey 1:24k DRG roads are also displayed.
rdstmxings_big.gif (68443 bytes) The map at left shows road-stream crossings at a scale of 1:24k in the Big River Basin. Image taken from the KRIS Big River Map ArcView project, derived from roads layer provided by CDF. 
rds2stms_big.gif (70057 bytes)  The image at left shows the lengths of road within 10 and 30 meters of streams. Both these themes were developed by KRIS staff based on USGS 1:24,000 hydrography and roads coverages, which under-estimate small streams and recently built roads. The patterns of red and yellow lines following major tributaries indicate that roads are located in riparian zones. 


Warbington, R., B. Schwind, C. Curlis and S. Daniel. 1998. Creating a Consistent and Standardized Vegetation Database for Northwest Forest Plan Monitoring in California. USDA Forest Service. Pacific Southwest Region Remote Sensing Lab. Sacramento, CA.