Analysts can incorporate remote sensing data on current streamside vegetation relating to shade, including conifer and hardwood basal area and tree height (using LEMMA ), into NetMap. These data are then used to determine the effects of current shade on in-stream thermal loading that will also take into account topography (shading), stream orientation, channel width and solar angle. The resulting shade-thermal loading index can be used to identfy areas where reduced shade may be impacting stream temperatures. A useful attribute in the context of restoration.Ĥ) In-Stream Thermal Refugia.This mutli-faceted tool allows users to investigate how topographic, river network and vegetation controls thermal refugia at the scale of watersheds. In the tool, sources of refugia include: 1) current shade-influenced thermal loading used to identify along-channel variation in cooler water conditions, 2) aggregated shade-influenced thermal loading used to identify tributary contributions of cooler water conditions to mainstem rivers, at confluences (and conversley to identify point sources of wamer water conditions) 3) the locations in channel adjacent areas where surface elevations are similar to channel elevations to identify side channels, oxbow lakes and wetlands (and bogs) and thus to identify provisional enhanced hyporheic exchange and thus cooler temperatures (this requires the use of the valley floor mapping tool described in 3 below) 4) floodplain width, as a proxy for increased hyporheic flow and 5) the downstream reach to reach variation in floodplain width, such that valley constrictions identify the potential for upwelling flow.ĥ) Watershed scale wood recruitment tool. Similar to the project scale wood recruitment tool currently in NetMap (e.g., physically based model), this tool allows users to predict the spatial variation (at 100 m reaches) of present day wood recruitment potential at the scale of watersheds, thus reflecting the history of natural forest growth, timber harvest, fire and other land uses such as agriculture. An important restoration and forest management tool, users can overlap this prediction with an index of fish habitat potential and quality to identify areas for restoration (high habitat potential, low wood loading) or enhanced protection (high habitat potential, high wood loading).Ħ) Valley Floor Mapping Tool. Users create a raster of valley floor surface elevations referenced to channel elevations to better define valley floors and their morphology, including the occurrence of floodplains, terraces, alluvial fans, side channels, oxbow lakes and wetlands (and bogs). This tool is used in the analysis of thermal refugia (tool #2 above). In urban planning, the tool can be used to consider impervious areas with respect to naturally wet areas along streams and rivers.ħ) New Stream Classification Tool. A new stream classification approach was developed for the US Fish and Wildlife Service in the Flint Hills Tall Grass Prairie in Kansas.Ĩ) Road hydrologic connectivity/surface erosion tool update.This update allows users to import their own GPS locations (point file) for road drainage structures, thereby making the road hydrologic connectivity and road surface erosion predictions more spatially accurate, using WEPP or GRAIP-Lite).ĩ) Surface Erosion Tool update.
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