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4.5 Cumulative Habitat Length and QualityUpstream - Downstream Habitat Length and Quality
Parameter Description: A calculation that provides a length-weighted average or sum of habitat length or quality in every reach in NetMap’s river networks. The point of reference can be any location in a river network and viewing the result either upstream or downstream. For example, "upstream" refers the sum (or average) of all reaches upstream of any particular reach; in Figure 1 the upstream summed value at the point of reference would be 2.0, while the summed downstreasm value from the point of reference would be 1.6. Each channel segment contains both indices for any parameter of interest (refer to the Upstream-Downstream routing tool).
Data Type: Reach
Units: Habitat quality score and length (m)
NetMap Module/Tool: Aquatic Habitats
Model Description:
NetMap contains a tool for calculating the length-weighted average or sum of habitat length or quality (or for any reach parameter) at every reach in the river network (Figure 1). The point of reference can be any reach (looking upstream or downstream). The cumulative upstream habitat quality or length is species specific and is based on the defined fish bearing network. The cumulative upstream habitat length parameter is also used in NetMap’s Road Tools where habitat length upstream of each road crossing can be calculated. The tool interface in NetMap allows for numerous options (Figure 2).
 Figure 1. The length-weighted average or sum of any habitat attribute is calculated for each reach (e.g., upstream and downstream from each reach).
 Figure 2. (1) A category of attributes is selected; aquatic habitat is the default. (2) An attribute is selected such as coho salmon intrinsic potential. (3) The attribute name and units are displayed in the interface. Users can select only the fish bearing network (4), to reset values at lakes (5), to analyze reaches upstream (6) or downstream (7); the output shown is the result of analyzing reaches upstream. The analysis can include the length-weighted mean, summed value, total length or calculated at road crossings only.
 Figure 3. NetMap can calculate the cumulative upstream habitat length for each and every segment in the defined fish bearing network.
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