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TitleRiver sediment capture
CustodianWater and Marine Resources Division, Department of Primary Industries, Parks, Water and Environment
CreatorGIS Unit, Information and Land Services Division, Department of Primary Industries and Water
DescriptionAn index which provides a relative measure of reduced sediment transport in rivers through capture within dams.
Input data
Lineage
Changes in the natural sediment regime caused by human disturbance can result in both increases and decreases in sediment loads and transport rates. A primary control of reduced sediment transport is capture within dams. This was used as the basis of an index of sediment capture in river systems, in the absence of reliable models which could also assess changes in sediment storage in channels and floodplains.
Values of the regulation index for rivers were used as a surrogate for a sediment capture index. A pre-processing step was undertaken to convert the regulation data to a 0-1 scale (see below). This index was then used as a direct input into the rivers geomorphic condition expert rule system.
Date createdNovember 2004
Scale and coverage1:25 000; Statewide
Column headingRS_SEDCA
Type of dataContinuous but has been converted to categorical format (see Table 1).
Number of classes3
Assigning values to ecosystem spatial units
The regulation attribute data for rivers (RS_REGI) was pre-processed to convert the original data, using the data integration program (MatLab), to a 0-1 scale prior to being input to any expert rules system, where:
HIGH = 0-0.1, MEDIUM = 0.1-0.8 and LOW = >0.8
The output data from this step was subsequently assigned to the river spatial units as RS_SEDCA.
The rivers spatial data layer had the continuous sediment capture data categorised according to Table 1. The categorical data was used for reporting and mapping purposes.
Table 1. Sediment capture categories for rivers.
Category | Min to max values |
Low | 0 to <0.1 |
Medium | 0.1 to <0.8 |
High | 0.8 to 1 |
CFEV assessment framework hierarchy