Steps: 1. Pre-processing Fill depressions Flow direction Flow accumulations 2. Stream definition...
4
Catchment delineation rocess in creating sub-catchment polygons Zhang CAROLINA NORTH Steps: 1. Pre-processing Fill depressions Flow direction Flow accumulations 2. Stream definition (fig. a) Number of cells – 150 Areas – 0.015118 Km 2 2. Stream segmentation 3. Catchment delineation (Fig. b) 4. Catchment polygons (Fig. b) Fig. a) Stream Fig. b) Polygons
-
Upload
lynette-white -
Category
Documents
-
view
217 -
download
1
Transcript of Steps: 1. Pre-processing Fill depressions Flow direction Flow accumulations 2. Stream definition...
Catchment delineationProcess in creating sub-catchment polygons
Zhang
CAROLINA NORTH
Steps: 1. Pre-processing Fill depressions Flow direction Flow accumulations2. Stream definition (fig. a) Number of cells – 150 Areas – 0.015118 Km2
2. Stream segmentation3. Catchment delineation (Fig. b)4. Catchment polygons (Fig. b)
Fig. a) Stream
Fig. b) Polygons
Soil ErosionRelative Stream Power & Downslope Change
Zhang
Fig. c) Relative Stream Power (RSP)
Fig. d) Downslope change
To measure the change of the slope, defined as the derivative of relative stream power. The higher the value is, the larger extent the stream power changes and thus the easier the soil erosion happens.
RSP = As ^ 1.0 * tan(S) As: specific catchment area S: local slopeA measure of the erosive power of flowing stream network.
Relative Stream Power
Downslope change
Soil ErosionAnalysis of Downslope Change
Zhang
Fig. e) Selected catchments
High values of dRSPdx: 33 catchments soil erosion are potentially to happen conifer
Low downslope change: 94 catchments sediment are potentially to deposit impervious surface other land cover
Catchment selection
Soil ErosionAnalysis of Downslope Change
Zhang
