Developing GIS indicators and metrics
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Developing GIS indicators Developing GIS indicators and metrics and metrics David Theobald Natural Resource Ecology Lab Colorado State University
description
Developing GIS indicators and metrics. David Theobald Natural Resource Ecology Lab Colorado State University. Goals of indicator development. Develop and evaluate landscape-level indicators suitable for spatial and temporal analyses of EMAP data - PowerPoint PPT Presentation
Transcript of Developing GIS indicators and metrics
Developing GIS indicators and metricsDeveloping GIS indicators and metrics
David TheobaldNatural Resource Ecology Lab
Colorado State University
Goals of indicator developmentGoals of indicator development
Develop and evaluate landscape-level indicators suitable for spatial and temporal analyses of EMAP data
Investigate limitations of currently-available data and offer new, robust methodologies
Current effortCurrent effort
1. Linkage between watershed and hydrologic networks
2. Refine surrogates with direct measures of area and discharge
3. GIS-based toolsa. RWTools for ArcViewb. Catchment delineation & discharge in
ArcGIS
1. Watershed–hydrological 1. Watershed–hydrological network linkagenetwork linkage“…in every respect, the valley rules
the stream.” – Hynes 1975Indirect measures based on
hydrological properties (e.g., Strahler order, drainage density, etc.)
Distance:Distance:
As the crow flies (Euclidean)
Distance:Distance:
As the crow flies As the seed floats
(downstream)
Distance:Distance:
As the crow flies As the seed floats As the fish swims
(down & up stream)
Distance:Distance:
As the crow flies As the seed floats As the fish swims
(down & up stream) Upstream length
- mainstem (2)- arbolate (1+2+3+4)
Distance:Distance:
As the crow flies As the seed floats As the fish swims Upstream length Network (dams,
fragmentation)
What indicators measure What indicators measure watershed-stream linkage?watershed-stream linkage?Length of stream line– Dam alteration of flow at a downstream
gauge?
RWTools extension (ArcView v3.2)
Upstream66 km
Downstream298 km
MainstemUpstream37 km
Network16 km (down)6 km (up)
2. Direct measures of discharge 2. Direct measures of discharge
Surrogates developed, e.g. Strahler order: The usefulness of stream order assumes, with a sufficiently large sample, that order is proportional to stream discharge – Strahler 1957
Alternatives:- basin area- discharge
Delineate reach catchmentsDelineate reach catchments
Robust method (no pre-processing)1 to 1 relationship NHD reach and
catchment“Grow” watershed from reach line
based on flow direction iteratively
Stream dischargeStream discharge
PrecipitationD = C * P
10 acft
8 acft20 acft
R2=0.7282
P-value=3.407e-006
Stream dischargeStream discharge
Encouraging preliminary resultsAdditional factors (Infiltration, E.T.): – Geology– Land cover– Exposure
D = f(C, G, L, E)
3. GIS-based tools3. GIS-based tools
Interactive query and analysis of watersheds (RWTools) (ArcView v3.2)
ArcGIS Geometric network
Plans for next yearPlans for next year
Initial release of GIS tools:– RWTools for ArcGIS– Functional-based spatial weights
Spatial weightsSpatial weights
11 2
3 54
0 0 0 0 0
0 0 0 0 0
0 0 0 0 0
1 0 1 0 0
0 1 0 1 0
W =
Functional weighting Functional weighting
1
1 2 3
54
0 0 0 0 0 0 0
0.7 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0.7 0 0 0
0.2 0.8 0 0.2 0.8 0 0
0.1 0.2 1.0 0.1 0.2 1.0 0
W =
6 7
E.g., downstream hydrology
Functional weighting Functional weighting
1
1 2 3
54
0 1 0 0 0 0 0
1 0 0 0 1 1 0
0 0 0 0 0 0 0
0 0 0 0 1 0 0
0 1 0 1 0 1 0
0 1 0 0 1 0 1
0 0 0 0 0 1 0
W =
6 7
E.g., macroinvertebrates
Plans for next yearPlans for next year
Initial release of GIS tools:Perennial/intermittent frame
problem in western USDevelopment of network
fragmentation indices
