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Kickoff Meeting, Project “Mirage - Mediterranean Intermittent River ManAGEment”, 2009
Citation preview
Channel head locationChannel head locationusing DEMsusing DEMs
Meeting in Bari • 22-24 September ’09
Autorità di Bacino della PugliaLR 9 dicembre 2002c/o InnovaPuglia S.p.A.www.adb.puglia.it
Politecnico di BariDipartimento di Ingegneria delle Acquee di Chimicawww.diac.poliba.it
CHANNEL HEADS
EXTENTOF CHANNEL NETWORK
Geomorphic &
HydrologicAnalyses
EnvironmentalManagement
CHANNEL NETWORK OF APULIA REGION
Estimating channel head location according scientific basis
KEY ASSUMPTIONS
LandscapeGeomorphologic form
Erosionprocesses
DYNAMIC EQUILIBRIUMbetween
SOIL PROPERTY&
CLIMATE REGIME
Channel network rapresents indeed the mark on landscapeof intermittent discharge series of flow and sediment transport
Estimating channel head location according scientific basis
KEY ASSUMPTIONS
LandscapeGeomorphologic form
Erosionprocesses
DEM analysis
Dominant sediment and transport
process
+Geomorphologic thresholds
GEOMORPHOLOGICTHRESHOLDS
= ƒ ( A, S)
Drainage Area
Surface slope
Drivers of erosion processesBut also
Indicators of past erosive actions
Estimating channel head location according scientific basis
PILOT CATCHMENT
UTM CoordinateE = 593735,06 N = 4638391,50
A = 27 SKm
BasA
EASTERN GARGANO
0.300
0.400
0.500
0.600
0.700
0.800
0.900
1.000
0.00000 0.20000 0.40000 0.60000 0.80000 1.00000
Ai / A
h i
/ h m
ax
h media
Absance of tectonic forces
Soil impermeability
MATURESTAGE
DTM 5 x 5 m
Fill Dem
Slope
Flow Directions
Flow accumulation
Energy Index
TWI
TURNOVER
40 pixel=
1100 mq
0>dAdS
0<dAdS
0.010
0.100
1.000
1 10 100 1000 10000 100000
Drainage Area [pixel]
Lo
ca
l S
lop
e [
m/m
]
n
SLOPE-AREA PLOT AvsP
[Gilbert] slope-dependent sediment transport gives rise toCONVEX PROFILE
Discharge and slope dependent sediment transport gives rise to CONCAVE PROFILES
Transition from CONVEX
to CONCAVE
profiles
=Transizione
HILLSLOPE - VALLEY
NO!! Channel Head
AvsP
TURNOVER
40 pixel=
1100 mq
0>dAdS
0<dAdS
AvsP
TURNOVER
40 pixel=
1100 mq
0>dAdS
0<dAdS
Transition from CONVEX
to CONCAVE
profiles
=Transition
HILLSLOPE - VALLEY
NO!! Channel Head
0,010
0,100
1,000
1 10 100 1000 10000 100000
Area drenata [pixel]
Pe
nd
en
za lo
ca
le [
m/m
]
0,010
0,100
1,000
1 10 100 1000 10000 100000
Area drenata [pixel]
Pe
nd
en
za lo
ca
le [
m/m
]
SA1
0,010
0,100
1,000
1 10 100 1000 10000 100000
Area drenata [pixel]
Pe
nd
en
za lo
ca
le [
m/m
]
SA1
y = 1,2354x-0,3257 R2 = 0,3192
0.010
0.100
1.000
1 10 100 1000 10000 100000
Area drenata [pixel]
Pen
den
za l
oca
le [
m/m
]
potenza1
SA1 SA2
y = 1,2354x-0,3257 R2 = 0,3192
0.010
0.100
1.000
1 10 100 1000 10000 100000
Area drenata [pixel]
Pen
den
za
local
e [m
/m]
potenza1
SA1 SA2 SA3
SA1 = 40 pixel
SA2 = 200 pixel
SA3 = 1100 pixel
AvsP
CUMULATIVE AREA DISTRIBUTION PLOT
0,001
0,01
0,1
1
1 10 100 1000 10000 100000
A* [pixel]
P(A
>A
*)
SA1 = 40 pixel CAD1
0,001
0,01
0,1
1
1 10 100 1000 10000 100000
A* [pixel]
P(A
>A
*)
CAD1
y = 11,685x-1,2068 R2 = 0,9994
0,001
0,01
0,1
1
1 10 100 1000 10000 100000
A* [pixel]
P(A
>A
*)
potenza1
CAD1
SA3 = 1100 pixel CAD2
0,001
0,01
0,1
1
1 10 100 1000 10000 100000
A* [pixel]
P(A
>A
*)
CAD1 CAD2
y = 0,5267x-0,4825 R2 = 0,9969
0,001
0,01
0,1
1
1 10 100 1000 10000 100000
A* [pixel]
P(A
>A
*)
potenza2
CAD1 CAD2
≅ -0,43 fluvial channel
CAD
ENERGY INDEX DISTRIBUTION PLOT
0,0001
0,001
0,01
0,1
1
1,000 10,000 100,000
Energy Index EI*
P(E
I>E
I*)
ASEI ⋅=
0,0001
0,001
0,01
0,1
1
1,000 10,000 100,000
Energy Index EI*
P(E
I>E
I*)
EID10,0001
0,001
0,01
0,1
1
1,000 10,000 100,000
Energy Index EI*
P(E
I>E
I*)
EID1 EID2
Slope-dependent crtical contributing area
EID
2)(tanϑC
Acr =
EID
25.0 24
=⇒=⋅=S
AASEI2
5.0 1020
=⇒=⋅=S
AASEI
EID1 EID2
ENERGY INDEX DISTRIBUTION PLOT
0,0001
0,001
0,01
0,1
1
1,000 10,000 100,000
Energy Index EI*
P(E
I>E
I*)
EID1 EID2
Slope-dependent crtical contributing area
AvsPCADEID
0,01
0,1
1
1 10 100 1000 10000 100000
Area drenata [pixel]
Pe
nd
en
za lo
ca
le [
m/m
]
0,01
0,1
1
1 10 100 1000 10000 100000
Area drenata [pixel]
Pe
nd
en
za lo
ca
le [
m/m
]
SG1 SG20,01
0,1
1
1 10 100 1000 10000 100000
Area drenata [pixel]
Pe
nd
en
za lo
ca
le [
m/m
]
SG1 SG2 EID1
EID2
VERSANTI.basA: if(($tca.basA$<40),5,null)VALLI.basA: if(($tca.basA$>=40)&&($EI.basA$<4),4,null)HEAD.basA: if(($EI.basA$>=4)&&($ tca.basA$<1100),3,null)RETICOLO.basA: if($tca.basA$<1100,null,2)
y = 151,08e-0,9204x
R2 = 0,9473
y = 19,069e0,4895x
R2 = 0,9855
y = 351,38e1,4369x
R2 = 0,9741
1
10
100
1.000
10.000
100.000
1.000.000
1 2 3 4
u
Nu
,Lu
*,A
u
u vs. Nu u vs. Lu* u vs. Au
1 ̂legge di Horton 2 ̂legge di Horton legge di Schumm
0
5
10
15
20
25
0 0,5 1 1,5 2 2,5 3
t [h]
Q [
mc
/s]
RA
RB
RL
LGIUH
• Abrahms A.D.; Channel networks: A geomorphological perspective; Water Resources Research, 25, 29-49; 1984• Flint J.J.; Stream gradient as a function of order, magnitude and discharge; Water Resource Research, 10 (5), 969-973; 1974 • Gilbert G.K.; The convexity of hill tops; Journal of Geology, 17, 344-350; 1909• Kirkby M.J.; Hillslope process-response models based on the continuity equation; Institute of British Geographers, Special Publication, 3, 15-30; 1971• Kirkby M.J.; The stream head as a significant geomorphic threshold; Thresholds in Geomorphology, Allen & Unwin, 53-73; 1980• McNamara J.P., Ziegler A.D., Wood S.H., Vogler J.B.: Channel head locations with respect to geomorphologic thresholds derived from a digital elevation model: A casa study in northern Thailand; Forest Ecology and Management, 224, 147-156; 2006• Montgomery D.R., Dietrich W.E.; Source areas, drainage density and channel initiation; Water Resource Research, 25, 1907-1918; 1989• Montgomery D.R., Foufoula-Georgiou E.; Channel network source representation using digital elevation models; Water Resources Research, 29, 12, 3925-3934; 1993• Rodriguez-Iturbe I., Rinaldo A., Rigon R., Bras R.L., Marani A., Ijjasz-Vasquez E.; Energy dissipation, runoff, and the three-dimensional structure of river basins; Water Resources Research, 28 (4), 1095-1103; 1992a
Bari, 24/09/2009
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