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Climate Change & Impact of Sea Level Rise on Landuse Suitability
Presented by
S.H.M. FakhruddinTechnical Specialist, ADPC
mailto:[email protected]
Objectives of the study
To assess the Climate Change Impacts of Sea
Level Rise on the Land Use and Livelihood
To assess the Climate Change Impacts of Sea To assess the Climate Change Impacts of Sea
Level Rise on the Land Use and LivelihoodLevel Rise on the Land Use and Livelihood
Review of Adaptation Options Review of Adaptation Options Review of Adaptation Options
This study was conducted in 2004-05 under CEGIS, Bangladesh
Study areaDistricts:
SatkhiraKhulna Bagerhat
Thanas: 29
S u n d a r b a n s
Effects of sea level rise on the coastline of Bangladesh
Literature ReviewLiterature Review
3m
3m
1m
1m
Source: Ali, S.I. and S. Huq, 1989
The Conceptual Framework
Hazards Flooding Cyclone Salinity
Water Logging
Sea Level Rise Adaptation
Practices/ Mediating Factor
Physical Social
Economic Institutional
Land Water Suitability
Livelihoods
Land Use
Asset
Well-being
Water Resource SystemWater Resource System• Madhumati-Baleswar• Gorai-Rupsha-Pussur• Sibsha• Betna-Kobadak-Kolpetua
Base Condition
Methodology & Study Approach
Salinity Salinity SedimentationSedimentation Flooding DrainageFlooding DrainageConcentrationConcentration
Compute Changes in
Physical System Sea level rise
Scenario
Field Data
Other Studies
Evaluation of Adaptation Options
AndStrategy development
Suitability& Alternate Land Use
Review Problem Analysis
Compute Changes in
Physical System Sea level rise
Scenario
Field Data
Other Studies
Evaluation of Adaptation Options
AndStrategy development
Suitability& Alternate Land Use
Review Problem AnalysisLiterature Literature
Impacts
HydrodynamicSedimentationFlood and DrainageSalinity Intrusion Crops SuitabilityForest Suitability
Land and Water Use System
Surface Water Salinity
GW Salinity
Field and Other studies
Soil Salinity
Scenarios/Options
Models/ T
ools
Land and Water Use Suitability
Water Level
DEMLand Type
Water Level
Soil Properties
Duration
Drainage
Drainage Module
Relationship between soil map and natural drainage
Relationship between soil map and polder drainage
Soil Map
Land Type Soil Salinity
Land Type Map
DrainageMap
DEM
Inundation duration
GW
GISDrainage
Map
Scenarios
MIKE-11
Drainage Class
DEM
Criteria of Classification
GW
Compare
-Water Level-Min and Max
Min WL
Polder Area
Area ElevationCurve
Duration
Drainage Class
Drainage congestion
Pold
er W
L
Drainage Area
DEM Polder parameters
Flooding Module
HD Model
Scenarios/Options
Flood depth maps
Criteria-depth class-frequency-time
Soil map DEMDEM
Land Type
Land Type Transformation
Existing
With scenarios
Changes in Land Type
Land Type Mapping
Salinity Module
AD Model
Salinity concentration at Critical location
Crop knowledge
Field data/experience
GIS surfacing
Salinity surface/duration
GIS and Temporal data
Different scenarios
Crop Suitability Model -CROPSUIT
CROPSUIT
Suitability
LC (GIS Grid file)
SRDI soil map
Land Characteristics-LC Assumed constant in time dimension
Soil attribute database
Spatial Distribution
of LCDEM GW
Flood depth Salinity
Land Characteristics-LC Varies with SLR & adaptation option
SLR Senarios
Decision Criteria Maximum Weighted
average User defined
Suitability Matrix using Land Quality and Land
Characteristics (LQ & LC)
Adaptation options
Mathematical Model Result
Landuse Requirements
Land use type
Map Statistics/ Table
Forest health evaluation
ParametersDevelopment of
forest health evaluation criteria
and parameters
Expert
ConsultationForest cover Information
Evaluation ofForest Health Index
(Very Good, Good, Poor)
Literature Review
Flooding Salinity ConcentrationGeomorphic
featureDrainagedensity
SLR
Scenario
Adaptation
Options
ParametersDevelopment of
forest health evaluation criteria
and parameters
Expert
ConsultationForest cover Information
Evaluation ofForest Health Index
(Very Good, Good, Poor)
Literature Review
Flooding Salinity ConcentrationGeomorphic
featureDrainagedensity
SLR
Scenario
Adaptation
Options
Forest: Growth Index Modelling
Index (e.g. Sundri)Ind. Duration
Strong B B BSalinity Moderate B W G
Less G W BLow Medium High
Ind. Duration
Strong
Moderate
Less
Low Medium High
G
GG
G
B
G
B
B
B
Index (e.g. Gewa)
Present FutureSundri
Mud
f lats
(slo
pe)
High-tide water level
Low-tide water level
Rid
geso
rle v
ees
Back-swamps or basins
Mai
nr i
ver
chan
n el hoda
nol khagragolpata
keora/baen goran
Gewa
sundari
hargoza
Identify clusters based on different situation
Boro/ Boro-Rabi (Small farmer)
Bagda(Fishers)
Mixed (Wage labour)
T-Aman-Bagda
Golda
Rapidly changing/ Forest based livelihoods
T-Aman/ T-Aman/ Kharif
Physical (P)
Social (S)
Economic (E)
Very SuitableModerately SuitableNot Suitable
Relationship Building
P,S,E S SP,S P,EP,E
P,SSS S S P,S,EP,S,E P,S,E P,S,EP,S,E P,S,E S P,S,E
SuitableNot Suitable
NAPA Findings: Adaptations for Sea Level Rise
Current Adaptation Practices for Sea Level Rise Chittagong KhulnaConstruction of embankment/PolderingSalt PanningShrimp Farming(Bagda,Galda etc.)Use of pond water for household Deep tube well for drinking waterMix carfingSuggestion for future adaptation (vulnerabilities increases) Sea Level RiseLand use zoningEnsuring the normal flow of upstream waterRain Water HarvestingHill water storageIntregated wet land farmingFish culture in scientific wayCrabs rearing
Problem/issues for Climate Change Chittagong Khulna Rajshahi SylhetSalinity L HCyclone/ Tidal FloodDeforestationRainfallErosionDrainageWater shortageTemperature
Example of NAPA review
Aman area derived from multitemporal RADARSAT Standard
Beam images of 2001
Golda shrimp area using RADARSAT Fine beam images, 2000
Forest
• Sundri• Gewa• Goran• Passur• Kackra
The Topographical Distribution Elevation (m)
0.20%2.83%
10.49%
20.53%
28.79%
22.88%
10.44%
2.94%0.81%
0%
5%
10%
15%
20%
25%
30%
35%
0.0 - 0.5 0.5 - 1.0 1.0 -1.5 1.5 -2.0 2.0 - 2.5 2.5 - 3.0 3.0 -3.5 3.5 -4.0 > 4.0
Elevation (m,PWD)
DEM
Forest cover using RS
19921992 19961996
DoFDoF 1996199620012001--20032003
Evidence of Sea Level Rise in SW region
Water Level change at Hiron Point
0
0.1
0.2
0.3
0.4
0.5
1975 1979 1983 1987 1991 1995 1999 2003
Ann
ual m
ean
WL
(m, P
WD
) Rise of Water Level= 0.53 cm / year
Data used for the year : 1977 to 2000
Water level rise along Gorai-Rupsha-Passur System
y = -0.0377x + 5.7191
0
1
2
3
4
5
6
0 25 50 75 100 125 150
Distence from downstream end (Km)
Rat
e of
Wat
er le
vel r
ise
(mm
/yr)
River Systems
Figure 4.4: Downstream boundary of Pussur for different sea level rise conditions
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
24-Aug-00 26-Aug-00 28-Aug-00 30-Aug-00 01-Sep-00 03-Sep-00 05-Sep-00 07-Sep-00 09-Sep-00Time
Wat
er L
evel
(m,P
WD
)
SLR 0 cmSLR 14 cmSLR 32 cmSLR 88 cm
Hydrodynamic Model Results:• Water Levels• Discharge• Velocity• Salinity
Hydrodynamic Model Runs
D/S Boundary
U/S Boundary
Sedimentation
Bhairab_U
Kazibacha
L-Solmari
BetnaRupsa
Nabaganga
Pussur
Bhairab_U
Kazibacha
L-Solmari
BetnaRupsa
Nabaganga
Pussur
Zone of movements Change in Sedimentation rate
Flooding and Drainage
Base SLR 88 cm
Flood DepthLand class distribution under different Scenarios
27%
21%
26%
17%
8%
0%
17%
12%
26% 26%
18%
1%
7%6%
20%
29%31%
6%
0%
5%
10%
15%
20%
25%
30%
35%
Dry 0 - 30 cm 30 - 90 cm 90 - 180 cm 180 - 300 cm >300 cm
Are
a (%
)
Base SLR 32 cm SLR 88 cm
Submergence of Embankments
DrainagePolder 15
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
12:00 AM 2:24 AM 4:48 AM 7:12 AM 9:36 AM 12:00 PM 2:24 PM 4:48 PM 7:12 PM 9:36 PM 12:00 AM
Time
WL
(m+p
wd)
.
Polder WL_SLR88 cm River WL_SLR88 cm Polder WL_SLR32 cmRiver WL_SLR32 cm Polder WL_SLR00 cm River WL_SLR 00 cm
hBase = 2.19 m
hSLR32 cm = 2.1 hSLR88 cm = 1.73
TSLR88 cm = 6.5
TSLR32 cm = 6.8
TBase = 7 hrs
TSLR88 cm' = 7 hrs
TSLR32 cm' = 7.2 hrs
TBase' = 7.5 hrs
Drainage TimeTBase = 14.5 hrsTSLR32 cm = 14 hrsTSLR88 cm = 13.5 hrs
Head diffbase cond = 2.19 m 32 cm SLR = 2.1m88 cm SLR = 1.73 m
Salinity
Land use adaptationOptions: • Long term measures – Ganges barrage (OGDA option 8)• Mid term measure – Augmentation of Gorai flow (OGDA
option 7)• Construction of closures on main river systems (Pussur,
Shibsha and Kobadak rivers)• Raising embankments to prevent overtopping• Rehabilitation of drainage systems
Strategies: • Environmental: to ensure landuse as per landuse zone based on
physical suitability• Social: to maximize the social preferences, for example maximizing
paddy cultivation.• Economic: to maximize economic return through credit facilities and
other financial incentives to the farmer to grow most economically profitable crops-shrimp.
Salinity condition with adaptation
Suitability – T. Aman
Forest Suitability
Sundri
Land use Zones - Environment
Land use Zones - Environment
Land use Zones - Environment
Land use Zones - Social
Land use Zones - Social
Land use Zones - Economic
Land use Zones - Economic
Paddy Production
S u n d a r b a n s
Dominant plant distribution
Plant diversification in Sundarbans
Thank You
Courtesy to CEGIS, Bangladesh
Climate Change & Impact of Sea Level Rise on Landuse SuitabilityObjectives of the studyBase ConditionMethodology & Study ApproachCrop Suitability Model - CROPSUITForest health evaluationAman area derived from multitemporal RADARSAT Standard Beam images of 2001Golda shrimp area using RADARSAT Fine beam images, 2000ForestThe Topographical DistributionEvidence of Sea Level Rise in SW regionRiver SystemsHydrodynamic Model RunsSedimentationFlooding and DrainageFlood DepthSubmergence of EmbankmentsDrainageSalinitySalinity condition with adaptationSuitability – T. AmanForest Suitability