Download Land use Change

Farzad Emami
Dept. of Geotechnology and
Geohydraulics, University of Kassel,
Kassel, Germany
November 2014
Contents
Introduction
Literature Review
Case Study
Methodology
Results
Conclusion
1
Introduction
Watershed Management Problems and Issues
 Land use changes in the upstream rise gradually the water uses.
 The urgent demands in the downstream cannot be supplied.
 The reservoir inflow decreases and subsequent watershed problems.
Effects
 The downstream network development mistakes
 Significant damages of Drought occurrence in different land uses
 Mis-utilizing the rights reservoir storage (operation rule curve)
2
Introduction
Watershed Management Problems and Issues
 Unsustainable development in crop cultivated area located in the
upstream
 More frequent occurrence of droughts and floods
(Climate Change)
Causes
(land use Change)
3
Introduction
Climate
Change
Land
Use
Change
Hydrologic
Changes
4
Literature Review
Climate Change
Climate
Change
According to IPCC (2001) studies, precipitation and
temperature change predictions shows great changes in
vulnerability of water resources systems.
impact on the watershed hydrology
Beyene et al. (2007), Yao and Georgakakos (2001) and
Rosenzweig et al., (2007).
impacts on rainfall- runoff
Varanou et al. (2002) and Loukas (2002)
5
Literature Review
Land use Change
Land Use
Change
impacts on reservoir operation
Burn and Simonovic (1996), Georgakakos et al. (2004) and
Rani et al. (2008).
impacts on the watershed hydrology
Bosch and Hewlett (1982), Andréassian (2004),
Viney et al. (2008), Shi et al. (2007) and Nejadhashemi (2011)
.
.
.
6
Literature Review
Land use Change
Land Use
Change
impacts on the watershed hydrology
Koch and Cherie (2013), Mango et. al (2011), Gosh and
Misra (2010),Tu (2009), Li et al., (2009), Roosmalen et al.
(2009), Guo et al., (2008), Hundecha and Bárdossy (2004),
Legesse et al., (2003), Barlage et al., (2002) and Lørup et
al., (1998)
7
Case Study
Aharchai River basin and Sattarkhan Dam in Northwestern Iran suffer from these cited problems and issues.
Potable
Aharchai river
Sattarkhan
Reservoir
Agricultural
Environmental
industrial
8
Case Study
 Outlet flow average 2.9m3/s
 average annual temperature 10.7°C
 annual precipitation about 300mm.
 elevations vary between 1420 and 2870 m
 water supply of the reservoir has been deteriorated during
recent years due to excessive water shortage and droughts.
for Example:
1999-2000 and 2000-2001 drought losses and severe damages in Aharchai
River Watershed.
9
Methodology
The research Objectives
 Evaluating the impacts of land use change and climate
change on both hydrologic regimes and water
resources of a River Basin.
 Mitigating the impacts of land use change and climate
change and drouon both hydrologic regimes and water
resourht occurrence on Reservoir operation algorithm
10
Observed rainfall
Methodology
Global Circulation
Model (GCM) outputs
Rainfall prediction scenarios
Statistical downscaling (SDSM) and
ANN (MLP) prediction Model using GCM models outputs
Watershed surface hydrologic data
Hydrologic watershed scale
model
(SWAT)
Watershed land use
observed variations
Ensemble stream flow prediction (ESP) scenarios
Considering observed inflow probablities
Evaluating of planning scenarios
Considering land use and rainfall
Sustainable river basin land use
management
Reservoir operating policies
considering inflow uncertainties based on rainfall
uncertainties and watershed land use dynamics
11
Methodology
1. Predicting future rainfall scenarios and
temperature using GCM and downscaling
models
2. Simulating the watershed hydrology and
reservoir inflow changes based on rainfall and
land use scenarios.
3. Evaluating the land use and climate change
impacts on watershed hydrology
4. presenting reservoir operation algorithm
considering these impacts
12
Methodology
Rainfall prediction
Second hadley centre coupled ocean-atmosphere GCM
(HadCM3) data in two series scenario A2 and B2
(Massah, 2006).
statistical downscaling model (SDSM)
Artificial Neural Network (ANN) model
Temperature prediction
statistical downscaling model (SDSM)
13
Methodology
Statistical Downscaling Methods
ANN
SDSM
Input Layer
Hidden Layer
Output Layer
1
1
1
2
2
2
R
S1
S2
1
1
14
Methodology
SWAT Hydrologic model
SWAT is a semi-distributed daily time step, continuous
simulation model that can be applied at the river basin
scale to simulate the impact of land management
practices on water (Arnold et al., 1998)
parameters in converting rainfall to runoff
climatic parameters: rainfall, temperature,…
local ingredients: land use type, soil type, watershed
area and other basin characteristics,…
15
Methodology
SWAT Hydrologic model
16
Methodology
17
Methodology
Land use change scenarios
The land surface covers effects on flow variation are
investigated for past to now with using land use scenario
maps. The land use maps are prepared with using
satellite imagery that converted to classified map.
Landsat satellite 7 for 1976, 1987 and 2001 years.
18
Methodology
Land use change scenarios
Table.1. The classified distributions of land use scenarios based on satellite images
1976 LA
1987 LB
2001 LC
dry farming
15.7
9.2
17.1
combination of dry farming and range
3.5
6.1
1.3
Range Type 3
27.9
9.2
19.8
Range Type 1
8.6
10.4
7.6
irrigated farming
2.1
0.8
1.2
bared land
6.5
20.7
52.3
combination of irrigated farming and orchard
35.7
43.6
0.3
Lake
--
--
0.4
Land use Type
19
Methodology
Reservoir Operation
Dynamic programming (DP)
Hedging rule operation for drought conditions
(Imen, 2007)
P
t
Hedging Rules
SOP
Dt
α2*Dt
α1*Dt
Region 1
Region 2
Region 3
St
Smin
Sfirm
Starget
Smax
20
Rainfall Prediction SDSM
Error Tolerances
Rainfall Predicted
Model
Scenario
Range
10%
20%
30%
Calibration
34%
49%
70%
Validation
32%
37%
56%
Calibration
34%
40%
50%
Validation
29%
37%
51%
SA
SB
120
Observed
100
Rainfall (mm)
Results
SA
SB
80
60
40
20
0
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Month
21
Results
Temperature
Prediction SDSM
22
Results
Rainfall Prediction ANN
23
Results
Monthly
Reservoir
inflow
Rainfall Prediction
selected Scenarios
Wet
Mean +10%
Long term Mean
Normal
Mean -10%
Dry
Mean -30%
Very Dry
Historical Time Period
Time Period
Normal Scenario
Wet Scenario
2006-2015
MB
SA
2016-2025
SB
SA
2026-2035
MB
MA
2036-2045
MB
SA
2046-2055
SA
MA
24
Results
SWAT Hydrologic model
Calibration and Validation
1998 to 2005
Objective Function Value
Calibration Period
Validation Period
Nash-Sutcliffe (E)
0.7
0.82
0.72
0.83
Determination coefficient
(R2)
Reservoir inflow simulation
2006-2055
25
Results
SWAT Hydrologic model
Model Period
Land use scenarios
Land use
LA Scenario
LB Scenario
LC Scenario
scenario
(1976)
(1976)
(1976)
0.79
0.5
0.64
0.82
0.65
0.82
0.85
0.6
0.8
0.85
0.85
0.95
Nash-Sutcliffe
(E)
Calibration
Determination
coefficient
(R2)
Nash-Sutcliffe
(E)
Validation
Determination
coefficient
(R2)
26
Results
Reservoir operation Using DP
LC (2001)
Land use scenario
LB (1987)
LA (1976)
Very Dry
Dry
Normal
Wet
Very Dry
Dry
Normal
Wet
Very Dry
Dry
Normal
Wet
2006-2015
11.4
26.04
22.8
28.56
6.84
20.64
9.48
24.36
13.8
30
50.4
67.2
2016-2025
12.96
30.6
33.24
39
11.64
43.8
35.64
59.04
17.52
52.8
69.6
85.56
2026-2035
10.92
25.2
19.56
38.64
7.68
25.2
13.44
51
12.12
25.32
43.68
69.24
2036-2045
10.2
30.6
16.2
29.64
6.6
21.84
4.8
31.8
7.44
10.56
36
53.28
2046-2055
12.12
27.36
24.48
41.4
6.6
17.4
14.52
22.8
11.88
34.44
40.32
57.6
Total
11.4
26.04
22.8
28.56
6.84
20.64
9.48
24.36
13.8
30
50.4
67.2
Basin
Time
Period
moisture
state
Dependable Water ***
*** the water criterion that can be released in an apparent
time period regarding to reservoir system and region
limitations.
27
Results
Reservoir operation
Using DP
Dynamic Rule Curve
28
Results
Hedging rule operation
Land use
Scenario
Demand
Time period
Hedging
2 A
1A
2P
1P
coefficients
2006-2015
0.6
0.4
1
0.8
Current
2016-2025
0.6
0.4
1
0.8
Land use
2026-2035
0.6
0.5
0.9
0.7
(LC)
2036-2045
0.6
0.5
1
0.8
2046-2055
0.7
0.6
0.9
0.8
2006-2015
0.8
0.6
1
0.9
Modified
2016-2025
0.8
0.6
1
0.9
Land use
2026-2035
0.7
0.5
1
0.9
(LA)
2036-2045
0.7
0.6
1
0.9
2046-2055
0.6
0.5
1
0.9
29
Conclusion
 Considering three land use scenarios (LA,LB,LC) and four rainfall
prediction (wet, normal, dry and very )scenarios, as a 4 × 3 matrix
exactly 12 surface runoff scenarios may occur for future hydrologic
changes that needs 3 calibrated and validated watershed model.
 The dry, very dry and wet scenarios shows a fluctuated trend in
hydrologic changes and the extreme surface runoff has a falling
trend. The normal scenario is more stable than other scenarios.
 The LA land use scenario is presented as a scenario that should be
reached to mitigate the impacts of climate change. The outputs
for this scenario is compared with current land use scenario (LC)
30
Conclusion
 The dynamic rule curve are presented for four rainfall
scenarios and two land use scenarios (LA, LC) in the next
50 years in long-term (five 10-years step)
 The hedging rule coefficients are determined for very dry
rainfall scenario and two land use scenarios (LA, LC)
 this study shows mitigating the negative impacts of climate
and land use changes on available surface water resources
in order to reach watershed management, the operation
algorithm should consider the land use changes and
climatic conditions simultaneously.
31
Aharchai River
Sttarkhan Dam