Transcript Strategic Approaches to Integrated Management of Land

Regional Knowledge Exchange on Decision-support Tools and Models to Project Improved Strategies for Integrated
Management of Land, Water and Livelihoods
22-27 September, 2013, Djerba, Tunisia
Strategic Approaches to Integrated Management of Land,
Water and Livelihoods along an Aridity Gradient:
Southern Tunisia site
Team
Biophysical
Socio-Economic
H. Khatteli
M. Sghaier
M. Ouessar
M. Abdeladhim
K. Nagaz
R. Bechir
M. Ben Zaied
A. Zerrim
F. El Mokh
A. Hachani
Study sites in Tunisia
S1
S1 (North): Tunis (semi arid)
S2 (Centre): Sidi Bouzid/Kasserine (semi
arid)
S2
S3 (South) : Medenine/Tataouine (arid)
S3
Wadi Hallouf/Oum Zessar watersheds, Medenine
•Transect stretching from Plateau of Dhahar to the Gulf of Gabès
(Mediterranean sea): 3 main basins: wadis of Hallouf, Oum Oum
Zessar, Oum Ettamr).
• Area: around 1500 km2.
• Rainfall ranges between 160 mm (east, plain of Jeffara) , 200
mm (central part, mountain of Beli Khedache) and less than 100
mm (west, plateau of Dhahar).
• Land use: East: olives, small scale irrigation; Central: fruit trees
behind water harvesting structures; West: rangelands.
• Population: around 50000 inhabitants
MODELLING OLIVE GROVES
VULNERABILITY
TO CC
climatic data: Baseline period,
until 2030 and until 2090
collecting data
Soil map
Land use
map
Treatement
Images
Landsat 5 and
7
Geométric and
atmospheric
correction
NDVI
HidroMORE
Conceptuel Model
9
Slightly suitable Moderately suitable
suitable
Baseline period
28%
46%
26%
Horizon 2030
19%
68%
13%
Horizon 2090
24%
76%
0
41
GABION CHECK DAMS EFFICIENCY
WATER MANAGEMENT IN THE
IRRIGATED AREA
Actions
1- Evaluation of on-farm irrigation scheduling of drip irrigated vegetable crops
under arid conditions of Tunisia
2- Deficit irrigation of orchards : case study of citrus trees
Location
- Bedoui & Megarine in the arid part (R: 150 mm & ETo: 1500 mm)
Pilot site: Evaluation of on-farm irrigation scheduling of drip irrigated
vegetable crops under arid conditions of Tunisia.
- Water source: private shallow well having an ECi of about 5.8 dS/m, flow rate
ranging between 3-4 l/s and a depth less than 35 m
- Soil: Sandy soil texture (Clay: 6.77%, Loam: 12.68% & Sand: 80.55%) having low
organic manure (<0.8%)
- Vegetable crops: potato, carrot, green bean and pepper
- Irrigation system: Drip irrigation method
Irrigation scheduling methods
Two irrigation treatments based on the use SWB to estimate irrigation amounts and
timing were compared to traditional farmer practice.
Field monitoring
• Soil salinity and water content
• Ground canopy cover, stomatal conductance
• Yield and its components at physiological maturity
• Water supplies (I+R) (using water meter and rain gauge)
• Water productivity (WP)
WP (kg/m3) = Yield (kg/ha) / irrigation water (m3/ha)
Results
First year of experiment
Data collected on Potato, carrot & green
bean,
Pepper experiment is still in progress
7
6
ECe (dS/m)
5
4
3
7
2
6
FM
DI70
SWB100
5
1
Potato
0
Initiale
4
15/11/2012
01/01/2013
23/01/2013
Date
3
7
2
6
1
FM
DI70
SWB100
Carrot
5
0
Initiale
05/11/2012
05/12/2012
Date
05/01/2013
19/02/2013
ECe (dS/m)
ECe (dS/m)
FM
DI70
SWB100
4
3
2
1
Green bean
0
Initiale
08/11/2012
27/11/2012
12/12/2012
Date
15/01/2013
03/02/2013
30
Yield
LSD (5% )
Carrot, 3.627
Potato, 3,224
Green bean Luz, 4.698
Geen bean L, 4.749
14%
25
24%
23%
7%
37%
7%
20%
18%
15
10
5
Potato
Carrot
Green bean (Luz di
otono)
Treatments
FM
DI70
SWB100
FM
DI70
SWB100
FM
DI70
SWB100
FM
DI70
0
SWB100
Yield (t/ha)
20
Green bean (Local)
Water applied
600
18%
400
14%
12,5%
300
30%
200
100
Potato
Carrot
Treatments
Green bean
FM
DI70
SWB100
FM
DI70
SWB100
FM
DI70
0
SWB100
Irrigation supply (mm)
500
Water productivity
12
FM WP
Carrot, 35%
Potato, 44%
Green bean, 28%
DI WP
Carrot, 22%
Potato, 9.9%
Green bean, 32%
10
LSD (5% )
Carrot, 1.578
Potato, 1.797
Green bean Luz, 2.002
Geen bean L, 2.037
6
4
2
Potato
Carrot
Green bean (Luz di
otono)
Treatments
FM
DI70
SWB100
FM
DI70
SWB100
FM
DI70
SWB100
FM
DI70
0
SWB100
WP (kg/m3)
8
Green bean (Local)
• Pilot site Megarine:
Irrigated field (55ha) with relatively fresh water (1-1.5 g/l) from a tube well.
Pilot site serve testing technical itinerary for fruit trees
Field experiments on improved water productivity by deficit irrigation and irrigation
scheduling: Implications for saving water in citrus orchards
Experiments in a drip irrigated citrus orchards are actually launched in the zone of
Megarine, Médenine. (12 years-old ‘Meski Maltaise trees grafted on Bigaradier with tree
spacing of 7x6 m)
Four drip emitters per tree (4 l/h) connected to a double drip line, two per side of the
tree, are used in the experiment
Pilot site: Improved water productivity by deficit irrigation and irrigation
scheduling: Implications for saving water in citrus orchards
Irrigation treatments
- Control treatment (FI-100) irrigated at 100% of
- The DI treatments irrigtaed at 75 and 50% of ET (DI-75, DI-50)
- FM irrigated according to farmer irrigation practice
FM, DI & FI implemented during the active period of citrus corresponding to different
phenological stages (flowering and initial fruit set, fruit growth, and maturity) and postharvest
For citrus experiment
Irrigation strategies will be evaluated according to their impact on:
- amount of irrigation water saving
- vegetative growth (diameter fruits)
- stomatal conductance
- yield, fruit size, total soluble solids (°Brix)
- water productivity
- soil salinity
MPDELLING CLIMATE CHANGE
IMPACT AND ADAPTATION
STRATEGY ASSESSMENT ON CROP
PRODUCTION
- Selected crop : potato
- Model selection: Aqacrop
- Meteorological data
Médenine station
Climate scenarios
Minimum and maximum temperature and rainfall projections will be used as input for t
the AquaCrop model and to estimate the future ETo using the FAO tool EToCalculator.
- Modelling the impact of climate change on crop yield
- Calibration and Validation of AquaCrop for Potato
• Field experiments (2001-2004) in Médenine region
• Calibration and validation of the model
• Collection of weather data, soil characteristics and management inputs
• Calibration on basis of observed soil water content, biomass, yield and canopy cover
• Calibration by adjusting the crop input file
Model validation is in progress
- Model simulation
After model calibration and validation, the model will be used to determine the impact of
climate change through simulation of biomass and yields over periods.
- Modelling the impact of climate change on crop yield
Input data for AquaCrop obtained from the mean minimum and maximum air
temperatures and total rainfall data from the downscaled GCM data sets, and reference
evapotranspiration values).
The AquaCrop model to predict potato yields under the following conditions:
• Current situation (simulate actual yields) (2000-2010)
• Impact (2010-2100): Projected climate for three time periods of ten years: 2020-2030,
2050 - 2060 and 2090-2100 (simulate yields under climate change scenarios)
• Adaptation scenarios (2010-2100): Projected climate using recommended adaptation
strategy i.e. DI/SI using the AquaCrop model
AGRO-SOCIO-ECONOMICS
Activity 4: Livelihood and quantification of benefits in terms
of enhanced benefit/cost ratio
Household survey and data collection
139 Household’s surveys have been finalized in the study area. The aims of these
technico-socio-economic surveys are to provide data for the three activities;
Since the study site is a Watershed, the sample of the interviewed households
was homogeneously distributed from up-stream to the down-stream area.
The technico-socio-economic data-base is being under construction :
Household Characteristics ;
• Livelihood strategy (Human Assets , Natural Assets, Physical assets (farm capital),
Financial assets (farmer’s income and expenditure), Social assets);
• Farming system characteristics and Land resources ;
• Water harvesting techniques ;
• Resources bases (sources of water for agriculture).
Activity 4: Livelihood and quantification of benefits in terms of
enhanced benefit/cost ratio
104 complementary technico-socio economic surveys have
been finalized in the study area (June-September 2013) :
• 74 surveys in the upstream and piedmont and 30 in the downstream
area)
• The aims of these technico-socio-economic surveys are to calculate
WLI indicators : Agricultural land (cultivated area and area under
improved practices, gross margin per ha for target crops, on farm
income, household income. The On-farm income and the Gross Margin
Per Hectare will be calculated using the WLI approach.
Activity 4: Livelihood and quantification of benefits in terms of
enhanced benefit/cost ratio
Calculation and analysis of two type set of indicators:
• Indicators previously identified by WLI Tunisia team identified under the
Sustainable Livelihoods Framework, (five types of asset: human capital, social
capital, natural capital, physical capital, and financial capital);
• Most of the WLI 2012 indicators : Agricultural land (cultivated area and area
under improved practices, gross margin per ha for target crops, on farm income,
household income. The On-farm income and the Gross Margin Per Hectare will be
calculated using the WLI approach.
In parallel, there was also the collection of secondary data from
technical services and regional statistics in order to characterize
gross income (margin) per hectare for dominant crops (olives, figs,
cereals, legumes etc.) and on other indicators in SLF in the
watershed of Oum Zessar.
Economic assessment of climate change effects on agro-ecosystems
Starting of review of available methodologies and
assessment frameworks and consultation of colleagues
concerning water-related agroecosystem services to be
quantified,
Organization of a stakeholder’s workshop (13-14 June,
2013) in order to start discussion about scenarios (local
development scenarios and climate scenarios) to be
presented for discussion during the next Multi-stakeholders
workshop (decision makers, scientists and actors).
Thany you