cn 3 th14_eeza_slm_measures_in_spain_sole_benet
TRANSCRIPT
Sustainable land management measures in semiarid SE Spain:
the Alagüeces farm (Murcia)
Albert Solé-Benet1, Joris de Vente1, Ashraf Afana1, Jorge López1, Carolina Boix-Fayos2
1 EEZA-CSIC (Almería) 2 CEBAS-CSIC (Murcia)
Los Alagüeces Zarzadilla de Totana LorcaMurciaSpain
Land uses: rangeland, dryland cereals, almonds
Desertification indicators in the area:
- Soil erosion (rills, gullies)
- Water scarcity, droughts
- SLM 1: Green manure
Autumn 2008
Spring 2009)
SLM technologies under test
- SLM 2: reduced tillage in almonds
Reduced tillage = disks + cultivator (2 operations per year)
Conventional tillage = disks + cultivator (3 - 5 operations)
- SLM 3: boquera
= diversion from main channel (water harvesting system)
- SLM 4: mulch
Mulch used: cereal straw
- SLM 5: reduced tillage in cereals
Mouldboard ploughing
Field A (almonds without terraces)
3 subplots, 3 replicates: - green manure (AL1-AL2-AL3),- rreduced tillage (AL4-AL5-AL6),- control (AL7-AL8-AL9).
Implementation plan
Variables monitored: - runoff- sediment yield- almond yield- organic carbon sequestration.
Implementation plan
- Gerlach troughs for runoff and sediment yield monitoring in field A and B
Field B (almonds in terraces): - water harvesting (boquera)- mulch.- control.
Variables monitored:- water height from boquera (capacitive
sensor) runoff rates
− θ at 30-35 cm continuously (4 probes /
SLM technique & control)- θ manually after events at 0-20 cm- almond yield.
Implementation plan
Field C (cereals in 2 subplots, 3 replicates): - control (conventional tillage): CE1-CE2-CE3- reduced tillage: CE4-CE5-CE6.
Variables monitored: - runoff- sediment yield- cereal yield.
Implementation plan
© Joris de Vente
Implementation plan
- Meteorological station
Variables measured:P, T & humidity air, wind direction & velocity
- Sediment data: we need to know the contribution area to every Gerlach trough
© Joris de Vente
Preliminary results
Drainage accumulation flow at 5 cm resolution generated by the D8 method using IDRISI
3D representation of field site A. DEM generated by ANUDEM at 5 cm resolution. Original data from terrestrial laser scanner Leica ScanStation 2
- First sediment data
© Joris de Vente
Preliminary results
Sediment yield in 1 year in site C(cereals)
0
1
2
3
4
5
6
control reduced tillage
sedi
men
t yi
eld
(kg)
Sediment yield in 1 year in site A (almonds)
0
5
10
15
20
25
green manure reducedtillage
control
sedi
men
t yi
eld
(g/m
²)
Field B - average soil water content in 3 SLM systems
0
5
10
15
20
25
30
35
40
45
18-
11-
08
18-
12-
08
17-
01-
09
16-
02-
09
18-
03-
09
17-
04-
09
17-
05-
09
16-
06-
09
16-
07-
09
15-
08-
09
14-
09-
09
14-
10-
09
13-
11-
09
13-
12-
09
12-
01-
10
11-
02-
10
13-
03-
10
12-
04-
10
12-
05-
10
11-
06-
10
11-
07-
10
10
-08
-10
09-
09-
10
So
il w
ater
con
ten
t (%
vol
)
Control
Water harvesting
Mulch
0
5
10
15
20
25
30
35
40
45
18-1
1-08
18-1
2-08
17-0
1-09
16-0
2-09
18-0
3-09
17-0
4-09
17-0
5-09
16-0
6-09
16-0
7-09
15-0
8-09
14-0
9-09
14-1
0-09
13-1
1-09
13-1
2-09
12-0
1-10
11-0
2-10
13-0
3-10
12-0
4-10
12-0
5-10
11-0
6-10
11-0
7-10
10-0
8-10
09-0
9-10
So
il w
ater
con
ten
t (%
vol
)
Control
Water harvesting
Mulch
Field B - maximum soil water content values in 3 SLM systems
- Soil moisture
Preliminary results
Preliminary results
- Almond yields
Almonds yield in site A
-1
1
3
5
7
9
11
13
15
Green manure Reduced tillage Control
annu
al y
ield
(kg
/ tr
ee)
Almonds yield in site B
-1
1
3
5
7
9
11
13
15
Boquera Mulch Controlan
nu
al y
ield
(kg
/ tr
ee)
Preliminary results
Magnitude and intensity during runoff events
0
10
20
30
40
50
60
70
80
90
100
21/0
9/09
30/0
9/09
16/1
2/09
12/0
1/10
02/0
2/10
24/0
2/10
21/0
4/10
04/0
6/10
18/06
/10
25/0
8/10
P (
mm
) &
Inte
nsity
(m
m(h
) P P intensity
- weather Daily Precipitatipon and Average Daily Temperature
'Los Alhagüeces'
0
5
10
15
20
25
30
22/0
8/20
08
05/0
9/20
08
19/0
9/20
08
03/1
0/20
08
17/1
0/20
08
31/1
0/20
08
14/1
1/20
08
28/1
1/20
08
12/1
2/20
08
26/1
2/20
08
09/0
1/20
09
23/0
1/20
09
06/0
2/20
09
20/0
2/20
09
06/0
3/20
09
20/0
3/20
09
03/0
4/20
09
17/0
4/20
09
01/0
5/20
09
15/0
5/20
09
29/0
5/20
09
12/0
6/20
09
26/0
6/20
09
10/0
7/20
09
24/0
7/20
09
07/0
8/20
09
21/0
8/20
09
Pre
cip
itat
ion
(m
m)
0
5
10
15
20
25
30
35
Tem
per
atu
re (
ºC)
Conclusions (to be considered with caution)
- Water harvesting increases soil water content and consequently almond yield. - Clear results on sediment yield depend essentially on contribution areas which calculations are not straightforward from laser scanner data. Consequently final results on sediment yield might change with regards preliminary ones.
- Mulch has not produced positive results so far. Possible causes: technology not properly implemented and/or mulch type (cereal straw). Is this mulching type affecting infiltration negatively causing lower soil water content?
- Green manure has had a positive influence in almond yield with regard reduced and conventional tillage and seem to reduce soil and water loss.
- Results from field C (cereals) are still under process.