Diapositiva 1

1
Evidences of changes in rainfall caused by
deforestation
Conceptual models of deforestation impact on
precipitation - Avissar et al., 2002
Carey et al 2001
2
Soil erosion and water regulation
3
Fire-sensitive ecosystem Old agricultural
terraces colonised by pine forest
Unburned Very low sediment yield, rainfall
amount dependent Burned High sediment yield was
plant cover dependent. Degradative dynamics
changed from 50 cover.
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DESERTIFICATION
Drought
Loss of plant cover, soil water infiltration and
soil moisture


Land degradation
Soil erosion


Increased water scarcity
Improvement of water availability is necessary
to restore desertified lands
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STRATEGIES FOR POST-FIRE DEGRADED LAND
REHABILITATION
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PLANTATIONS (1992)
Pinus halepensis
Quercus ilex ssp ballota
100
100
90
90
80
80
70
70
60
60
Survival
50
50
40
40
30
30
20
20
10
10
0
0
Marls
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THE DROUGHT
100
80
60
MORTALITY
40
20
0
160
140
120
100
80
60
40
20
LENGTH OF DRY PERIOD
Pinus halepensis
Quercus coccifera
Quercus ilex ssp. ballota
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Improving plant survival
11
The role of diversity
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OPTIONS .

• Species diversification, ecotypes, genotypes,
  manipulating species plasticity
• Micro-habitat conditioners
• Soil preparation and amendment (threshold limit
  for most woody species in our drylands 40 cm
  soil depth)
• managing plant-plant interactions

• In order to
• Overcome transplanting shock
• Survive dry spells
• Grow during wet spells

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PLANT QUALITY
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Quercus species
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