Abhatoo - Centre Nationale de Documentation

CHAPTER I. General Introduction
1. General background
1.1 Why do we need other agronomic strategies?
1.2 How can food insufficiency be reduced? What are the possibilities?
1.3 What is agroforestry? What are the agroforestry systems?
2. Agroforestry an opportunity for sustainable intensification?
2.1 What are the expected benefits of agroforestry?
2.2 What are the challenges of agroforestry today?
3. Tree-crop interactions in agroforestry

3.1 What are the possible relationships in the tree-crop combination?
3.2 Light sharing: from negative to a positive key role
3.3 Water sharing: competition vs. complementarity
4. Does the Stress Gradient Hypothesis hold to agroforestry system interactions?
4.1 How do plant-plant interactions vary according to the stress gradient hypothesis?
4.2 Can the stress gradient hypothesis be considered differently?
4.3 Can negative interactions be reduced by monitoring cultural practices.?
5. Objectives and study hypotheses:
6. Organization of the manuscript:
CHAPTER II General Methodology
1. General approach
2. Study sites
2.1. Study sites: the survey approach
2.2. Study sites: the experimental approach
3. Target species
4. Overview of the different data sets

5. Statistical analysis
CHAPTER III. How does the intercropped barley performance vary along an aridity gradient?
Assessment of olive-barley interactions in response to pedoclimatic factors and smallholder
practices in northern Morocco
1. Introduction
2. Materials and methods
2.1 Study site
2.2 Aridity gradient
2.3 Field data collection
2.4 Soil sampling
2.5 Crop sampling
2.6 Statistical analysis:
3. Results
3.1 Description of agrosystems and farming practices
3.2 The response of barley production to aridity and farming practices
4. Discussion
4.1 Olive trees reduce barley productivity, but promote more stable yields along the aridity gradient.
Conclusion
CHAPTER IV. Olive agroforestry can improve land productivity even under low water
availability in the South Mediterranean
1. Introduction
2. Material and methods
2.1 Experimental site
2.2 Experimental layout
2.3 Water regimes
2.4 Field measurements and sampling

2.5 Crop quality
2.6 Data analysis
3. Results

3.1 Dry matter production at flowering

3.2 Crop yields and yield components
3.3 Crop quality and protein yield
3.4 Olive yield
3.5 Land equivalent ratio (LER)
4. Discussion
4.1 The shade of olive trees reduces crop yields whatever the water regime
4.2 Olive trees limit crop growth and reduce the number of grains per unit area
4.3 Olive trees improve grain filling and grain quality
4.4 Overall, olive agroforestry is more productive than sole crops and trees
Conclusion
CHAPTER V. Dynamic analysis of water flows in a wheat-olive system using the Biswat
model
1. Introduction :
2. Materials & Methods
2.1 BIS-Wat model description
2.2 Data collection for modelling
3. Results
3.1 Effect of intercropping on measured soil water distribution
3.2 Evaluation of Biswat model with measurements
3.3 Simulated water balance components
4. Discussion
4.1 Evaluation of tree-crop water uptake:
4.2 Performance of Biswat Model:
Conclusion:
CHAPTER VI. Discussion
1. Main result summary

2. Methodological limits of this work:
2.1 Limitations related to water gradient: in the surveys
2.2 Experimental limitations
3. Trees limit understory crop performance and enhance system performance
4. The stress gradient hypothesis is not appropriate for agroforestry systems
5. Perspectives