Skip to Main content Skip to Navigation
Theses

Analyse des compromis entre la production et l’efficience de l’eau et de l’azote dans les systèmes céréaliers méditerranéens à base de blé dur

Abstract : The low efficiency of non-renewable resources such as water and nitrogen is a constraint for a sustained increase in cereal production. The simultaneous increase in water and nitrogen use efficiency and yields is a major challenge for cereal production in the Mediterranean, mainly for durum wheat production. The aim of the thesis is to analyze the variability of durum yields in Tunisia with respect to the two factors of production water and nitrogen and the opportunities of jointly increasing productivity and efficiency in a durum wheat-based cropping systems. This study is based on experimental data, regional statistics and farm surveys conducted on a sample of 537 agronomic situations (the combination of a farmer’s field, a year and a previous crop) which are representative of the diversity of farmers’ practices in four grain-producing regions that provide a major part of cereal production. Based on the efficiency decomposition approach and the concepts of limiting factor, eco-efficiency frontier and yield gap, data collected allowed us to establish a framework allowing to analyze trade-offs between the resource (water and nitrogen) use efficiency and yield. Tested with experimental data and applied to farmers' data for the case of nitrogen, this framework demonstrated that non-cereal preceding crops, especially legumes, result in a higher potential for N uptake by durum wheat than with a monoculture. Diversified rotations result also to an increase in both yield and N-use efficiency of the following durum wheat. The increase in the efficiency frontier of nitrogen capture is partly of-set by increased N uptake gaps in farmers’ fields indicating the presence of other limiting factors. Water and its interactions with nitrogen could be considered among the main factors that may affect nitrogen uptake and hence yields of durum wheat. This work would allow combining, on the one hand, the diagnosis of limiting factors at the level of farmer’s fields and on the other hand the analysis of scenarios for the management of trade-offs between production efficiency with farmers and decision-makers.
Document type :
Theses
Complete list of metadatas

https://tel.archives-ouvertes.fr/tel-02008155
Contributor : Abes Star :  Contact
Submitted on : Tuesday, February 5, 2019 - 3:33:32 PM
Last modification on : Monday, October 19, 2020 - 2:18:02 PM
Long-term archiving on: : Monday, May 6, 2019 - 4:02:29 PM

File

17-0019_Ben_Zekri.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02008155, version 1

Citation

Yosser Ben Zekri Mghirbi. Analyse des compromis entre la production et l’efficience de l’eau et de l’azote dans les systèmes céréaliers méditerranéens à base de blé dur. Sciences agricoles. Montpellier SupAgro, 2017. Français. ⟨NNT : 2017NSAM0019⟩. ⟨tel-02008155⟩

Share

Metrics

Record views

161

Files downloads

1969