AGRICULTURAL WATER MANAGEMENT PRACTICES IN MENA REGION FACING CLIMATIC CHALLENGES AND WATER SCARCITY

Abstract

Location of Tunisia between the Mediterranean and the Sahara, is an arid country on a major part of its territory. This aridity combined with variability Mediterranean climate makes water a resource both scarce and irregularly distributed in time and space. Tunisia is classified by international organizations as being among the least endowed with groundwater resources countries in the Mediterranean basin. To improve modernization policy in the agriculture sector in Tunisia, essential factors for saving water and for a sustainable development must be followed as providing farmers with the technology they need to maximize the efficiency and rational use of water to optimize the use of water in agriculture. The subsurface irrigation has several advantages in terms of saving the amount of water in a sustainable development that aims to protection of groundwater. The aim of the contrasting water management techniques described in this paper is to minimize spatio-temporal losses. Subsurface irrigation can increase stores water in the root zone, allows limiting losses by evaporation and percolation. It also helps reduce weed growth. Then, we have carried out studies on the following irrigation systems: subsurface drip irrigation system (SDI) and Buried diffusers (BD). The studies consisted of monitoring the water saving of each of these techniques as well as their effects on the profitability of different crops. For example, SDI was used for two treatments full irrigation (T1) and deficit irrigation with 50% of crop Evapotranspiration (T2). Soil water content (SWC) variation was more important at the end of the season due to root uptake and hard climatic condition, treatment T2 had less water stock and best water use efficiency with 10.83 kg/ha than 5.85 kg/ha for T1. While the average values of the SWC are 19.6 ± 2.68; 15 ± 3.81 and 14 ± 3.72% respectively for buried diffuser with full irrigation TD100, deficit irrigation with 50 TD50 and deficit irrigation with 25% TD25.