Title: Optimization of Chahbani Buried diffuser installation for Jemna oasis suistanibility (North Africa)
Abstract:
In arid areas, the irrational irrigation with brakish water could have a negative impact not only in economic terms, but also in terms of global health and environmental damage. Micro irrigation appears to be a guarantee of economic, environmental and social sustainability in many irrigated areas in the world. However, inadequate design of this irrigation system reduce the water efficiency and in some cases lead to soil salinization.In this context, an assessment of an innovative subsurface irrigation system was conducted in Saharan Tunisian Jemna oasis to determin its optimum installation design regarding soil salinization and crop yield. Field investigations were conducted during two crop years (2018, 2019). Dielectric sensors were installed at six soil depths until 1.20 m for soil water moisture (θ) and pore electrical conductivity (ECp) real time monitoring. The HYDRUS (2D/3D) numerical model was calibrated then applied to investigate four different buried diffuser optimization (opt) positions from the trunk of the palm tree (X) and soil depths (Z) on root water uptake, relative yield production (Yr) and soil salinity distribution. According to buried diffuser position scenarios, installation of the buried diffuser at the canopy of the date palm T1opt (X=1.5 m) as used in the region, showed the least Yr (37%). However, for the same lateral distance, X=0.5m, the Yr was equal to 54 % and 71%, for T2Opt (Z=0.3 m) and T4Opt (Z=0.6 m), respectively. According to simulation results, all position scenarios showed salt accumulation on the top soil layers and supplemental leaching using surface irrigation is thus recommended.
Biography:
Nesrine Zemni is a Hydraulic engineer graduated from the National Agronomic Institute of Tunis (INAT), 2013. She holds a master in modelling in hydraulics and the environment from National Engineers School of Tunis (ENIT), 2015. She obtained her PhD in hydraulic engineering from ENIT. Her research fields are numerical modelling of water flow and solute transport in porous media, soil salinity, smart irrigation, TDR and FDR technique.
