Abstract form

Diagnosis and control of salinity and nitrate pollution in
Mediterranean irrigated agriculture. The case of Beni Amir (TADLA –
Morocco)
Mouanis LAHLOU*, Brahim SOUDI
Institute of Agronomy and Veterinary Hassan II. Morocco
Agricultural productivity may be constrained by limited water resources and soil and
water quality degradation. In Moroccan conditions, the main degradation processes
occurring under intensive cultivation in the irrigation schemes are: (i) soil salinization,
and alkalinization, soil compaction and (“on-site” impacts) and increased salt and
nitrate loads in irrigation return flows (IRF) (“off-site” impacts) and groundwater nitrate
pollution. A subsequent revision of agricultural practices should be established and an
Integrated Agro – Environmental Management of these constrains is essential.
In order to reinforce scientific, technical and socio-economic investigations and findings
on salt and nitrogen contamination and on pollution control measures in Mediterranean
irrigated agriculture, seven research partners and ten stakeholders in six countries have
collaborated during four years (2006-2009) in the framework of a project called
“QUALIWATER: Diagnosis and Control of Salinity and Nitrate Pollution in
Mediterranean Irrigated Agriculture INCO-CT-2005-015031”.
In Morocco the Academic institutions are represented by the “Institute of Agronomy
and Veterinary Medicine Hassan II”, and stakeholder by the “Regional Office of
Agricultural Development-Tadla” where hydraulic unit covering 2600 ha was selected
as study area. The result of the two hydrological years 2007 and 2008 show that the
District Irrigation Efficiency was about 56% and 52% respectively in 2007 and 2008;
the Water Use Efficiency is about 60% and 59% respectively in 2007 and 2008; the
mass of salts that percolate to the water table (Mg/ha) is about 5.3 and 4.8 respectively
in 2007 and 2008; and the mass of NO 3 -N that percolate to the water table (Kg/ha) is
about 137 and 117 respectively in 2007 and 2008.
In addition a simulation studies has been carried using a set of calibrated and validated
water, salt and nitrogen models to analyze the effectiveness of best management
alternatives for off-site pollution control.
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