LAUSR

Abstract The objective of this work is to determine the effects of climate change on the water needs of crops in the Bounamoussa perimeter, which is one of the large irrigation systems in the North-East of Algeria in order to predict a diagnosis of its operation. This region covers an area of 16,500 ha and is specialized in vegetable production. The climatic trend of recent years in the study area is characterized by increasingly severe drought conditions that have compromised agricultural production at this perimeter. In this study, the results of the climatic parameters projected to 2050 and 2080 under the Climate Wizard program were used in the CropWat 8.0 program for estimating the future water requirements of crops, taking into account the three Scenarios (B1, A1B, A2) of greenhouse gases (GHGs). The Decision Support System for Agrotechnology Transfer (DSSAT) 4.5 program has also been used to generate future climatic parameters (temperatures and rains) to be compared with those of the climate wizard. The results obtained in 2050 and 2080 show a trend towards increasing temperatures and a fall in rainfall for all models and that the water requirements will be multiplied by 3 to 5 times the current needs. This situation will cause an imbalance in the operation of perimeter irrigation systems. Among the measures of adaptation to this situation in the first place is the change of the date of planting after calibration of the two models for all the cultures of the perimeter.