Assessment of blue and green agricultural water footprint in the Gaza Strip, Palestine.

The water system in the Gaza Strip is deteriorating as the agricultural sector consumes more than 50% of the available water. There is an urgent need for effective tools that rationalize agricultural water consumption. The concept of the blue and green water footprint (WF) was applied to determine the actual water consumption of all crops in the Gaza Strip and evaluate the sustainability of the agricultural water footprint. The CROPWAT 8.0 model was used to calculate the crop water requirements (CWR) and estimate evapotranspiration (ET) according to the Hoekstra manual. The results show that the blue water footprint of crops was 82.15 mm3 distributed among 59.4 mm3 of horticulture trees, 3.65 mm3 of field crops, and 19.2 mm3 of vegetables whereas the green water footprint was 33.82 mm3. The main insight is that the water footprint's sustainability reflects a serious indicator of the depletion of blue water in the Gaza Strip and if WF is applied, 40 mm3 of water can be saved annually, which constitutes 33% less than the current usage. It is promising to use the water footprint concept as a distinct tool in supporting the decision-maker to reduce water consumption and enhance water resource sustainability.