Impact of Agricultural Practices on Soil Nitrate Accumulation in the Jordan Valley: The Urgent Need for Soil Nitrogen Management Planning

The effect of agricultural practices on nitrate accumulation in soils of different farmland systems in the Jordan Valley (JV) is not yet documented. This study aims at quantifying nitrate concentrations in top-soil and investigating its spatial distribution in the JV in order to help developing a nitrogen management plan for the JV. Results showed that nitrate concentrations range from 88.2 to 705.7 mg NO l with an average of 374.4 3 1 mg NO l of copper sulfate extracted top-soils. Nitrate levels erratically increase along the North-South 3 1 transect of the JV with high nitrate levels found in the central and southern parts of the valley. Elevated soil nitrate concentrations are mainly caused by high amounts of nitrate added along with the irrigation water and nitrogen over-fertilization. Results provide the foundation for assessing the soil’s ability to supply plant-available nitrogen and establish field-specific nitrogen recommendations to avoid economic losses and potential human health risk.