Methodology

In plain arid areas, a water-balance method can be applied to evaluate groundwater resources through calculation of stream channel infiltration, canal infiltration, field infiltration, precipitation infiltration and lateral runoff. (Zhu et al., 2004). A methodology is presented to quantify discharge and recharge of groundwater system according to land use types. The result of the methodology will give the quantity of recharge and discharge and therefore understand human dominated eco-hydrological system in arid irrigation area. According to the characteristics of groundwater system in the study area, a reasonable assumption that irrigation area is recharge area and everywhere without surface water supply is discharge area is made through out the research. The methodology consists of the following components: (a) delineation of river and groundwater interaction based on long-term surface water observation and recent water table surveys; (b) setting up a groundwater model and estimating groundwater recharge, discharge and the groundwater flow between the recharge and discharge area; (c) estimating salt exchange through groundwater system.