Several systematic surveys were carried out on the water resources, ecological changes
and water use situation in the Shiyang River basin during 1984–2001. The surveys
included the investigation and recording of annual rainfall, river inflow and water
consumption in all the parts concerned, the changes in available water resources in the
lower reaches, the annual irrigated acreages and irrigation schedules, water use efficiency
for the canal systems, the planted acreages for different crops, the tillage and
cultivating measures, crop yield, the change of water consumption under the watersaving
irrigation, water consumption of different crops, the changes in groundwater
tables and quality, the growth conditions of desert plants and ecological groundwater
tables in the region