The Research Of Ground Water Types And Nitride Distribution In Hohhot-baotou Eastern Sub-basins

Groundwater is the economic, social and environmental indispensable valuable resource.Once contaminated, it will be difficult to recover. Hohhot is the capital of Inner Mongolia Autonomous Region, belongs to arid and semi-arid area,therefore groundwater resources are increasingly scarce.Regulations for protection of groundwater has caused a lot of attentions of the governments at various levels and various functional departments.This thesis is a combination problems of practical work. Hohhot groundwater monitoring data in recent years were statistically analyzed, then making sure the study area.It is given priority to throughout the Tuoketuo county, expanding to the south of Tumotezuoqi and west of Helingeer county, of which the area is approximately2000km2,the area is called Hohhot-Baotou sub-basins.It found that the southeast area is groundwater recharge area, through the study of hydrogeology survey and hydrogeochemical characteristics.Mmeanwhile, the northwest of the study area is runoff area and its groundwater flow speed. As well as,the groundwater environment is in oxidation where nitrification easily occurred. Groundwater flows from the surface to underground with which ammonium nitrogen(NH+4-N) can be oxidized into the nitrate (NO-2-N), nitrate(NO-3-N).Heihe river area is the retention discharge area of groundwater,which various kinds of organic matter and reducing matter is in. So nitrification occurred not easily.Furthermore,the nitrate(NO-2-N), nitrate (NO-3-N)content is higher in recharge area,while ammonium nitrogen (NH+4-N content is relatively high in the retention discharge area.The top has a good impermeable layer.Confined water depth is deeper in the study area,then a nitride water quality is good.However, the contaminated trend has occurred. Because unconfined water depth is shallow, groundwater has been contaminated by nitrogen. The reason for the nitrogen pollution is the natural factors, but mainly is man-made factor which including unreasonable science of livestock and poultry breeding, agricultural and industrial production. Thus the prevention of pollution of groundwater should be paid close attention.