Evoluting Law And Calculating Analyse Of Land Use System In Handan City

This thesis reports the results of a systematic analysis of the distribution of major nutrients in different land use systems in Handan, Hebei Province, China. This analysis was based on data collected in soil surveys conducted in 1980,1993 and 2003; data from environmental monitoring over many years; and data from specific investigations using GIS and GPS.The mix of land use in Handan has changed significantly, with arable and herbage land areas decreasing, and residential, mining, transport, forest, fallow and gardon land areas increasing.The soil organic matter content and total nitrogen in the land use systems are high in the western part and low in eastern part of Handan, and are showing an increasing trend from 1980 to 2003. The content of alkali-hydrolyzable nitrogen fluctuated without showing obvious trends.The total soil phosphorus varied depending on the parent material prior to the 1980s, but has since been strongly influenced by cultivation and management practices over the past 23 years. Rapidly available phosphorus has also changed both spatially and temporarily as a result of land use activities, tending towards similar levels.Total soil potassium was high prior to the 1980's and was closely related to parent material. The spatial distribution has changed reflecting land use activities between 1980 and 2003. Rapidly available potassium decreased significantly from 1980 to 1993, and fluctuated from 1993 to 2003. The use of chemical potassium fertilizer and straw incorporation can prevent this decline.The main environmental concern is the increase of total hardness of water. The quality of groundwater is good and suitable for drinking and irrigation in the west and southwest of Handan. However, the groundwater has been polluted to various degrees by sulphate, cations, nitrate, and are not suitable for drinking in central part of Handan. The east part of Handan is the worst polluted, where the water quality has reached the types of â…£~â…¤ with the main pollutants being nitrate, sulphate, total hardness, chloride, fluoride. The pollution becomes worse closer to the river. Fuyang river is increasingly polluted, but there is no obvious trend in Zhanghe river, Weihe river, Yuecheng reservoir, and Dongwushi reservoir. Overall, the environmental quality is good in Quzhou county, which is located in the east part of Handan. The most single and complicating index of pollution do not exceed 0.7, but in a few places they are 0.7