Research On Content Distribution And Change Characteristics Of Cd And Ni In The Farmland In Shenyang Suburb

With the development of urbanization and industrial, the pollution of heavy metal is more and more dangerous. In the process of urbanization, human activities have a profound impact on the environment. The heavy metal content of urban soil is influenced by human activities, such as industrial activities, garbage disposal, transportation and agricultural activities, etc., in addition to the natural factors. The heavy metals in the soil are covered and non degradable, it would lead to the degradation of soil physical properties and the decrease of land use efficiency, Its hazards can not be ignored.Use Shenyang Suburb Farmland Soil as the research object, from Shenyang different administrative region (Shenbei New District, Shenhe District, Heping District, Hunnan District, Tiexi District) were cultivated soil samples were collected, Content, pH, organic matter of heavy metal Cd in cultivated soil were detected and analyzed to investigate the distribution of heavy metals in urban soils of Shenyang city and its pollution. Using the method of statistics, Study The pollution status of heavy metals in soils of Shenyang city and the effect of pH and organic matter content on exchangeable Cd content in cultivated land.The main conclusions are:1. Mostly study areas in the 5 District farmland of outskirts of a city soil pH in the acidic to neutral range, in which the proportion of acidic soil maximum,55.4%.2. Relates to the study of Shenyang in the 5 District farmland of outskirts of a city soil there are different levels of cadmium pollution, the pollution degree from high to low is Hunnan District> Heping District> Shenhe District> Shen north to Shenbei District> Tiexi District, the biggest pollution ratio reached 26.68 times and compared to previous years to survey area of Cd pollution present increasingly deepening trend.3. This study deals with the Shenyang of arable soil in 5 District general did not appear obvious nickel pollution, five area Ni average value were less than the state of Ni background values, but with respect to the content of Ni in the 2006 survey data of cultivated land showed a small increase in, so we for possible contamination still can’t ignore.4. Through the analysis of cadmium pollution cumulative rate can be found that the pollution has more rapid growth trend. Through the soil investigation and classification according to the sampling location and characteristics of the pollution source pollution characteristics found that the sewage plant, automobile tail gas, sewage irrigation is kind of cultivated land area in cadmium pollution is the main source of, and chemical fertilizer and pesticide, of plastic sheeting will to cultivated land to bring a certain degree of cadmium pollution.