The Trend Variability of Soil Organic Matter Content in the Salinity Region of Yucheng City in Shandong Province

With the help of GPS(Global Position System) and GIS(Geographic Information System),the dynamic variability of soil organic matter(SOM) content was studied in 1980 and 2003 in Yucheng City in Shandong Province of China.One hundred sampling points were selected.Research result indicated the average SOM content in the arable layer was 14.68g kg~(-1) in 2003,an increase of 141.7% compared with that(6.0g kg~(-1)) recorded in 1980.The temporal and spatial variability of SOM content could be expressed by the spherical semi-variance model and ordinary Kriging interpolated method.The article also analysed the change of SOM content in the salinity region.The decrease of salinity content provided good conditions for the increase of SOM content.The research result showed that soil organic matter character is in normal distribution,the SOM had exhibited moderate spatial correlation.