Abstract:

A geostatistic method in combination with GIS was applied to characterize and map the spatialtemporal variability of soil pH in the typical area of Taihu Lake Region. The soil of the studied area appeared to be acid with about 85% of the total area showing a trend of decline in soil pH and its average decline extent being about 0.56 pH units. Since the Second Soil Survey, the soil pH spatial autocorrelation has become stronger and its autocorrelated distance has turned shorter, indicating that the soil pH distribution pattern has become complex. Based on the background information, it could be deduced that these changes had resulted from continual application of chemical fertilizers and large amount of acidic waste materials discharged from factories over last 20 years.

Key words: soil acidity, spatial temporal variability, geo statistics, Taihu Lake region