Abstract: The spatial heterogeneity of exchangeable calcium content in 0～20cm horizon in cultivated soils of Shenyang suburbs, Liaoning of China, was investigated, and its map was made by the methods of geostatistics and geographic information system. Data of exchangeable Ca fitted normal distribution after log transformation, and semivariogram fitted a spherical model. Semivariograms indicated that exchangeable Ca content was strongly spatially dependent on the ratio of nugget to sill of 11.7%, its spatially dependent range was 15.8km, and its spatial heterogeneity was fundamentally affected by structural factors such as parent materials and soil types.

Key words: Wavelet transform, Zagunao watershed, Runoff time serial, Scale