The spatial distribution patterns of nitrate nitrogen (NO3-—N) and ammonia nitrogen (NH4+—N)in typical Calamagrostis angustifolia wetland soil s of Sanjiang Plain were studied by Geo statistics method.Results showed that the variability of NO3-—N and NH4+—N contents in different soil layers had significant difference

with the order of NO3-—N > NH4+—N

and the reasons were mainly correlated with the differences of their physical movement characteristics.Further analysis indicated that the differences of NO3-—N and NH4+—N contents in different soil layers or in same soil layer were much significant ( P < 0101).The distribution of NO3-—N and NH4+—N contents in different soil layers had significant spatial structure

which accorded with different semivariogram models.The structure factors had significant effects on there spatial variability

while the effects of random factors were relatively less.Microphysiognomy characteristic was an important random factor to induce spatial heterogeneity

while water condition and soil type were two important structure factors.The maximum spatial variability of NO3-—N and NH4+—N contents in different soil layers were observed in the direction leaning to the depression center.In addition

the studies also indicated that water condition was the main reason to induce the lower NO3-—N content zones to be formed in the lower hypsography of depression

while the alternation of dry and wet was the import reason to inducet he higher NH4+—N content zones to be formed in the lower hypsography of depression.