To investigate the effect of land use on soil nitrogen and its transformation in the slightly saline soil

soils under four types of land use were employed

i.e.

orchard

vegetable

cropland and unused new sedimentation land in Kenli Count y of Yellow River Delta.The results showed that the greatest total nitrogen in top soil layer(0-20 cm)was in the cropland

followed by orchard and vegetable land

and t he least was in unused new sedimentation land soil.The mean value from the greatest to the least was 1.42

1.17

0.97 and 0.57 g / kg

respectively.In 20)40 cm soil layer

the average concentration of the total nitrogen was 0.86 g/ kg in vegetable soil

which is higher than that in the other three land use types.The average concentration of NO3-)N in 0-20 cm vegetable soil layer is 27.25 m g/ kg

far higher than that in orchard

cropland and unused new sedimentation land

while NH4+)N in different land use types was similar

ranging from 2.65 to 4.09 mg/kg.Soil NO3-)N and NH4+)N concent ration in 20-40 cm layer in different land use soils showed the similar changes as those into player(0-20 cm).Through the correlation analysis

the available nitrogen in vegetable soil was mainly from fertilization

and the available nitrogen in orchard and crop land soils was closely correlated with the total nitrogen and was little affected by environment change.The concentration and transformation of nitrogen in unused new sedimentation land soil reflected the initial status of the study area.