Effects of nitrogen deposition on soil nutrient content of Deyeuxia angustifolia

Taking the marsh meadow Deyeuxia angustifolia in San Jiang Plain of Northeast China as test material,a field experiment was carried out with treatments different in nitrogen supply(0,4,8g/m²) to investigate the effects the soil nutrient content.The results showed that difference among layers soil organic matter activity firstly increased and then decreased with increasing of nitrogen addition. Difference among layers soil total nitrogen contains were no significant differences. Soil total nitrogen contains reduced gradually in the 0-10cm layers,in the 10-20cm and 20-30cm layers firstly increased and then decreased. Difference among layers soil ammonium N contains were no significant differences.The 0-10cm and 20-30cm layers soil total NO_-³-N firstly increased and then decreased,10-20cm layers firstly decreased and then increased. Difference among layers soil nitrate N contains obviously different levels(p<0.05). With increasing of nitrogen addition, the 0-10cm and 10-20cm layers soil total phosphoru contains increased gradually,20-30cm layers firstly increased and then decreased. With increasing of nitrogen addition,difference among layers soil total potassium contains were no significant differences.