[Application of DNDC model in estimating cropland nitrate leaching].
Hu Li, Li-Gang Wang, Jianjun Qiu · PubMed · 2009
The leaching amount of soil water and nitrate from winter wheat field under typical planting system in Jinan City of Shandong Province was measured with lysimeter during the whole growth season in 2008, and the feasibility of applying DNDC model to estimate this leaching amount was tested by the obtained data. On the whole, DNDC model could better simulate the soil water movement in the crop field, with the accuracy being acceptable. However, there existed definite deviation in the simulation of nitrate leaching. The simulated value (18.35 kg N x hm(-2)) was 3.46 kg N x hm(-2) higher than the observed value (14.89 kg N x hm(-2)), with a relative error of about 20%, which suggested that some related parameters were required to be further modified. The sensitivity test of DNDC model showed that cropland nitrate leaching was easily to be affected by irrigation and fertilization. It was proved that the model had definite applicability in the study area.