Responses to Fertilization of Rice on Cold-waterlogged Paddy Fields Developed from Different Landforms

Field tests were conducted on the typical cold-waterlogged paddy fields (CWPF) developed from different landforms in Minhou, Fujian to study the effect of fertilization on rice productivity, as well as the differences among the paddy fields.The results showed that the rice yield increased with fertilization by 76.5%for the CWPF in the mountain ridge area, 57.6% for the yellow paddy field in the mountain ridge area, 59.0% for CWPF in the flat paddy area, and 43.5% for the grey paddy field in the flat area, as compared to the control.The rate of contribution to the productivity by the soil in CWPF was 6.8-7.0percentage points lower than that of the noncold-waterlogged paddy fields (NCWPF) .But the fertilizer agronomy efficiency of CWPF was 0.1-3.2kg grain per kg fertilizer higher than that of the NCWPF.The grain yield increase due to fertilization of CWPF was 15.5-18.9percentage points higher than that of NCWPF.With or without fertilization, the nutritional content of the grains harvested from CWPF was higher than that of NCWPF.The contribution rate of CWPF soil was lower than that of the soils from NCWPF.However, the effect of fertilization was significantly greater on CWPF than NCWPF.And, fertilization was more likely to increase the production on CWPF than NCWPF.The sensitivity of CWPF in the mountain ridge area to the fertilization was better than that of NCWPF in the flat paddy area.