长期施肥对不同热量带土壤供氮能力的影响

研究利用中国科学院海伦、栾城、鹰潭农业生态试验站长期定位试验,结合温室盆栽,研究了长期施肥对不同热量带土壤供氮能力的影响.为我国不同热量带下农田土壤的生产潜力,平衡施肥等提供理论依据.结果表明:长期不同施肥土壤全氮、碱解氮和矿质态氮含量的高低顺序均表现为:化肥+有机肥 > 化肥 > 无肥.长期施肥对红壤供氮能力的增加幅度最高,其次为潮褐土,最低为黑土,且长期施肥对土壤供氮能力的增加幅度与土壤所处热量带的有效积温呈显著正相关(P<0.05).在长期不同施肥的土壤上种植小麦后,施肥土壤的作物生物量显著高于不施肥土壤(P< 0.05),且作物生物量的变化规律与土壤氮素含量的变化规律大体一致,说明通过生物试验所得的生物量可作为评价土壤氮素肥力的生物学指标.

Influence of Long-term Fertilization on Nitrogen Supply Capacity in Different Thermal Zones Soil

Long-term position experiments were conducted in Hailun, Luancheng and Yingtan Agricultural Ecology Station of Chinese Academy of Sciences together with pot experiment aimed to examine the influence of long-term fertiliza-tion on nitrogen supply capacity in different thermal zones soil. Results showed that under different long-term fertilization, the amount of total N, alkaline N and mineral N decreased in an order of NPKOM > NPK > CK. Long-term fertilization en-hanced the capacity of soil nitrogen supply in different soils with an order of red soil > cinnamon soil > black soil. There was significant positive correlated relationship between the degree of long-term fertilization increased nitrogen supply ca-pacity and the effectively accumulated temperature ( P < 0.05) .In addition,crop biomass of fertilization soil was signifi-cantly higher than no fertilization soil, and the tendency of crop biomass was the same with the tendency of soil nitrogen content. It showed that crop biomass could be chosen as index for evaluating soil nitrogen supplying capacity