长期施肥对褐潮土氮、有机质动态变化的影响

Effect of Long-term Fertilization on N and Organic Matter Dynamic Changes in Fluvo-aqvic Soil

通过北京昌平"国家褐潮土土壤肥力和肥料效益监测基地"的长期定位试验(1991—2003年),研究了长期施肥条件下对褐潮土氮、有机质动态变化的影响。结果表明:氮磷钾化肥配施有机物料提高耕层土壤全氮的效果最为明显,配施有机肥和秸秆处理分别比不施肥增加21.11%和14.35%,明显高于单一施用化肥。长期单施氮肥,或氮磷配合,或氮磷钾配合也显著增加了土壤全氮含量,分别比对照增加10.03%,8.32%和8.40%,而磷钾配合降低了土壤全氮含量。土壤碱解氮含量仍然是氮磷钾配施有机肥或秸杆处理优于单施化肥,分别比对照增加34.97%和32.96%,长期单施氮肥,或氮磷配合,或氮钾配合,或氮磷钾配合,分别比对照增加17.26%,21.55%,23.83%和26.41%。配合施用有机肥处理耕层土壤有机质含量明显高于单施化肥处理;与不施肥比较,NPK+秸秆以及NPK+有机肥处理土壤有机质含量分别增加7.90%和14.56%,氮磷钾配合和氮磷配合分别比对照增加6.51%和5.89%,而单施氮肥仅增加2.56%。可见NPK平衡施用及其配施有机肥对增加土壤有机质含量具有重要作用。

Based on National Supervision Base for Aqui-cinnamon Soil Fertility and Fertilizer Benefits in Changping, Beijing （1991-2003）, the effect of long-term fertilization on N and oranic matter dynamicchanges in fluvo-aqvic soil,the main results obtained：the combined application of NPK with organic materials can increase soil total N content obviously. Both two treatments of NPKM and NPK ＋ straw increased total soil N by 21.11% and 14.35%, respectively, which was higher than that of chemical fertilizer alone markedly. Compared with CK, long-term application of N, NP, and NPK increased soil total N by 10.03%, 8.32% and 8.40%, respectively, while PK treatment decreased soil total N content. Meanwhile, long-term application of N only, NP, NK and NPK increased content of available nitrogen by 17.26% , 21.55% , 23.83% and 26.41% , separately; Both two treatments of NPKM and NPK ＋ straw were greatly superior to the treatment of those chemical fertilizer alone, with the increment of available nitrogen by 34.97% and 32.96%, respectively. The content of soil organic matter（OM） of NPKM treatment was higher than that of single chemical fertilizer treatment significantly. In comparison with CK, soil OM with treatments of NPK ＋ Straw, NPKM, NPK, NP and N only increased by 7.90%, 14.56%, 6.51%, 5.89% and 2.56%, respectively. Therefore, balanced application of NPK, and combined application of NPK with organic materials play a very important role in improving soil OM status.