长期定位施肥对土壤氮素矿化与作物产量的影响

揭示长期施用有机肥及配施氮肥对非石灰性潮土氮素矿化特性的影响,探索其与作物产量间的关系。以始于_1978年的莱阳长期定位施肥试验为基础,采用田间原位-离子交换树脂法(ISC-IERB)研究了长期定位施肥对土壤氮素矿化特性的影响,并对其与产量进行了相关分析。结果表明:长期施用有机肥及其配施氮肥可显著提高非石灰性潮土全氮、矿质氮、净氮矿化量、冬小麦或夏玉米吸氮量和产量,且在同一有机肥(氮肥)水平下,均随氮肥(有机肥)投入量的增加呈增加趋势,其中高量有机肥配施高量氮肥(M_2N_2)处理的增加幅度最高,冬小麦、夏玉米产量分别为6 803,_1_1 935 kg/hm_2;长期施肥使夏玉米季土壤氮净矿化量、净氮矿化率明显大于冬小麦季,施肥处理(M_1、M_1N_1、M_1N_2、M_2、M_2N_1、M_2N_2)的增幅分别为7.1%-2.7%,16.2%-76.0%;相关分析表明,冬小麦-夏玉米产量与当季冬小麦、夏玉米播前土壤全氮、矿质氮含量、氮净矿化量均存在极显著相关性,但与氮素表观淋失量相关不显著。研究表明,施用有机肥、氮肥是提高土壤供氮潜力、作物产量的有效手段,作物与季节是影响土壤氮素矿化的重要因素。

Effect of Long-term Fertilization on Soil Nitrogen Mineralization and Crop Yield

The objective of the test is to reveal the effects of long-term manure and its combination with nitro-gen fertilizer on nitrogen mineralization of non-calcareous fluvo-aquic soil,and exploring the relationship between crop yield and mineralization.Based on the long-term fertilization test in Laiyang,Shandong Province,which was started in 1 978,the effect of long-term fertilization on nitrogen mineralization was studied by ISC-IERB(In-situ Soil Core and Ion Exchange Resin Bag),and the correlation analysis between the crop yield and the mineralization was carried out.Long-term application of organic manure and nitrogen fertilizer could significantly increase the non-cal-careous soil total nitrogen,mineral nitrogen,net nitrogen mineralization,nitrogen uptake and yield of winter wheat or summer maize,and in the same manure(or nitrogen fertilizer)level,the increase of the amount of nitrogen fertilizer (or manure)was increased,among these,the increase of M2 N 2 (combined application of high amount of manure and high amount nitrogen fertilizer)was the highest,and the yield of winter wheat and summer maize respectively were 6 803,1 1 935 kg /ha;long-term fertilization in summer maize season soil nitrogen net mineralization,net nitrogen mineralization rate was significantly greater than the winter wheat season,the increase of fertilization treatment were 7.1 % -62.7%,1 6.2% -76.0%;the correlation analysis showed that the yield of winter wheat and summer maize and pre sowing soil total nitrogen,mineral nitrogen content,net mineralization of nitrogen was significantly relativity, but not significantly relativity with nitrogen leaching amount.Application of organic manure and nitrogen fertilizer is an effective means to increase the potential of soil nitrogen supply,plant and season is an important factor to affect the mineralization of soil nitrogen.