长期不同施肥模式对稻田土壤磷素及水稻营养的影响

基于16年长期定位试验，选取了无肥对照(CK)、无肥基础上的有机物循环利用(C)、NPK化肥配施(NPK)、NPK化肥基础上的有机物循环利用(NPK+C)、减量施肥(F+1/2C) 5个处理，通过测定各处理土壤P素肥力指标和水稻植株P含量，研究了不同施肥模式对土壤P素肥力特性和水稻P营养的影响。结果表明，长期不同施肥模式显著改变了0~20 cm土壤P素肥力特性和水稻对土壤P素的吸收利用，对20~40 cm土壤P素肥力影响不大。NPK化肥配施与无肥对照相比，耕层土壤Olsen-P和全P含量分别提高了108.8%和31.9%，各生育期水稻植株P含量(含稻谷)差异显著。NPK化肥配施基础上的有机物循环利用与NPK化肥配施相比，耕层土壤Olsen-P和全P含量分别提高了84.3%和19.4%，土壤P素活化系数达到2.96，差异显著，各生育期水稻植株P含量(稻谷除外)差异显著。无肥基础上的有机物循环利用与无肥对照相比，耕层土壤P素肥力指标、水稻植株P含量(含稻谷)差异均不显著。减量施肥处理与NPK化肥配施相比，土壤肥力性状无明显差异，植株中P含量略有下降，稻谷中P含量差异不显著。施NPK化肥基础上的有机物循环利用明显改善了土壤P素肥力性状，提高了土壤P素活化度，促进了水稻对P素的吸收利用。

Effects of Long-Term Application of Different Fertilizer Patterns on Rice Paddy Soil Phosphorus and Rice Phosphorus Nutrition

16-year experiment was conducted for revealing the long-term impact mechanism of fertilization on soil fertility and crop nutrition. Five treatments including blank (CK), organic nutrient recycling without NPK fertilizer application (C), NPK fertilizer application (NPK), organic nutrient recycling combined with NPK fertilizer application (NPK+C) and reducing fertilizer application (F+1/2C) were selected, and soil phosphorus fertility indicators and rice plant phosphorus content were measured. The results showed that long-term application of different fertilizer patterns changed the phosphorus fertility characteristics in 0–20 cm soil and rice phosphorus nutrition significantly, while did not vary the phosphorus fertility in 20–40 cm soil remarkably. Compared with blank, NPK fertilizer application increased Olsen-P and total phosphorus content in 0–20 cm soil by 108.8% and 31.9% respectively, meanwhile, the phosphorus contents in rice plant and grains of the two treatments had significant difference in all growth periods. In contrast with NPK fertilizer application, organic nutrient recycling combined with NPK fertilizer application increased Olsen-P and total phosphorus content in 0–20 cm soil by 84.3% and 19.4% respectively, meanwhile, the soil phosphorus activation coefficient achieved 2.96, indicating that the phosphorus content of these two treatments in plant(except grains)had significant difference in all growth periods. There was no significant difference between treatments of organic nutrient recycling alone and blank onsoil fertility indicators and the phosphorus contents in plant and grains in all growth period. And also, there was no obvious difference between treatments of reducing fertilizer application and NPK fertilizer application on soil fertilizer characteristics and phosphorus contents of plant and grains. Compared with NPK fertilizer application, reducing fertilizer application decreased rice plant phosphorus content slightly. Organic nutrient recycling combined with NPK fertilizer application improved soil phosphorus fertility characteristics prominently, raised soil phosphorus activation degree, and promoted the absorbtion of phosphorus in rice.