论文部分内容阅读
【目的】研究地表覆盖对黄土高原旱地冬小麦氮磷钾需求和生理效率的影响,为促进黄土高原旱地冬小麦高效优质生产提供可靠的理论依据和实践经验。【方法】通过田间试验,以裸地休闲为对照,研究地膜覆盖、秸秆覆盖、种植绿肥和秸秆覆盖+种植绿肥对冬小麦籽粒产量、籽粒养分含量、籽粒产量形成和籽粒养分含量形成的氮磷钾需求及生理效率的影响。【结果】地膜覆盖降低了籽粒产量形成的需氮量,提高了籽粒产量形成的氮生理效率,从而使冬小麦籽粒产量显著增加6%;秸秆覆盖降低了地上部吸氮量,使籽粒产量减少7%;种植绿肥和秸秆覆盖+种植绿肥提高了籽粒产量形成的氮磷钾养分需求量、降低了籽粒产量形成的养分生理效率,从而使籽粒产量均减少5%。地膜覆盖提高了籽粒氮含量形成的需氮量,降低了氮生理效率,从而使籽粒含氮量降低8%,地膜覆盖增加了地上部吸钾量,使籽粒含钾量增加4%;秸秆覆盖的籽粒含氮量降低4%,但它的籽粒磷和钾含量分别提高6%和4%,这与降低籽粒磷钾含量形成的养分需求量、提高磷钾生理效率有关;种植绿肥提高了籽粒氮含量形成的氮生理效率,从而使籽粒氮含量增加8%;秸秆覆盖+种植绿肥对籽粒氮和磷含量无显著影响,但籽粒含钾量增加4%,归因于提高了籽粒钾含量形成的钾生理效率。【结论】地膜覆盖降低籽粒产量形成的需氮量,提高籽粒产量形成的氮生理效率,从而提高籽粒产量;但增加了籽粒氮含量形成的需氮量、降低了籽粒氮形成的氮生理效率,不利于籽粒含氮量提高。秸秆覆盖不利于作物养分吸收,从而影响籽粒产量和养分含量形成。种植绿肥和秸秆覆盖+种植绿肥提高了籽粒氮磷钾养分需求量、降低它们的生理效率,从而降低籽粒产量。种植绿肥可提高籽粒氮含量形成的氮生理效率,从而提高籽粒氮含量。因此,旱地小麦生产中为保证籽粒产量和营养品质,需增加地膜覆盖和秸秆覆盖的氮肥用量;夏闲期种植绿肥是旱地土壤培肥的重要措施,但需注意其可能带来的减产风险,应结合区域降水情况因地制宜。
【Objective】 The objective of this study was to investigate the effects of surface mulching on N, P and K demand and physiological efficiency of winter wheat in dryland of Loess Plateau, and to provide reliable theoretical basis and practical experience for promoting high and efficient winter wheat production in dryland of Loess Plateau. 【Method】 Field experiments were conducted to study the effects of plastic film mulching, straw mulching, planting green manure and straw mulching + planting green manure on the grain yield, grain nutrient content, grain yield and grain nutrient content of winter wheat, Demand and Physiological Efficiency. 【Result】 Film mulching reduced the nitrogen requirement for grain yield and increased the nitrogen physiological efficiency of grain yield, which increased the grain yield of winter wheat significantly by 6%. Straw mulching reduced the nitrogen uptake in shoot and decreased grain yield by 7 %; Planting green manure and straw mulching + planting green manure increased the N, P and K nutrient requirements formed by grain yield and reduced the nutrient physiological efficiency of grain yield formation, thus reducing the grain yield by 5%. The plastic film mulching increased nitrogen demand and reduced nitrogen physiological efficiency, thus reducing the nitrogen content of the grain by 8%. The mulching increased the potassium uptake in the shoot and increased the potassium content in the grain by 4% Of the grain nitrogen content decreased by 4%, but its grain phosphorus and potassium content increased by 6% and 4%, respectively, which is related to reducing the nutrient demand formed by phosphorus and potassium content of grain and increasing the physiological efficiency of phosphorus and potassium; planting green manure increased the grain Nitrogen content of the formation of nitrogen physiological efficiency, so that the grain nitrogen content increased by 8%; straw mulching + planting green manure on nitrogen and phosphorus content of the grain had no significant effect, but the grain potassium content increased 4%, due to increased grain K formation The physiological efficiency of potassium. 【Conclusion】 Film mulching can reduce the nitrogen requirement for grain yield and increase the physiological efficiency of nitrogen formed by grain yield, thus increase the grain yield; but increase the nitrogen requirement for grain nitrogen formation and reduce the nitrogen physiological efficiency of grain nitrogen formation, Not conducive to raising the grain nitrogen content. Straw cover is not conducive to crop nutrient absorption, thus affecting the grain yield and nutrient content formation. Planting green manures and straw mulching + planting green manure increased the N, P and K nutrient requirements of grain, reduced their physiological efficiency, and reduced grain yield. Planting green manure can increase the nitrogen physiological efficiency formed by the nitrogen content of the grain, thereby increasing the nitrogen content of the grain. Therefore, in dryland wheat production, in order to ensure grain yield and nutritional quality, it is necessary to increase the amount of nitrogen fertilizer mulching and straw mulching; green manure cultivation in summer is an important measure for soil fertility development in dryland, but pay attention to the risk of yield reduction, Should be combined with regional precipitation situation according to local conditions.