华北平原不同前茬作物在磷匮乏下对土壤养分和小麦产量的影响

Effects of Different Previous Crops on Soil Nutrients and Wheat Yield under Phosphorus Scarcity in the North China Plain

以华北平原南部两熟作物的搭配为研究对象,在玉米、大豆和花生3种前茬作物的磷常规施用水平基础上,同时设置不施磷肥的磷匮乏水平,同期检测收获后土壤的养分含量及后茬小麦产量及籽粒养分累积量,为华北平原一年两熟制的作物搭配提供理论依据。结果表明,对前茬作物收获后土壤养分而言,在不施磷肥情况下土壤全磷含量表现为大豆前茬处理较高,花生前茬处理与常规施肥处理含量相近;土壤速效磷含量整体表现为花生前茬处理较高;土壤硝态氮和铵态氮含量均表现为大豆前茬处理最高。对后茬小麦而言,小麦千粒质量和产量及小麦籽粒氮、磷累积量和氮肥偏生产力在不施磷肥下均表现为花生前茬处理较高,分别较玉米前茬处理提高0.60%,6.19%,15.46%,18.11%和6.21%,较大豆前茬处理提高2.18%,7.30%,17.66%,13.40%和7.30%。综上,在低磷水平下,为了保证土壤养分平衡,选择花生作为小麦前茬作物是华北平原南部两熟区作物搭配的较优模式。

Under the double cropping pattern in the North China Plain,based on the conventional application level of phosphorus,a phosphorus-deprived level without phosphorus fertilizer was adopted at the same time for three previous crops,corn,soybean and peanut,and then the soil nutrient concentration after previous crop harvesting and the grain yield and nutrient accumulation of winter wheat,the subsequent crop,were examined,to provide a proposal for crops planting in the North China Plain.The results showed that,for the soil nutrients after the previous crop harvesting,the soil total phosphorus concentration was higher in the previous soybean treatment without phosphorus fertilizer,and the concentration in peanut previous treatment was similar to that under conventional fertilizers;the soil available phosphorus content was higher overall in the previous peanut treatment;the soil nitrate and ammonium nitrogen concentrations were both highest in the previous soybean treatment.For post-crop wheat,wheat thousand grains weight,yield,seed N and P accumulation and N fertilizer bias productivity were all higher in the previous peanut treatment without phosphorus fertilizer.The previous peanut treatment increased by 0.60%,6.19%,15.46%,18.11%and 6.21%,respectively,compared to the previous maize treatment,and increased by 2.18%,7.30%,17.66%,13.40%and 7.30%,respectively,compared to the previous soybean treatment.In summary,in order to ensure soil nutrient balance,peanut was selected as a suitable previous crop in summer before winter wheat as a better model for crop mix in the southern two maturity zones of the North China Plain at low phosphorus levels.