冬小麦-夏玉米轮作区土壤磷与磷肥产量效应变化

Trends of Yield Responses to Soil Phosphorus and Phosphate Fertilizer in Winter Wheat-Summer Maize Rotation System

为了给作物持续高产下科学施用磷肥提供依据,采用1978年以来土壤有效磷变化的大数据分析、不同时段磷肥定位试验、大面积磷肥产量效应试验等方法分析了冬小麦-夏玉米轮作区土壤有效磷变化、土壤和肥料磷的产量效应。结果表明,冬小麦-夏玉米轮作区土壤有效磷含量平均为22.43 mg/kg,表现为太行山山麓平原﹥冲积平原。1996—1999年,太行山山麓平原、冲积平原区供试土壤有效磷含量分别为15.09,11.90 mg/kg,冬小麦P_(2)O_(5)用量180 kg/hm^(2)时土壤供磷能力:冬小麦分别为83.9%,75.8%,夏玉米分别为83.3%,89.7%。冬小麦秸秆还田下,土壤磷收支表观平衡分别为盈余52.8%,55.4%。2010—2012年,太行山山麓平原土壤有效磷27.22 mg/kg,冬小麦、夏玉米P_(2)O_(5)用量分别为108,60 kg/hm^(2)时土壤供磷能力:冬小麦为84.6%,夏玉米为90.1%。小麦秸秆不还田下,土壤磷收支表观平衡:冬小麦盈余6.7%,夏玉米亏缺47.1%。基于2002—2006年,2012—2016年多点大面积磷肥在冬小麦、夏玉米上的效应函数计算出最高产量P_(2)O_(5)用量:冬小麦分别为107.3,125.1 kg/hm^(2),夏玉米分别为52.0,58.9 kg/hm^(2)。过量施用磷肥连续种植3 a 6茬,土壤积累磷均表现出显著的增产效应。冬小麦-夏玉米轮作秸秆还田下,冬小麦、夏玉米推荐P_(2)O_(5)用量分别为90~100,30 kg/hm^(2);秸秆不还田分别为100~120,45 kg/hm^(2)。

This study investigated the dynamics of soil phosphorus,yield responses to soil phosphorus and phosphate fertilizer in winter wheat-summer maize rotation system in the last decades,which was important for the scientific application of phosphate fertilizer in continuous high-yielding cropping.A combined method that included in situ phosphate fertilizer experiment under different soil fertility conditions,the analysis of changes of soil available P since 1978,the response of yield to phosphate fertilizer was used.Average content of soil available P of winter wheat-summer maize rotation area was 22.43 mg/kg,and the soil available P of the piedmont plain of Taihang mountain was greater than the alluvial plain.During 1996—1999,the soil available P content of the the piedmont plain and the alluvial plain was 15.09,11.90 mg/kg in cultivated land,respectively,the application rate of P_(2)O_(5) in the winter wheat season of the rotation system was 180 kg/ha;the soil P supply capacity for winter wheat in these two regions piedmont were 83.9%,75.8%,respectively,and for summer maize they were 83.3%,89.7%,respectively.Under the condition of winter wheat straw returning,soil P surplus of these two regions was estimated to be 52.8%,55.4%,respectively.During 2010—2012,the soil available P of the piedmont plain of Taihang mountain was 27.22 mg/kg,the application rate in winter wheat and summer maize season were 108,60 kg/ha,respectively.The soil P supply capacity in winter wheat season was 84.6%,90.1%in summer maize season.Soil P surplus was estimated to be 6.7%in winter wheat season,and soil P of deficit was estimated to be 47.1%in summer maize season without straw returning.The application rate of P_(2)O_(5) for the maximal yield production of winter wheat and summer maize were calculated according to the yield responses of winter wheat and summer maize to the P fertilization rates at multiple sites during 2002—2006 and 2012—2016.For winter wheat they were 107.3,125.1 kg/ha,respectively,and for summer maize they were 52.0,58.9 kg/ha,respectively.The accumulated P increaded the yield of winter wheat and summer maize for excess application 3 time of P fertilizer in 3 years 6 crop.The recommendation of P_(2)O_(5) rate for winter wheat and summer maize with wheat straw returning were 90—100 kg/ha and 30 kg/ha,respectively,and they were 100—120 kg/ha and 45 kg/ha without wheat straw returning.