Field experiment and chemical analysis methods were used to study the nutrient characteristics and nutrient effi-ciency of lettuce in 30 different fertility soils at vegetable base of Chongqing. Results showed that nutrient the order of con-tent and uptake by lettuce was phosphorus>nitrogen>potassium in the same yield levels. The change of nitrogen, phos-phorus and potassium contents in different yield levels of lettuce were not obvious, and nutrient uptake by lettuce was differ-ent at three yields levels. Average amount of nitrogen, phosphorus and potassium uptake by lettuce was 17. 9 ~81. 9, 2. 15~11. 3 and 21. 4~129 kg·hm-2 respectively, and the ratios of nitrogen, phosphorus and potassium uptake was in the range of 1. 00∶0. 12∶1. 20 to1. 00∶0. 14∶1. 58. The coefficients of variation of nitrogen, phosphorus and potassium uptake were quite large in the low yield level, and potassium was the largest (61. 50%). The nutrient’s stability was nitrogen>phosphorus > potassium. AE (agronomic efficiency) of nitrogen, phosphorus and potassium were all highest in the low yield level. In all yields levels, AE of phosphorus was the highest (49. 4~99. 2 kg·kg-1) and RE (apparent recovery ef-ficiency) of phosphorus was the lowest ( 6. 6% ~12. 5%) . The SCR ( soil contribute rate ) was 82. 3% >59. 7% >30. 1% from high yield level to low yield level. PE ( Physiological efficiency) of nitrogen, phosphorus and potassium in all yields levels showed no regular pattern.%在重庆蔬菜基地选取30个不同肥力水平的试验田,通过莴苣大田试验和室内分析,研究不同产量水平莴苣氮、磷、钾养分吸收特征和养分效率。结果表明：同一产量水平莴苣养分的平均含量和平均吸收量均表现为钾>氮>磷。不同产量水平的莴苣氮、磷、钾养分含量差异均不明显,受产量影响各养分吸收量差异较大。莴苣氮、磷、钾养分的平均吸收量范围分别为17．9~81．9、2．15~11．3和21．4~129 kg·hm-2,吸收比例范围为1．00∶0．12∶1．20~1．00∶0．14∶1．58。莴苣低产水平氮、磷、钾的吸收变异均较大,其中钾的变异最大(61．50%),氮的吸收最稳定,磷次之,钾的吸收最不稳定。低产水平莴苣氮、磷、钾肥的农学效率均最高。各产量水平中,磷的农学效率最高(49．4~99．2 kg·kg-1),表观利用率最低(6．6%~12．5%)。高、中、低产量水平地力贡献率顺序为82．3%>59．7%>30．1%。各产量水平氮、磷、钾肥料生理效率无明显规律。
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