晋南麦区土壤钾素状况与小麦施钾效应

对晋南麦区钾素和钾应用效果的调查与研究表明 :①随着农业生产水平的日益提高 ,晋南麦区土壤速效钾的含量与第二次土壤普查时相比呈下降趋势 ,下降幅度以潮土 >褐土 ;盆地 >丘陵>塬地 >山区 ;同一生态区域内 ,低肥力 >高肥力 >中肥力。②土壤速效钾含量≤ 10 0mg/kg时 ,小麦施用钾有明显的增产效果。③在合理施用有机肥、氮磷化肥的基础上 ,每公顷施氧化钾 75～2 2 5kg ,每公斤氧化钾增产小麦 2 .16～ 4 .2 2kg ,增产幅度以高肥力 >中低肥力。④目前 ,晋南麦区钾肥的适宜用量为每公顷施氧化钾 135～ 180kg ,以全部作基肥且集中条施效果最佳

Soil Potassium of Wheat-growing Area in the South of Shanxi and the Effect of Applying Potash on Wheat

The investigation results of soil potassium in Southern Shanxi and application effect of potash showed that ①the amount of soil available k decreased in wheat growing area in Southern Shanxi compared the result of Second Soil Investigation,the decreasing range was as following:aquept soil > drab soil,basin area>hilly area>high plate>mountainous area,low fertility>high fertility>middle fertility; ②applying potash to wheat had obvious effect of increasing yield when the content of soil available K was equal or lower than 100 mg/kg;③besides applying manure,nitrogen and phosphorus fertilizers,the amount of potash K 2O should be 75～22 kg/hm 2,yield increase rate was 2.16～4.22kg wheat/kg K 2O,yield increase range was higher in high fertility soil than in middle and low fertility soil;④the suitable potash K 2O amount for wheat yield in Southern Shanxi was 135～180kg/hm 2,best to use as base fertilizer and fertilize in rows.