湖南不同地区早稻施钾效应及土壤速效钾丰缺指标研究

K Fertilizer Effect of Early Rice and Abundance and Deficiency Indices of Soil Available K in Different Regions of Hunan Province

为研究施钾对早稻的产量及经济效应的影响,并建立湖南省早稻土壤速效钾的丰缺指标,2005～2008年在湖南省双季稻主产区按湘北、湘中-湘东及湘南3个区域共布置110个钾肥早稻田间试验。结果表明,早稻施钾具有明显的增产效果及经济效应,增产及增收效果均表现为:湘南中低山、丘陵区>湘北环洞庭湖平原、低山丘陵区>湘东-湘中丘陵、中低山区。研究还表明土壤速效钾对施钾增产效应及经济效益有显著影响,施钾增产幅度及经济回报均随土壤速效钾含量的提高而降低。最后建立了湖南省早稻种植体系这3个区域土壤速效钾"低"、"中"、"高"丰缺指标。

In order to study the effect of potassium fertilizer（K） application on yield and profit of early rice and construct the abundance and deficiency indices of rice soil available K in Hunan Province,110 field trails of K fertilizer application for early rice were conducted in three main double-rice cropping regions of Hunan Province（Northern Hunan,Middle Hunan-Eastern Hunan and Southern Hunan） during 2005～2008.The results showed that K fertilizer application significantly increased yield and profit of early rice.The ranking order of yield increase and profit rate among three study areas were the south regionthe north regionthe east-central region.The results also indicated that soil available K significantly affected K fertilizer effect in increase of yield and profit,and the yield increment and the profit increase all decreased with increasing soil available K content.In the end,the abundance and deficiency indices（low,medium and high） of soil available K in the three regions for early rice planting system in Hunan Province were established.