广西甘蔗种植区土壤钾素肥力分级研究

A Classification System for Potassium Availability in Soils for Sugarcane Planting Regions in Guangxi

关键词:  土壤  速效钾含量  肥力分级  甘蔗种植区

Key words:  soils  soil available potassium content  classification  sugarcane planting regions

摘要:

统计分析1991年至2001年在广西来宾、合浦、贵港、博白等县的红壤、赤红壤和砖红壤上进行的82个施钾肥增产效应田间试验资料,分砂土、壤土、粘土质地对广西甘蔗种植区土壤钾素肥力进行分级。结果表明,甘蔗种植区土壤速效钾肥的临界值为:砂土46.2mg/kg,壤土51.4mg/kg,粘土60mg/kg。砂土、壤土和粘土土壤速效钾肥分级指标分别为:低< 46mg/kg、< 52mg/kg和< 60mg/kg,中46~90mg/kg、52~110mg/kg和60~120mg/kg,高> 90mg/kg、> 110mg/kg和> 120mg/kg.

Abstract:

From 1991 to 2001,82 field experiments were carried out on sugarcane in Laibin,Hepu,Guigang and Bobai Crop response to K as affected by the K status (available K) was measured and statistically analysed.Calculated critical values depended on the soil texture,characterised by sands,loam soils and clays.For sugar cane cultivated on all three soil textures,the calculated critical K values were,46.2,51.2 and 60 mg/kg of available K in sandy,loamy and clayey soils,respectively. Accordingly,potassium supply classes for soils of cultivating sugar cane were established. For the three soil textures,the following supply classes were defined:(1) Low K supply:< 46 mg/kg,< 52 mg/kg and < 60 mg/kg,(2) Medium K supply:46~90 mg/kg, 52~110 mg/kg and 60~120 mg/kg,(3) High K supply:> 90 mg/kg, > 110 mg/kg and > 120 mg/kg,for sandy,loamy and clayey soils,respectively.