摘要： 通过1992-2012年共20年的长期定位试验,探讨了施用钾肥和秸秆还田对河北省典型潮土区土壤钾肥力的影响,并对长期施肥和秸秆还田处理对土壤全钾含量、土壤速效钾和缓效钾以及农田钾素平衡对速效钾和缓效钾含量的影响等进行了分析。结果发现:连续20年不施用钾肥和秸秆还田,并未对河北省潮土的土壤全钾造成影响;秸秆还田(NPSt)、增施钾肥(NPK)和增施钾肥基础上秸秆还田(NPKSt)显著提高了土壤速效钾含量,提高幅度在44.2%~79.1%;而增施钾肥(NPK)和增施钾肥基础上秸秆还田(NPKSt)显著提高了土壤缓效钾含量,提高幅度在7.66%~37.3%。单施氮磷肥(NP)的土壤速效钾含量没有明显变化,但单施氮磷(NP)和秸秆还田(NPSt)的土壤缓效钾含量分别降低了20.8,9.8 mg/kg。增施钾肥基础上秸秆还田(NPKSt)的农田钾素平衡处于盈余状态,每盈余K₂O 100 kg /hm²,土壤速效钾和缓效钾分别增加2.71,24.4 mg/kg。试验结果表明,增施钾肥和秸秆还田对于提高农田土壤钾肥力具有重要促进作用。

关键词: 长期定位试验, 钾肥, 潮土, 秸秆还田, 土壤钾素状况

Abstract: Long-term field experiment with K fertilization and straw recycling was conducted since 1992 to 2012 in a Fluvo-aquic soil of Hebei Province.The soil total K content,soil available and slow release K content,and the soil K balance were examined in the long term experiment to find the effects of K fertilization and straw recycling on soil K status change.The results showed after 20 years continuous treatments of no K fertilization and straw recycling,there was no significant change in soil total K content;The treatments of NPSt,NPK and NPKSt significantly increased the soil available K content than the initial of about 44.2%-79.1%.And the NPK and NPKSt treatments significantly increased the soil slow release K content of about 7.66%-37.3% than the initial.There was no significant change for NP treatment in soil available K content,but the slow release K content for NP and NPSt treatments decreased about 20.8,9.8 mg/kg respectively.Only the NPKSt treatment got soil K surplus in the 4 treatments,and 100 kg/ha surplus will increase 2.71,24.4 mg/kg,for soil available K and slow release K content,respectively.The experiment showed the positive effect of K fertilization and straw recycling on soil K fertility improvement.

Key words: Long term in-site experiment, Potassium fertilizer, Fluvo-aquic soil, Straw recycling, Soil potassium status

中图分类号: 

• S143.3