黄土高原旱区长期施肥条件下土壤钾素形态空间分布特征及有效性研究  

Research on characteristics of spatial distribution and availability of soil potassium forms under long-term fertilization in the dryland of the Loess Plateau

作　　者：李芳林[1] 郝明德[1,2] 李燕敏[1] 高长青[3] 

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100 [2]中国科学院水利部水土保持研究所,陕西杨凌712100 [3]长武县农业技术推广中心,陕西长武713600

出　　处：《干旱地区农业研究》2009年第3期127-131,142,共6页Agricultural Research in the Arid Areas

基　　金：“十一五”国家科技支撑计划项目(2006BAD05B07,2006BAD09B042);中国科学院知识创新工程重要方向项目(KZCX2-YW-424-3,KSCX1-YW-N15-04)

摘　　要：在黄土高原南部旱地长期肥料定位试验的基础上研究了土壤钾素空间分布特征及其有效性。结果表明：长期施肥后土壤中特殊吸附性钾（SAK）和非特殊吸附性钾（NSAK）储量增加,但水溶性钾（WSK）和非交换性钾（NEK）则有明显的下降,单施N水溶性钾下降了48.24%,单施P下降32.32%,NP配施和NPK配施分别下降10.61%和17.93%,非交换性钾降幅为8.56%-24.91%。增施钾肥可以缓解因长期施肥作物生长所携出的钾素,增加耕层土壤中的水溶性钾、非特殊吸附性钾及特殊吸附性钾。相关分析结果表明,土壤不同形态钾素对速效钾的重要性依次为WSK〉NSAK〉SAK〉NEK,土壤速效钾与水溶性钾、非特殊吸附性钾呈显著相关,与特殊吸附性钾和非交换性钾无显著相关性。Research on characteristics of spatial distribution and validity of soil potassium was carried out in the long-term orientation fertilization experiment. The result showed that there was significant increase of specifically adsorbed potassium （SAK） and non-specifically adsorbed potassium （NSAK） reserves, while the water soluble potassium （WSK） and non-exchangeable potassium （NEK） were obviously decreased. The WSK decrease were 48.24% in the single N treatment, 32.32% in the single P treatment, 10.61% in the combination of N and P treatment, and 17.93% in the NPK treatment. The NEK decrease ranged from 8.56% to 24.91% compared to the non-potassium applying treatment. The applying of potassium could supplement the potassium lost during the plant growing, and increase the content of WSK, NSAK and SAK in the top soil. Correlation analysis results showed that soil available K was significantly correlated with the WSK and NSAK, but not significant correlated with the SAK and NEK.

关 键 词：长期施肥 土壤钾素形态 空间分布 有效性 黄土高原旱区 

分 类 号：S143.3[农业科学—肥料学] S158[农业科学—农业基础科学]