NH_4^+对K^+在土壤肥际微域中迁移和转化的影响  

EFFECT OF NH_4^+ ON MOVEMENT AND TRANSFORMATION OF K^+ IN FERTILIZER MICROSITES IN SOILS

作　　者：杜振宇[1] 周健民[1] 王火焰[1] 杜昌文[1] 陈小琴[1] 

机构地区：[1]土壤与农业可持续发展国家重点实验室(中国科学院南京土壤研究所)

出　　处：《土壤学报》2007年第3期492-498,共7页Acta Pedologica Sinica

基　　金：国家自然科学基金项目(No40071051);国家重点基础研究发展规划项目(NoG1999011802)资助

摘　　要：NH4+和K+共施在农田施肥中是很普遍的现象,研究它们共施后二者在土壤中的交互作用对指导施肥具有重要意义。采用室内土柱实验研究了共施条件下NH4+对K+在红壤和潮土肥际微域中的迁移和形态转化的影响,供试肥料为NH4Cl和KCl。试验结果表明,与单施K+相比,共施NH4+没有改变肥料钾在红壤和潮土中的迁移距离,但提高了肥际微域中的水溶性钾含量;在靠近施肥点附近,NH4+的施用减少了土壤交换性钾含量,这种作用在潮土中的表现不如在红壤中明显;与单施KCl相比,共施NH4Cl明显降低了施肥点附近土壤微域内的非交换性钾含量。研究结果表明,共施NH4Cl减少了土壤晶格对钾离子的固定,增加了钾的淋溶风险。It is a common way to apply NH4^＋ and K^＋ together in farming. Effects of NH4^＋ on movement and transformation of K^＋ in fertilizer microsites in red soil and Fluvo-aquic soil were studied through an incubation experiment using soil columns. The fertilizers used in the experiment were NH4Cl and KCl. Compared with the treatment of application of K^＋ alone, the treatment of addition of NH4^＋ did not show any effect on diffusion distance of fertilizer K but did increase the concentration of waterextractable K in fertilizer microsites. In the soil close to the fertilizer placement site, the concentration of exchangeable K was decreased as a result of the addition of NH4^＋ , which was not so apparent in Fluvo-aquic soil as in red soil. Besides, the addition of NH4^＋ significantly decreased the concentration of nonexchangeble K in fertilizer microsites, suggesting that the addition of NH4^＋ reduced K fixation in soil crystal lattices, thus increasing the risk of K leaching in the two soils.

关 键 词：NH4^+ K^+ 红壤 潮土 迁移 转化 

分 类 号：S153.3[农业科学—土壤学]