不同施肥方式对典型壤质潮土中微量元素积累及其有效性的影响  

INFLUENCE OF DIFFERENT LONG-TERM FERTILIZATION PRACTICES ON ACCUMULATION AND AVAILABILITY OF MICRONUTRIENTS IN TYPICAL LOAMY FLUVO-AQUIC SOIL

作　　者：王擎运[1,2] 张佳宝[1] 赵炳梓[1] 邓西海[1] 信秀丽[1] 钦绳武[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) 封丘农田生态系统国家试验站,南京210008 [2]中国科学院研究生院,北京100049

出　　处：《土壤学报》2012年第6期1104-1113,共10页Acta Pedologica Sinica

基　　金：国家重点基础研究发展计划(973计划)(2011CB100506);国家小麦产业技术体系项目(CARS-03-02A);中国科学院知识创新工程重大项目(KSCX2-EW-N-08)资助

摘　　要：研究了1989—2009年间长期不同施肥方式对华北地区典型壤质潮土微量元素全量及有效性的影响。田间试验施肥处理包括:有机肥(OM)、1/2OM+1/2化肥氮磷钾(NPK)、NPK、NP、PK、NK和不施肥(CK),每个处理4个重复。结果显示,经过长期不同施肥,铁(Fe)、锰(Mn)、铜(Cu)、锌(Zn)等微量元素在表层土壤(0～20 cm)中均有一定积累,与其在不同土层中的迁移有关。形态分级提取结果表明,土壤中有效态铁(DTPA-Fe)、铜(DTPA-Cu)、锌(DTPA-Zn)含量高于其在碱性土壤中的最低标准,而有效态锰(DTPA-Mn)的含量则相对较低;残渣态(Residual-fraction)是微量元素在土壤中的主要形态,分别占其全量的>90%(Fe)、>54%(Mn)、>70%(Cu)、>70%(Zn)。有机质在土壤中的积累通过多种机制提高了有效态、弱酸溶解态(Acid-soluble-fraction)及可氧化态(Oxidizable-fraction)微量元素的含量,有效缓解了土壤有效态锰含量的不足,抑制了磷与锌的沉淀反应,是影响微量元素形态转化的主要原因。钾肥的施用同样提高了有效态及弱酸溶解态微量元素的含量,但降低了铁、锰在表层土壤中的全量;而磷肥施用则通过沉淀反应降低了有效态及弱酸溶解态微量元素的含量,提高了铜、锌在表层土壤中的全量。Micronutrient deficiency is commonly demonstrated in farmlands of fluvo-aquic soil, a typical soil type in the Huang-Huai-Hai Plain of China. The objectives of this study were to explore effects of different long-term fertilization practices on balance of mieronutrients in the soil, and changes of soil micronutrients in fraction using the BCR sequential extraction method. A field experiment, designed to have 7 treatments, i.e. OM （Organic Manure） , 1/20M ＋ 1/2 （ Fertilizer） NPK, NPK, NP, PK, NK, and CK （ No Fertilizer） , was laid out and started in 1989. After more than 20 years of fertilization, various extents of accumulation of micronutrients were observed in the surface layer soil （0 - 20cm） , and found to be greatly affected by their transfer between different soil layers. Results of sequential extraction show that the contents of soil available （DTPA-micronutrient） Fe, Cu and Zn were higher, while the content of soil available Mn was relatively lower than the critical levels in the other alkalic soils. The Residue-Fractions of soil Fe （ 〉 90% ） , Cu （ 〉 65% ） and Zn （ 〉 70% ） accounted for a high proportion of their respective total. Interestingly, DTPA, acid soluble and oxidizable fractions of soil micronutrients accumulated more with the increasing soil organic matter level, which was probably the driving factor for the changes of soil micronutrients in fraction. Long term application of K fertilizers also increased DTPA and acid soluble fractions of soil micronutrients, but decreased the total of Fe and Mn in the surface soil layer, while long-term application of P fertilizers decreased the contents of DTPA and acid soluble fractions of soil micronutrients through precipitation, but increased the totals of Cu and Zn.

关 键 词：长期施肥 微量元素 生物有效性 形态 潮土 

分 类 号：S158.3[农业科学—土壤学]