中文摘要：

【目的】探讨长期不同施肥处理对土壤微量元素有效含量的影响,为农田管理和农业生产提供参考。【方法】于2012年,在位于黄土丘陵地区陕西安塞的中国科学院水土保持综合试验站川地农田养分长期定位试验场（1997年开始）内,以大豆-玉米-玉米轮作模式的农田土壤为对象,设置氮肥（N,尿素97.5kg/hm~2）、磷肥（P,过磷酸钙75.0kg/hm~2）、有机肥（M,羊粪7 500kg/hm~2）、N＋P、N＋M、P＋M、N＋P＋M、裸地（BL）和不施肥（CK）共9个长期施肥处理,采集0~20和20~40cm土层土样,测定不同土层土壤理化性质及有效铜、有效锌、有效锰和有效铁含量,并对微量元素有效含量进行评价,分析土壤理化性质与微量元素有效含量的相关性。【结果】与CK相比,无论有机肥单施还是与无机肥配施,土壤微量元素的有效含量均显著高于单纯施用化肥土壤,其中土壤有效锌、有效锰和有效铁的平均增幅分别达34.3%,31.5%和40.4%,长期施用氮肥会造成土壤有效锌和有效锰的轻微亏损。相关分析表明,有机质、全氮、碱解氮和速效磷与有效锌、有效锰和有效铁的含量呈极显著正相关关系,而pH则与其为负相关关系。【结论】总体上看,黄土丘陵区农田土壤并不缺乏有效铜,而有效锌、有效锰和有效铁都处于亏缺边缘,施用有机肥可有效改善土壤中微量元素的亏缺状况。

英文摘要：

【Objective】This study determined the effect of long-term fertilization on contents of soil available microelements to provide suggestion the farmland management and agricultural activities.【Method】In 2012,contents of soil microelement and physicochemical properties at layers of 0-20 cm and 20-40 cm under different fertilization treatments N（urea 97.5 kg/hm~2）,P（monocalcium phosphate 75.0kg/hm~2）,M（Composted sheep manure 7 500kg/hm~2）,N＋P,N＋M,P＋M,N＋P＋M,BL,and CK were determined at an alluvial terrace farmland of Ansai Research Station of Soil and Water Conservation in the hilly region of the Loess Plateau,Shaanxi province.Their levels were evaluated and relationships betweencontents of soil available microelements and physicochemical properties were investigated.【Result】Compare to CK,organic manure significantly increased the contents of available microelements than inorganic fertilizer,especially for soil available Zn,available Mn and available Fe with average increase of 34.3%,31.5% and 40.4%respectively.Long-term application of nitrogen fertilizer caused slight loss of available Zn and available Mn.Correlation analysis showed that organic matter,total nitrogen,available nitrogen and available phosphorus positively influenced available Zn,available Mn and available Fe content,while pH correlated with them negatively.【Conclusion】In general,the farmland soil in hilly region had enough available Cu but was lack of available Zn,available Mn and available Fe.Organic manure could improve the condition of soil microelements effectively.