施用硫酸铵对酸性紫色土硝化作用的影响.doc


施用硫酸铵对酸性紫色土硝化作用的影响#
熊仕娟,苏静,闫小娟,蒋先军**
(西南大学资源环境学院,重庆 400715)
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摘要:以重庆北碚区酸性紫色土为研究对象,设置 0、100、200 mg/kg 三个不同浓度的
(NH4)2SO4 处理,采用室内恒温(28±1℃)培养的方法,研究了施用不同量的氮肥对紫色
土硝化作用的影响。结果表明,在培养 0 到 14 天,0、100、200 mg·kg-1 (NH4)2SO4 处理
均促进了土壤的硝化作用,净硝化率分别为 、、 mg·(kg · d)-1,土壤 pH 值分别
降低了 、、 个单位,施用的氮肥量越大,土壤硝化作用越强,pH 下降越多。
培养 14 天后,各处理土壤 NH4+-N 和 NO3--N 含量的变化均趋于平缓,硝化作用停止,0、
100、200 mg/kg 处理土壤净硝化率分别降至 、-、- mg·(kg · d)-1,土壤 pH
分别回升至 、、。
关键词:铵态氮肥;酸性紫色土;硝化作用;土壤酸化
中图分类号:S153
Effects of (NH4)2SO4 on nitrification of acidic purple-soils
XIONG Shijuan, SU Jing, YAN Xiaojuan, JIANG Xianjun
(Southwest University,Chongqing 400715)
Abstract: An acidic purple-soil from Beibei District of Chongqing was collected to study the
effects of different rates of ammonium sulfate by 0,100,200 mg/kg on nitrification, an incubation
experiment with constant temperature (28±1℃)was carried out. Nitrification increased with
ammonium sulfate added by 0,100,200 mg·kg-1 during incubation of 0-14, nitrification
rates was ,, mg·(kg · d)-1 , respectively. pH decreased by ,, pH units.
Results indicated that greater addition of (NH4)2SO4 led to a greater nitrification and greater
decrease in soil pH in the first stage of incubation. However, net nitrification rates deceased to
,-,- mg·(kg · d)-1 , meanwhi