摘要
采用15N库稀释-原位培养法研究了硝化抑制剂DCD、DMPP对华北盐碱性褐土氮总矿化速率和硝化速率的影响.试验在山西省运城市种植玉米的盐碱性土壤上进行,设单施尿素、尿素+DCD、尿素+DMPP3个处理.结果表明:施肥后2周,DCD、DMPP分别使氮总矿化速率和氮总硝化速率减少了25.5%、7.3%和60.3%、59.1%,DCD对氮总矿化速率的影响显著高于DMPP,两者对氮总硝化速率的影响无显著差异;而在施肥后7周,不同硝化抑制剂对氮总硝化速率的影响存在差异.施肥后2周,3个处理的土壤氮总矿化速率和硝化速率分别是施肥前的7.2～10.0倍和5.5～21.5倍;NH4+和NO3-消耗速率分别是施肥前的9.1～12.2倍和5.1～8.4倍,这是由氮肥对土壤的激发效应所致.硝化抑制剂使氮肥更多地以NH4+形式保持在土壤中,减少了NO3-的积累.土壤氮总矿化速率和总硝化速率受硝化抑制剂的抑制是N2O减排的主要原因.
By using 15N pool dilution technique in combining with in situ soil cultivation, this paper studied the effects of nitrification inhibitors dicyandiamide （DCD） and 3,4-dimethylpyrazole phosphate （DMPP） on the gross nitrogen （N） mineralization and nitrification rates in a saline-alkali cinnamon soil in North China. The experiment was carried out in a maize-wheat rotation field in Yuncheng City of Shanxi Province, and three treatments were installed, i.e., urea, urea ＋ DCD, and urea ＋ DMPP. In the first two weeks after fertilization, DCD and DMPP made the gross N mineralization rate and gross N nitrification rate decreased by 25.5% and 7.3%, and by 60.3% and 59.1%, respectively, with a significant difference in the gross N mineralization rate but less difference in the gross N nitrification rate between the effects of DCD and DMPP. However, significant difference was observed in the gross N nitrification rate between the effects of DCD and DMPP after seven weeks of fertilization. The gross N mineralization and nitrification rates and the NH4＋ and NO3- consumption rates after two weeks of fertilization were 7.2-10.0, 5.5-21.5, 9.1-12.2, and 5.1-8.4 times of those before fertilization, respectively, possibly due to the stimulating effect of N fertilization. DCD and DMPP made the fertilizer urea N more maintained in NH4＋-N form and less accumulated in NO3--N form in soil. The decreases of the gross N mineralization and nitrifications rate in the test soil due to the effects of the inhibitors would benefit the reduction of N2O emission from the soil.
出处
《应用生态学报》
CAS
CSCD
北大核心
2012年第1期166-172,共7页
Chinese Journal of Applied Ecology
基金
国家科技支撑计划项目(2008BAD95B01)
中国科学院知识创新工程重要方向项目资助
关键词
褐土
硝化抑制剂
15N库稀释技术
原位培养
氮总矿化速率
氮总硝化速率
cinnamon soil
nitrification inhibitor
15N pool dilution technique
in situ culture
gross N mineralization rate
gross N nitrification rate.
