几种吡啶类化合物对土壤硝化的抑制作用比较

Comparative studies on soil nitrification inhibition by pyridine compounds

为了探明吡啶类化合物对土壤硝化作用的抑制效应,采用室内微宇宙试验,研究了2-氯-6（三氯甲基）硫酸盐、2-氯-6（三氯甲基）盐酸盐、吡啶混合物和吡啶X类化合物对潮土、红壤和水稻土中铵态氮硝化的抑制作用。结果表明,在35 d培养期内,吡啶类化合物处理土壤硝态氮含量明显低于对照（未添加吡啶类化合物）,吡啶类化合物对土壤中铵态氮的硝化抑制率介于2.91%~91.92%,抑制强度先逐渐升高后降低,在培养21 d时抑制强度达到峰值。不同类型吡啶类化合物对土壤中铵态氮的硝化抑制效果存在差异,吡啶盐酸盐类化合物优于其他几类化合物;吡啶类化合物对土壤中铵态氮的硝化抑制作用与土壤类型有关,对3种土壤中铵态氮的硝化抑制作用表现为潮土〉水稻土〉红壤。就同一土壤而言,硝化抑制强度随着吡啶类化合物用量的增加而增加。

Nitrification inhibition is a well-established fertilizer management that improves fertilizer use efficiency（FUE） in crop production aimed at enhanced profitability,crop quality and healthy environment.As a nitrification inhibitor,pyridine compound has been used for stabilization of fertilizer nitrogen（N） for more than 20 years now.However,pyridine compound represents a broad class of heterocyclic N compounds whose activity as nitrification inhibitors appears to be impacted by Cl and/or trichloromethl sub-stitution on C atoms immediately adjacent to the N ring.In addition,the solubility of pyridine compounds in water is very low;which decreases nitrification inhibitory activity.To prove nitrification inhibitory effects,2-chloro-6（3-chloromethylthiazole）-sulfate,2-chloro-6（3-chloromethylthiazole）-chloride,pyridine compounds mixture and pyridine X compounds were investigated for inhibi-tory effects on nitrification of fluvo-aquic soil,red soil and paddy soil using laboratory microcosm experiments.The results showed that nitrate contents in soils treated with pyridine compounds were significantly lower than those of the control.Nitrification inhibi-tion rate range was 2.91%~91.92%.Inhibitory effect of pyridine compounds on soil nitrification increased before 21 d,after which it decreased,with peak effect on 21st d.Differences were noted among inhibitory effects of different pyridine compounds.The effects of 2-chloro-6（3-chloromethylthiazole）-chloride were much stronger than those of other pyridine compounds.Differences were also noted in inhibitory effects of pyridine compounds on nitrification in fluo-aquic soil,red soil and paddy soil.Inhibitory effects of pyri-dine compounds in the different soils were in the order of： fluvo-aquic soil paddy soil red soil.Based on soil type,pyridine com-pound inhibition effect on nitrification increased with increasing application rate the compounds.