不同硝化抑制剂对红壤氮素硝化作用及玉米产量和氮素利用率的影响

本研究分析添加不同种硝化抑制剂及其组合的高效稳定性氯化铵氮肥对红壤硝化作用、玉米产量和氮肥利用率的影响,旨在筛选出适合酸性红壤的高效稳定性氯化铵态氮肥。在氯化铵中分别添加硝化抑制剂2-氯-6-三甲基吡啶(CP)、3,4-二甲基吡唑磷酸盐(DMPP)和双氰胺(DCD)及其组合,制成6种高效稳定性氯化铵态氮肥,以不施氮肥(CK)和施氯化铵(N)为对照,进行等氮量玉米盆栽试验。结果表明: 与N处理相比,CP+DMPP和DMPP+DCD处理红壤中铵态氮含量提高56%～62%,显著高于CP、DMPP和DCD处理;土壤表观硝化率显著降低33%～34%。添加硝化抑制剂及其组合的6个处理均显著提高了玉米生物量和氮肥吸收利用率。与N处理相比,单独添加硝化抑制剂处理生物量均显著高于硝化抑制剂组合处理,平均提高1.3倍;添加DCD处理效果最显著,玉米籽粒产量、吸氮量和氮肥吸收利用率分别显著提高4.1、6.3和4.4倍。为了达到既能低成本又能提高产量和氮肥利用率的效果,在红壤上添加硝化抑制剂DCD是最佳选择。

Effects of different nitrification inhibitors on nitrification,maize yield,and nitrogen use efficiency in red soil

We examined the effects of nitrification inhibitors (NIs) on soil nitrification, maize yield and nitrogen use efficiency (NUE), aiming to screen out high efficiency stabilized ammonium chloride fertilizer in red soil. Nitrification inhibitors 2-chloro-6-trimethyl-pyridine (CP), 3, 4-dimethyl-pyrazolate phosphate (DMPP), and dicyandiamide (DCD) and their combinations were added into ammonium chloride (NH₄Cl) to make six stabilized nitrogen fertilizers. With blank (CK) and NH₄Cl (N) as the controls, we conducted a maize pot experiment with the same amount of nitrogen addition. The results showed that compared with the treatment of N, soil ammonium content in CP+DMPP and DMPP+DCD increased by 56%-62%, which was significantly higher than that in CP, DMPP, and DCD, while the apparent nitrification rate of red soil was significantly reduced by 33%-34%. All the six treatments with nitrification inhibitors and their combinations significantly improved biomass and nitrogen absorption efficiency of maize. Compared with the N treatment, the application of adding NIs alone was significantly higher than that of the treatments of NIs combinations, with an average of 1.3 times increase. DCD was the most efficient one in improving maize yield, nitrogen uptake, and nitrogen adsorption efficiency, which increased by 4.1, 6.3 and 4.4 times, respectively. Comprehensively, DCD performed the best in reducing cost and improving yield and nitrogen use efficiency in red soil.