Evaluation of the acetylene-inhibition technique for the measurement of denitrification in grassland soils
Evaluation of the acetylene-inhibition technique for the measurement of denitrification in grassland soils
复制标题
乙炔抑制技术在草原土壤反硝化测量中的评价
DOI：
10.1002/jsfa.2740331205
复制
发表时间：
1982
影响因子：
4.1
通讯作者：
Keith Dawson
中科院分区：
文献类型：
--
作者：
J. Rydén;Keith Dawson
对乙炔抑制技术在两种草下土壤反硝化作用的常规野外测量中的适用性进行了评估。通过垂直插入土壤的探头的径向扩散将乙炔引入土壤空气中，并使用土壤覆盖物，通过乙炔处理土壤中氧化亚氮(N2O)的损失来确定总反硝化作用。乙炔浓度为0.1%~1.0%(v/v)，能有效地抑制土壤中N2O的还原，在田间条件下开始向土壤供应乙炔后1~2小时内，土壤中的N_2O通量达到平衡。田间持水量降雨后土壤处理和平衡时间较长，而春夏秋三季土壤含水率低于田间持水量时处理和平衡时间较短。经乙炔处理的土壤N2O通量的空间变异性一般为±25%，可能与土壤中充气孔隙的变异性有关。常规反硝化测量中要求的重复处理并没有影响土壤无机氮在NH4+和NO3之间的分配，这表明乙炔同时抑制硝化作用并不是该技术田间应用的重要制约因素。乙炔抑制N2O还原的效率不受土壤重复处理的影响，也没有任何乙炔分解的证据。重复处理不影响牧草的干物质产量和矿物质含量。这项研究的结果表明，乙炔抑制技术可以应用于常规的反硝化测量，无论是小块还是大块的化肥N去向的小区研究。
The acetylene inhibition technique has been evaluated for its suitability for routine field measurements of denitrification in two soils under grass. Acetylene was introduced into the soil air by radial diffusion from probes inserted vertically into the soil and, using a soil cover, total denitrification was determined as the loss of nitrous oxide (N2O) from the acetylene-treated soil. Acetylene concentrations of 0.1–1.0% (v/v), which are effective in inhibiting the reduction of N2O, were established within 1–2 h of commencing the supply of acetylene to soil at field capacity; the N2O flux equilibrated within the same period. Treatment and equilibration times were longer after rainfall on to a soil at field capacity and shorter in spring, summer and autumn when soil water content was less than field capacity. Spatial variability in N2O flux from acetylene-treated soil was generally ±25% and was probably associated with variability in air-filled pore spaces in the soil. Repeated treatments, as required in routine measurements of denitrification, did not affect the distribution of soil inorganic N between NH4+ and NO3- which suggests that concurrent inhibition of nitrification by acetylene was not a significant constraint in the field application of the technique. The efficiency with which acetylene inhibits the reduction of N2O was not affected by repeated treatments of soil nor was there any evidence for acetylene decomposition. Repeated treatments did not affect dry matter yield or mineral contents of herbage. The findings of this study suggest that the acetylene-inhibition technique may be applied to routine measurements of denitrification in both small and large plot studies of the fate of fertilizer N.