A model to predict the effects of soil structure on denitrification and N2O emission
A model to predict the effects of soil structure on denitrification and N2O emission
复制标题
预测土壤结构对反硝化和 N2O 排放影响的模型
DOI：
10.1016/j.jhydrol.2011.08.026
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发表时间：
2011
影响因子：
6.4
通讯作者：
Laudone G
中科院分区：
文献类型：
--
作者：
Laudone G
提出了一种土壤孔隙空间模型，并用于反硝化的先验生物物理模拟。该模型包括一个单一的临界渗流通道，通过一个5cm的堆叠的四个单元电池的双孔空隙结构。总之，微孔和大孔结构紧密地复制了来自英国Rothamsted Research经营的Woburn实验农场的桑迪粘壤土的全部保水特性。1 ~ 10个具有生物活性的微孔热点区位于距离表面5cm内的等间距处，距离临界渗滤通道10μm或100μm。硝化和反硝化反应的热点被假定为遵循米氏动力学，速率系数的估计值。还估计了氧浓度的阈值，低于该阈值，厌氧过程将开始。在加入硝酸盐和葡萄糖的含水“修正物”后，孔网络完全饱和，这开始了反应，并且反映了已建立的实验室方案。Fickian和Crank-Nicolson计算的扩散系数取自文献，并针对微孔的弯曲度进行校正。该模型用于显示随时间从模拟土壤中出现的二氧化碳、一氧化二氮和分子氮的量。调整的速率系数和氧阈值浓度，在敏感性分析的范围内，给出了排放曲线与以前的实验测量结果吻合良好。将热点区域定位在远离临界渗流路径的位置，减缓了气体排放的增加和减少。该模型及其参数现在可用于模拟土壤压实和饱和对一氧化二氮排放的影响。
A model of the void space of soil is presented, and used for the a priori biophysical simulation of denitrification. The model comprises a single critical percolation channel through a 5cm stack of four unit cells of a dual-porous void structure. Together, the micro- and macro-porous structures closely replicate the full water retention characteristic of a sandy clay loam soil from the Woburn Experimental Farm operated by Rothamsted Research, UK. Between 1 and 10 micro-porous hot-spot zones of biological activity were positioned at equally spaced distances within 5cm from the surface, and at either 10μm or 100μm from the critical percolation channel. Nitrification and denitrification reactions within the hotspots were assumed to follow Michaelis–Menten kinetics, with estimated values of rate coefficients. Estimates were also made of the threshold values of oxygen concentration below which the anaerobic processes would commence. The pore network was fully saturated following addition of an aqueous ‘amendment’ of nitrate and glucose which started the reactions, and which mirrored an established laboratory protocol. Diffusion coefficients for Fickian and Crank-Nicolson calculations were taken from the literature, and were corrected for the tortuosity of the micro-porosity. The model was used to show the amount of carbon dioxide, nitrous oxide and molecular nitrogen emerging from the simulated soil with time. Adjustment of the rate coefficient and oxygen threshold concentrations, within the context of a sensitivity analysis, gave emission curves in good agreement with previous experimental measurements. Positioning of the hot-spot zones away from the critical percolation path slowed the increase and decline in emission of the gases. The model and its parameters can now be used for modelling the effect of soil compaction and saturation on the emission of nitrous oxide.
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影响因子：
6.3
作者：
Swarthmore College
通讯作者：
Swarthmore College
不锈钢过滤器空隙网络内过滤的深度过滤模型
影响因子：
3.7
作者：
J. C. Price;G. Matthews;K. Quinlan;J. Sexton;A. G. Matthews
通讯作者：
A. G. Matthews
DOI：
--
发表时间：
1991
期刊：
影响因子：
--
作者：
M. Spearing;G. Matthews
通讯作者：
G. Matthews
反硝化作用的瞬时微站点模型：I. 模型开发1
DOI：
--
发表时间：
1985
期刊：
影响因子：
--
作者：
P. Mcconnaughey;D. Bouldin
通讯作者：
D. Bouldin
影响因子：
5.9
作者：
Christian, D. G.;Riche, A. B.;Yates, N. E.
通讯作者：
Yates, N. E.