江汉平原双层结构包气带渗透系数不确定性对氨氮运移的影响

喻静; 裴洪军; 汪丙国

doi:10.19509/j.cnki.dzkq.tb20230722

江汉平原双层结构包气带渗透系数不确定性对氨氮运移的影响

doi: 10.19509/j.cnki.dzkq.tb20230722

喻静^1,,
裴洪军²,
汪丙国^1, ,

1 .
中国地质大学（武汉）环境学院，武汉 430078
2 .
深圳市水务规划设计院股份有限公司，广东深圳 518000

基金项目: 国家自然科学基金项目（41772268）；国家重点研发计划项目子课题（2022YFC3702401）

详细信息

作者简介:
喻静：E-mail：yujing9000@163.com

通讯作者:
E-mail：bgwang@cug.edu.cn

中图分类号: P641
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- 文章访问数: 114
- PDF下载量: 3
- 被引次数: 0
出版历程
- 收稿日期: 2024-01-02
- 录用日期: 2024-05-06
- 修回日期: 2024-04-29
- 网络出版日期: 2025-10-17

Influence of saturated hydraulic conductivity uncertainty on ammonium-nitrogen transport in the double-layer vadose zone of the Jianghan Plain

YU Jing^1
,,
PEI Hongjun²,
WANG Bingguo^{1
, ,}

1 .
School of Environmental Studies, China University of Geosciences(Wuhan), Wuhan 430078, China
2 .
Shenzhen Water Planning & Amp, Design Institute Co., Ltd., Shenzhen Guangdong 518000, China

More Information

Author Bio:
E-mail：yujing9000@163.com

Corresponding author: E-mail：bgwang@cug.edu.cn

摘要

摘要:
为探究双层结构包气带饱和渗透系数不确定性对溶质运移的影响，采用数值模拟方法开展了江汉平原典型双层结构包气带饱和渗透系数不确定性对氨氮运移影响的随机模拟。结果表明，考虑上层土壤饱和渗透系数不确定性时，“上粗下细”型岩性结构的氨氮锋面运移深度、质量浓度峰值和质量浓度峰值深度及其变化幅度均大于“上细下粗”型。考虑下层土壤饱和渗透系数不确定性时，氨氮锋面运移深度、运移质量浓度峰值和质量浓度峰值深度3种指标在“上粗下细”型岩性结构中受饱和渗透系数不确定性影响均较小，而在“上细下粗”型岩性结构中受到的影响相对较大。对比上层和下层土壤饱和渗透系数不确定性的模拟结果可知，砂壤土饱和渗透系数不确定性对氨氮质量浓度峰值及其深度的影响均大于粉砂壤土。由此推论：双层结构包气带中，粗质土壤的饱和渗透系数不确定性对溶质运移的影响更大。研究结果可为江汉平原地区开展包气带溶质运移研究提供方法参考，为江汉平原地下水氨氮污染防治工作提供科学依据。
- 土壤饱和渗透系数 /
- 不确定性 /
- 双层结构 /
- 氨氮运移 /
- 数值模拟 /
- 包气带 /
- 江汉平原
Abstract: Objective
To investigate the influence of uncertainty in soil saturated hydraulic conductivity on solute transport,
Methods
stochastic numerical simulations were conducted to examine the effects of saturated hydraulic conductivity uncertainty on ammonium-nitrogen (NH₄⁺-N) transport within a representative double-layer vadose zone of the Jianghan Plain.
Results
The results show that, when considering the uncertainty of the saturated hydraulic conductivity of the upper soil, the migration depth of the NH₄⁺-N front, the peak concentration, and the depth of the concentration peak-along with their variation ranges, are all greater in the "coarse on top and fine on bottom" lithologic configuration than in the "fine on top and coarse on bottom" configuration. When considering the uncertainty of the saturated hydraulic conductivity of the lower soil, these three indicators are less sensitive to conductivity uncertainty in the "coarse-upper and fine-lower" structure, whereas the impacts are relatively more significant in the "fine-upper and coarse-lower" structure. Comparison of the simulation results indicates that the uncertainty of saturated hydraulic conductivity in sandy loam exerts a stronger influence on the magnitude and depth of NH₄⁺-N concentration peaks than that in silty loam. This suggests that, within double-layer vadose zones, the uncertainty of saturated hydraulic conductivity in coarse-textured soils plays a more significant role in controlling solute transport.
Conclusion
The findings provide a methodological reference for vadose-zone solute transport research in the Jianghan Plain and a scientific basis for the prevention and control of groundwater NH₄⁺-N pollution in the region.
- soil saturated hydraulic conductivity /
- uncertainty /
- double-layer structure /
- ammonium-nitrogen transport /
- numerical simulation /
- vadose zone /
- Jianghan Plain

HTML全文

图 1 模拟结束时（第60 d）氨氮的质量浓度分布

Figure 1. Distribution of ammonium-nitrogen (NH₄⁺-N) concentration at the end of simulation (Day 60)

下载: 全尺寸图片幻灯片

图 2 上层土壤饱和渗透系数（K_s）不确定性条件下模拟的氨氮锋面运移深度与K_s的关系图（SL-SiL. “上粗下细”型；SiL-SL. “上细下粗”型；K_s. 饱和渗透系数；下同）

Figure 2. Relationship between simulated ammonium-nitrogen front migration depth and saturated hydraulic conductivity (K_s) under the uncertainty of upper soil K_s

下载: 全尺寸图片幻灯片

图 3 上层土壤饱和渗透系数（K_s）不确定性条件下模拟第60 d的氨氮运移质量浓度峰值（a）和质量浓度峰值深度（b）与K_s的关系图

Figure 3. Relationships between peak ammonium-nitrogen concentration (a) and depth of peak ammonium-nitrogen concentration (b) and saturated hydraulic conductivity (K_s) on Day 60 of simulation under the uncertainty of upper soil K_s

下载: 全尺寸图片幻灯片

图 4 上层土壤饱和渗透系数（K_s）不确定条件下的模拟第 60 d 氨氮质量浓度峰值（a）和质量浓度峰值深度（b）箱形图

IQR. 四分位距，表示数据中间50 %的分布范围，即从25%（Q1，下四分位)到75%(Q3，上四分位），1.5IQR. 上须通常取Q3+1.5×IQRQ3+1.5×IQR内的最大值，下须通常取Q1−1.5×IQRQ1−1.5×IQR 内的最小值, 超出这个范围的点会被认为是离群值，下同

Figure 4. Box plots of peak ammonium-nitrogen concentration (a) and depth of peak ammonium-nitrogen concentration (b) on Day 60 of simulation under the uncertainty of upper soil saturated hydraulic conductivity (K_s)

下载: 全尺寸图片幻灯片

图 5 下层土壤饱和渗透系数（K_s）不确定性条件下模拟的氨氮锋面运移深度与K_s的关系图

Figure 5. Relationship between simulated ammonium-nitrogen front migration depth and saturated hydraulic conductivity (K_s) under the uncertainty of lower soil K_s

下载: 全尺寸图片幻灯片

图 6 下层土壤饱和渗透系数（K_s）不确定性条件下模拟第 60 d 的氨氮质量浓度峰值（a）和质量浓度峰值深度（b）与 K_s 的关系图

Figure 6. Relationships between peak ammonium-nitrogen concentration (a) and depth of peak ammonium-nitrogen concentration (b) and saturated hydraulic conductivity (K_s) on Day 60 of simulation under the uncertainty of lower soil K_s

下载: 全尺寸图片幻灯片

图 7 下层土壤饱和渗透系数（K_s）不确定性条件下的模拟第 60 d 氨氮质量浓度峰值（a）和质量浓度峰值深度（b）箱形图

Figure 7. Box plots of peak ammonium-nitrogen concentration (a) and depth of peak ammonium-nitrogen concentration (b) on Day 60 of simulation under the uncertainty of lower soil saturated hydraulic conductivity (K_s)

下载: 全尺寸图片幻灯片

表 1 2种岩性土壤饱和渗透系数随机数的描述性统计

Table 1. Descriptive statistics of random number of saturated hydraulic conductivity for two lithologic soils

岩性	随机数/组	饱和渗透系数K_s/(cm·d⁻¹)				变异系数CV/%
岩性	随机数/组	最大值	最小值	平均值	标准差	变异系数CV/%
砂壤土	148	259.07	0.5614	15.70	29.89	190.38
粉砂壤土	148	155.50	0.0046	4.07	13.74	337.59
注：变异系数(CV)=标准差/平均值

下载: 导出CSV

表 2 土壤水力参数

Table 2. Soil hydraulic parameters

岩性	饱和含水率 $ \theta_{\mathrm{s}} $/(cm³·cm⁻³)	残余含水率 $ \theta_{\mathrm{r}} $/(cm³·cm⁻³)	经验参数 α/cm⁻¹	经验参数 n	经验参数 l
砂壤土	0.41	0.065	0.075	1.89	0.5
粉砂壤土	0.45	0.067	0.02	1.23	0.5

下载: 导出CSV

表 3 溶质运移参数

Table 3. Solute transport parameters

岩性	纵向弥散度 D_L^[21]/cm	吸附等温系数K_d^[22]/ (cm³·mg⁻¹)	自由水中分子扩散系数D_w^[23]/ (cm²·d⁻¹)	溶解相一级速率常数 Sinkwater1^[24]	固相一级速率常数 Sinksolid1^[24]
粉砂壤土	7.4	0.030	4	0.2	0.005
砂壤土	15.6	0.015	4	0.1	0.005

下载: 导出CSV

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