| 引用本文: | 王志超,李嘉辰,张博文,等.基于CT扫描的微塑料对砂壤土孔隙结构的影响研究[J].灌溉排水学报,0,():-. |
| Wang Zhichao,Li Jiachen,Zhang Bowen,et al.基于CT扫描的微塑料对砂壤土孔隙结构的影响研究[J].灌溉排水学报,0,():-. |
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| 摘要: |
| 【目的】探究微塑料对砂壤土孔隙结构的影响，为土壤新型污染物微塑料的防治提供科学依据，也对应用CT扫描进行土壤结构与土壤质量评估提供借鉴与指导。【方法】采用室内土柱模拟方法和计算机断层扫描技术，对CK（未赋存微塑料的空白组）和M（赋存2%浓度聚丙烯微塑料的试验组）处理进行了三维土壤孔隙结构的可视化分析和孔隙特征参数的测定。【结果】聚丙烯微塑料显著影响砂壤土孔隙结构。通过对三维孔隙结构可视化研究发现，CK处理中土壤孔隙分布较为均匀，出现明显下沉且纵向连续性强，而M处理中土壤孔隙破碎化程度高，连通性较差；且CK处理中土壤孔隙度为4.98%，M处理中土壤孔隙度只有3.79%。聚丙烯微塑料赋存条件下土壤孔隙数量与孔隙体积分布随土壤深度发生变化。在土柱0~4 cm深度范围内，土壤孔隙总数量表现为CK＞M，M处理中土壤孔隙总数较CK处理降低了73.02%，且二者的孔隙数量差异随土壤深度的增加而逐渐增大；土壤平均孔隙体积表现为CK（1 709 mm3）>M（1 235 mm3），且相较于CK处理，M处理的大体积土壤孔隙数量占比有不同程度的降低。聚丙烯微塑料对砂壤土孔隙形态特征产生了影响。随着土层深度的增加，CK处理的孔隙成圆率趋于平稳，孔隙更接近圆形；但孔隙平均当量直径却表现为M > CK，M处理的平均当量直径均随土壤深度的增加呈逐渐上升的趋势。【结论】聚丙烯微塑料的赋存影响了砂壤土孔隙结构并降低了土壤孔隙度，对土壤孔隙数量和形态特征也产生了一定的影响。 |
| 关键词: 计算机断层扫描技术;微塑料;土壤孔隙结构;三维可视化 |
| DOI： |
| 分类号:S152.7 |
| 基金项目:国家自然科学基金项目（面上项目，重点项目，重大项目） |
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| Effect of microplastics on the pore structure of sandy loam soil based on CT scanning |
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Wang Zhichao, Li Jiachen, Zhang Bowen, Jing Shuangyi, Li Weiping
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Inner Mongolia University of Science and Technology
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| Abstract: |
| 【Background】Microplastics, an emerging pollutant, has become an important environmental issue of general concern worldwide. Microplastic pollution as a "source" of microplastics in the water environment and a "sink" for terrestrial microplastics is also receiving increasing attention from scholars, especially the research on soil microplastic pollution is imminent in recent years. 【Objective】To investigate the effect of microplastics on the pore structure of sandy loam soils, to provide scientific basis for the prevention and control of new soil contaminants microplastics, and to provide reference and guidance for soil structure and soil quality assessment by CT scanning.【Methods】The visualization of soil pore structure and the determination of pore characteristics parameters were carried out in CK (blank group without microplastics) and M (experimental group with 2% polypropylene microplastics) treatments using indoor soil column simulation and computed tomography.【Result】Polypropylene microplastics significantly affected the pore structure of sandy loam soils. The visualization of the three-dimensional pore structure revealed that the soil pores in the CK treatment were more uniformly distributed, with significant sinking and longitudinal continuity, while the soil pores in the M treatment were highly fragmented and less connected; and the soil porosity was 4.98% in the CK treatment and only 3.79% in the M treatment. The number of soil pores and pore volume distribution changed with soil depth under the conditions of polypropylene microplastic fugacity. In the depth range of 0-4 cm, the total number of soil pores was CK > M. The total number of soil pores in the M treatment was 73.02% lower than that in the CK treatment, and the difference in the number of pores between them gradually increased with the increase of soil depth; the average volume of soil pores was CK (1709 mm3) > M (1235 mm3), and compared with the CK treatment, the large volume of the M treatment compared with the CK treatment, the large volume of soil pore volume in the M treatment had different degrees of reduction. Polypropylene microplastics influenced the pore morphological characteristics of sandy loam soils. With the increase of soil depth, the pore rounding rate of CK treatment tended to be stable and the pores were closer to round; however, the average equivalent diameter of pores showed that M > CK, and the average equivalent diameter of M treatment all showed a gradually increasing trend with the increase of soil depth. 【Conclusion】The deposition of polypropylene microplastics affected the pore structure and reduced the soil porosity of sandy loam soils, and also had an effect on the number and morphological characteristics of soil pores. |
| Key words: computed tomography technique; microplastics; soil pore structure; three-dimensional visualization |
