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题名	侵蚀产沙研究的土壤颗粒分析方法对比
作者	阎丹丹
学位类别	硕士
答辩日期	2015
授予单位	中国科学院研究生院
授予地点	北京
导师	贺秀斌
关键词	侵蚀产沙 紫色土 颗粒分析 前处理
其他题名	Methodological Comparison of Soil Particle-size Analysis in View of Sedimentation Process
学位专业	土壤学
中文摘要	颗粒组成是土壤学和侵蚀产沙研究中重要的基础数据。土壤学研究中颗粒分析的目的是为了了解土壤质地、保水性、保肥性等信息，其研究对象为土壤单粒；土壤侵蚀和泥沙输移研究中颗粒分析的目的是了解泥沙侵蚀输移过程，其研究对象是泥沙输移过程中的有效粒径。现有的颗粒分析前处理方法较多，测定方法主要有吸管法和激光粒度仪法两种。紫色土作为新成土，其中包含了团聚体、岩屑和单粒等复杂的粒度组成，不同的前处理方法和分析方法，都会对其分析结果造成影响，并且对紫色土颗粒分析方法的研究还少有报道。为了明确前处理和测定方法对紫色土颗粒组成测定结果的影响，以及侵蚀产沙过程研究的颗粒分析前处理方法和侵蚀产沙过程的颗粒组成特性，本文以原状紫色土、沟垄耕作沟道沉积泥沙及重庆忠县石宝镇长江消落带沉积泥沙为研究对象，采用不同的前处理和测定方法分析同一样品的粒径组成，将结果进行对比，探讨了适合土壤侵蚀与泥沙输移研究的颗粒分析方法，并提出了针对紫色土的激光粒度仪法与吸管法测定结果的转换公式。论文主要研究结论如下： （1）振荡对土壤样品和短距离搬运沉积泥沙有明显的分散作用，但对消落带沉积泥沙分散作用较小。双氧水处理对不同类型样品颗粒组成影响不同，原因可能是样品有机质含量和有机质存在形式的差异；消落带沉积泥沙在长距离搬运过程中，其土壤原始结构被破坏，因此对盐酸和双氧水的处理都较为敏感。六偏磷酸钠对未经双氧水和盐酸处理的样品有较好的分散作用。总的来看，前处理方法对样品的粒度测量结果有较大的影响，且处理效果受到样品特性的影响；全部样品中值粒径绝对变化和相对变化为20.7-127.2μm和94.2-1467.1%，同一系列样品中值粒径的变化虽然也存在差异，但差异较小；不同前处理方法处理得到的粒度有明显差异，但系列样品在不同前处理下的中值粒径变化趋势具有高度相似性。 （2）经短距离搬运的沉积泥沙与土壤对前处理方法的敏感程度没有明显差异，但是消落带沉积泥沙与土壤对前处理方法的敏感程度有明显的差异。土壤和经短距离搬运的沉积泥沙在纯物理振荡下就能得到最小的中值粒径，而消落带沉积泥沙需要经过化学处理才能得到最小中值粒径；侵蚀泥沙并不完全以单粒的形式存在，而是包含着团聚结构，并且化学方法处理会破坏泥沙中的团聚结构。用物理方法进行前处理所测得的有效颗粒组成适用于侵蚀产沙过程的研究，而终极颗粒组成的前处理方法则需根据样品的性质合理选择。 （3）激光法测得的粘、粉、砂粒平均含量分别为吸管法测得的41.37%、147.84%和67.38%。吸管法和激光法测得的砂粒、粉粒和粘粒含量均差异显著，但是都具有显著的相关性，砂粒、粉粒和粘粒的相关系数分别为：0.9305、0.8951和0.6046（P<0.001）。吸管法和激光法测定结果的转换公式为——砂粒：y吸管砂= 0.9763x 激光砂+ 15.842，粉粒：y吸管粉= 0.9881x激光粉 -20.164，粘粒 y转化粘= 100- (y吸管砂+ y吸管粉)。在美国农部制砂土、壤土和粘土三级分类下，根据转换公式转换后的质地与吸管法测定的质地完全一致。
英文摘要	Particle size distribution is the basic data for soil science and erosion and sediment yield research. The purpose of particle size analysis in soil science is to get the information of soil classification，soil texture, nutrient preserving capability, and the object of study is primary particles; The purpose of particle size analysis in sediment transport is to understand sediment transport process, and the object of study is effective particles. Several pretreatment methods have been used by researchers, both pipette method and lazer diffraction method can be used to measure particle size distribution. As a entisol, purple soil contain aggregrate, rock waste, primary particle, different pretreatments and measuring methods may have different effects on analysis result, but there is few research on particle size analysis for purple soil. To realize the effect of pretreatment and measuring method on particle size distribution of purple soil, purple soil, sediment deposited in furrow and water level fluctuating zone were sampled for the study to analyze the particle size distribution influenced by pretreatments and measuring methods; the study further discusses the appropriate pretreatments selection for soil erosion and sediment transport research；and propose the conversion equations of data for purple soil between pipette method and laser diffraction method.The following principal conclusions were obtained: （1）Vibration has the best dispersion effect on soil and sediment that has been eroded nearby, but has less effect on sediment of water level fluctuating zone; different sample types have different organic content and different kind of origanic matter, so hydrogen peroxide has different effect on paticle size distribution of samples; Sediment deposited in water level fluctuating zone is sensitivity to hydrogen peroxide and hydrochloric acid pretreatments; sodium hexametaphosphate has the good dispersion effect on samples without pretreatment hydrochloric acid and hydrogen peroxide. All in all, pretreament has obvious effect on particle size distribution of samples, and the effvct is based on properties of samples. the absolute and relative change of median size of all samples are 0.7-127.2μand 94.2-1467.1% respectively, median size change of the same type samples are also different, but discrepancy is low; particle size distribution got after different pretreaments are different, but the median size variation tendency of sample series get the high similarities under different pretreatment. （2）Sediment deposited in furrow(eroded nearby) and soil have the same level of sensitivity to pretreatments, while sediment deposited water level fluctuating zone and soil have differnent sensitivity level to pretreatments. Purple soil and sediment from furrow get the best dispersion effect and the minimum median diameter by shaking, while sediment from water level fluctuating zone get the best dispersion effect and the minimum median diameter by chemical pretreatment; significant mode of sediment transport is in form of aggregates and chemical pretreatment can disperse these aggregates. Non-chemical pretreatment are the appropriate treatment for soil erosion and sediment transport study deriving effective particle size distribution, while pretreatment for ultimate particle size distribution should be chosen according to the properties of samples. （3）Clay, silt and sand contents measured by lazer diffraction method is 41.37%, 147.84% and 67.38% of what pipette method measured. Clay, silt and sand content measured by lazer method and pipette method are significantly different, but significant relationships were found between the clay, silt and sand contents determined by the two different methods, the correlation coefficient of clay, silt and sand contents are 0.9305、0.8951and 0.6046（P<0.001） respectively. The conversion equations of clay, silt and sand contents between lazer diffraction method and pipette method are as follows: sand：yp
语种	中文
内容类型	学位论文
源URL	[http://ir.imde.ac.cn/handle/131551/14129]
专题	成都山地灾害与环境研究所_山地表生过程与生态调控重点实验室
作者单位	中国科学院成都山地灾害与环境研究所
推荐引用方式 GB/T 7714	阎丹丹. 侵蚀产沙研究的土壤颗粒分析方法对比[D]. 北京. 中国科学院研究生院. 2015.

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