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冲积土壤剖面质地层次的垂向变化是一个十分复杂的问题,长期以来都是定性描述而无法定量化。但土壤剖面的质地层次组合特点对土壤水分转化和溶质运移等具有重要影响,对其定量地描述和研究是进一步准确定量区域农田水转化和溶质运移的基础。马尔可夫链理论是用来描述随时间(空间)变化的一个离散状态序列的状态转移特性的,本文将其引入来研究冲积土壤剖面质地层次的垂向变化规律。研究结果表明,区域冲积土壤剖面质地层次的垂向变化具有明显的马氏性,其转移概率矩阵(TPM)具有近似平稳的特点;研究区内土壤质地层次以粘土层为主,其次依次为沙土层、沙壤层、中壤层、轻壤层和重壤层,组合方式以粘-沙、沙-粘,粘-沙-粘和沙-粘-沙为主。
Vertical changes in the texture level of alluvial soil profiles are a complex issue that has long been characterized qualitatively but not quantitatively. However, the characteristics of the soil layer hierarchy have an important influence on the soil moisture conversion and solute transport. Quantitative description and study of the soil profile is the basis for further accurate quantification of water conversion and solute transport in the farmland. Markov chain theory is used to describe the state transition characteristics of a discrete state sequence changing with time (space). This article introduces it to study the vertical variation of the texture level of alluvial soil profile. The results show that the vertical change of texture level in the alluvial soil profile has obvious Markov property, and the transition probability matrix (TPM) has the characteristics of approximate smoothness. The soil texture in the study area is dominated by clay layer, followed by sandy soil Sandy loam, middle loam layer, light loam layer and heavy loam layer. The combination modes are stick-sand, sand-stick, stick-sand-stick and sand-stick-sand.