中国东北黑土区冻融循环与初始土壤含水量对土壤抗剪强度的影响

发布时间：2021-05-09 16:13

　　季节性冻融循和不同初始土壤含水量对土壤剪切应力有重要影响,其进而影响坡面水蚀过程;然而目前冻融循环对坡面水蚀过程机理的影响研究还不十分清楚,特别是冻融循环对东北黑土区农地土壤抗侵蚀能力的影响研究还相对薄弱。因此,本研究以黑龙江省黑土区的克山县（KS）和宾县（BX）为研究区,通过设计5个冻融循环次数（0、1、3、5和7次）、3个初始土壤含水量（16.5%、24.8%和33.0%）和2种试验土壤处理（扰动土和原状土）和采用土壤直剪试验,研究了冻融循环次数和土壤初始含水量对土壤剪切应力的影响,研究结果加深了对冻融作用影响坡面土壤侵蚀机理的认识,同时也为黑土区侵蚀防治提供了科学依据。主要研究结论如下:（1）土壤剪切应力和土壤粘聚力皆随冻融循环次数和前期土壤含水量的增加而减少。当冻融循环从0次增加到7次,BX和KS土壤剪切应力分别降低8.6%¹8.0%和13.1%¹8.0%。当前期土壤含水量分别为16.5%、24.8%和33.0%,5次冻融循环使BX土壤粘聚力分别减少70.9%、71.1%和65.9%和KS土壤粘聚力分别减少56.6%、61.7%and... 

【文章来源】：西北农林科技大学陕西省 211工程院校 985工程院校 教育部直属院校

【文章页数】：63 页

【学位级别】：硕士

【文章目录】：
ABSTRACT
摘要
CHAPTER 1 INTRODUCTION
    1.1 Background
    1.2 Research significances
    1.3 Literature review
        1.3.1 The distribution of mollisol
        1.3.2 Freeze-thaw effects
        1.3.3 Effects of freeze-thaw cycle on soil structure
        1.3.4 Effect of initial soil water content on soil shear strength
        1.3.5 Measurement of soil shear strength
CHAPTER 2 RESEARCH CONTENTS AND METHODS
    2.1 Objectives
    2.2 Research contents
        2.2.1 Effects of freeze-thaw cycles on soil shear stress
        2.2.2 Effects of initial soil water content on soil shear stress
        2.2.3 Comparison of soil shear stress between remolded and undisturbed soils
    2.3 Research methods
        2.3.1 Study area
        2.3.2 Experimental design
        2.3.3 Direct shear test
        2.3.4 Soil sampling processes
        2.3.5 Technical route
    2.4 Data analysis and calculating method
        2.4.1 Data analysis
        2.4.2 Calculating method
CHAPTER 3 EFFECTS OF FREEZE-THAW CYCLES ON SOIL SHEAR STRESS
    3.1 Introduction
    3.2 Material and method
    3.3 Results and discussion
    3.4 Conclusion
CHAPTER 4 EFFECTS OF INITIAL SOIL WATER CONTENT ON SOIL SHEAR STRESS
    4.1 Introduction
    4.2 Materials and method
    4.3 Results and discussion
    4.4 Conclusion
CHAPTER 5 COMPARISONS OF SHEAR STRESS BETWEEN REMOLDED AND UNDISTURBED SOILS
    5.1 Introduction
    5.2 Material and method
    5.3 Results and discussion
    5.4 Conclusion
CHAPTER 6 CONCLUSIONS AND PERSPECTIVES
    6.1 Main conclusions
    6.2 Perspectives
REFERENCES
ACKNOWLEDGEMENTS
BIOGRAPHY


【参考文献】：
期刊论文
[1]Effects20of20Freeze–thaw20Cycles20on20Soil20Mechanical20and20Physical20Properties20in20the20Qinghai–Tibet20Plateau[J]. XIE Sheng-bo,QU Jian-jun,LAI Yuan-ming,ZHOU Zhi-wei,XU Xiang-tian.  Journal of Mountain Science. 2015(04)
[2]基于RClimDex模型的江西省极端降水时空变化研究[J]. 陈昌春,张余庆,王腊春,闫铁柱,宋洁.  中国农村水利水电. 2013(11)
[3]冻融循环对含盐土物理力学性质影响的试验研究[J]. 邴慧,何平.  岩土工程学报. 2009(12)
[4]桂东南地区马尾松工程幼林郁闭过程的生态环境变化特征[J]. 黄承标,梁宏温.  应用与环境生物学报. 1999(06)



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