增温对冬小麦秸秆及根系分解特性的影响

论文总字数：17794字

目 录

摘要 I

Abstract II

引言 1

1实验与方法 2

1.1取样地点情况介绍 2

1.2试验设计 2

1.2.1田间的增温处理 2

1.2.2冬小麦秸秆及根系的样品采集 2

1.2.3土壤样品采集 3

1.2.4预培养 3

1.3土壤呼吸速率测定 3

1.3.1测定方法 3

1.3.2数据处理方法 3

1.4测定土壤的酶活性 4

1.4.1土壤脲酶活性 4

1.4.2土壤转化酶活性 4

1.4.3土壤过氧化氢酶活性 5

1.5土壤DOC含量的测定 5

1.6土壤pH的测定 6

1.7数据分析 6

2结果与分析 6

2.1增温对冬小麦秸秆及根系分解特性的影响 6

2.2不同处理后冬小麦秸秆或根系的分解系数 7

2.3影响冬小麦秸秆及根系分解特性的内在机制 8

2.3.1增温对冬小麦秸秆及根系分解后土壤中脲酶活性的影响 8

2.3.2增温对冬小麦秸秆及根系分解后土壤中转化酶活性的影响 9

2.3.3增温对冬小麦秸秆及根系分解后土壤中过氧化氢酶活性的影响 10

2.3.4增温对冬小麦秸秆及根系分解后土壤中DOC含量活性的影响 10

2.3.5增温对冬小麦秸秆及根系分解后土壤pH值的影响 11

2.4土壤CO₂排放量和酶活性、DOC含量、pH值的关系分析 11

2.5过氧化氢酶和pH值与土壤CO₂排放量的关系 14

3讨论 15

3.1增温后冬小麦秸秆及根系分解累积CO₂排放量的变化 15

3.2增温后冬小麦秸秆及根系分解土壤酶活性、DOC含量、pH值的变化 15

3.3土壤酶活性、DOC含量、pH值和冬小麦秸秆及根系分解系数与土壤CO₂排放量的关系 16

4结论 16

参考文献 16

致谢 18

增温对冬小麦秸秆及根系分解特性的影响

蒋昊

，China

Abstract：We set up a test for increasing temperature and control treatment in the field to study the effect of warming on the decomposition characteristics of straw and root system of winter wheat. And we observed the decomposition of winter wheat roots and straw and measured the respiration rate of the soil through a portable soil CO₂ emission measurement system. We also measured urease activity, invertase activity, catalase activity, DOC, and soil pH in the soil. The results of the experiment can be seen that after warming treatment, the accumulated CO2 in straw or roots of winter wheat was significantly higher than that of the control group. This shows that by increasing the temperature, the winter wheat straw or root system has a very significant increase in soil CO₂ emissions during the decomposition process. At the same time, the decomposition coefficient of winter wheat straw or roots after warming treatment was significantly higher than that of the control group. Warming has a certain role in promoting the cumulative CO2 emissions from decomposition of winter wheat straw and roots Soil CO₂ emissions are also related to enzyme activity and will increase in logarithmic form with increasing enzyme activity. The activity of various enzymes in soil can be used as an indicator to evaluate the decomposition characteristics of straw and root system in winter wheat and soil CO₂ emission. Soluble organic carbon in the soil also has a certain relationship with soil CO2 emissions. The content of soluble organic carbon in the soil of winter wheat straw after warming treatment is obviously less than that of the control, but the root system is higher than the control.

Key words：warming; straw and root decomposition; CO₂ emissions; Enzyme activity; DOC

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