摘 要

生物质炭的输入被认为是降低土壤CO₂排放以应对全球气候变化的重要措施之一。本研究以人工榉树林土壤为研究对象，以水稻为原料分别在300和500 ºC下制备两种生物质炭，研究了生物质炭输入（CK、B300和B500）对榉树林土壤CO₂排放的影响，并探讨了土壤CO₂排放与土壤温度、水分之间的关系。生物质炭施用103-166 d期间，CK、B300和B500三个处理的CO₂排放通量呈现相似的时间动态，即前期呈现不断增加趋势，后期呈现先降低后升高的变化趋势，平均值分别为25.5、35.8和17.8 mg C m^-2 h^-1。相关分析表明，三个处理的土壤CO₂排放通量与土壤温度、水分均不存在显著相关性。实验期间，CK、B300和B500处理的CO₂累积排放量分别为27.5、38.5和54.2 g C m^-2，CK和B300处理以及CK和B500处理的差异均达到显著水平（p lt; 0.05）。因此，低温（300 ºC）和高温（500 ºC）制备的生物质炭分别提高和降低了人工榉树林土壤CO₂的排放。

关键词：生物质炭；CO₂通量；土壤温度；人工林土壤；累积排放量

Effects of Biochar on CO₂ Emission from a Plantation Soil

ABSTRACT

The input of biochar is considered to be one of the important measures to reduce soil CO₂ emissions in response to global climate change. In this study, two kinds of biochar were prepared at 300 and 500 ºC by using rice as raw material, and the effects of biochar amendment (CK, B300 and B500) on soil CO₂ emission from Zelkova schneideriana plantation, and the relationships between soil CO₂ emission and soil temperature and water were studied. After biochar amendment 103-166 d, the CO₂ effluxes from CK, B300 and B500 treatments showed similar trends, that is, the increasing trend during early period while the trend of first decreasing then increasing during later period, with the average CO₂ effluxes 25.5, 35.8 and 17.8 mg C m^-2 h^-1, respectively. The correlation analysis showed that there was no significant correlations between soil CO₂ flux and soil temperature and water. During the experiment, CO₂ emissions from CK, B300 and B500 were 27.5, 38.5 and 54.2 g C m^-2, respectively, and the differences were significant (p lt;0.05). Thus, biochar at low temperature (300 ºC) and high temperature (500 ºC) could increase and decrease soil CO₂ emissions from Zelkova schneideriana plantation, respectively.

Key words：Biochar；CO₂ efflux；Soil temperature；Plantation soil；Cumulative emission

目 录

1. 文献综述…………………………………………………………………………………………………1

1.1 生物质炭及其性质………………………………………………………………………………1

1.1.1 生物质炭……………………………………………………………………………………1

1.1.2 生物质炭性质………………………………………………………………………………1

1.2 生物质炭对土壤理化性质的影响……………………………………………………………1 1.3 生物质炭对土壤CO₂排放的影响…………………………………………………………… 2

1.4 生物质炭影响土壤CO₂排放的机制………………………………………………………… … 3

2 研究背景、内容与技术路线……………………………………………………………………………4

2.1 研究背景…………………………………………………………………………………………4

2.2 研究内容…………………………………………………………………………………………4

2.3 技术路线…………………………………………………………………………………………5

3 材料与方法………………………………………………………………………………………………6

3.1 研究区概况………………………………………………………………………………………6

3.2 生物质炭的制备和基本性质……………………………………………………………………6

3.3 实验设计…………………………………………………………………………………………7

3.4 样品采集…………………………………………………………………………………………7

3.5 数据计算…………………………………………………………………………………………8

3.6 数据分析…………………………………………………………………………………………9

4 人工林土壤CO₂排放通量的时间动态………………………………………………………………10

4.1 土壤温度和水分动态……………………………………………………………………………10

4.2 土壤CO₂排放通量的时间动态…………………………………………………………… 11

4.3 讨论………………………………………………………………………………………12

4.4 小结………………………………………………………………………………………12

5 生物质炭对人工林土壤CO₂排放的影响……………………………………………………………13

5.1 生物质炭对土壤CO₂排放通量的影响…………………………………………………………13

5.2 生物质炭对土壤CO₂累积排放量的影响…………………………………………………… 13

5.3 讨论………………………………………………………………………………………14

5.4 小结………………………………………………………………………………………15

6 全文结论和展望……………………………………………………………………………………… 16

6.1 全文结论…………………………………………………………………………………………16

6.2 展望………………………………………………………………………………………………16

致谢 ………………………………………………………………………………………………………17

参考文献……………………………………………………………………………………………………18

1 文献综述

1.1 生物质炭及其性质

1.1.1 生物质炭

生物质（秸秆和枯枝落叶等）开发利用是永久而不竭的主题，最早可追溯至西周时期。生物质炭是近几年国际上出现的新名词。在厌氧或者绝氧的条件下对生物质进行热解，除生成CO₂、可燃性气体、挥发性油类和焦油类物质，还产生含碳丰富的固体物质，一般称之为生物质炭（Sohi等，2010；Zhang等，2010）。生物质炭作为良好的固碳剂，是解决全球变暖的一种新方法，引起了国内外学者的关注。

1.1.2 生物质炭的性质