Effect of Rice Plants on Methane Emission from Paddy Fields and Its Biological Mechanism: A Review

doi:10.11924/j.issn.1000-6850.casb2022-0143

Abstract

Abstract:

Paddy fields are one of the main sources of agricultural methane emissions and have important impacts on global greenhouse gas emissions. Methane emission from paddy fields includes three processes: the methane production by soil methanogens, the methane oxidation by aerobic methane-oxidizing bacteria, and the methane emission through the three approaches (rice plants, bubbling and diffusion in soil solution). Both the aboveground parts and root systems of rice plants affect the methane emission in paddy fields. This paper briefly introduced the production, oxidation and transport of methane from paddy fields, and summarized effects of the root characteristics (morphological characteristic, root aerenchyma, root exudates and oxygen secretion), the characteristics of aboveground parts (plant height, tiller number, biomass and assimilates’ distribution) and the water and fertilizer management on the methane emission from paddy fields, and the underlying mechanisms were also reviewed. The main future research area of paddy methane emission was discussed, and attention should be paid to the coordination of high grain yield and low methane emission.

Key words: paddy fields, methane emission, root exudates, distribution of assimilates, aerenchyma

REN Xiaojian, PENG Yuxuan, HAN Kaiyan, DENG Zhiming, CUI Kehui. Effect of Rice Plants on Methane Emission from Paddy Fields and Its Biological Mechanism: A Review[J]. Chinese Agricultural Science Bulletin, 2022, 38(36): 80-87.

Figures/Tables 3

References 94

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植株特征	对甲烷排放的影响	参考文献
根生物量	甲烷排放与根生物量正相关	[39⇓-41]
根生物量	孕穗期甲烷排放与根系生物量负相关，籼型超级稻较低的根系生物量导致其甲烷排放量显著高于粳型超级稻	[45⇓-47]
根条数	根条数促进稻田土壤的甲烷传输速率	[40]
根体积	甲烷排放与根体积正相关	[41,49-50]
根长	根系越长，甲烷排放通量越大	[39,50]
根长	孕穗期甲烷排放通量与根长呈负相关关系	[46-47]
根系通气组织	根系通气组织越发达甲烷排放越低，两者之间呈显著负相关	[51-52]
根系通气组织	土壤氧化还原电位降低促进水稻根系通气组织形成，促进甲烷产生和排放	[39]
根系分泌物	根系分泌物中有机酸和有机碳等能够促进稻田甲烷的产生和排放	[12,52-53]
根系分泌物	根系分泌物中的苹果酸、琥珀酸、柠檬酸能增强稻田甲烷氧化菌的丰度和活性，降低甲烷排放	[47,54]
根系泌氧能力	根系泌氧能力弱的水稻突变体材料，稻田甲烷排放增强，稻田甲烷排放与根系泌氧能力显著负相关	[47-48,51]

植株特征	对甲烷排放的影响	参考文献
根生物量	甲烷排放与根生物量正相关	[39⇓-41]
根生物量	孕穗期甲烷排放与根系生物量负相关，籼型超级稻较低的根系生物量导致其甲烷排放量显著高于粳型超级稻	[45⇓-47]
根条数	根条数促进稻田土壤的甲烷传输速率	[40]
根体积	甲烷排放与根体积正相关	[41,49-50]
根长	根系越长，甲烷排放通量越大	[39,50]
根长	孕穗期甲烷排放通量与根长呈负相关关系	[46-47]
根系通气组织	根系通气组织越发达甲烷排放越低，两者之间呈显著负相关	[51-52]
根系通气组织	土壤氧化还原电位降低促进水稻根系通气组织形成，促进甲烷产生和排放	[39]
根系分泌物	根系分泌物中有机酸和有机碳等能够促进稻田甲烷的产生和排放	[12,52-53]
根系分泌物	根系分泌物中的苹果酸、琥珀酸、柠檬酸能增强稻田甲烷氧化菌的丰度和活性，降低甲烷排放	[47,54]
根系泌氧能力	根系泌氧能力弱的水稻突变体材料，稻田甲烷排放增强，稻田甲烷排放与根系泌氧能力显著负相关	[47-48,51]

植株特征	对甲烷排放的影响	参考文献
植株高度	植株较高的水稻品种稻田甲烷排放较高，与稻田甲烷排放显著正相关	[45,62,64-65]
	与稻田甲烷排放没有显著相关性	[13,66 -67]
	籼型超级稻品种稻田甲烷排放量与株高显著负相关，而粳型品种为正相关	[45]
分蘖数	与分蘖数显著正相关	[63]
分蘖数	与分蘖数无显著相关性	[13,66]
地上部生物量	与地上部植株生物量显著正相关	[68]
	与地上部生物量无显著相关性	[13,67]
	稻田甲烷排放与地上部生物量呈著负相关，生物量高的品种甲烷排放相对较低	[52,69]
光合产物分配	减少光合产物向根系分配、增强其向穗部分配，可以降低稻田甲烷排放	[70-71]
光合产物分配	向根系分配较多的光合产物可以促进根系生长，降低稻田甲烷的产生	[47]

植株特征	对甲烷排放的影响	参考文献
植株高度	植株较高的水稻品种稻田甲烷排放较高，与稻田甲烷排放显著正相关	[45,62,64-65]
	与稻田甲烷排放没有显著相关性	[13,66 -67]
	籼型超级稻品种稻田甲烷排放量与株高显著负相关，而粳型品种为正相关	[45]
分蘖数	与分蘖数显著正相关	[63]
分蘖数	与分蘖数无显著相关性	[13,66]
地上部生物量	与地上部植株生物量显著正相关	[68]
	与地上部生物量无显著相关性	[13,67]
	稻田甲烷排放与地上部生物量呈著负相关，生物量高的品种甲烷排放相对较低	[52,69]
光合产物分配	减少光合产物向根系分配、增强其向穗部分配，可以降低稻田甲烷排放	[70-71]
光合产物分配	向根系分配较多的光合产物可以促进根系生长，降低稻田甲烷的产生	[47]