水稻植株与CH4排放的相关因子及模糊聚类分析

通过对不同水稻品种甲烷排放量与水稻通气组织相关性分析,确定聚类指标,运用离差平方和聚类分析方法对水稻品种进行聚类,初步探讨了水稻植物学特性与甲烷排放的相关性.结果表明,早、晚稻不同水稻品种甲烷排放量与植株显著相关的指标是不同的.早稻品种植株第2节间茎秆维管束总面积、第2节间茎秆壁厚、第2节间叶鞘横切面积/节间横切面积、第2节间叶鞘气腔面积/叶鞘与茎秆横切面积之和4个指标与甲烷排放量呈显著相关关系.晚稻品种植株株高与茎秆长度、第3节间茎壁横切面积/节间横切面积、第3节间茎壁髓腔面积/节间横切面积、第3节间叶鞘横切面积/节间横切面积、第3节间叶鞘维管束面积/节间横切面积、第3节间叶鞘气腔面积/茎壁横切面积、第3节间茎秆维管束面积/茎秆横切面积8个数量指标与甲烷排放量都呈显著相关性.分别以上述相关因子为聚类指标,对早、晚稻品种进行聚类分析,都可分为甲烷排放量高、中、低3类,与实测结果吻合度分别为87.5%和90%.因此,所选指标作为水稻品种甲烷排放量等级聚类指标是可行的,为水稻品种甲烷排放量定性分析提供了实践及理论依据.本研究将为水稻品种甲烷排放量等级区分提供依据,为高产杂交稻、超级稻的育成与推广提供环境学支撑.

Related Factors of Methane Emission in Rice Plant and Fuzzy Cluster Analysis

Different biological characters of rice lead to differences in methane emission of rice cultivars from rice paddy field. The study is to primarily probe the correlation between methane emissions of rice varieties and rice botanical characters, as well as provide the basis for grade distinction of methane emission from cuhivars and the environmental basis for breeding and promoting the high-yielding hybrid rice and super hybrid rice. The cluster indexes are determined and the rice cultivars are clustered using fuzzy cluster analysis, based on the correlations between methane emissions from different rice varieties and rice plant aerenchyma tissues. The results show that the significant correlation factors on methane emission between early and late rice plant are different. For early rice varieties, the significant correlation factors are the total area of stem wall vascular, the thickness of stem wall, the ratio of the transverse section area of leaf sheath to the transverse section area of internode, the ratio of the gas chambers area of leaf sheath to the transverse section area of internode, in the second internode. For late rice, plant height, stem length, the ratio of the vascular bundles area of inside culm to the area of stem wall, the ratio of the stem wall area to the transverse section area of internode, the ratio of the cross section area of leaf sheath to the transverse section area of internode, the ratio of vascular bundles area of leaf sheath to the transverse section area of leaf sheath, the ratio of total vascular bundles area to the stem wall area, the ratio of the gas chambers area of leaf sheath to the stem wall area of third internode, all are very significantly related with methane emissions from rice paddy field. Early or late rice cultivars could be divided into three levels, i.e. high, medium and low amount of methane emission by fuzzy cluster indices above mentioned. Compared the fuzzy cluster results with the test results, the consistent degrees for early and late rice cultivars are 87.5% and 90%, separately. The clustering result is basically consistent with the actual methane emissions of all varieties from rice paddy field. However, the correlation between the root aerenchyma system and methane emission is worth researched in the future since the roots ot rice are the main paths ot methane emission trom paddy tield. Theretore, it is teasible to take the indicators as clustering index on methane emissions of rice cultivars.