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用箱式法在太原盆地对冬小麦的碳通量进行了两年的测定,对比分析了气温(T_a)、土壤温度(T_s)和冠层辐射温度(T_c)的日、季节变化与冬小麦碳通量日、季节变化的关系.结果表明,在日、季节尺度上T_c与T_a具有较好的一致性,相关系数在0.90以上;日尺度上,净生态系统碳交换量(NEE)、总初级生产力(GPP)、生态系统呼吸(Reco)与T_s的相关系数在绝大部分测定日都小于与T_a和T_c的相关系数,但它们与T_a和T_c的相关系数差异不大;季节尺度上,冬小麦的GPP、NEE和Reco与3个温度(T_a、T_s和T_c)都呈显著的二次抛物线关系.生态系统光合作用的最适温度T_c略低于T_a的,差异约1℃左右.Reco与T_a的关系均好于与T_s的关系,与T_c、T_a关系的决定系数差异不大(0.95~0.96).研究结果可以为基于遥感方式观测的冠层辐射温度在估算碳通量中的应用提供依据.
The carbon flux of winter wheat in the Taiyuan basin was measured by box method for two years. The daily and seasonal variations of temperature (T_a), soil temperature (T_s) and canopy temperature (T_c) were compared with those of winter wheat The results showed that there was a good agreement between T_c and T_a on seasonal and seasonal scales, and the correlation coefficient was above 0.90. On the daily scale, NEE and total primary productivity (GPP) and ecosystem respiration (Reco) and T_s were less than the correlation coefficients of T_a and T_c for most of the test days, but their correlation coefficients with T_a and T_c were not significantly different. On the seasonal scale, the correlation coefficients between winter wheat GPP, NEE and Reco showed a significant quadratic parabola relationship with the three temperatures (T_a, T_s and T_c) .The optimum temperature T_c of photosynthesis in ecosystem was slightly lower than that of T_a, with a difference of about 1 ℃ .Reco and T_a The relationship between T_c and T_s is not significant (0.95 ~ 0.96) .The results of this study can provide basis for estimating the application of canopy radiation temperature based on remote sensing observations.