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通过实验室及野外观测实验发现：气温变化是导致稻田ＣＨ４排放日变化的本质原因，实验室实验中发现土壤温度变化能够引起ＣＨ４排放率的明显变化，但是后者比前者滞后１０～１１小时；在调整相位差后，ＣＨ４排放率与土壤温度有很好的线性相关（Ｒ＞０．８０，Ｎ＝２４），ｄＦ／ｄＴｓｏｉｌ的平均值为６１．０±５９．０μｇＣＨ４·ｍ－２·ｈ－１·Ｋ－１。实际稻田中一日之间的ＣＨ４排放率与灌溉水温度、土壤浅层（＜２ｃｍ）温度以及空气温度相关性最大，ｄＦ／ｄｔｗａｔｅｒ为２００．０～４４５０．０μｇＣＨ４·ｍ－２·ｈ－１·Ｋ－１，但是与土壤深层（＞５ｃｍ）温度的相关性较差；一日之间气温的变化引起ＣＨ４三个传输路径的变化是导致ＣＨ４排放日变化的原因。稻田ＣＨ４排放日变化的温度效应的大小对于早稻相对稳定，而对晚稻则随时间呈明显的下降趋势，结合土壤ＣＮ４排放率的季节变化，这种现象是由于整个水稻生长季节中，气温以及水稻生长状态所导致的ＣＨ４传输效率的变化引起的。大气、稻田灌溉水、土壤类型以及水稻品种等都会影响ＣＨ４排放日变化的温度效应。由于早晚稻温度变化趋势的不同使早稻与晚稻ＣＨ４排放的季节变化形式有极大的差别；日平均温度与甲烷排放日平均值?
Laboratory and field observations showed that the change of air temperature was the essential reason for the diurnal variation of CH4 emission in paddy field. In laboratory experiments, it was found that the change of soil temperature caused obvious change of CH4 emission rate, but the latter lagged 10-1 11 hours. After adjusting the phase difference, the CH4 emission rate has a good linear correlation with soil temperature (R> 0.80, N = 24), and the average value of dF / dTsoil is 61.0 ± 59.0μgCH4 · m-2 · h -1 · K-1. The daily CH4 emission rate in the actual paddy field had the highest correlation with irrigation water temperature, shallow soil (<2cm) temperature and air temperature, and dF / dtwater was 200.0 ~ 4450.0μg CH4 · m-2 · h-1 · K-1, but the correlation with the depth of soil (> 5cm) is poor. The changes in the three CH4 transport paths caused by the change of air temperature in one day are the causes of the diurnal variations of CH4 emission. The temperature effect of diurnal changes of CH4 emission in paddy field was relatively stable for early rice and late rice showed a declining trend with time. Combined with the seasonal change of soil CN4 emission rate, this phenomenon was mainly caused by the increase of temperature and rice temperature Growth conditions caused by changes in the efficiency of CH4 transmission caused. Atmosphere, irrigation water in paddy fields, soil types and rice varieties all affect the temperature effect of diurnal variations in CH4 emissions. Due to the difference of temperature change between morning and evening rice, the seasonal variations of CH4 emission of early rice and late rice are greatly different. The average daily temperature and methane emission average day?