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水稻土甲烷的产生受环境因子的影响。为了比较不同温度下不同p H值水稻土甲烷产生的差异,同时分析不同温度下产甲烷随时间的变化与理化因子变化的相关性,以酸性砂质水稻土(p H值4.67)和偏碱性粘质水稻土(p H值7.88)为研究对象,在15℃、25℃、37℃以及50℃4个温度下进行为期100 d的厌氧培养,定期测定培养过程中产甲烷累积量以及土壤理化因子p H值、氨氮以及有机碳的变化。结果表明,在15℃~37℃范围内初始有机碳含量以及氨氮浓度高的酸性砂质水稻土产甲烷大于偏碱性粘质水稻土;2种土壤产甲烷量以及产甲烷速率均随温度升高而增大,均在37℃时达到最大值;然而在50℃高温下,酸性砂质水稻土甲烷产量明显小于碱性粘质水稻土,且其产甲烷量以及产甲烷速率明显下降,甚至低于25℃,而碱性粘质土壤产甲烷量依然高于37℃,产甲烷速率与37℃相比没有明显下降,说明高温对酸性砂质水稻土的影响大于碱性粘质水稻土。在厌氧培养过程中,不同温度下氨氮浓度与产甲烷始终保持比较高的相关性,而有机碳含量的变化与产甲烷的相关性随温度升高而下降,说明高温下影响土壤产甲烷的因素较低温复杂得多。与碱性土壤相比,不同温度下酸性土壤p H值的变化对产甲烷的影响较大。
The production of paddy soil methane is affected by environmental factors. In order to compare the differences of methane production in paddy soils with different p H values at different temperatures, the correlation between methane production and physicochemical factors at different temperatures was analyzed. (PH 7.88) was used as the research object to conduct anaerobic culture for 100 days at 15 ℃, 25 ℃, 37 ℃ and 50 ℃ for 100 days. The methane accumulation in soil and soil Physical and chemical factors p H value, ammonia nitrogen and organic carbon changes. The results showed that the initial production of organic carbon and the concentration of ammonia nitrogen in the range of 15 ℃ ~ 37 ℃ were higher than that of the alkaline soil in acidic sandy paddy soil. Both the yield of methane and the rate of methane production increased with the increase of temperature But reached the maximum at 37 ℃. However, under the high temperature of 50 ℃, the yield of methane in acidic sandy paddy soil was significantly less than that in alkaline clay soil, and the methane production and methane production rate decreased obviously, even lower At 25 ℃, the yield of methane in alkaline clayey soil was still higher than 37 ℃, and the rate of methane production did not decrease obviously compared with that at 37 ℃, which indicated that the effect of high temperature on acid sandy soil was more than that of alkaline clay soil. During the process of anaerobic culture, the ammonia nitrogen concentration at different temperatures always maintains a relatively high correlation with methane production. However, the correlation between the changes of organic carbon content and methane production decreases with the increase of temperature, indicating that the effect of methane on methane production at high temperature Factors are much more complicated than lower temperatures. Compared with alkaline soil, the change of p H value of acid soil at different temperatures has a greater impact on methane production.