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应用密闭培养法，于３０℃恒温箱中对１４Ｃ标记水稻秸秆、玉米秸秆在淹水红壤及变性土中１４Ｃ与１２Ｃ间的转化与平衡进行了示踪研究。培养期为１１２天。结果表明：秸秆碳和土壤原有碳的分解以前期为快（尤其是淹水后３～７天），以后逐渐减慢，至１１２天时，秸秆碳在土壤中的分解达５４．２０％～５５．４０％，分解速率常数为６．６９×１０－３ｄ－１～７．０６×１０－３ｄ－１，半衰期为９８～１０４天。不同秸秆碳在不同土壤中的分解差异不大，显示土壤类型和秸秆种类对秸秆的分解状况影响不明显。土壤原有碳矿化特征表明变性土中１２ＣＯ２释放量始终大于红壤，虽然加秸秆处理土壤中存在着微弱的正激发和负激发（激发率小于５％），但这些处理都出现了秸秆碳的净积累。至１１２天时，土壤原有碳仅分解６．７６％～８．３３％，分解速率常数为（５．８８～７．３７）×１０－４ｄ－１，半衰期为２．５８～３．２３年。
The transformation and balance of 14C-labeled rice straw and corn stover in 14C and 12C in flooded red soil and denatured soil were traced in a 30 ℃ incubator by using the closed culture method. The cultivation period is 112 days. The results showed that the decomposition of carbon in straw and soil was rapid in the early period (especially 3 to 7 days after flooding), and then gradually slowed down. By 112 days, the decomposition of straw carbon reached 54.20% 55.40%, the decomposition rate constant is 6.69 × 10-3d-1 ~ 7.06 × 10-3d-1, the half-life is 98 ~ 104 days. Different stalks of carbon in different soil decomposition little difference, shows that soil types and straw types of straw decomposition situation is not obvious. The original carbon mineralization characteristics of soils showed that the release of 12CO2 in denudated soil was always higher than that of red soil. Although there were weak positive and negative excitation (less than 5%) in the treated soil, Net accumulation. By 112 days, the original soil carbon only decomposed 6.76% ~ 8.33%, the decomposition rate constant was (5.88 ~ 7.37) × 10-4d-1, the half-life was 2. 58 ~ 3.23 years .