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14C标记的羊粪、杂交狼尾草（象草）及其根部分别施于淋溶土中，在30℃培养365天。土壤保持旱地（70％WHC）和淹水两种状态，进行有机碳在土壤中分解的对比试验。另一组试验采用14C标记的水稻秸和玉米秸，分别施于老成土和变性土中，在上述相同的水分条件下于30℃培养112天进行对比。所有加入的不同有机物料。不论是在何种土壤，其在淹水土壤中的有机碳分解速率均快于旱地土壤，而前者的残留率却明显低于后者。淹水处理中各种不同有机物料的分解半衰期约为旱地相应处理的1．4—2．0倍。这和有关有机质在旱地和水田土壤中分解速率的传统概念相反。作者认为如果旱地和水田的土壤条件均适宜于微生物的代谢作用，水田土壤中不论是有机碳的分解速率还是分解量实质上均大于旱地土壤。
14C labeled sheep manure, hybrid Pennisetum (grass) and its roots were applied to the leaching soil, cultured at 30 ℃ for 365 days. Soil conservation in drylands (70% WHC) and flooded two states, organic carbon in the soil decomposition comparative test. Another group of experiments using 14C labeled rice straw and corn stalks were applied to the old soil and denaturalized soil, respectively, in the above water conditions at 30 ℃ for 112 days for comparison. All the different organic materials added. The soil organic carbon decomposition rates in flooded soils were faster than those in upland soils, however, the former was significantly lower than the latter in residual soils. The half-life of decomposition of various organic materials in flooding treatment is about 1.4-2.0 times of the corresponding treatment in dry land. This is the opposite of the traditional concept of the rate of decomposition of organic matter in dry and paddy soils. The authors believe that if the soil conditions in both dry and paddy fields are suitable for microbial metabolism, both the rate of decomposition and the amount of decomposition of organic carbon in paddy soils are substantially greater than in dryland soils.