Changes in Enzyme Activities in Corn and Paddy Field Soils with Different Fertilization Management

• Main Authors: Chiang, Shwu Jen, 江淑真
• Other Authors: Lai, C. M.
• Format: Others
• Language: zh-TW
• Published: 1998
• Online Access: http://ndltd.ncl.edu.tw/handle/26626047609115177881

碩士 === 國立臺灣大學 === 農業化學系研究所 === 86 === Abstract An experimental field in Taiwan Agricultural Research Institute was selected to study the changes in soil enzyme activities with different fertilization management under corn-rice rotational cropping system. The soils were sampled from corn field and paddy field, and the activities of three enzymes related to nitrogen cycle ( urease, L-asparaginase, and amidase ), one enzyme related to carbon cycle ( cellulase ), two enzymes related to sulfur cycle ( arylsulfatase and rhodanese ), were analyzed. The effects of soil particlesize and water content on eight soil enzyme activities, and the relationships between plant nutrients and soil enzyme activities were also examined. The experimental field was designed as RCBD with four replications and seven treatments, including: (1) CK, (2) Chem-N, (3) Comp, (4) Comp+1/3N, (5) Comp+2/3N, (6) GM+1/3N, (7) Peat+1/3N. Results from the effects of different fertilization management on enzyme activities in corn field soils show that the activities of urease, amidase, and cellulase in soils were increased by Chem-N treatment. The activities of urease, L- asparaginase, cellulase, and acid phosphatase in soils were increased by Comp treatment. The activities of urease, L-asparaginase, amidase, cellulase, acid phosphatase, and phosphodiesterase in soils were increased by organic materials and Chem-N treatments. Among organic materials and Chem-N treatments, Comp+1/3N was the best one to increase the activities of the soil enzymes, but GM+1/3N and Peat+1/3N were the worse treatments. The activities of arylsulfatase and rhodanese were not increased significantly by all the treatments in this study. The changes in activities of the eight soil enzymes during the corn growing periods were not the same. The activities of urease, L-asparaginase, amidase, and cellulase were highest in seedling stage of corn. The activities of acid phosphatase, phosphodiesterase, and arylsulfatase were highest in harvesting stage of corn. The activities of rhodanese was highest in tasseling stage of corn. Results from the effects of different fertilization management on enzyme activities in paddy field soils show that the activities of acid phosphatase in soils were increased by Chem-N treatment. The activities of urease, L- asparaginase, cellulase, acid phosphatase, phosphodiesterase, and arylsulfatase in soils were increased by Comp treatment. The activities of urease, L- asparaginase, amidase, cellulase, acid phosphatase, phosphodiesterase, and arylsulfatase in soils were increased by organic materials and Chem-N treatments. Among organic materials and Chem-N treatments, Comp+1/3N and Comp+2/3N were the best treatments to increase the activities of the soil enzymes, but GM+1/3N and Peat+1/3N were the worse treatments. The activities of rhodanese were not increased significantly by all the treatments in this study. The activities of urease, L-asparaginase, amidase, cellulase, acid phosphatase, phosphodiesterase, arylsulfatase, and rhodanese were highest in active tillering stage of rice. Results from the effects of soil particle size and water content on enzyme activities in paddy field soils showed that the correlation of activities of amidase between < 5 mm fresh soils and < 2 mm air-dried soils were not significant. The correlation of activities of acid phosphatase and phosphodiesterase between < 5 mm fresh soils and < 2 mm air-dried soils were significant. ( p ＜0.01 ). The correlation of activities of the other soil enzymes between < 5 mm fresh soils and < 2 mm air-dried soils varies with the stages of rice growing periods. Thus, using < 5 mm fresh soil samples to determine soil enzyme activities could be similar to the condition of soil enzymes in natural environment. Results from the relationships of enzyme activities and inorganic nutrients in corn field soils and paddy field soils showed that the activities of acid phosphatase and phosphodiesterase have significant relationships with inorganic phosphorus content ( p ＜0.01 ).