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Rice production plays a crucial role in the food supply of China and a better understanding of the changes in paddy soil fertility and the management effects is of practical importance for increasing rice productivity. In this study, field sampling in a typical red soil region of subtropical China, Jiangxi Province, was used to observe changes in the soil physical, chemical, and biological properties in a cultivation chronosequence of paddy fields. After cultivation, clay (< 0.002 mm) content in the soil, which was 39% in the original uncultivated wasteland, decreased to 17% in the 80-year paddy field, while silt (0.02-0.002 mm) content increased. Additionally, macroporosity increased and pore shapes became more homogeneous. Soil pH generally increased. Soil organic C and total N contents of the 0-10 cm layer increased from 4.58 and 0.39 g kg-1 to 19.6 and 1.62 g kg-1, respectively, in the paddy fields after 30-year cultivation and then remained stable. Soil total P content increased from 0.5 to 1.3 g kg
Rice production plays a crucial role in the food supply of China and a better understanding of the changes in paddy soil fertility and the management effects is of practical importance for increasing rice productivity. In this study, field sampling in a typical red soil region of subtropical China, Jiangxi Province, was used to observe changes in the soil physical, chemical, and biological properties in a cultivation chronosequence of paddy fields. After cultivation, clay (<0.002 mm) content in the soil, which was 39% in the original uncultivated Soil organic C and total N contents of the wasteland, decreased to 17% in the 80-year paddy field, while silt (0.02-0.002 mm) content increased. 0-10 cm layer increased from 4.58 and 0.39 g kg-1 to 19.6 and 1.62 g kg-1, respectively, in the paddy fields after 30-year cultivation and then remained stable. Soil total P content increased f rom 0.5 to 1.3 g kg