Temporal and Spatial Variation Characteristics of Soil Nutrient Content and Microorganism Quantities of Rice Paddy in Core Zone of Yuanyang Terrace

PurposeTo investigate the temporal and spatial variation characteristics of nutrient contents and microorganism quantities of rice paddy in core zone of Yuanyang Terrace.

MethodSoils were sampled from rice paddy of Qingkou Village in Yuanyang Terrace at different altitudes (1 450, 1 500, 1 600, 1 700 and 1 800 m) in different months. The nutrient contents (total nitrogen, phosphorus, potassium, and available nitrogen, phosphorus and potassium) and the microorganism quantities (bacteria, actinomycetes, azotobacter, cellulose decomposing bacteria and fungi) in soils were analyzed.

ResultsThe contents of total nitrogen and potassium in soils at a low altitude were higher than that at a high altitude. The contents of available nitrogen and phosphorus at the high altitudes (1 700 and 1 800 m) were greater than those at relatively low altitudes (1 450 and 1 500 m). The contents of available nitrogen and phosphorus in soils at the fallow period were higher than that at the rice growth period. On the whole, the microorganisms’ quantities were higher in the rice paddy at a low altitude (1 450, 1 500 m). The quantities of azotobacter and actinomycetes in March, bacteria and fungi in May, and cellulose decomposing bacteria in September were relatively high.

ConclusionThe contents of available nutrients and the microorganism quantities in rice paddy in the core zone of Yuanyang Terrace were significantly influenced by season, and showed obvious vertical distribution characteristics.