Abstract:

The nutrient changes of 260 paddy soils sampled from Zhejiang province in 2009 were studied based on the soil nutrient data obtained from the Second National Soil Survey. The results showed that the value of soil pH decreased obviously after 25 years of continuous cropping. The ratio of paddy field at pH value of 551 to 650 decreased from 593% in 1984 to 223% in 2009. Moreover， the mean value of soil organic matter was decreased by 139%. However， the level of soil total nitrogen was higher. The content of availableP markedly increased， especially the ratio of paddy field with availableP content > 200 mg· kg-1 increased from 53% in 1984 to 250% in 2009. The mean value of availableK was decreased by 348%. The Kdeficiency of paddy fields is still very common in Zhejiang province．

Key words: paddy soil, soil nutrient, dynamic change, Zhejiang Province