The Nutrient Balance And Cycling Of Farming Systems: A Case Study Of Quzhou County

Based on the analysis of data from hoursehold survey, literature and statistics in Quzhou county of Hebei province, the nutrient balance was analysed and evaluated under different scale and different crop systems. The main results were summaried as follows:1. In Quzhou county, the balance of N, P was highly positve and annually increased. The balance of organic matter had positive but decreased anually while the balance of K was negative and decreased continuely.2. There were significantly different of nutrient balance among different land use type of hourshold. In 1998 and 1999, the nitrogen surplus of vegetable field were 126.59% and 154.29%, while wheat/maize field balanced, the other land use had a little surplus. The reason is that there was great difference of fertilizer input among the different kind of land use types. In vegetable and winter wheat fields, the input of N,P and K were high while were relatively low in the soybeen and maize field. In the wheat/maize rotation fields of the two years, the input of N,P and K for the winter wheat account for 67.27% and 67.41 % , 86.43%and 84.72%, 54.43%and 75.88%of total inputs respectively so that much less fertilizer were used for maize.3. Because of the differences of natural, economical environment and self economy power, there were great differences of fertilizer input among different types of farmers. The input of fertilizer from off farm hoursehold was more reasonable than mainly farming hourshold and mainly off farming household, while farming hourshold was the most unreasonable.4.Through the calculation and analysis of the nutrient flow of agro-pastoral ecosystem in Gongcun, the results show as follows: the export amount of commodities is higher. The surplus of N and P was less than that of Quzhou county, while the surplus of organic input was more than that of Quzhou county. The nutrient balance in different kind of crops and cropping systems, as well as the nutrient input of different farmers were similar pattern with Quzhou county.