关键词: 耐盐性, 耐盐性

Abstract: Studies on nutrients (nitrogen, phosphorus and potassium) input, output and balance are critical for high efficiency and sustainable use of these nutrients on farmlands. The macro-scale and micro-scale analysis methods were used to analyze the input, output and balance of N, P2O5 and K2O in Hebei Province in 2010. The sources and losses of the nutrients were generally from chemical fertilizer, manure and urine, dry- wet precipitation, irrigation, microbial N-fixing, seeds, etc. The results indicated that the total inputs of N, P2O5 and K2O were 2800 kt, 1160 kt and 960 kt, while the inputs of N, P2O5 and K2O from chemical fertilizers were 1860, 968 and 400 kt, which accounted the total nutrient inputs for 66.4%, 83.4% and 41.7%, respectively. The inputs of N, P2O5 and K2O from manure and urine were 210 kt, 98 kt and 144 kt, which accounted the total nutrient inputs for 7.5%, 8.4% and 15.0%, respectively. The outputs of N, P2O5 and K2O were respectively 2400, 660 and 990 kt, while surplus rates of N and P2O5 were 16.8% and 77.1% but deficit rate of K2O was -3.2%. It concluded that the management measures of stabilizing nitrogen input, decreasing phosphorus input and increasing potassium input should be taken into account for the supply of farmland nutrients and improvement of soil fertility.