关键词: 方差分析, 方差分析

Abstract: The “3414” partial experiment design was carried out to study the effects of different nitrogen and phosphorus ratios on the growth of Chinese ash (Fraxinus chinensis) and soil properties. The results showed that the application of N and P significantly influenced the growth of DBH (diameter at breast height) and tree height, the increment percentages of which were significantly increased in all treatments receiving N and P fertilizers, in contrast to the unfertilized control. The effect of treatment N2P2 was the best, and the second one was N2P1. Nitrogen had better effects than P to promote the growth of Chinese ash. The contents of available N and P in leaves as well as photosynthesis rate and stomatal conductance were evidently enhanced by the application of N and P, which also increase the content of available K and organic matter in soil to some extent. However, no effects were found on soil pH and salt content. Fertilizer recommended rates were simulated by the model of two-factor. The results indicated that the maximum of DBH was achieved when the rates of N and P2O5 were 0.159 and 0.0181 kg/plant, respectively. Considering the best interests, the recommended rates of N and P were 0.159 and 0.0176 kg/plant.