Effects of Biochar and Nitrogen Fertilizer Application Ratio on Leaf Physiology and Soil Characteristics of Bambusa tuldoides 'Swolleninternode'

As one of the main bamboo species in coastal sandy land protection forests, Bambusa tuldoides 'Swolleninternode' can effectively improve the structure of forest tree species, increase the diversity of tree species and enhance the protection efficiency. However, research on the cultivation and utilization of B. tuldoides is still relatively scarce. Therefore, in this study, B. tuldoides was used as the research object. By applying biochar and nitrogen fertilizer, the effects of different biochar and nitrogen fertilizer ratios on the physiology and soil characteristics of bamboo were analyzed, and the optimal ratio scheme was identified. The results showed that the ratio of the T5 (A2B2C3) treatment had the best effect on the total chlorophyll, non-structural carbohydrate and nutrient contents of B. tuldoides leaves, and the contents under treatments was generally higher than under the control, CK. The activities of soil invertase, nitrate reductase and nitrite reductase were significantly increased under biochar treatment, and the effects of the T5 treatment were the best. The results of principal component analysis showed that the absolute values of the coefficient of leaf potassium, phosphorus content and soil total nitrogen were larger and more important, and the comprehensive evaluation of the T5 treatment was the highest.