Effects Of Fertilization On Growth And Wood Prperties Of Poplar Plantations

Based on the 5-year-old plantation of clone I-69, the plantation growth, nutrition, photosynthetic characteristics and wood properties were investigated. The main conclusions of the study were as follows:1) Among the different fertilizer treatments,the mean increment of diameter at breast height, tree height and volume was the largest in the urea treatment. So did the special poplar fertilizer. The results were displaying that urea 2 could be the most effective fertilizer to promote growth of poplar plantation at this specific site.2) There were significant differences in net photosynthesis rate. The results showed that the special poplar fertilizer and Ammonium phosphate fertilizer were the best ones to enhance the photosynthesis of poplar during the same period.3) Among different fertilizer treatments, the seasonal dynamics of N, P, K content in poplar leaves and branches were similar in some degree, while only the Ca, Mg contents in poplar leaves showed the similar seasonal dynamics.4) Fertilization significantly affected basic density and air dry moisture content of poplar wood, and both wood basic density and wood moisture content in the fertilization treatments were higher than these in CK (control).5) Fertilization also affected the fiber morphology of poplar woods. The longest fiber length of poplar wood was observed in the treatments of special poplar fertilizer, while widest fiber width was measured in the Urea treatments. The highest ratios of fiber length to width were founded in the special poplar fertilizer treatment,and the largest thickness of fiber wall in poplar wood was observed in Ammonium phosphate fertilizer treatment.6) Fertilization treatments had an effect on the chemical properties of poplar wood. The contents of ash and acid insoluble lignin were highest in Compound fertilizer treatment with level 3 (800 g/tree), while the crude fiber content in poplar wood was the highest in the special poplar fertilizer treatment with level 2 (400 g/tree). However, the content of alcohol-benzene extract in poplar wood was the highest in the Urea treatments.As mentioned above, the special poplar fertilizer had an obvious effect on the increment of diameter at breast height, net photosynthesis rate, basic density and fiber length of poplar wood. That meat the special poplar fertilizer was the best choice to improve the growth of poplar.