| In Hebei Weixian County, this study selected nursery field Populus base ratio of fertilization field experiment, using L9(34) orthogonal experimental design also studied N, P, K ratio of fertilization on clones S86, BT17 DBH, tree high volume growth, physiological characteristics, chlorophyll and nutrient content, growth and dynamic change of the Populus and Populus roots, diameter and leaf nutrient content changes in the law, and to study the different varieties of Populus make the most reasonable good fertilization period, fertilizer type and amount of fertilization, the establishment of fast growing timber Populus rational fertilization technology solutions for the fast growing Populus to create the forest to provide a theoretical basis for further rapid development of poplar industry. The results are as follows:(1) N fertilizer affect the growth of Populus major fertilizer timber, followed by P fertilizer, K fertilizer, and the best fertilizer rate for individual volume growth of Populus is:variety S86 is N3P3K1 (Urea 650 g/strain, Calcium super-phosphate 1000 g/strain, Potassium chloride 0 g/strain), variety BT17 is N3P2K1 (Urea 650 g/strain, Calcium super-phosphate 500 g/strain, potassium chloride 0 g/ strain).(2) Fertilizer should be selected during the Chinese white poplar tree height, before the fast peak, that early in May. If a second dressing again, it should choose the tree diameter and height growth before the peak of fertilizer, top dressing time again during the period should be selected in July.(3) N, P, K fertilizers on Populus net photosynthesis, transpiration, stomatal conductance had no significant effect (P<0.05), affected by very poor value of the net tomentosa photosynthesis, transpiration, stomatal conductance the size of the order of fertilization factor:N Fertilizer>P Fertilizer> K fertilizer. And chlorophyll content in Populus is the biggest deal P9 (Urea 650 g/strain, Calcium super-phosphate 1000 g/strain, potassium chloride 150 g/strain).(4) Leaf nitrogen fertilization, phosphorus and potassium content in promoting nitrogen, phosphorus and potassium absorption. Leaf N and P content of the basic monthly change showed a single peak curve, K content in the basic rate of monthly change little; and Populus tissues N, P element content is the order:leaf> stem> root; K element content Populus tissues is the accumulation of the order:leaf> root> stem. |
