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[目的]研究连作对不同品种杨树人工林叶片养分及生长量的影响。[方法]通过野外调查、室内试验对苏北杨树产区不同种植代次和不同品种的杨树人工林树高、胸径、材积和其叶片TN、TP、TK3种营养元素含量进行测定。[结果]2个品种不同林龄林分随着代次增加叶片TN、TP、TK含量变化不同,但是随着林龄的增大,叶片TN、TP、TK含量呈下降趋势;随代数增加,Ⅰ-69杨与Ⅰ-72杨树高变化的趋势相似,7与10年生林的树高受代次增加的影响较为稳定,呈逐代下降趋势,而4年生林的树高随代次增加,表现为先增后减;胸径随代次变化规律与树高随代次变化规律基本一致;随栽植代次的增加,7和10年生林材积生长量下降且存在显著差异。[结论]该研究结果为实现人工林合理施肥与管理、提高杨树人工林生产力、实现人工林可持续经营提供依据。
[Objective] The research aimed to study the effects of continuous cropping on leaf nutrient and growth of poplar plantations. [Method] The tree height, diameter at breast height, volume, and TN, TP, TK content of three kinds of poplar plantations at different planting generations and different cultivars in northern Jiangsu were studied by field investigation and indoor experiment. [Result] The contents of TN, TP and TK in leaves of two cultivars with different ages varied with different times. However, the content of TN, TP and TK showed a decreasing trend with increasing age. With the increase of generations, The trend of I-69 poplar and Ⅰ-72 poplar was highly similar. The tree height of 7-year-old and 10-year-old forest was more stable than that of I-69 poplar, which showed a downward trend from generation to generation. For the first increase and then decrease; the DBH variation with the generation and the tree height with the generation change rule is basically the same; with the increase of planting generations, 7 and 10 annual growth of forest volume decreased and there are significant differences. [Conclusion] The results of this study provided the basis for achieving rational fertilization and management of plantations, increasing the productivity of poplar plantation and realizing the sustainable management of plantations.