漏斗状覆膜对不同密度新疆杨生长及光合特性的影响

以晋北半干旱风沙区为研究区域，采用漏斗状覆膜技术造林，探讨覆膜对不同密度（株行距分别为2 m×2 m、3 m×3 m、4 m×4 m、4 m×6 m）新疆杨生长和光合特性的影响。结果表明，漏斗状覆膜技术对不同密度新疆杨生长和光合特性有显著影响（P<0.05），2 m×2 m密度的新疆杨生长性状和光合特性表现最优，不同密度的树高、胸径、当年生长量、成活率、叶绿素含量、净光合速率表现出随密度减小而递减的规律，相关分析显示树高、胸径与净光合速率的相关系数分别为0.991、0.863，与叶绿素含量的相关系数分别为0.858、0.584。综合分析结果，在晋北半干旱风沙区，覆膜面积所占比例显著影响树木的成活与生长，新疆杨初植密度为2 m×2 m且漏斗状覆膜效果最佳。

Effects of Funnel-shaped Film Mulching on the Growth and Photosynthetic Characteristics of Populus bolleana with Different Densities

Taking the semi-arid sandy region of northern Shanxi Province as research area,the effects of funnel-shaped film mulching on the growth and photosynthesis of Populus bolleana seedlings with different planting densities (2×2,3×3,4×4,and 4 m×6 m) were examined.Significant influences (P<0.05) were observed.The growth indexes and photosynthetic characteristics were the best in the density of 2 m×2 m.The tree height (H),diameters at breast height (DBH),annual growth,survival rate,chlorophyll content (ChlC) and net photosynthetic rate (P_n) decreased with the decrease of planting density.Correlation analysis showed that the correlation coefficients were 0.991 (between H and P_n) ,0.863 (DBH and P_n),0.858 (H and ChlC) ,0.584 (DBH and ChlC),respectively.Over all,the proportion of film mulching significantly affected the survival and growth of P.bolleana,and the initial density of 2 m×2 m with funnel-shaped film mulching was suggested in semi-arid sandy area of Northern Shanxi Province.