修枝强度对刺槐林木生长、干形及花叶的影响

Effects of pruning intensity on growth, stem shape, flower and leaf of Robinia pseudoacacia woods

为通过修枝科学高效地培育刺槐林并实现全面利用,以刺槐实生人工林为研究对象,通过修枝抚育措施,选取6种修枝强度进行随机区组试验,以生长指标、干形指标及花叶形态与生物量为监测指标,分析比较不同修枝强度下刺槐的响应。从生长指标来看,刺槐林分平均胸径、平均材积在1/2修枝强度下生长更好且存在显著差异;修枝对平均树高、平均冠幅影响不大;随着修枝强度的增大,枝下高也随之增大。从干形指标来看,各修枝强度对尖削度无显著影响;形率上除常规修枝外,其他修枝强度均与对照相比有显著性差异;对高径比的分析表明,1/2修枝强度下干形更加细长,对照则更粗壮;随着修枝强度的增加,活冠高逐渐降低,对照与常规修枝二者存在显著差异。从单株叶数量与重量看,1/3修枝强度下收获最多。从刺槐复叶形态上看,不同修枝强度下的刺槐复叶长无显著差异,修枝强度对刺槐复叶宽与小叶长宽都有显著影响。单株花数量与重量则是对照收获最多。对于刺槐花的形态,不同修枝强度对花序长宽无显著影响,不同修枝强度下龙骨瓣、翼瓣、旗瓣与花萼在不同的花期会有不同的表现。刺槐林分对不同修枝强度的响应具有显著差异性,可通过修枝科学高效地培育刺槐林并实现全面利用。为实现能源林培育,1/2修枝强度下生长指标最好,且修下的枝同样可作为薪炭燃烧。为培育无节、饱满、通直的优质建筑材,采用1/2修枝强度对刺槐林生长、干形的促进效果最好。叶的生物量与形态指标对饲料林培育十分关键,以1/3修枝强度最佳;花的生物量与形态指标对蜜源林培育十分关键,以不修枝为宜。

In order to cultivate Robinia pseudoacacia forest scientifically and efficiently through pruning,realize comprehensive utilization of R.pseudoacacia forest,taking R.pseudoacacia plantation as the research object,through pruning measures,six pruning intensities were selected for random block test with growth index,stem shape index,flower and leaf morphology and biomass as monitoring indexes,the responses of R.pseudoacacia under different pruning intensities were analyzed and compared.In terms of growth index,the growth of average DBH and average volume of R.pseudoacacia stand grew better,and there was significant difference under 1/2 pruning intensity;pruning had little effect on the average tree height and average crown width;with the increase of pruning intensity,the height under the branch was also increased.From the stem shape index,each pruning intensity had no significant effect on the taper;there was a significant difference in the shape ratio between the control and different pruning intensities ex-cept conventional pruning;the analysis of height diameter ratio showed that the stem shape was slender under 1/2 pruning intensity,while the control was more robust;with the increase of pruning intensity,the height of living crown was decreased gradually.There were significant differences between the control and conventional pruning.In terms of the number and weight of leaves per plant,the highest yield was obtained under 1/3 pruning intensity.From the per-spective of compound leaf morphology of R.pseudoacacia,there was no significant difference in the compound leaf length of R.pseudoacacia under different pruning intensities,but pruning intensity had a significant effect on the compound leaf width and the leaflet length and width of R.pseudoacacia.The number and weight of flowers per plant were the highest in comparison of other organs.For the flower morphology of R.pseudoacacia,different pruning in-tensities had no significant effect on the inflorescence length and width.Under different pruning intensities,the keel petal,wing petal,flag petal and calyx showed different performances in different flowering periods.The response of R.pseudoacacia forest to different pruning intensities was significantly different,which could be cultivated scientifically and efficiently and fully utilized by pruning.For the cultivation of energy forests,the growth index under 1/2 pruning intensity was the best,and the pruned branches could also be burned as fuel carbon.In order to cultivate high-quality building materials that is knot free,plump and straight,1/2 pruning intensity had the best effect on the growth and stem shape of R.pseudoacacia forest.The biomass and morphological indexes of leaves are very important for the cultivation of forage forests,and 1/3 pruning intensity is the best.The biomass and morphological indexes of flowers are very important for the cultivation of nectar forests,and it is better not to prune.