杉木不同生长类型对养分供应的持续效应

应用“正态分布标准差分类法”把杉木(Cunninghamia lanceolata)试验林分树高生长划分为5个生长类型,按不同生长类型进行施肥试验。结果表明,不同生长类型杉木施肥后2年生长期的树高年生长量表现为,生长类型好的群体对施肥有更好的持续促进高生长效应;生长类型差的群体,在施肥量相对少时高生长持续效应不明显,当施肥量较大时能有较好的树高年生长量持续生长效应。不同生长类型杉木胸径年生长量对施肥量的响应表现为,相同条件下,好的生长类型比差的生长类型有更好的胸径年生长量效果,施肥量相对不足时,差的生长类型群体胸径年生长持续效应逐渐衰退,好的生长类型对施肥有更好的持续促进生长效果,施肥量大对胸径年生长有更好的持续促进作用,与树高生长表现基本一致。研究表明,遗传品质好的杉木群体对立地适应能力越强,有更好的耐瘠薄能力和更好的年生长量。施肥措施对不同遗传品质生长类型杉木树高与胸径年生长量都有较好的促进效应,能有效恢复与提高杉木低产林分生长,为杉木低产与小老林林分改良提供理论指导。

Sustained Effect of Nutrient Supply for Different Genotypes of Cunninghamia lanceolata

The tree height growth of Cunninghamia lanceolata was classified into 5 types with “the standard deviation classification method of Gaussian distribution” and the fertilization test was designed according to the different growth types of C. lanceolata. It was illustrated that better growth-group was of better effect for the height growth and the inferior growth-group was not obvious for sustainable effect of the height growth under the limited fertilization and better height growth was of better growth effect under more fertilization after fertilization treatment over 2-years. The sustained effect of annual BD-growth was better compare the good growth-group with the inferior growth group, but the sustained growth effect of inferior growth group was gradually declining under the limited fertilization and the sustained growth effect of BD-growth of the good growth-group was better for fertilization treatment and the sustained growth effect of annual BD-growth was better for more fertilization treatment and the annual BD-growth was the same as the annual height-growth. It illustrated that the good growth-group was of stronger adaptation for soil and was better able to bear barren soil and it would better promote annual growth of height and BD of the different genotypes and recover and improve growth of the low-yield stands of C. lanceolata through fertilization.