施用磷肥对马尾松种源生长和木材基本密度的影响

利用设置在福建武平的12年生马尾松Pinus massoniana种源与磷肥互作试验林,研究磷肥对5个优良种源生长、形质和木材基本密度的影响及其间的互作效应.结果表明:马尾松不同种源对磷肥的反应差异较大,且因性状而异.福建武平马尾松种源属于生长对磷肥不敏感的耐低磷型优良种源；广东高州种源的磷肥生长效果好、持续期长,属磷肥敏感型优良种源；广东信宜、广西岑溪和江西崇义种源对磷肥的生长反应因性状和林龄而有较大的波动,12年生时胸径或树高生长的磷肥效应显著(P＜0.05).相对于生长性状,马尾松种源树干通直度和木材基本密度受磷肥的影响较小.研究发现:未施磷肥的低磷条件下,福建武平种源较其他种源表现出明显的生长优势,其胸径、树高生长量最大,江西崇义种源的生长表现相对较差；当施用磷肥后,两广种源及江西崇义种源与福建武平种源的生长差异缩小,广西岑溪和广东高州种源生长量则超过了福建武平种源.木材基本密度和树干通直度在3种磷肥处理下的种源间差异较小,仅见在低磷条件下江西崇义种源的木材基本密度显著低于其他4个种源(P＜0.05).统计分析还表明,马尾松树高和木材基本密度存在一定的种源与磷肥互作,并依据各处理因素的主效应及其间的交互效应,为纸浆材和锯材选出最佳组合.图1表4参21

Influence of phosphorus on growth and wood basic density of Pinus massoniana provenances

In order to select optimal combination of provenance and phosphorus level for pulp wood and saw timber,a 12-year-old Pinus massoniana（masson pine） trial was used to reveal the main effect and interaction of three phosphorus levels（0,100 and 400 g·tree-1） and five provenances（Wuping of Fujian,Gaozhou of Guangdong,Xinyi of Guangdong,Cenxi of Guangxi,and Chongyi of Jiangxi） on growth,stem-form qualities,and wood basic density（WBD）.A randomized complete design with four blocks of twenty-eight trees per plot was used and selected 6 to 8 trees inside every plot.Variance analysis was done using GLM program in SAS sofeware.Results indicated that growth and WBD were not significant difference（P0.01） for Wuping between three phosphorus levels,suggesting Wuping an excellent provenance with tolerance to low phosphorus.Gaozhou was significant increasing for growth with phosphorus level higher,and had a long duration to phosphorus.In the condition of phosphorus not supplied,Wuping had the significant largest（P0.05） diameter at breast height（DBH） and height and was superior to the other provenances,whereas Chongyi was the worst,lower 19.8% and 12.7% for DBH and height than Wuping.Provenances from Gaozhou,Xinyi,Cenxi,and Chongyi had the best fertilizer efficiency;however,with Wuping differences decreased when phosphorus level were 100 and 400 g·tree-1.For WBD Chongyi was considerabley lower（P0.05） than the other provenances under 0 g·tree-1 phosphorus level.The experiment also showed that provenance by phosphorus interaction was significant for height（P0.01） and WBD（P0.05）.Based on the main effects and interactions,optimal combinations of Wuping under 0 g·tree-1 phosphorus level,and Gaozhou under 100 g·tree-1 phosphorus level were selected for pulpwood and sawtimber,repectively.