对海拔、立地级、坡向、林分结构和立竹度等林学因子不同的毛竹[Phyllostachys edulis (Carr.) H. de Lehaie]人工林中毛竹材的化学组成进行了比较分析。 结果表明:随海拔的升高(300、600 和 900 m),毛竹材中热水抽出物、苯-醇抽出物、Klason 木素和灰分含量提高,1% 氢氧化钠抽出物和纤维素含量减少,其中,1% 氢氧化钠抽出物、苯-醇抽出物及灰分含量差异极显著,而海拔 300 和 600 m 林地中毛竹材的热水抽出物和纤维素含量与海拔 900 m林地有极显著差异;海拔 600 m 林地中毛竹材的戊聚糖含量最低,且 3 种林地间戊聚糖含量有极显著差异。 立地级Ⅰ、Ⅱ和Ⅲ级的毛竹人工林中毛竹材的热水抽出物、1% 氢氧化钠抽出物、Klason 木素和灰分含量均依次增高,戊聚糖含量依次减少;Ⅱ级林地中毛竹材的苯-醇抽出物和纤维素含量最高;立地级对毛竹材的热水抽出物、1% 氢氧化钠抽出物和纤维素含量均有极显著影响。 阴坡的毛竹材中热水抽出物、1% 氢氧化钠抽出物、苯-醇抽出物、纤维素和灰分含量均高于阳坡,而戊聚糖和 Klason 木素含量均低于阳坡;坡向对毛竹材中热水抽出物、1% 氢氧化钠抽出物和苯-醇抽出物含量有极显著影响,对纤维素、戊聚糖、Klason 木素和灰分含量的影响不显著。 毛竹纯林中毛竹材的 1% 氢氧化钠抽出物、苯-醇抽出物和纤维素含量均高于毛竹-杉木[ Cunninghamia lanceolata ( Lamb.)Hook.]混交林和竹-阔混交林,戊聚糖、Klason 木素和灰分的含量介于后二者之间;林分结构对毛竹材中戊聚糖、Klason 木素和灰分含量的影响不显著。 随立竹度的提高(1 500、3 000 和 4 500 株· hm^-2 ),毛竹材中 1% 氢氧化钠抽出物含量提高,戊聚糖和 Klason 木素的含量减少;立竹度 3 000 株· hm^-2 的林地中毛竹材的苯-醇抽出物、纤维素和灰分含量最高,热水抽出物含量最低;立竹度对毛竹材中热水抽出物和苯-醇抽出物含量有极显著影响。 综合分析结果显示,定向培育毛竹纸浆材应选择海拔300 m 的阴坡Ⅱ级林地营造毛竹纯林,立竹度应控制在3 000株· hm^-2左右。

 

Chemical compositions of Moso[ Phyllostachys edulis ( Carr.) H. de Lehaie] culm-wood in Moso plantations with different forestry factors such as altitude, site class, aspect, stand structure and bamboo density were comparatively analyzed. The results show that with rising of altitude (300, 600 and 900 m), contents of hot water extractive, benzene-ethanol extractive, Klason lignin and ash of Moso culm-wood enhance, but contents of 1% NaOH extractive and cellulose decrease. And contents of 1% NaOH extractive, benzene-ethanol extractive and ash appear extremely significant differences among three stands with different altitudes, while contents of hot water extractive and cellulose of Moso culm-wood at altitude 300 and 600 m stands have extremely significant differences with those at altitude 900 m stand. Pentosan content of Moso culm-wood at altitude 600 m stand is the lowest, and appears extremely significant difference among three stands with different altitudes. Contents of hot water extractive, 1%NaOH extractive, Klason lignin and ash of Moso culm-wood atⅠ, Ⅱ and Ⅲ site class plantations increase while content of pentosan decreases, successively. Contents of benzene-ethanol extractive and cellulose of Moso culm-wood at Ⅱ site class plantation are the highest. The site class has a highly significant influence on contents of hot water extractive, 1% NaOH extractive and cellulose of Moso culm-wood. Contents of hot water extractive, 1% NaOH extractive, benzene-ethanol extractive, cellulose and ash of Moso culm-wood at shady slope are all higher while contents of pentosan and Klason lignin are lower than those at sunny slope. The aspect has a highly significant influence on contents of hot water extractive, 1% NaOH extractive and benzene-ethanol extractive and has no influence on contents of cellulose, pentosan, Klason lignin and ash. Contents of 1% NaOH extractive, benzene-ethanol extractive and cellulose of Moso culm-wood in P. edulis pure forest are higher than those in mixed forests of P. edulis-Cunninghamia lanceolata ( Lamb.) Hook. and P. edulis-broadleaves species, while contents of pentosan, Klason lignin and ash in P. edulis pure forest lie between those in the later two mixed forests. And stand structure has no significant effect on contents of pentosan, Klason lignin and ash. With rising of bamboo density (1 500,3 000 and 4 500 plants· hm^-2), content of 1% NaOH extractive increases, while contents of pentosan and Klason lignin decrease. In which, contents of benzene-ethanol extractive, cellulose and ash of Moso culm-wood in the plantation with a bamboo density of 3 000 plants· hm^-2 are the highest while hot water extractive content is the lowest. And the bamboo density has an extremely significant influence on contents of hot water extractive and benzene-ethanol extractive. The result of comprehensively analysis indicates that in order to orientally cultivate the Moso culm-wood suitable for pulp-paper material, it should be chosen the forest land of altitude 300 m at shady slope of Ⅱ site class to create pure forest of P. edulis with a bamboo density of about 3 000 plants· hm^-2.