不同有机栽培基质对粗梗木莲幼苗生长的影响

分别用树皮、生物有机肥、菌棒3种有机基质作为粗梗木莲容器育苗的肥源，与细黄心土按有机基质30％，细黄心土70％的比例混合配比。用10cm×10cm黑色软塑料钵栽植。随机区组设计，50株为1小区，3次重复。结果表明，生物有机肥能显著提高苗木的株高、地径、叶片数和叶面积等形态指标，也能显著提高苗木的总鲜重、叶鲜重、茎鲜重、根鲜重、总干重和茎干重等生物量指标，是一种较为适合粗梗木莲容器育苗的有机基质。树皮有机基质与菌棒基质的效果相对较差，但也可作为粗梗木莲容器育苗的一种基质使用。     

Bark consumption by voles in relation to geographical origin of tree species

Voles have caused more damage by bark consumption to Picea abies and Pinus contorta seedlings from southern than those from northern origins when planted in northern Scandinavia. In field and laboratory experiments, indigenous Scandinavian tree species from different origins and of various phenological stages were tested for susceptability to vole attacks. Seedlings from northern sites and late phenological stages were most severely attacked by both bank voles Clethrionomys glareolus and field voles Microtus agrestis, while a few aspen clones differed independently of origin. Bark consumption by the two vole species was strongly and negatively related to the concentration of crude fibre in the examined twigs. Bank voles also reacted positively to the content of nitrogen‐free extracts. Differences in preferences for seedlings from different geographical regions appear to result from differences in the bark at the end of growth and in the frost‐hardening process in autumn. Plants transferred northwards probably will not harden in a climatically appropriate way, will contain low concentration of fibre in winter, and will be a preferred food for voles.     

New method to determine the hydroxyl value in liquefied bark as Polyurethane material

Conclusions When the hydroxyl values of materials containing phenolic 3 or sterically hindered hydroxyl groups were determined by the esterification method, the values were considerably smaller than the theoretical values. In contrast, the NCO method provided hydroxyl values much closer to the theoretical values for such materials, though the values varied depending on the kinds and amounts of catalysts.The quantity of hydroxyl groups reacting with the NCO group could be directly determined by the NCO method using a catalyst mixture consisting of DABCO and DBTDL in a molar ratio of 21. Therefore, this method can be considered useful for determining the hydroxyl value before preparing polyurethane from liquefied wood or bark.Part of this paper was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 1988     

树皮的化学改性及其吸附特性研究

通过甲醛和环氧氯丙烷交联马尾松树皮，得到两种改性树皮；甲醛改性树皮（简称FMB）和环氧氯丙烷改性树皮（简称EMB）。讨论了不同改性条件对树皮得率的影响，研究了FMB、EMB对阳离子型染料碱性桃红和重金属离子铜离子的吸附特性，实验结果表明：（1）通过上述改性，可改善树皮的化学稳定性，避免有色物质的流出；（2）与未改性树皮相比，FMB、EMB对碱性桃红的吸附容量提高了约50%，达95mg/g；对铜离子的吸附容量提高了约56%，达78mg/g；（3）两种改性方法相比，吸附容量相近，但甲醛法改性成本低廉，污染少，综上所述，FMB、EMB是一种具有潜在应用价值的水处理材料。     

紫胶蚧7种寄主植物“树皮”比较解剖与寄生特性研究

不同寄主植物“树皮”从外向内皆由周皮、皮层、次生韧皮部构成,但是在每层结构中,不同寄主之间存在一定的差异。大叶千斤拔的周皮最薄,光叶合欢的皮层最薄。在栾树和苏门答腊金合欢的周皮中,局部地方木栓层显著加厚,滇刺枣的木栓层角质化呈点状分布。滇刺枣石细胞纤维层最厚,共有4层,聚果榕、苏门答腊金合欢的皮层中未见连续的石细胞纤维层。苏门答腊金合欢的韧皮部最薄,聚果榕的韧皮部最厚,栾树周皮到次生韧皮部的最小距离最短,苏门答腊金合欢到韧皮部的最大距离最短。苏门答腊金合欢筛管在单位面积的分布密度最大。在筛分子具功能区,大叶千斤拔、栾树、滇刺枣射线为单列,偶有多列;聚果榕、光叶合欢、久树射线单列、双列、多列并存;苏门答腊金合欢射线为多列。文中还从寄主植物的韧皮部厚度、节管密度等解剖特征研究了不同寄主树对紫胶蚧的固虫密度和死亡的影响。     

巨尾桉树皮率估测模型的研究

利用巨尾桉(EUCALYP GRANDIS×UROPHYLLA)实测数据,采用数学模型模拟的手段,研究、分析树皮体积率和树皮干重率的估计方法。结果表明,用胸径估计树皮体积率和树皮干重率的效果与用树干带皮材积估计树皮体积率和树皮干重率的效果相近,树皮体积率的估计精度优于树皮干重率的估计精度。     

高效液相色谱法测定白桦树皮中白桦酯醇的含量

为了提取白桦三萜炎物质，建立了高效液相色谱法测定白桦(Betula platyphylla Suk．)树皮中白桦酯醇含量的方法、色谱柱为ODS C18；流动相为甲醇：水(88：12)，紫外检测波长为210nm，柱温30℃；柱压6．4MPa，流速1mL／min，白桦酯醇的线性范围为15．0～300．0μg，平均回收率为93.93％。对同一样品重复测定5次，相对标准偏差为0．36％，与比色法和气相色谱法相比，本法更准确、简便。     

橡胶树树皮坏死:症状学、病原学、流行病学方面的发展和树干生理病症的发因

橡胶树排胶障碍是制约全球橡胶种植园发展的主要因素,它是由以下两个不同病症导致的:(1)割面干涸(TPD)-过度割胶引起的可逆生理反应,(2)割面树皮坏死(BN)-由橡胶树根颈韧皮部扩展的不可逆病变。树皮坏死(BN)目前危害了世界大部分胶园,胶园受害严重度取决于橡胶品种、树龄、种植地和种植地区。橡胶树树皮病的多态性一直是一个有争议的问题,通过对许多胶园的调研,该问题最近得到了解决。虽然前期和最近的病原分析不具决定性,但是环境因素却显示出同树皮坏死有联系。在对近期开割的胶园进行流行病调查,发现早期患病胶树地点呈非随机性。这些易发病区主要靠近沼泽地、路旁、风干行、原推土机过道、树林树桩残余地和斜坡缓冲地段的附近区域。在树皮坏死发生区,虽然没有发现与土壤化学因素有明显的关系,但是,土壤物理分析(如透度法)却表明,土壤的较高紧实度常同患病胶树的根系生长较弱有关联。另外,通常在芽接点接合处可以很好地观察到树皮坏死早期症状。通过PMS压力室获得的大量可比生态生理的测量数据显示,患病胶树呈现水分协迫特征,意味着病树树干同其根系存在着一种非理想的维管关系。因此,同土壤紧实度相关的土壤缺水状况、旱季不能满足胶树水分需求的脆弱根系、被扰乱的树液流动和土壤排水等因素的共同作用,被怀疑是诱导树干接芽区树皮坏死(坏死向上扩展到割面) 生理的一个主要外部诱因。在这些协迫的作用下,细胞与分子研究显示,橡胶树生理失调是导致树皮坏死迅速扩展的原因。在这些协迫的作用下,在胶树芽接部位的细胞破裂,释放极具扩散性的高浓度氰化物。在患病胶树的韧皮部生氰和解氰活动的极不协调,以及氰化物的释放,导致其周围的细胞受到毒害。最后, 这样一种多学科的研究方法为由协迫诱导的多因素生理病害研究提供了一个完整的新模式。     

云南东川华山松健康树皮中矿质元素的测定

采用高压硝化罐法硝化样品,用ICP-OES测定了健康华山松树皮中Ca、Mg、K、P、Fe、Mn、B、Zn8种矿质元素含量,同时用半微量法测定了Ag等42种元素,结果表明:(1)健康华山松树皮中Ca>B>K>Fe>Mg>P>Mn>Zn。(2)半微量法测定的42种元素中证明了元素Se的存在,没有测定到Ho、Tl、Pt、Tm。     

Tree bark as a non-timber forest product: The effect of bark collection on population structure and dynamics of Garcinia lucida Vesque

A 2-year demographic field study was carried out on the understorey tree Garcinia lucida in the humid Atlantic forests of South Cameroon. The bark and the seeds of the species are exploited for medicinal purposes and palm wine processing in West and Central Africa. The bark is often removed over almost the entire circumference of the stem, leading to high mortality rates. The goal of the study was to assess the impact of bark harvesting on population structure and dynamics, in order to obtain an indication to what extent the actual harvesting practices can be sustained for longer periods, and to provide information on the future availability of the resource. Comparison of populations that had been subject to different harvest regimes allowed assessment of the effects of G. lucida bark harvesting on population stand structure. In lightly exploited populations, unharvested individuals represented more than the half of the trees (>10 cm DBH), while this was only one-third in heavily exploited stands. The percentage of dead exploited trees (>20 cm DBH) was more than 40 and 70%, for lightly and heavily exploited populations, respectively. This reflects the high intensity of bark harvesting, mainly directed at large trees. For the assessment of bark harvesting on population dynamics, we constructed matrix models for each of the three common bark harvest practices: (1) partial debarking of stem, (2) ring-barking trees and (3) felling trees at approximately 1 m height above ground level to extract bark. For all harvest practices, the asymptotic population growth rates (λ) were not significantly different from 1 indicating that populations were neither growing nor decreasing in size. Nevertheless, model projections showed that the stock of available trees decreased. Under an annual regime of partial debarking of all trees >10 cm DBH, the amount of harvestable trees gradually declined and reached 50% of the initial size after 20 years. For ring-barking and felling trees, the projections showed a sharp drop in the amount of harvestable trees directly after the start of the simulations, and the amount continued to decline below 4% of the initial size under an annual harvest regime. Even after a long time, populations did not recover to their pre-harvest numbers. The stable size of harvested populations predicted by λ values suggest that current harvest practices of bark do not jeopardize the future existence of G. lucida populations. However, as the frequently applied harvest practices of ring-barking and felling strongly reduced the stock in our simulations, commercial bark exploitation cannot be sustained over long periods. Nevertheless, as long as populations can recover from the loss of exploited individuals, by continuous recruitment, there is still prospect for sustained bark extraction.