松树皮复配基质的理化性质

用<0.5,≥0.5~2,≥2~5mm3种粒径的油松树皮按不同的质量比配成5种基质,以田园土为对照,研究了不同复配基质的理化性质、收缩率和含水量的变化情况,并选出适宜的油松育苗基质。结果表明:油松经过一个生长季后,5种基质的物理性质比较稳定,各项物理指标基本不变或小幅度改变,说明基质物理性质稳定性较好;除pH外,基质化学性质变化幅度较大,但栽培前后5种基质的理化性质均在基质的理想范围之内,说明5种基质适宜做育苗基质。根据基质的含水量、基质收缩率和物理性质主成分分析,基质粒径D≥2~5mm∶D≥0.5~2mm∶D<0.5mm为1∶3∶1的复配基质为最宜育苗基质。     

树皮含量对纤维热磨机能耗与纤维质量的影响

对以杨木为主的纤维热磨试验数据进行统计,分析树皮含量与纤维热磨机能耗、纤维质量之间的关系.结果表明,树皮含量对热磨机能耗与纤维质量产生较大影响,热磨机能耗随着树皮杨木比(简称“皮木比”)的降低而减小,纤维筛分值随皮木比的增加呈现先升后降的趋势;对包装基材和地板基材用纤维板,允许的树皮含量分别为16％和14％,既保证产品质量,又降低原料成本.     

Influence of Bark Pyrolysis Technology on Yield

INTRODUCTION Bark accounts for 10% of a log and there are about 2.5 billion m3 of logs consumed every year all over the world, which produce 250 million m3 of bark. It will bring a huge amount of money if we make good use of the bark as a raw material of industry. Since middle- and small- diameter classes wood of poor quality and remnant products account for an important part of forest resource, we should advance comprehensive utilization energetically and orient it to whole-tree utilizati…     

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.     

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。     

Studies on the abundance, biology and harmfulness of leaf beetles (Coleoptera: Chrysomelidae) in natural bush vegetation in Isparta, Turkey

Leaf beetle occurrence and abundance on certain shrubs and bushes were surveyed during 2002–2003 in several natural habitats of Isparta. The 34 leaf-beetle species collected are listed and classified according to their relative percentage of the total caught and to their associated host plants. In all habitats sampled, leaf beetles showed a preference for plants from the genera Quercus and Crataegus. Some abundant species causing serious damage to their food plants are discussed.     

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。     

落叶松树皮热解油替代部分苯酚合成酚醛树脂胶的研究

为降低酚醛树脂胶(PF)生产成本,提高木材废弃物利用率,利用落叶松树皮热解油部分替代苯酚合成PF胶,探讨其用量对PF树脂胶性能的影响,并进行成本分析.结果表明:落叶松树皮热解油-PF胶具有良好的胶合性能,制备的胶合板可满足GB/T 9846.3-2004中Ⅰ类胶合板的强度要求,且生产成本降低.     

华山松16种小蠹(鞘翅目:象虫科:小蠹亚科)前胃结构的形态学

通过光学显微和扫描电镜技术,对危害华山松的16种小蠹前胃形态结构进行观察.根据前胃板的结构特征可以将16种小蠹前胃分成3个类型,这些前胃形态结构的差异可以作为小蠹分类鉴定的辅助手段,且前胃类型与韧皮部小蠹虫在华山松树干上的空间分布相吻合,华山松韧皮部小蠹前胃结构的特化是适应食物类型(营养的累积和质地)的结果.     

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&#215;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。