生态园林绿地建设中应用树木与草坪效果对比分析

本文从树木与草坪在用水量、观赏时间、造价、管理成本和环保上的 5项指标进行对比 ,论述了风沙、干旱地区的绿地建设应该是树木为本 ,花草点缀 ,乔木为主 ,灌木为辅的原则。     

桉木基复合材料研究进展

桉树作为我国主要的人工林树种之一,具有品种多、生长速度快等优点,在缓解我国木材供 需矛盾上发挥了重要作用。由于桉木存在高生长应力、节疤、易变形开裂等劣势,目前工业上主要用作 纸浆、纤维板或胶合板和单板层积材的芯板,其利用方式单一,附加值较低。近年来研究者们以桉木与 塑料、竹材等材料为原料制备复合材料,展现出良好的尺寸稳定性、力学性能、阻燃性、抗菌性等性能, 有效地提高了桉木的利用价值,拓宽了桉木在人造板、集装箱等领域的应用。文章分别介绍了桉木 / 塑 料、桉木 / 竹、桉木 / 水泥、桉木 / 无机物 4 种复合材料,并对其制备工艺、性能等方面的研究进展进行 综述。     

长白山北坡针叶林带蛾类多样性

2003年6月至2006年9月,对长白山北坡针叶林蛾类做了较全面的调查,针叶林带蛾类种类共计12科,118种,其中夜蛾和尺蛾是北坡针叶林带蛾类的优势类群,各月份蛾类组成及数量差异较大,7月份蛾类的多样性指数、物种丰富度和个体数量都最高,6月份蛾类的多样性指数、物种丰富度和个体数量最低,多样性指数与均匀度不一至,相关系数为-0.15,不同月份的蛾类相似性系数很低。     

浙江风水林类型、特点及保护管理探讨

浙江风水林主要包括村落风水林、坟园墓地风水林、寺庙风水林等3种基本类型。阐述了浙江风水林的历史发展过程及浙江先民对风水林的保护管理,总结了浙江风水林的类型及基本特点,并提出风水林的保护管理对策。     

Farms in the black forest of Baden-Württemberg: A historical review

Today the Black Forest is an internationally renowned tourist region in Germany. For centuries the Black Forest remained as a low mountain range regarded as not suitable for settlement due to its unfavourable climatic conditions and difficult terrain. Clearing the dense forests and settlement therefore started at a historically late stage compared to other regions of Germany, about 1000 years ago. Due to the special conditions in this area, the structure of the settlement had to be quite different to those landscapes with more favourable conditions for agriculture. A single-farm settlement developed, farms situated 200 to 400 m away from each other, surrounded by meadows, agricultural land and forests and owned by the farmer’s family. This structure has remained in some areas until today; in other areas different types of settlement took place, and great changes occurred during history. A special type of agroforestry — a slash-and-burn-management of forests — also took place 150 to 200 years ago.     

Establishment and growth of coniferous seedlings in an altered forest floor after long-term exclusion of deer

We evaluated differences between the forest floors and the establishment and growth of coniferous seedlings in fenced (13 years) and unfenced plots on Mt Ohdaigahara where the sika deer (Cervus nippon) population density is high. Large coniferous seedlings (height > 0.05 m) were less abundant in the unfenced plot, as a result of deer browsing. Small coniferous seedlings (height < 0.05 m), however, were more abundant in the unfenced plot, where most seedlings of Abies homolepis were found on bare ground and those of Picea jezoensis var. hondoensis were found on buttresses and fallen logs. The large area of bare ground in the unfenced plot was caused by deer browsing. Deer therefore have an indirect effect on the emergence and growth of small coniferous seedlings by modifying the forest floor.     

小陇山林区日本落叶松人工商品林抚育间伐技术及经济效益研究

通过分析，确定了小陇山林区日本落叶松人工商品林抚育间伐的时间，抚育间隔期及抚育强度，预测了抚育间伐的经济效益。     

42种树叶氨基酸组成的研究

本文研究了中国42种针、阔叶树种树叶中18种蛋白质氨基酸的含量和组成在不同科、属、种之间和不同立地条件下,不同的生长季节进行了比较和探讨。为了进一步研究它们的利用价值,着重研究了与部分粮食和肉类中蛋白质氨基酸组成之间的差别。阔叶树树叶中总的蛋白质氨基酸含量约为针叶树树叶2—3倍。所有树种的树叶蛋白质氨基酸的组成趋势基本相似,树叶中含量较高的氨基酸有天门冬氨基酸、谷氨酸等8种。树叶中总的氨基酸含量高于粮食2—3倍,而且树叶中蛋白质氨基酸的组成趋势与粮食和肉类不完全相同,特别是人和动物体内不能自身合成的8种必须氨基酸的含量分别为高粱、玉米的3倍,麦麸的2倍,与肉类相比,树叶中亮氨酸和苯西氨酸,占蛋白质氨基酸总量百分比高出4—5倍。结果表明,阔叶树叶是优良的饲料添加剂。     

谈评等中针叶材活节检量

本文针对GB／T114－1995《原木检验》标准中，有关针叶树材的活节，检量颜色较深，质地较硬部分（似黑眼珠）的尺寸问题，认为颜色较深、质地较硬是构造特征，节子尺寸应含最外圈年轮。检量似黑眼珠不符合国际惯例。     

凉水自然保护区森林演替序列土壤水溶性碳水化合物质量分数特征1）

为探讨不同森林植被类型对土壤中碳水化合物的影响,以凉水自然保护区原始红松针阔混交林和阔叶次生林为对象,对土壤碳水化合物进行研究。结果表明：随着土层深度的增加,两种植被类型下土壤中碳水化合物质量分数都有递减的趋势。在0～10 cm和＞10～20 cm土层中,阔叶次生林土壤碳水化合物质量分数显著高于原始红松针阔混交林土壤。在2种碳水化合物提取方式下,热水（100℃）提取的碳水化合物质量分数显著高于常温（25℃）提取的（ p＜0．05）,且都是随着土层深度增加,碳水化合物质量分数降低。浸提液在波长254 nm和280 nm下的吸收值与相应提取的碳水化合物质量分数都呈显著正相关。