海南岛油茶资源果实经济性状评价

为了高效利用海南岛内丰富的油茶遗传资源,于2014年10月和2015年11月对海南岛内现有油茶树龄为10 a以上的29个样地进行了连续2 a的采果、测量与分析,通过果实生产性状和种子油脂质量性状2个功能结构层共9个指标层构建了海南岛油茶资源果实经济性状评价指标体系,采用均方差综合分析方法进行综合评价。评价结果表明:QZ03号样地综合表现最佳,BS01、QH02、CM02样地的生产性状表现相对较好,DA03、BT02、WZS02样地的油脂质量相对较高。     

油茶知识产权保护管理有新要求

国家林业局科技发展中心在湖南耒阳召开的油茶知识产权保护与管理工作座谈会强调,加强油茶知识产权保护是保障国家粮油安全、保护国家战略性资源及推动油茶自主创新、提升油茶产业核心竞争力的迫切需要,深入研究加强油茶知识产权保护与管理的措施和机制,促进油茶产业健康可持续发展。     

海南岛降香黄檀种质资源调查与分析

为了掌握海南岛降香黄檀种质资源的分布情况,以更好地保护、开发和利用此资源,对海南岛降香黄檀种质资源进行了调查、分析,并针对降香黄檀可持续发展提供相关的建议。     

海南岛西南桦的地理分布及其种质资源现状

本文论述了海南岛内西南桦(Betula alnoides Buch—Ham．)天然林水平分布和垂直分布的基本特点：介绍了西南桦在海南岛的种质资源现状及存在问题，为海南岛的西南桦天然林保护与人工林发展提供科学依据。     

尖峰岭野生园林植物资源的保护与利用

本文介绍海南岛尖峰岭自然保护区适宜园林发展的野生植物资源的五个种类，指出目前在发展利用中存在的四个问题，提出了保护、发展和合理利用的四条具体建议。     

江苏油茶种质资源调查与分析

对江苏油茶种质资源的地理分布、生长状况、群落特征等进行调查,测定了初选优树的果实、产籽量、油脂含量及品质等指标。结果表明,江苏油茶资源零星或小片分布于乔木林下,没有油茶纯林群落;南京溧水区、江宁区和连云港市云台区等为油茶栽培面积较大的区域,位于油茶分布北界连云港云台山的油茶生长良好,耐寒性强,具有油茶抗寒种质资发掘利用价值。通过调查初选49个油茶优良单株,其中6个单株的出籽率、出油率等指标达到国家油茶良种标准。     

海南油茶种实数量性状多样性评价

为给海南省油茶资源分类及资源开发利用提供参考依据,以分布于海南省9个县(市)20个乡镇的21个老油茶林分为研究对象,对其油茶种实的10个数量性状指标进行了观测,并对其种实数量性状的变异系数、差异性、相关性及多样性指数进行了分析。测定结果表明:海南油茶的平均单果质量为42.46 g,最大单果质量为156.87 g,其单果质量较集中分布于28.21~39.07 g这一等级内,其平均鲜出籽率为32.87%,最高可达52.00%,大部分在25.45%~39.61%的范围内;海南油茶种实数量性状变异大,大多数性状表现出显著或极显著的差异,10个种实数量性状的平均变异系数为29.36%,而其果实横径、果实纵径和果形指数的变异系数均小于20%;其种实数量性状类型丰富且均匀度较高,平均多样性指数为2.749 9。分析结果表明:部分海南油茶种实性状间存在显著相关性;海南油茶资源在果实性状方面与高州油茶Camellia vietnamensis较为接近,海南油茶可能是高州油茶适应海南环境的生态型;海南油茶资源存在丰富的遗传变异,这是海南油茶良种选育的良好种质资源基础。     

辰溪县油茶发展现状与对策

辰溪县油茶栽培历史悠久,资源丰富。本文在调查辰溪县油茶产业发展现状基础上,剖析了油茶现阶段产量偏低的原因和制约油茶产业发展的因素。根据油茶资源特点,将县域内油茶分成了4种类型,并将具有发展潜力的区域分成了4个重点片区。针对不同区域、不同类型油茶林提出了具体技术措施,还就辰溪油茶产业发展问题,提出了相应的政策建议。     

油茶杂交育种试验

为给油茶新品种选育及确定合理的杂交组合奠定基础,利用江西省林业科学院山茶属种质基因库丰富的油茶种质资源,采用有性杂交技术,于2005年选用12个油茶优良无性系、优良农家品种、油茶物种作为亲本,进行了12个不同组合的杂交育种试验,并于2006年10月采收杂交果实83个。通过试验得出不同杂交组合的平均坐果率,初步确定了不同亲本材料之间的杂交亲和力。其中,白皮中子×赣无1组合平均坐果率最高,为90%,表现亲和。     

海南热带珍贵乡土树种保护及其可持续利用对策

立足海南岛丰富的珍贵乡土树种资源现状,对当前珍贵乡土树种在保护与利用过程中存在的基本问题进行分析,提出推进海南珍贵乡土树种资源保护及其可持续发展的基本对策。     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Risk Perception Among Non-industrial Private Forest Owners

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.     

Interactions in decomposition and N mineralization between tropical legume residue components

In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha⁻¹ target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha⁻¹. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹); (2) Lolium perenne L. var. Tove (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m², with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.     

Key Habitats in the Norwegian Production Forest: A Case Study

This study investigated the forest history, structural characteristics, the presence of fungal species suggested to indicate ecological continuity in old-growth forest, and the species composition of saproxylic beetles in 30 old forest ''woodland key habitats'' (WKHs), and compared them with production forest in the same age-class in south-eastern Norway. No statistically significant differences in forest characteristics, community of saproxylic beetles or number of red-listed beetles were found between the WKHs and the production forest, probably owing to a combination of profound long-term logging and a lack of will to delineate sufficiently large WKHs in the one area with significantly less forestry impact. The study indicates the advantage of including forest history information in WKH selection where such data exist, and the importance of restoring habitats in heavily exploited forest landscapes.