齐心协力忙造林

2003年，我省林业生产走过了不平凡的一年。林业工作在国家林业局和省委、省政府的关心下，在各级党政领导的支持下，经过全省广大林业干部职工的共同努力，林业建设取得了硕果累累的成绩。全省森林覆盖率达到53．67％，拥有立木蓄积量3．23亿立方米，实现林业总产值362亿元，完成人工造林41．47万公顷，义务植树1．2亿株，是我省历史上造林任务最多、资金投入最大的1年。在国家林业局组织的全国营造林实绩综合核查中，综合得分99．53分，造林质量居全国第一，赢得了造林质量“七连冠”的美誉。     

实施中德合作造林项目促进延安林业可持续发展

中德合作陕西二期延安造林项目，从2001年正式启动实施至今，已完成人工造林15519．69公顷。完成计划任务18000公顷的86．2％。经省、市项目监测中心监测，合格面积累计达15205．86公顷，合格率为97．9％。中德合作造林项目的建设。填补了延安林业史上利用外资的空白，对延安的林业机制、管理模式的转变，技术刨新以及可持续发展，产生了深刻的影响。     

水保工程是提高内蒙古黄土丘陵造林质量的有效途径

内蒙古的黄土丘陵分布区，降水量少，蒸发量大，植被稀疏矮小，水土流失严重，土壤含水率为５％，造林成活困难，成活率在４０％以下，造林质量差，若不配以水保工程措施，则不易成功。因此，必须进行水保工程设计。现将水保工程设计的方法及造林应注意的问题作以介绍。造林配以水保工程后，提高了造林质量，经调查，１９９１、１９９２、１９９３年的造林成活率均为８５％。工程措施、生物措施完成后的第五年，林草覆盖率可达７０％以上，基本上改变了生态环境，经济效益有明显提高。以凉城县双古城乡小夭沟行政村为例，全村总面积２２８８公顷，其中造林面积４１２公顷，森林覆盖率为１８％，１９８３年林业收入近万元、人均纯收入３１９元，而１９９３年林业收入达到１１万元、人均纯收入７００元，人民生活有显著改善。     

耀州区林业生态工程建设初显成效

1998年以来，耀州区委、区政府抓住国家实施西部大开发战略和山川秀美工程的机遇，以林业生态工程建设为重点，精心组织，强化管理，讲求质量，注重效益，六年人工造林保存面积31万亩，占全区人工造林保存总面积的56．9％，森林覆盖率由九十年代初的28．4％提高到38．2％，境内的漆水河、沮河、赵氏河、清峪河、浊峪河五大流域内林草覆盖面积达到75％以上，水土流失得到有效控制，一个山川秀美的新耀州展示在人们眼前。     

浅析影响造林质量的社会因素

随着我国大规模植树造林活动的开展，特别是《中共中央国务院关于进一步加快林业发展的决定》的出台，如何提高造林质量、确保工程建设的有效实施，已成为各级政府和林业主管部门首要解决的问题。作根据多年来从事造林工作的实践，主要针对影响造林质量的思想观念、造林机制、苗木的选择供应、效益补偿机制、林业产业链、质量监管体系等社会因素进行了阐述和分析。     

我国首个碳汇项目造林工程全面完成

2005年底，赤峰市林业对外项目管理办公室组织技术人员，对敖汉旗实施的“碳汇”国际合作“中国东北部敖汉旗防治荒漠化青年造林项目”工程进行实地监测，结果表明：2005年春季营造的2万亩杨树、踏郎混交林合格率为100％。同时，对秋季完成的2．5万亩造林项目进行实测，结果显录造林地块、模式、树种均符合项目设计要求，至此，该项目已全面完成造林任务。     

让世行贷款造林成为窗口工程

新邵县从1995年开始实施世界银行贷款造林项目。通年5年来卓有成效的工作，取得了令人瞩目的成绩。累计完成营造林1750．4公顷，为计划面积的175％；完成总投资525万元。经过多层次严格检查，历年新造林成活率均在95％以上，造林面积保存率100％，达到了速生丰产林标准，项目营造林质量在全省名列前茅。据专家测算，项目建成后，可新增森林蓄积量20．2万立方米，楠竹115万根，实现产值7210万元，投入与产出之比为1∶13．7，且有力地促进了全县科技兴林和林业管理水平的提高，产生了很好的示范和辐射作用。世行贷款造林是迄今新邵林业投资最…     

河南省世行造林项目管理的主要措施

1990年以来,河南省先后利用世界银行贷款实施了4个大型林业外资造林项目,利用世界银行资金达4．6亿元人民币。20年的实践积累中,不断总结项目实施管理过程的经验,形成了项目管理的鲜明特点,对提高林业造林项目的整体实施质量起到了重要的推动作用。     

2004年我国林业建设发展势态良好

最新统计资料显示，2004年我国共完成营造林面积716．7万hm^2，为年计划的96％；实现林业产业总产值6076．77亿元；林业投资完成额348．22亿元。六大林业工程实施顺利，2004年完成的造林面积为510．71万hm^2，占全部造林面积的84．18％。     

影响我国人工造林质量的因素及技术措施

随着重大林业工程的实施和国家对造林的投入迅速增加,造林质量倍受关注。文章分析和总结了我国造林质量中存在的问题,提出相应的对策措施。     

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.