长白落叶松最佳杂交组合选择的研究

利用长白落叶松种子园１０、６、１１２、４Ｃ、４Ｈ和１４等无性系，采用正、反交制种设计，共３０个组合。１９８６年育苗，１９８８年造林，１９９４年调查分析．６个无性系和３０个组合的一般配合力、特殊配合力以及反交效应的差异，均达到了极显著水平。一般配合力较好的有１４和１０号；特殊配合力较好的有６×１１２、６×１４、４Ｃ×４Ｈ、１０×４Ｃ、１０×１１２、１０×１４、４Ｈ×１４、６×４Ｈ、４Ｃ×１４、１１２×４Ｃ；反交效应较好的有６×１１２、１０×１４Ｃ、４Ｃ×４Ｈ、６×１４、１１２×４Ｈ、４Ｃ×１４、１１２×１４、１１２×４Ｃ．     

接干和施肥对不同初植苗高泡桐幼树主干生长影响的研究

研究了接干和施肥对苗高为３．０、３．５、４．０、４．５、５．０ｍ初植的３年生和４年生泡桐幼树生长的影响。结果表明,１次接干能明显促进苗高为３．０、３．５ｍ苗的３年生泡桐幼树的高生长;２次接干能明显促进苗高为４．５ｍ的４年生泡桐的高生长,并且苗高为４．０、４．５、５．０ｍ的４年生泡桐幼树的高和胸径生长量都明显比３．０ｍ和３．５ｍ苗的大;施肥能明显促进苗高为４．５、５．０ｍ的１次接干泡桐幼树的高生长。２次接干处理后,对高为４．０ｍ的苗培育高干良材（主干达６．０ｍ以上）有一定的保障。     

银中杨栽培技术研究

银中杨系人工杂交新品种。应用数学方法进行分析、筛选，提出了造林的具体指标和措施。研究认为，应选择充分熟化的立地条件，采用全面整地方式，应用二年生根桩及二根一干、二根二干苗造林；造林密度根据材种不同可采用２ｍ×４ｍ、３ｍ×４ｍ及４ｍ×４ｍ；营养元素合理施肥的比例是：４Ｎ：１Ｐ：３Ｋ：４Ｃａ：１Ｍｇ；银中杨与胡枝子、云杉混交具有促进生长作用。     

2002年《森林与人类》杂志总目录

■扉页经典热带雨林在消失１．１“献给地球的礼物”２．１爱鸟周———中国鸟的节日４．１我来自森林１１．１美丽的感动１２．１■本刊特稿中国森林多灾多难２．５又一只东北虎走了３．４博亚保水剂：为绿色输送甘泉３．８百位母亲，乳汁接力拯救金丝猴４．４生命之歌———一个法国女孩和她的野生动物世界６．４１行走在绝望与希望的现场———卢彤景和他的“生态告急摄影”７．４地球峰会的叹息与歌咏１０．４伤口来自历史的深处———塔克拉玛干沙漠环境问题探源１１．４■绿色论坛森林人工化的忧思１．９菇价涨后的思索１．１０人是自…     

井冈山的特有植物

井冈山的特有植物刘仁林（江西省井冈山自然保护区３４３６００）井冈山已发现特有植物２０种（含变种），隶属于１４科１７属（详见表１），其中种子植物１０科１３属１６种，蕨类植物４科４属４种。在种子植物中，落叶植物４种，常绿植物１２种，均属木本植物。按照Ｗｈ...     

Rhizoctonia solani AG4同一融合群内不同分离物对杉苗致病力的研究

ＲｈｉｚｏｃｔｏｎｉａｓｏｌａｎｉＡＧ４同一融合群内不同分离物对杉苗致病力的研究朱天辉（四川农业大学林园学院）ＲｈｉｚｏｃｔｏｎｉａｓｏｌａｎｉＡＧ４是杉苗猝倒病的主要病原［７］，多在４～６月危害，因发病时期不同可出现４种症状类型［３］。此病原是一种...     

国内木材市场行情

东北木材市场价格行情１９９９年１１月８日单位：元／ｍ３品　　名规　格等　级价格红松原木红松原木白松原木白松原木落叶松原木水曲柳原木水曲柳原木水曲柳原木柞　　木椴　　木杨　　木４ｍ×２６～４０ｃｍ５～６ｍ×２６ｃｍ以上４ｍ×２６～４０ｃｍ５～６ｍ×２６ｃｍ以上４～６ｍ×２６ｃｍ以上４～５ｍ×２６～２８ｃｍ６ｍ×２６～３８ｃｍ４～６ｍ×４０ｃｍ以上４～６ｍ×２６～４０ｃｍ４～６ｍ×２６～４０ｃｍ４～６ｍ×２６～４０ｃｍ特　选特　选特　选特　选特　选特　选特　选特　选特　选特　选特　选９００～１２５０…     

国内木材市场

东北木材市场价格行情１９９９年１０月８日单位：元／ｍ３品　　名规　格等　级价格红松原木红松原木白松原木白松原木落叶松原木水曲柳原木水曲柳原木水曲柳原木柞　　木椴　　木杨　　木４ｍ×２６～４０ｃｍ５～６ｍ×２６ｃｍ以上４ｍ×２６～４０ｃｍ５～６ｍ×２６ｃｍ以上４～６ｍ×２６ｃｍ以上４～５ｍ×２６～２８ｃｍ６ｍ×２６～３８ｃｍ４～６ｍ×４０ｃｍ以上４～６ｍ×２６～４０ｃｍ４～６ｍ×２６～４０ｃｍ４～６ｍ×２６～４０ｃｍ特　选特　选特　选特　选特　选特　选特　选特　选特　选特　选特　选９００～１２５０…     

西南木材林产品交易市场产品报价表

西南木材林产品交易市场产品报价表品名规格价格缅甸柚木方材２．６ｍ×３０ｃｍ以上７４００元／ｍ３西楠桦原木４ｍ×４０ｃｍ１２００元／ｍ３樱桃原木４ｍ×４０ｃｍ１３５０元／ｍ３云冷杉原木４ｍ×４０ｃｍ９５０元／ｍ３有节云冷杉原木４ｍ×６０ｃｍ以上...     

银杏核用农家品种的筛选

以大粒，早实，丰产，质优为标准，选出“魁铃”，“团峰”，“魁金”和“新宇”４个银杏核农家品种，这４个农家品种母树均为８０年以上的嫁接时，单核重在３．０ｇ以上，魁铃高达４．０ｇ，苗木嫁接后３～４年开始结果，魁铃接后５年产量达４１ｋｇ／６６７ｍ＾２，是对照新村５＾＃的４．６倍。其果实生理品质也均优于或相当于新村５＾＃。     

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。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.     

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.