弧结毛瓢虫对铁杉球蚜取食量的测定

弧结毛瓢虫（Ｓｃｙｍｎｕｓｓｉｎｕａｎｏｄｕｌｕｓ）是近年研究发现的一个新种,其取食量的研究未见报导。弧结毛瓢虫属瓢虫科小毛瓢虫属的小型瓢虫,主要取食铁杉球蚜,是控制铁杉球蚜的重要天敌。为了获取弧结毛瓢虫取食铁杉球蚜的生物学资料,１９９７年７月在宝兴...     

樟白轮蚧的四种天敌瓢虫检索表

红点唇瓢虫、湖北红点唇瓢虫、细缘唇瓢虫、中原寡节瓢虫是樟白轮蚧 （ Ａｕｌａｃａｓｐｉｓ ｒｏｓａｒｕｍ ） 的４ 种捕食性天敌, 本文以检索表形式区分它们的成虫和幼虫。     

黄山松上小鞋孢盘菌属一新种*

本文报道在安徽省黄山风景区黄山松上发现的小鞋孢盘菌属（斑痣盘菌目）一新种──中华小鞋孢盘菌（ＳｏｌｅｅｌｌａｃｈｉｎｅｎｓｉｓＹ．－ｒ．Ｌｉｎ，Ｚ．Ｌｉ＆Ｓ．－ｍ．Ｙｕｓｐ．ｎｏｖ．）。对该种作了拉丁文及汉文描述和图解。主模式标本保藏于安徽农业大学森林保护教研室。     

四川大渡河流域不同地点铁杉林瓢虫科多样性比较

文章首次报道了四川大渡河流域的铁杉林瓢虫科种类、数量及发生时间.在3个地点的铁杉林中,共采集到瓢虫48种.对斑小瓢虫Scymnus geminus、华山松小瓢虫S.huashansong、马蹄毛瓢虫S.lycotropus、宁陕毛瓢虫S.ningshanensis为首次在四川报道.3月到11月均可采集到瓢虫成虫,以5月(22种)、6月(25种)和7月(24种)为最多.幼虫出现主要集中在5月.羊厂沟铁杉林是以阔叶为主的针阔混交林,其瓢虫的物种丰富度指数、多样性指数、均匀度指数均远远高于泥巴沟和驷马桥.泥巴沟和驷马桥同属于针叶树占优势的针阔混交林,林内瓢虫科物种丰富度指数较低,但种类优势度高.三地瓢虫组成相似性均处于较低水平.     

毛金竹开发利用研究

毛金竹开发利用研究欧阳训荣刘宝财（江西省遂川县五指峰林场３４３９０９）关键词：毛金竹抚育改造效益分析毛金竹Ｐｈｙｌｏｓｔａｃｈｙｓｎｉｇｒａｖａｒ．ｈｅｎｏｎｉｓ（Ｍｉｌｆ）ＳｔａｐｆｅｘＲｅｎｃｌｅ，又名小毛竹，隶属禾本科竹子亚科刚竹属，广泛分布于...     

A Study on the Soil Water Balance of Protective Forest Ecosystems in Loess Areas in China

ＡＳｔｕｄｙｏｎｔｈｅＳｏｉｌＷａｔｅｒＢａｌａｎｃｅｏｆＰｒｏｔｅｃｔｉｖｅＦｏｒｅｓｔＥｃｏｓｙｓｔｅｍｓｉｎＬｏｅｓｓＡｒｅａｓｉｎＣｈｉｎａＣｈｅｎＬｉｈｕａ，ＹｕＸｉｎｘｉａｏＣＯｌｌｅｇｅｏｆＳｏｉｌａｎｄＷａｔｅｒＣｏｎｓｅｒｖａｔｉｏ...     

七种泡桐生长点的培养

为了探索泡桐种类生长点（茎尖）培养的最佳培养基，从泡桐属７种中的每种选择１－２株成年树，取其０．５ｍｍ长的生长点，分别培养在４种无菌培养基中。这４种培养基是：Ｍｕｒａｓｈｉｇｅａｎｄｓｋｏｏｇ（ＭＳ）培养基、阔叶树（ＢＴＭ）培养基、木本植物（ＷＰＭ）培养基和Ｗｏｌｔｅｒａｎｄｓｋｃｏｇ（ＷＳ）培养基。在ＭＳ、ＢＴＭ和ＷＰＭ培养基中培养３０天后，外植体成活率最高的是毛泡桐、光泡桐和海岛泡桐。在ＭＳ和ＢＴＭ培养基中成活率最低的是白花泡桐和Ｐ．ｃｏｒｅａｎａ。在ＭＳ和ＢＴＭ培养基中成活申为零的是台湾泡桐和兰考泡桐。在相同的ＢＴＭ和ＷＰＭ培养基中３０天的过程，发芽率较大的是毛泡桐和光泡桐。从成活的外植体上面芽的发育数目和芽的平均长度来看，ＭＳ和ＢＴＭ是最佳培养基，但在种与种之间以及植株个体之间．其生长点的成活率有所不同。     

中国茎蜂科分类研究──Ⅴ．华茎蜂属及其近缘属（膜翅目：茎蜂科：哈茎蜂族）

记述了中国哈茎蜂族３属６种，含２新种；裂板华茎蜂（Ｓｉｎｉｃｅｐｈｕｓｉｎｃｉｓｕｓｓｐ．ｎｏｖ．）及红腹华茎蜂（Ｓｉｎｉｃｅｐｈｕｓｒｕｆｉａｂｄｏｍｉｎａｌｉｓｓｐ．ｎｏｖ．）．新种模式标本保存于中南林学院环境与资源系．编制了华茎蜂属及尾茎蜂属已知种检索表．     

山林水环境水生昆虫丰富度及多样性初探

水生昆虫（Ａｑｕａｔｉｃｉｎｓｅｃｔｓ）是自然环境的重要成员，参与构成生物多样性（Ｂｉｏｌｏｇｉｃａｌｄｉｖｅｒｓｉｔｙ）。经对昆明市郊山林水环境设８个样点调查，共获水生昆虫５目１５科３０种。其中半翅目（Ｈｅｍｉｐｔｅｒａ）和鞘翅目（Ｃｏｌｅｏｐｔｅｒａ）为两大优势类群。样点Ｓ一Ｖ和Ｓ一Ⅵ水生昆虫种类较多，物种丰富度（Ｓｐｅｃｉｅｓａｂｕｎｄａｎｅｃ）依次为２１和１９；样点Ｓ一Ⅶ和Ｓ一Ⅵ的半翅类昆虫多样性指数即Ｓｈａｎｎｏｎ一Ｗｉｅｎｅｒ指数较大，分别是１．５３００和１．５１２２。     

扶绥中东金花茶新种

扶绥中东金花茶新种梁盛业（广西林科院）ＣａｍｅｌｌｉａａｃｈｒｙｓａｎｔｈａＣｈａｎｇ＊ｅｔＳ．Ｙ．Ｌｉａｎｇ，ｓｐ．ｎｏｖ．Ｓｕｂｇｅｎ．ＴｈｅａＣｈａｎｇ，Ｓｅｃｔ．ｃｈｒｙｓａｎｔｈａＣｈａｎｇ，Ｓｅｒ．ｃｈｒｙｓａｎｔｈａｅＣｈａｎｇ．Ｓｐｅ...     

长苞铁杉群落结构特征研究

长苞铁杉属于珍稀濒危植物，被列为国家Ⅲ级保护植物。在样地调查材料的基础上，对福建省天宝岩自然保护区珍稀植物长苞铁杉群落结构、群落数量特征、种群动态进行了深入分析与研究。并对长苞铁杉濒危机制及保护措施进行了探讨，为长苞铁杉林的保护提供了理论依据。     

珍稀濒危植物长苞铁杉种群密度效应模型

植物种群的调节是一个多因素的复杂过程,通过对种群的出生、死亡和生长等过程的控制,使种群的数量维持在生境可以容纳的最大水平上.尽管影响种群动态的因素可分为密度制约因素和非密度制约因素,但在植物中,尤其对木本植物,主要是密度制约起着种群调节与控制的作用,这种调控的过程反映了种群对群落结构及相应环境条件的适应与利用,主要表现为植物种群密度效应(江洪,1992).种群密度效应一直是种群生态学领域研究的热点.前人在研究植物种群密度拥挤效应规律时,提出了大量理论或经验的表达式(Yada et al.,1963;唐守正,1993;方精云,1995;Hozumi,1977;1983;John et al.,1994;张大勇等,1985;吴承祯等,2000c;2000d;安藤贵,1968;洪伟等,1996;陈辉等,1992),反映了植物种群数量动态受多种限制因素影响,如有限的资源、空间以及种内、种间植物个体对资源的竞争,导致种群数量发生变化,即为密度效应     

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.