海南岛尖峰岭林区昆虫区系——蛱蝶科

在海南岛尖峰岭热带林区中共采到蛱蝶71种,其中热带半落叶季雨林中蛱蝶种数最多,热带山地雨林次之,山顶苔藓矮林最少。在不同的森林植被类型中,有着不同的蛱蝶种类和优势种群。目前已鉴定的61种蛱蝶中,87％分布在东洋区,13％分布在东洋区和古北区。海南岛原与广东大陆相连,两地蛱蝶相似率高达67％。多数蛱蝶其盛期出现在每年5月。     

海南岛尖峰岭灰蝶的区系与生态分布的研究*

在海南岛尖峰岭林区共采集到灰蝶１０３处，其中在热带山地雨林中采到８１种，占尖峰岭灰蝶种数的７８．６４％；分布在东洋区８４种，占尖峰岭灰蝶种数的８１．５５％。亚洲热带区域特有种４０种，中国分布新记录１７种，优势种群１９种。     

海南岛热带森林的开发利用及其在生态平衡中的作用

海南岛热带森林资源是很丰富的,在大的方面来说,主要包括热带珍贵植物资源和热带动物资源等。在植被类型方面,从滨海到中山分布着红树林、砂生草原、稀树草原、多刺灌丛、落叶半落叶季雨林、常绿季雨林、山地雨林、山地常绿润叶林、山地苔藓矮林和热带山地草原等。种类有维管束植物约四千余种,特有种五百多种,经济价值比较高的有六百种以上。其中乔木树种约有九百种左右,列为商品材树种的有四百五十八种,划为特类材的有母生(Homalium hainanense Gagnep.)、坡垒(Hopea hainanensis Mett.et Chun)、     

海南岛尖峰岭林区昆虫区系调查报告(一)

尖峰岭林区的昆虫所采到的标本共有20目约4000余种,其中鳞翅目种类最多,其次为鞘翅目、双翅目、膜翅目、半翅目、直翅目、同翅目等。以蛾类为例,灯诱所得虫种数是夜蛾科、尺蛾科和螟蛾科最多,每虫种平均诱到的虫数是燕蛾科和拟灯蛾科最多。在这当中佩夜蛾和条纹绢野螟是数量最多的虫种。从鳞翅目13个科来看,热带山地雨林中分布的种类最多,以下的次序是热带半落叶季雨林、山顶苔藓矮林、热带常绿季雨林。热带山地雨林中植物种类和灯蛾种类均最多,而热带半落叶季雨林中两者的种类均最少。再从两个森林类型之间植物与灯蛾的共有种来说,亦以热带山地雨林为最多。由此可见,该类型是植物和蛾类昆虫种类组成上的中心,并有向上和向下递减的趋势。一些实例证明,天然林中的害虫,当转入人工纯林后,常发展成灾。热带林区昆虫的特点是种类多,数量少,世代多,无休眠,有滞育。     

西双版纳勐仑地区不同植被类型鸟类季节变化

2015年1—12月,分春、夏、秋、冬4个季度对勐腊县勐仑镇分布的热带季雨林、石灰山季雨林、热带雨林次生林、人工雨林4种植被类型下的鸟类进行调查。结果表明,从横向看,第一季度和第二季度热带雨林次生林的鸟种类最多,第三季度和第四季度热带季雨林的鸟种类最多;从纵向来看,除热带季雨林为第四季度鸟种类最多外,其余3个植被类型均是第一季度的鸟种类最多。因此,受人为干扰少的植被类型鸟的种类和数量较多,第一季度是鸟类的繁殖季节,鸟类活动较频繁,各植被类型下的鸟类被发现的也最多。     

海南岛热带山地雨林林隙及其自然干扰特征

通过对海南岛霸王岭原始热带山地雨林中５３个林隙的调查,研究了海南热带山地雨林林隙的基本特征和自然干扰规律。海南热带山地雨林林隙的形状近似于椭圆形,椭圆的长短轴比率不随林隙的大小而变化,基本上都在１４左右;扩展林隙（ＥＧ）和树冠空隙（ＣＧ）在热带山地雨林景观中的面积比例分别为５３５２％和２５２２％,干扰频率分别为１３４％·ａ－１和０６３％·ａ－１,林隙干扰的返回间隔期约为１６０ａ。海南热带山地雨林中ＥＧ的大小一般变化在３０～５００ｍ２左右,平均约为１６０ｍ２,大多数ＣＧ的大小一般都变化在１５～２００ｍ２左右,平均约为８０ｍ２。大多数的林隙是在４０ａ以前形成的,而１０～３０ａ之前形成的林隙最多。大多数林隙是由１～４株形成木创造的,而由２株形成木创造的林隙最多。林隙形成木通过掘根、枯立、干基折断和干中折断死亡的比例分别是１６８８％,１４２９％,３６３６％和３２４７％,在不同的林隙中可见到形成木这几种死亡形式的不同组合。海南热带山地雨林中的林隙主要是由２０余个树种创造的,其中不仅有第一层的树种,而且还有第二、三层的树种。文章最后以林隙动态理论为基础,对海南热带山地雨林的经营提出了几点建议。     

黄藤生态生物学特性的研究*

热带山地雨林、热带常绿季雨林亚热带常绿阔叶林是黄藤天然分布的主要植被类型，在热带山地雨林和季雨林的不同林型中，黄藤分布密度变化大，１０－１７００株／ｈｍ＾２；黄藤为强萌蘖丛生植物，１－３年生幼藤生长缓慢，３年生植株生长加快，茎长生长量大于１．０ｍ／ａ，４－５ａ开花结果；藤丛由茎长不一的异龄植株所组成，不同长度级的株数分配及其茎长占藤丛总株数的比例具有一定规律：各长度级的藤株数量随长度级的增加而减少     

尖峰岭国家级自然保护区青皮林资源及其垂直分布特征

尖峰岭国家级自然保护区三分区的青皮林是目前海南岛保存最好的林分之一，其生态系统的原生性较强．组成种类繁多，林分结构合理，平均胸径为28．6cm，最大植株胸径达143．3cm，23个样方中有14个样方出现了胸径≥70cm的大乔木；林木蓄积量高达469．773m^3／hm^2，而青皮、细子龙、野生荔枝、盘壳栎等13个种的蓄积量占总蓄积量的45％，其余301个少见种或偶见种的蓄积量只占55％，反映了青皮是热带常绿季雨林生态系统关键种的现实。青皮与细子龙、野生荔枝等的最佳分布海拔在300m～650m之间，它们与向低海拔分布的白茶、翻白叶和向高海拔分布的大叶白颜、青兰、拟核果茶等一道组成了热带常绿季雨林的表征种类。     

马关古林箐自然保护区植物多样性及综合评价

在物种多样性、遗传多样性和生态系统多样性3个层面上论述了古林箐自然保护区植物多样性现状,分析了植物多样性的特征．保护区内热带湿润雨林、季节雨林、石灰山季雨林、山地雨林和南亚热带季风常绿阔叶林、中山湿性常绿阔叶林均有着本区的特点：区系成分复杂而联系广泛,植被类型多样而分布集中,植物种类丰富而密集度大,起源古老而特有种多,具有很高的科学研究和保护价值．     

海南岛霸王岭4种热带森林类型林地土壤养分状况的比较分析

对海南岛霸王岭林区沿海拔梯度自然分布的热带落叶季雨林、热带低地雨林、热带山地雨林、热带山地常绿林4种热带森林类型林地土壤的养分含量进行了比较分析。结果表明:海南霸王岭林区此4种热带森林类型林地土壤的有机质、氮、磷、钾含量差异显著;其土壤养分的有效性较差,土壤养分的总含量位于全国平均水平的中上等级,高于海南全岛土壤养分的平均水平,说明海南岛的原始热带林能较好地保持林地土壤肥力。     

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.     

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.     

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.