桉树地的土壤改良办法

指出了由于桉树具有速生、适应性强以及经济价值高等多种优点,全球的桉树种植量表现为上升趋势,但是,桉树种植中,由于经营管理不善而导致的土壤问题也频繁出现,严重影响了桉树种植的环境效益与经济效益。基于此,对当前部分桉树地土壤存在的问题进行了分析,并提出了桉树地土壤改良的基本原则和办法,以优化桉树种植方式,增强桉树的生长能力,促进桉树种植经济效益的可持续发展。     

长盛不衰的彝州桉树产业--楚雄州桉树产业发展透视

桉树引入云南已经有100多年的历史,楚雄州于1964年引进种植,现已引种桉树树种20余个,桉树种植面积达40万亩,年桉树收入3000万元以上,成为了楚雄州的一大产业.为何桉树在楚雄州长盛不衰呢?笔者总结了以下三条原因:     

赣南桉树林地更新调查研究

指出了随着中国经济的快速发展及木材市场的需求,赣南开始了大规模桉树种植,到2008年时赣南桉树种植面积已达百万亩之多。但低温极端天气造成桉树严重受冻,桉树逐渐枯死,林地被迫更新改造。基于此,对更新后的林地环境、林木生长是否因种植了桉树受影响进行了实地调查,提出了相关的结论。     

海南桉树引种种植成功经验

海南种植桉树对国家、集体、个人、企业都有利益,有许多功绩。海南引种种植桉树88年历史,海南生态环境仍然保持良好生态环境,仍然成为世界人居好环境。海南种植桉树为海南经济发展,保护好天然林,保护好环境,保护好橡胶林,促进平原绿化,增加海南森林覆盖率,丰富森林资源,在短时间内为社会提供大量的木材和薪炭材,保持林业可持续发展,起到非常重要作用。海南种植桉树具有生态效益,社会效益,经济效益。但我们发展桉树同时必须讲究科学规划,适地适树,选用良种,讲究科学种植、合理密度、科学管理,科学施肥,桉树一定能获得高产,又有良好的生态效益。但不能盲目经营,绝不能砍伐天然林,次生林来种植桉树,海南人民有能力把桉树产业这篇文章做得更好。     

桉树病害及其防治

广西平乐县自2002年开始引进桉树种苗种植,截至2008年,全县桉树种植面积已达3万亩。但是,伴随着大面积桉树纯林的营造,桉树病虫害的种类增多且危害程度加重。据调查,目前危害平乐县桉树的病害主要有青枯病、焦枯病、灰霉病、茎腐病、红叶枯梢病等。这些病害已经成为平乐桉树人工林发展的重大障碍。     

桉树病虫害发生现状及防治策略

指出了桉树是现代环境绿化中应用比较广泛的一种植物,不仅对环境具有美化和改善作用,还可以被利用到许多行业中,比如可用于造纸、建筑等。桉树具有其独特的生长习性,目前在我国的种植范围比较广泛,但是,近年来桉树病虫害不断出现,且呈蔓延之势,严重影响了桉树种植的效益。因此,为提高桉树种植经营效益,对桉树的病虫害发生现状与进行了分析,提出了相应的防治策略,希望能够通过做好病虫害的防治来提高桉树的种植效益,为我国桉树的种植与养护作参考。     

影响桉树速生丰产的因素

对2006年在广东省梅县南口镇洋龙村洋塘种植的桉树生长进行调查和分析。结果表明,桉树品种、立地条件和经营措施是影响桉树的速生丰产重要因素。     

桉树无节材修枝技术的实施及效益分析

指出了桉树是广西地区主要的经济性树种,桉树种植为满足市场对木材的需求发挥了重要作用,同时也是国家重要的战略储备。深入阐述了桉树无节枝修枝技术,分析了无节枝修枝技术对桉树种植产生的经济效益,以期不断提高桉树木材的品质,增加广西地区桉树种植的经济收入。     

我国桉树人工林改造技术研究综述

桉树作为速生树种，是国内木材的主要来源，具有较高的经济价值。但前期无节制的大面积种植，且种植技术不规范，导致桉树人工林土壤结构受到破坏、林下植物多样性下降，破坏生态稳定性，不利于桉树人工林的可持续发展。许多研究者对桉树人工林进行改造，以改善桉树人工林生态环境。该文通过查阅近20年国内桉树人工林改造技术研究文献，分析桉树人工林经营存在的问题及其造成的生态后果，评述桉树人工林改造技术，提出今后桉树人工林改造研究方向的建议。     

桉树种植管理技术探讨

指出了加强对桉树种植管理技术的研究,保证桉树的正常生长,获得更多的种植效益,是林业技术人员需要重点研究的课题。结合桉树的生长特性,从垦地备科、育苗、除草、追肥、病虫害防治等方面,对桉树种植管理技术进行了分析和探讨。     

The role of trees for sustainable management of less-favored lands: the case of eucalyptus in Ethiopia

In northern Ethiopia, eucalyptus is the most commonly observed tree species in community and household woodlots. In an environment suffering from biomass and water shortages, erosion and land degradation, fast growing and resilient eucalyptus perform better than most indigenous tree species. Smallholders show a clear preference for eucalyptus poles, which are useful for farm implements and constructing dwellings and fences. In addition, the sale of eucalyptus poles and products has the potential to raise farm incomes, reduce poverty, increase food security and diversify smallholder-farming systems in less-favored areas of Tigray. Despite the potential for eucalyptus to improve rural livelihoods, in 1997 the regional government of Tigray imposed a ban on eucalyptus tree planting on farmlands. The ban was precipitated by concerns about the potential negative environmental externalities associated with eucalyptus, and the desire to reserve farmland for crop production. However, the regional government promotes the planting of eucalyptus in community woodlots, and has recently begun to allow private planting of eucalyptus on community wasteland and steep hillsides. In this paper, we review the ecological debate surrounding the planting of eucalyptus trees. In addition, the economic factors that influence smallholders to invest in tree production are considered. Ex ante benefit–cost analysis based on community and village level survey data from Tigray illustrates that planting eucalyptus yields high rates of return, well above 20% in most circumstances. The effect of variable harvest rates, and the potential costs of decreased crop production when eucalyptus trees are planted on or near farmlands are considered relative to our base case scenario. Based upon the review of the ecological and economic impacts of eucalyptus, we conclude that a policy option favoring the allocation of wastelands for private tree planting offers the greatest opportunity for rural smallholders.     

桉树与环境

本文收集了国内外的一些桉树与环境关系的研究资料。依据众多的研究成果分别从桉树与水分,桉树与土壤养分,桉树水土保持,桉树与其它生物的关系等方面论述了桉树与环境的相互关系;同时阐述笔者对云南发展桉树的看法：桉树每生产单位干物质所消耗的水分和养分少于其它植物,桉树对绿化荒山,保持水土,增加经济收入是有益的。因此,有计划、有步骤地继续在云南发展桉树实有必要。     

桉木基复合材料研究进展

桉树作为我国主要的人工林树种之一,具有品种多、生长速度快等优点,在缓解我国木材供 需矛盾上发挥了重要作用。由于桉木存在高生长应力、节疤、易变形开裂等劣势,目前工业上主要用作 纸浆、纤维板或胶合板和单板层积材的芯板,其利用方式单一,附加值较低。近年来研究者们以桉木与 塑料、竹材等材料为原料制备复合材料,展现出良好的尺寸稳定性、力学性能、阻燃性、抗菌性等性能, 有效地提高了桉木的利用价值,拓宽了桉木在人造板、集装箱等领域的应用。文章分别介绍了桉木 / 塑 料、桉木 / 竹、桉木 / 水泥、桉木 / 无机物 4 种复合材料,并对其制备工艺、性能等方面的研究进展进行 综述。     

中国桉树培育技术百年发展史与展望

近年来,桉树在我国得到快速发展,成为保障我国木材安全的重要树种。但是,支撑桉树快速发展的培育技术还没有得到很好的总结。文中简要介绍了世界桉树引种概况,总结了我国桉树培育技术的发展历史,展望了我国桉树培育技术发展方向,并就影响桉树发展的相关问题进行了探讨。中国桉树培育技术发展可分为4个阶段:一是中华人民共和国成立以前,为桉树零星引种和四旁绿化阶段;二是桉树培育技术的起步阶段,以1954年成立“粤西林场”为标志;三是桉树培育技术的积累阶段,从20世纪70年代后期至1990年形成了造林和抚育技术措施体系的雏形;四是桉树培育技术的快速发展阶段,从1990年以后,桉树造林和抚育技术措施体系基本形成。随着全年造林技术得到发展和完善,现代桉树培育技术体系将逐步形成。     

燃煤烟气脱硫副产物对桉树生长影响的研究

通过盆栽和大田试验,探讨脱硫副产物及以其为原料制作的土壤调理剂对提高桉树生长量的作用,结果表明:(1)适量施用脱硫副产物可有效提高桉树生长量,将其制作成土壤调理剂施用,可进一步提高产量。(2)供试物量过高或过低会导致肥效下降而引起桉树生长量下降。(3)适量施用供试物可有效防治因桉树微量元素供应不足导致的缺素垂梢病。     

陆良县桉树产业发展现状及其与生态环境关系分析

介绍陆良县桉树资源、产品及相关产业发展等桉树产业发展现状,分析人民群众喜爱种植桉树的原因及桉树产业发展的生态、社会及经济效益。阐述桉树产业发展与生态环境的关系,认为按树不是抽水机、不是抽肥机．桉树人工林对植物多样性未造成任何不良影响,也不是导致干旱的原因。并提出了桉树速生丰产林发展对策。     

云南普洱桉树林与天然林植物种类比较研究

随着大面积规模化的种植,桉树人工林结构过于简单,林下植物多样性低的问题不容忽视。通过对普洱地区桉树人工林与同等条件下的天然林植物种类进行比较,桉树人工林群落物种数量流失,多样性下降和外来物种的入侵,说明一旦种植桉树以后,原有的生态系统都完全改变了,单一栽培桉树树种通常都造成了物种多样性的减少。     

Effect of increasing densities of Urochloa brizantha cv. Marandu on Eucalyptus urograndis initial development in silvopastoral system

In silvopasture system, the coexistence of eucalyptus seedlings with other species may result in growth reduction, especially during eucalyptus early development.Therefore, studies elucidating how forage species affect the eucalyptus growth can provide important information for their rational management aiming to obtain the maximum gain of the system. The aim of this work was to evaluate the effect of increasing densities of Urochloa brizantha cv.Marandu in the early development of Eucalyptus urograndis. An experiment was conducted in 20 L pots, in an open and semi-controlled area, during 90 days after planting of eucalyptus. A completely randomized design with four replications was used, in a 6 9 7 factorial system, meaning six evaluation periods and seven densities of U. brizantha: 0(control), 22, 33, 44, 67, 89 and111 plants m^-2. Fortnightly, eucalyptus height, stem diameter and chlorophyll fluorescence(Fv/Fm) were evaluated. At the end of experimental period, the net assimilation rate, stomatal conductance and transpiration rate of eucalyptus plants were determined, in addition to the dry matter of eucalyptus(leaves and stem) and U. brizantha (leaves). In coexistence with 111 plants m^-2, eucalyptus had reduction of 63.9% on total dry matter and 72.7% on leaf area, compared to the control. From the density of22 plants m^-2, U. brizantha negatively interfere significantly the growth of E. urograndis. Up to 8 plants m^-2 there are no reductions greater than 5% in eucalyptus height and stem diameter.     

桉树害虫的生态控制

我国桉树主要用作纸浆材,随着桉树纯林面积的不断扩大,害虫种类与危害程度也呈上升趋势,为此必须以生态学原理和害虫生态控制理论来指导桉树害虫的控制.森林害虫生态控制的主要内涵是建立健康的生态系统,我们对桉树害虫的生态控制采取了选育抗虫树种、适地适树和科学施肥等措施,培育了健康的林分,已经成功地控制了某些害虫对桉树的危害,此举具有经济、社会和生态效益,可持续控制桉树害虫的危害,是今后的发展方向.桉树地下害虫是一类特殊的害虫群体,在造林初期的危害比较严重,此时应针对不同的害虫选用不同的化学药剂来控制其种群密度,施药时要考虑减轻化学药剂对生态环境的不利影响,应采用毒饵诱杀、根部施药等方式.     

Allelopathic effects of eucalyptus and the establishment of mixed stands of eucalyptus and native species

Allelopathic effects of eucalyptus are widely reported and are considered the major factor limiting the establishment of native species in eucalyptus forests. However, reports of the allelopathic effects of eucalyptus are mostly based on laboratory bioassay, not on field trials. In the present study, we conducted field trials to determine the allelopathic effects of eucalyptus and to develop strategies for establishment of mixed stands of native species and eucalyptus. In the field, seed germination and seedling survivorship of native species were determined in the presence and absence of eucalyptus leaf litter or living roots. In the seed germination experiment, seed germination rate of Delonix regia was higher than for Elaeocarpus sylvestris and Tsoongiodendron odorum. Seed germination rates of E. sylvestris and T. odorum were low in both the presence and absence of eucalyptus treatments. The germination rate of D. regia was significantly inhibited by all eucalyptus treatments, but only during the early period. In the seedling establishment experiment, seedling survivorship of E. sylvestris and Michelia macclurel was not inhibited by any treatments, but the seedling survivorship of Schima superba was significantly inhibited by eucalyptus litter addition alone. Seedling height of S. superba and M. macclurel was significantly suppressed when eucalyptus roots were present in treatments, but the seedling height of E. sylvestris was only significantly suppressed by the treatment of roots alone. We propose two strategies for establishment of mixed stands of native species and eucalyptus: (1) direct seed-sowing is effective only for those species (e.g. D. regia) with high germination rates in natural conditions; (2) seedling transplants are more efficient approach for establishing species (e.g. E. sylvestris) with low germination rates. We suggest that mixed plantations of eucalyptus and E. sylvestris can be established by transplanting seedlings of E. sylvestris into eucalyptus plantations.