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本文概述了黔西南桉树造林发展的情况及桉树长势,总结了桉树在黔西南发展的成效,分析了存在的问题,探讨了桉树产业在黔西南的发展前景,据此提出林板一体化发展的设想。 相似文献
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中澳东门桉树项目对我国桉树产业的影响 总被引：1，自引：0，他引：1
本文就中澳东门桉树项目以来我国桉树科技产业的发展进行了总结,并就其对我国桉树科技、产业发展的影响进行了分析,对当前桉树发展中存在的问题提出建议。 相似文献
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永胜县目前有以蓝桉为主的桉树面积4 274hm2,2004年桉油和薪材产值1 471.87万元.介绍了桉树的生物学特点、生长的优点,分析了桉树产业的发展前景,提出了永胜县桉树产业发展对策. 相似文献
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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: 相似文献
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桉树人工林现状及其可持续发展 总被引：19，自引：0，他引：19
桉树是世界公认的速生造林树种,因具有广泛的适应性而得到大力发展,已成为我国林业史上引种最为成功的树种之一,在短周期原料林建设、林—板及林—浆—纸一体化等产业发展中,获得了巨大的经济效益和社会效益。但随着桉树人工林的不断发展,引发了社会的广泛关注和学术界许多争论,对发展桉树的看法褒贬不一,桉树人工林生态问题已成为争论的焦点。本文在综合评价国内外对桉树人工林研究及效益的基础上,认为在成都地区科学经营桉树人工林,不会引起生态问题,并提出了桉树人工林可持续经营的基本思路和对策。 相似文献
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《Forest Policy and Economics》2003,5(1):83-95
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. 相似文献
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M. A. Ferreira T. C. Harrington C. C. Gongora‐Canul R. G. Mafia E. A. V. Zauza A. C. Alfenas 《Forest Pathology》2013,43(2):153-164
Ceratocystis wilt, caused by Ceratocystis fimbriata, has become the most important disease in eucalyptus (Eucalyptus spp. and hybrids) plantations in Brazil. To further our understanding of the epidemiology of this disease, we surveyed eucalyptus plantations in the states of Minas Gerais and Bahia that were known to have Ceratocystis wilt or were thought to have been planted with infected rooted cuttings. There was generally higher disease incidence in the Minas Gerais plantations, which were on former Cerrado forest sites and likely had soilborne inoculum prior to planting eucalyptus. In such plantations, disease incidence was not evident before 20 months after planting but slowly increased up to 50% at 74 months. The symptomatic and killed trees were aggregated, perhaps from uneven distribution of inoculum in the soil. Also, the progression of cumulative disease incidence best fit a monomolecular model, which is typical of soilborne diseases (fixed level of initial inoculum with little or no secondary inoculum during the crop rotation). However, plots where some trees had been harvested during the rotation showed very high levels of disease incidence in the sprouts that arose from stumps, suggesting secondary spread of the pathogen on harvesting tools or machinery. Most of the Bahia plantations were on pastureland prior to eucalyptus cultivation, and the pathogen was likely introduced with infected nursery stock. In such plots, symptoms were evident as soon as 7 months after planting, and most of the mortality occurred within 12 months. The diseased trees on former pastureland sites were sometimes aggregated within planting rows, suggesting that bunches of infected nursery stock were planted together within the rows. Care should be taken in planting disease‐free planting material and spreading the pathogen on tools, but on sites with soilborne inoculum, use of resistant clones may be the only management option. 相似文献
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中国桉树培育技术百年发展史与展望 总被引：1，自引：0，他引：1
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。 相似文献
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桉树营养砖育苗试验结果表明：黄心土与火烧土比例为４∶１，每１００ｋｇ土加施过磷酸钙０．９ｋｇ，不施饼肥、尿素、氯化钾的配方对桉树育苗有促进作用。 相似文献
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Michel Anderson Almeida Colmanetti Allan Lopes Bacha Pedro Luis da Costa Aguiar Alves Rinaldo Cesar de Paula 《林业研究》2019,(2):537-543
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. 相似文献
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将磷肥、尿素和桉树专用肥3种肥料分为3个水平,对4个不同初植密度广林9号桉树幼林进行施肥处理。采用方差分析方法分析了不同施肥处理及不同初植密度对桉树幼林生长的影响。结果表明：不同施肥种类及施肥量对广林9号桉幼林生长差异显著,桉树专用肥的影响极显著,尿素影响显著,磷肥影响不显著,其中尿素随施用量的增加对苗木生长存在抑制作用;桉树专用肥随施用量的增加对苗木生长有明显促进作用。不同初植密度的1年生广林9号桉幼林生长差异不显著。 相似文献
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The role of agroforestry in industrialized nations: the southern hemisphere perspective with special emphasis on Australia and New Zealand 总被引：2，自引：0，他引：2
D. J. Mead 《Agroforestry Systems》1995,31(2):143-156
Agroforestry in Australia and New Zealand is dominated by silvopastoralism. Farmers may employ combinations of shelterbelts, shade trees, widely spaced trees over pasture, or more densely planted woodlots. In addition to wood production and shelter, erosion control, amenity and landscape planting, and conservation of natural forest are often important. Many farm forestry people show considerable innovation.In temperate wetter areas of Australia, eucalyptus and, to a lesser extent,Pinus radiata (radiata pine) dominate agroforestry tree plantings for wood, shade, shelter, and salinisation and erosion prevention. The One Billion Tree Program, initiated by the Australian Federal Government, provides limited funding for tree planting. Joint farmer ventures with the State or local industry are also common. Most State governments also provide advice, and planting is tax deductible. Local landcare groups, formed to encourage sustainable agriculture, often promote tree planting, particularly where soil degradation is a problem. Melbourne University and other Techncial Institutes offer training in agroforestry.In New Zealand, a third of the farms require trees for soil conservation. This, together with the growing recognition of the financial benefits of planting trees, has resulted in small landowners doing most of the current planting of 80,000 to 100,000 ha yr–1. Most farmers plant radiata pine, but eucalyptus and other hardwoods, including willows and poplars, are also widely used. There are almost no government incentives for tree planting in New Zealand. The Farm Forestry Association is the major extension organization. Lincoln University has an important teaching and research commitment, and the New Zealand Forest Research Institute Limited has developed very useful management models. 相似文献