造林中乡土树种与桉树替代问题的探讨

对当前大规模种植速生桉、引起主要树种比例迅速变化的认识,从乡土主要树种和作用阐明保护乡土树种的观点,提出在发展速生桉的同时,保护乡土树种的观点和建议。     

关于珍贵乡土用材树种资源培育的思考——以本溪市为例

文章探讨了开展珍贵乡土用材树种培育的战略意义,分析了人们对乡土珍贵用材树种的漠视和培育方面存在的问题,以及辽宁省本溪开展乡土珍贵用材树种资源培育具备的优势条件,提出了定向改培和新造林的技术思路及其方法措施。     

造林中乡土树种与桉树替代问题的探讨

对当前大规模种植速生桉、引起主要树种比例迅速变化的认识,从乡土主要树种和作用阐明保护乡土树种的观点,提出在发展速生桉的同时,保护乡土树种的观点和建议。     

通道县乡土树种保护与开发利用

乡土树种的保护与开发利用对现代林业发展和生态文明建设具有重要意义,对通道县乡土树种保护和开发利用现状进行分析,探讨种质流失和遗传侵蚀严重、开发利用滞后等存在的问题,提出了广泛宣传、科学规划、创新科技、落实政策和完善机制等乡土树种保护和开发利用措施。     

乡土树种在柳州城市园林绿化中的应用

乡土树种在城市园林绿化中具有诸多优势：抗逆性、适应性强，能够通过自身循环形成长期稳定的生态系统，从而有效的抵抗各种自然灾害，发挥生态效益。同时，乡土树种是一个城市的自然特征和个性的代表，彰显和凸出城市文化底蕴。本文通过对乡土树种在柳州市城市园林绿化的应用总结，反思在现代园林绿化中乡土树种未能充分利用的原因。     

珍贵树种的推广与培育技术

南方速生珍贵阔叶树种的培育项目是适应广西自治区生态发展、经济发展共同需要而产生的。本文首先介绍了南方速生珍贵阔叶树种栽培试验的具体情况,在此基础上分析了南方速生珍贵阔叶树种培育的主要技术因素,最后提出促进南方速生珍贵阔叶树种的进一步推广的具体措施。     

论乡土优良树种的保存与发展——以三江侗族自治县为例

适当而有计划地按比例发展三江县优良的阔叶林的乡土树种,注重乡土优良树种的保存与发展,是增加绿色的水库的重要举措,既能改良土壤和起到防火作用,又能充分发挥森林的综合效益。     

我国育出彩叶新树种——金冠白蜡

我国又添一种新的乡土彩叶树种，这种彩叶树种名叫金冠白蜡，它已被国家林业局授权为植物新品种。     

黑龙江省乡土彩叶植物应用现状及筛选评价

对彩叶树种在城市园林绿化中的研究进展、应用状况进行基本概述,了解目前国内彩叶树种在园林绿化中的发展趋势;同时对黑龙江省城市园林绿化中彩叶树种的应用状况进行分析,明确了黑龙江省彩叶树种在品种应用方面的匮乏,进而结合我省乡土树种抗性强、变异小、易存活等特点开发本土彩叶植物资源,结合层次分析方法筛选出具有较高观赏价值的秋叶观...     

木兰科种子如何繁育

木兰科植物属速生阔叶树种。该科树种适应性强，生长迅速，树杆通直，叶形奇特，既是优美的庭园绿化树种，又是优良的用材树种，且有较高的观赏价值，在目前城镇园林绿化中普遍采用。为培育出优质壮苗，必须掌握一定的育苗技术。     

关于海南省珍稀树种的调查报告

海南省为我国热带雨林地之一,物种资源丰富,尤其是珍稀名贵树种资源。长期以来,由于对森林资源的不合理开发利用,以及在造林上重视短周期速生林的发展,导致珍稀名贵树种资源越来越少,有些已面临濒危,更谈不上满足社会需求。为保护发展珍稀名贵树种,丰富社会对珍稀树种产品的需求,建议国家启动珍稀树种基地建设工程,地方政府应将珍稀树种发展列入重要议事日程,探索建立珍稀树种发展的长效机制和发展模式。     

Evaluating the impact of government land use policies on tree canopy coverage

Many cities around the world are experiencing the negative effects associated with not sustaining a sufficient level of tree canopy coverage. Tree canopy provides environmental benefits such as clean water and air, erosion prevention, climate control, and native species habitat and provides economic benefits such as higher housing values and lower energy expenditures. We study local government policies in a large U.S. metropolitan area (the Atlanta Metropolitan Statistical Area) to find which policies perform the best at preserving or increasing urban forests. Empirical analysis reveals that a set of effective tree ordinance clauses, zoning ordinances, and having high quality smart growth projects in the community all help in preserving tree canopy in economically and environmentally meaningful amounts. Other actions, such as simply having a tree ordinance, designating a key management person in charge of tree programs, the presence of a tree board, and multiple communication channels were shown to be ineffective for our data set. Because benefits from tree canopy accrue to the local government's budget, to residents and to business owners, the entire community should gain from the passage of effective policies to preserve their local tree canopy. Estimated economic benefits from preserving tree canopy through an effective set of public policies are in the range of $10–15 million annually in an average county, mostly due to savings on stormwater management.     

基于DEM的森林空间分布研究

在Arcgis及其3D和空间分析扩展模块的支持下,计算并探讨武夷山森林主要树种（杉木、松木、阔叶树）在地形因子（海拔、坡度、坡向）各梯度级的分布比重,采用三雏立体林相透视图表达森林的地形分布特征,并对其分布进行了探讨;结果表明,地带性植被阔叶树由于受人为干扰趋向分布于高海拔、坡度陡的山地;杉木林在长年人工经营的过程中,逐渐占据林分的首要地位且主要分布在500m以下的低山丘陵;松木适生性较广,明显倾向分布于（半）阳坡;人们对森林资源的经营和管理,也对森林的空间分布格局产生较大的影响。     

Contribution of associated trees to long-term species conservation,carbon storage and sustainability: a functional analysis of tree communities in cacao plantations of Central Cameroon

In Central Africa, most cacao is still cultivated in low-input agroforests where cacao associated trees are traditionally valued by farmers. These systems are sustainable on the long run, support biodiversity conservation and carbon storage. Yet, little knowledge exists on the contribution of tree community management to explain such results. In Central Cameroon, we investigated cacao agroforest associated tree community contributions to the long-term (i) maintenance of tree species encountering a conservation issue and (ii) carbon storage. We further simulated the simplification of these systems by checking for the effect of tree density decrease on community functional groups or traits. Finally, we linked farmers’ use of associated trees to their functional features and conservation status. Cacao agroforestry systems were able to combine high levels of species richness with long-term conservation abilities and carbon storage. Simplification emphasized consistent shifts of functional traits/groups that will change the way they function and alter the existing balances between different associated tree uses. Since traditional agroforests are now foreseen as providers of timber/non-timber forest products, our study argues that this paradigm change in such low-input systems - if carried improperly - is likely to impair the provision of the services they currently provide as well as their sustainability.     

哈尔滨市道路绿化结构与健康状况分析

应用实地调查的方法,对哈尔滨市区内的保健路、新阳路、中山路、学府路与和平路特色街道绿化带进行实地调查,分别从林分结构、树种组成、数量比例以及健康程度等方面进行综合分析。结果表明,哈尔滨的道路绿化使用的树种较多,丰富了生物多样性和观赏性,但是常绿树种比例严重偏低;乔木灌木树种比例分配不合理,但总体趋势是朝着均衡的乔灌比例方向发展,单一树种的绿化路段已不常见;绝大部分绿化树种个体的健康状态良好,少量个体的健康程度较差,建议在有条件的情况下进行替换。     

Trees,agroforestry and multifunctional agriculture in Cameroon

Modern agriculture has deprived local communities in the tropics of their natural life-support system—the forest resource and the traditional knowledge about indigenous species—and this has not been replaced by employment opportunities or social services. This project in the west and northwest regions of Cameroon takes an innovative three-step approach to improving the lives of local people by establishing rural resource centres (RRCs) to: (i) Rehabilitate degraded land and promote food security through the use of nitrogen-fixing trees to restore crop yields and then the diversification of the farming system with new crops; (ii) Create income generation opportunities from village tree nurseries and the domestication of indigenous fruits and nuts for local and regional trade. Income is rising annually and currently averages $150, $16,000 and $21,000 per RRC after 2, 5 and 10 years, respectively; (iii) Encourage the processing and marketing of food crops and tree products in order to create employment and entrepreneurial opportunities for community members. Income is currently $2400 per enterprise. The project's philosophy is one of helping smallholder farming communities to help themselves: first to become self-sufficient and economically independent, and then to be a hub for the dissemination of knowledge and skills to neighbouring communities.     

生态经济型林业结构组合与经营研究

本文以生态经济学原理为指导 ,结合当地社会经济状况和生产力水平 ,研究总结生态林业结构组合经营模式 ,即以针阔叶树种混交型、生态经济型的生态经济林业结构模式和林一牧、林一农结合、林———工———商———贸结合的产业网络经营模式及其产生的生态、经济、社会效益 ,分析了上述结构的特征及其经营技术措施。     

松嫩平原湖泊湿地植物群落多样性及其保护研究

松嫩平原湖泊群是我国温带亚湿润地区低平原湖泊群,湖泊面积2750km2,湖泊率6%,是我国湖泊密度最大的地区之一,湖泊类型多样,有高等植物148种,隶属于38科77属;有16种植物群落,分属于挺水植物群落、浮叶植物群落、沉水植物群落、漂浮植物群落四大类;研究了松嫩平原湖泊湿地植物群落多样性现状,提出了生物多样性的保护对策;提出了相关的嫩平原湖泊湿地植物群落多样性保护对策。     

Low-cost housing developments in South Africa miss the opportunities for household level urban greening

Most developing countries of the world are experiencing large-scale migration from rural to urban areas. Many new migrants end up in low-cost or informal areas and slums with attendant environmental concerns. One dimension of improved urban sustainability is the provision of green spaces and trees. Whilst many countries have urban greening programmes for public spaces and streets, few have considered the status and potential contribution of trees from resident's own gardens. This paper reports firstly on the policy environment for urban forestry and greening in South Africa and secondly on the maintenance, use and appreciation of trees on private homesteads of residents of new and older low-income suburbs as well as informal housing areas from three small towns in South Africa. In particular we examine if the most recent centrally planned and built low-income housing schemes (called RDP suburbs in South Africa) have considered and incorporated plans or spaces for urban greenery in peoples’ homesteads. We found that broad environmental and sustainability concerns and statements are common in urban development and housing policies, but specific guidelines for implementation are generally absent. More specifically, urban forestry and tree planting are rarely mentioned in the broader land use and environmental policies other than the national forest act and subsequent regulations, but even there it is relatively superficial. In the study towns the prevalence, density and number of species of trees was lowest in the new RDP suburbs relative to the township and informal areas. Consequently, the contribution of tree products to local livelihoods was also lower in the RDP areas. Yet there were no differences in the level of appreciation of the value and intangible benefits of trees between residents from the three different suburbs. This shows that the failure to plan for and accommodate trees in new low-cost housing developments is missing an opportunity to improve overall urban sustainability and liveability and constraining the potential flows of tangible and intangible benefits to urban residents. Making opportunities for such in older suburbs is challenging because of space limitations and cost implications of retrospective provisions, but incorporation into plans for new low-cost housing development should be possible.