共查询到20条相似文献,搜索用时 187 毫秒
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我国南方气候条件好,土地生产能力高,非常适合珍贵树种的生长,加上市场经济发展较快,珍贵树种的供求矛盾突出,成为珍贵树种发展较快的地方。据调查了解,广东、福建、浙江等省为发展珍贵树种较早和较好的地区。 相似文献
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广东、福建发展珍贵树种理念新,思路广,通过示范引导、科技带动和政策扶持,初见成效。山西省珍贵树种发展尚处于起步阶段,通过考察学习两省发展珍贵树种的主要做法,提出山西省发展珍贵树种必须提高认识、科学规划,做到科技先行、示范带动,并制定优惠政策,增加投入。 相似文献
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珍贵树种是经济社会发展特需的战略资源,发展珍贵树种资源具有十分重要的意义。文章介绍了四川珍贵树种资源发展现状,分析了珍贵树种资源发展潜力,提出了珍贵树种资源发展原则和发展战略。 相似文献
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小陇山林区植物种类繁多,存有多种可提供优质木材或具有重要经济、科学研究、文化、药用、观赏等价值的珍贵树种。通过调查,掌握了小陇山林区主要珍贵树种的分布、生境特点、重要价值、育苗方式、造林苗木苗龄等基础资料;从珍贵树种培育的必要性分析出发,依据多年的生产实践,提出了珍贵树种培育的途径,可为小陇山林区及相似林区珍贵树种发展提供指导。 相似文献
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大果紫檀的育苗栽培技术 总被引:4,自引:0,他引:4
大果紫檀是珍贵的红木类树种,原产东南亚热带地区,引种到云南西双版纳热带植物园生长迅速,心材形成千,并大量结果,是优良的珍贵造林树种.文章对其种子特性、生态习性、育苗及造林技术作了较详细的介绍.建议在云南、海南岛、台湾、广东、广西、福建等省区条件适宜地区进行试种并发展造林. 相似文献
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简述广西珍贵树种发展现状,分析广西珍贵树种发展潜力,并提出该地区发展珍贵树种中应注意的问题,旨在为珍贵树种在广西大力推广提供理论参考。 相似文献
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介绍了安化县近些年来珍贵树种资源现状及取得的成效,并从加强领导、政策配套、科技支撑、价值宣传、创新机制、优惠扶持等方面总结了安化县珍贵培育工作取得的经验,最后针对安化县珍贵树种发展过程中存在的一些问题提出相应建议。 相似文献
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Mathias Hofmann Tina Gerstenberg Sten Gillner 《European Journal of Forest Research》2017,136(3):421-432
This paper presents a psychological perspective to the selection of trees for urban residential areas. Sixty tree species suitable for urban planting sites were rated by lay participants regarding preference. We then used outward tree features to predict the preference ratings. Twenty-five different plant characteristics served as possible predictors in a regression model for tree preference. We found that the distinction between conifers and deciduous trees, the maximum tree height, and the crown height-to-width ratio were valuable predictors for preference, explaining more than 70% of the variance. This adds support for evolutionary theories of landscape preference. The regression model presented in this paper can be applied to calculate a preference estimate for other tree species using their known physical data, which may facilitate tree selection tasks in green space planning. By specifying preference-relevant tree characteristics, our findings may also inform the process of selecting diverse species for sites where a homogenous overall appearance is a planning goal. 相似文献
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This study explores the diversity in sensitivity to drought of moist tropical forest tree species. Yearly tree growth records collected over a ten-year period in two one-hectare 70-year-old damar agroforest plots in Sumatra are analysed. These agroforests are mixed tree plantations, dominated by Shorea javanica K. & V., a dipterocarp tree cultivated and tapped for its commercially valuable resin (damar). Many indigenous fruit tree species grow in these agroforests, as well as timber tree species originating from the nearby natural forest. During the census period the multi-species stands were subjected to three El Nino Southern Oscillation (ENSO)-related droughts (1994, 1997 and 2002). At the tree community level, these droughts were associated with a marked decrease in radial stem growth. Multilevel modelling was used to explore the relative contribution of species, tree size and individual tree characteristics to the observed response to drought.All tree species appeared to be sensitive to drought but the amplitude of the response varied significantly across species. Predicted species mean decrease in stem radial growth rate on drought years (i.e. years with 6 months with less than 50 mm/month rainfall) ranged from less than 5% to more than 80%. Shared species were ranked consistently between plots indicating that the results were robust. Stem diameter significantly affected tree sensitivity to drought in two species only, but in opposite ways: in S. javanica, larger trees appeared to be less sensitive while the opposite was true for Lansium domesticum, an abundant fruit tree. Individual tree sensitivity to drought contributed significantly albeit to a small extent to the overall response to drought. This individual tree effect did not show any pattern of spatial correlation and hence could not be related to topographic features. It is likely to reflect the individual's unique history and genotype. 相似文献
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应用修复生态学理论和植被演替理论,根据保护区现状和植被修复经验,结合恢复原森林生态系统结构、提高林分抗逆性等植被修复目标,提出了重度受害区植被修复模式、中度受害区植被修复模式、重要经济价值树种营建模式、珍贵树种扩繁模式、防火通道景观配置模式等5种植被修复技术模式。以及各修复模式的树种选择,混交、整地、配置方式及株行距等。 相似文献
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中国的红木树种及其可持续发展对策研究 总被引:14,自引:2,他引:14
红木为世界名贵的木材,因过度采伐,资源已濒临枯竭。因此必须重视红木树种资源的保护与培育。文中介绍了我国的乡土和引进红木树种的种类、分布、生长特性、木材性质与加工利用等方面的情况,针对我国红木树种发展中存在的主要问题,在树种资源保护、发掘与引进以及珍贵用材林基地的营建技术与政策支持等方面提出了发展建议。 相似文献
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通过对陕西天然林几个主要树种根径与胸径的回归分析,回归模型的建立及相关关系进行显著性检验。结果表明,根径与胸径间存在着密切、显著的直线回归关系,根径与胸径间存在着确定的函数关系,所建立的回归模型是成立的、可用的,从而为以根径推算胸径,计算出某一树种单株材积提供了一个方便可行的方法,在营林实践中很有使用价值。 相似文献