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在对湖南省永顺县现有古树资源及其特征调查的基础上进行了综合分析和评价,结论是:现保存有古树共3408株,其中三级古树3052株,占89.6%;二级古树286株,占8.4%;一级古树70株,占2.1%;现有古树分属38科、70属、106种,其中国家级保护珍稀树种15科、18属、20种。古树中珍稀保护树种现生长较好的有黄心夜合(珍稀树种)古树32株,其中有树龄超过1000年的古树3株;珙桐古树(Ⅰ级保护植物)42株,其中有树龄在500年以上的古树1株;青钱柳古树(省级保护植物)7株,大叶榉古树(Ⅱ级保护植物)7株,青檀古树(Ⅲ级保护植物)6株;黄杉(国家Ⅱ级保护树种)古树群落2处,共有古树426株。古树资源分布广泛,且多为零星分布,少量以小片状或群落形式分布;古树主要分布在海拔300—600m的地段,其中大部分生长良好;古树资源开发利用潜力大,但保护现状不容乐观。 相似文献
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分析了丽水地区林区国有森工企业经营现状,揭示了当前面临的主要挑战--可伐资源减少、市场竞争激烈、企业负担沉重、经济危困、严重缺乏经营与管理人才,提出了今后的发展方向与对策;(1)适应形势,实现战略转移;(2)深化改革,搞活机制;(3)创造条件,积极培育市场:(4)培育资源,扩大基地建设;(5)狠抓教育,提高职工素质;(6)用好政策,争取加强领导。 相似文献
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基于2019年12月南涧凤凰山候鸟州级自然保护区综合考察结果的基础上通过野外实地调查、访问调查、植物标本采集和整理分类,初步查明了保护区范围内的植物资源种类,分析了野生种子植物资源和区系,结果表明:(1)保护区共记录维管束植物113科313属451种,其中人工栽培植物有11科29属38种,野生植物有102科284属413种;(2)保护区内共有12个群落组成;(3)保护区内以菊科、禾本科、蔷薇科、蝶形花科、唇形科、蓼科植物为主;(4)保护区的植物在科级水平热带分布较温带分布更具紧密性;属级水平与北温带分布及其变型有紧密联系,说明保护区在植物区系上具有典型的温带特征;从种级水平来看,保护区分布着数量众多的中国特有植物;(5)保护区内资源植物比较多,为了更好地保护和合理利用资源植物,对于经济价值较高,原料需求量大的种类,应积极进行引种栽培。 相似文献
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影响桉树插穗生根的几个因素研究 总被引:5,自引:0,他引:5
通过6年的桉树扦插育苗研究,总结出影响插穗生根有6个因素:(1)母株来源,组培苗作母株的插穗比扦插苗作母株的生根状况好;(2)母株年龄,母株在1-3年生时采穗条扦插生根率高;(3)穗龄,桉树穗条上长有3-4对成熟叶时扦插成活率高;(4)穗条留叶面积,在扦插不良季节,桉树扦穗留叶至1/3面积的生根率最高,而地扦插良好季节,桉树插穗留叶至2/3面积生根率最高;(5)扦插季节,桉树扦插最佳季节为每年的11月份至次年的4月份;(6)植物生长调节剂,吲哚丁酸(IBA)作生根激素使用效果比萘乙酸(NAA)好。 相似文献
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我国水土流失危害及防御对策 总被引:2,自引:2,他引:2
分析了我国水土流失对国民经济造成的危害,因地制宜地提出了防治水土流失的对策;(1)良化生态环境;(2)坚持土地的综合治理;(3)坚持小流域治理;(4)提高江河湖海的防洪能力;(5)加大水土保持的执法力度;(6)增强保水保土意识。 相似文献
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蜂窝板托盘的技术条件及生产工艺 总被引:2,自引:0,他引:2
我国木材资源短缺,如何用其他环保再生材料代替木材包装材料已成为一个亟待解决的新课题.蜂窝板正是一种新型的以纸代木的环保材料,具有质轻、抗压、抗震性能好、可循环使用等优点.本文分析国内外代木包装的现状,阐述蜂窝板托盘的结构和物理性能,论证其制造托盘的可行性以及蜂窝板托盘的生产工艺,并就生产中的相关问题提出合理化建议. 相似文献
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《Wood material science & engineering》2013,8(4):217-224
Abstract Considering ongoing global deforestation and the increased demand for raw materials in all wood-processing sectors it is necessary to seek and employ alternative resources. Agricultural residues are potential sources of alternative lignocellulose-based raw materials. Research on substitute materials for wood panel production mainly focused on physical and mechanical properties of boards while much remains to be learned about machining. Therefore, studies were carried out to analyse the relationship between ash and silica content and their impact on tool wear. Ash and silica contents of agricultural residues were determined following ISO 3340. Particle morphology and elemental composition of selected materials were analysed using scanning electron microscopy and energy-dispersive X-ray analysis. Tool wear tests were carried out using particleboards made from wheat straw, canola straw and spruce. Analyses of various plant materials displayed no correlation between ash and silica content. Bio-mineralised silica structures in wheat and canola were different compared to coarse silica found in wood-based particleboard. Tool wear caused by these agricultural residues was just moderately increased compared to wood, despite the fact that their silica contents were many times higher. Furthermore, the impact of abrasive substances on wear behaviour was influenced by the density of the panels. 相似文献
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高性能重组竹制造技术研究 总被引:3,自引:1,他引:2
基于丛生中小径级竹材资源丰富,工业化利用水平低的现状,开发了以竹代木的高性能重组竹新材料。高性能重组竹可代替木材、节约木材资源,形成新型资源产业链;同时,解决三农问题,推进社会、生态、经济的平衡发展。 相似文献
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福建鸳鸯猕猴自然保护区经济植物资源调查 总被引:2,自引:0,他引:2
福建鸳鸯猕猴自然保护区有野生经济植物108科503种,按其用途划分为15类.该区野生植物资源种类丰富、用途广、分布面积大、替代种类较多,且该区具有优越的野生植物再生条件,十分有利于野生植物资源的开发和利用. 相似文献
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《中国林业科技(英文版)》2009,(2)
Bamboo and Rattan(B&R) resources play a very important role for ecological and economical development as the two most important non-timber forest resources,due to deterioration of global ecological environment and supply pressure of timber resource.B&R industry has always been regarded as one of the green industries with great development potential as B&R can be used as wood substitute. Many countries and regions have their distinct advantages and successful experiences in developing bamboo and rattan in... 相似文献
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发展竹浆造纸 节约木材资源 总被引:4,自引:0,他引:4
随着社会经济水平的发展,中国纸及纸板的现有产品结构已不适应纸张消费市场的变化与发展,加剧了国内市场对进口纸及纸板的依赖性。竹材纤维细长,是制浆造纸的优质原料。竹浆纸的开发有利于节约木材资源,有利于环境保护。中国竹资源丰富,发展竹浆造纸的市场前景非常广阔。因此,在造纸工业中实现以竹代木,建立林纸一体化的竹浆生产基地,将成为节约木材资源,减少纸及纸浆的进口,使制浆造纸工业得以持续发展的有利途径。 相似文献
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我国木梳素以小叶黄杨、楠木、枣木、梨木等树种为制梳材料。由于人口膨胀,木梳需求量巨增,制梳原材料渐已匮乏,绵延1 500多年的传统木梳手工艺文化正面临消亡的威胁。笔者选择速生树种——意杨为制梳材料,按木梳实用功能和产业经济的实际需求,对意杨压缩木进行一般物理特性试验,对其木梳制品进行实用和成本分析,最终确定50%左右的意杨压缩木完全能替代木梳传统原材料。 相似文献
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城市木材工业是城市林业的组成部分。在发展城市林业的木材工业生产时,要遵守森林资源的综合利用与环境保护相协调,要特森林资源节约放在首位。因此,在发展城市木材工业生产过程中,推行减量化、回收利用、再循环、重组合、代用品、重现性、重整修、再生产等一系列措施,使城市木材工业稳步地可持续发展。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(3):272-280
Abstract Biomass has become a popular alternative to satisfy expanding energy demand and as a substitute for fossil fuels and phased-out nuclear energy in Europe. The European Union White Paper stipulates that the utilization of biomass shall increase to 1566 TWh by 2010. However it is often overlooked that the forest resources are already, to a large extent, used by the forest industries. When promoting biomass for energy generation the consequences for the forest industries also need to be considered. Sweden is an excellent case study, as there are vast quantities of forest resources, nuclear power is starting to be phased out, there are restrictions on expanding hydropower and the political desire exists to “set an example” with respect to carbon dioxide emissions. This paper attempts to estimate and analyse the supply of two types of forest resource, namely, roundwood and harvesting residues derived from final harvesting and commercial thinnings. Two separate supply curves are estimated: one for roundwood and one for harvesting residues. The cost structure is based on an economic-engineering approach where the separate cost components are constructed from the lowest cost element into aggregates for labour, capital, materials and overhead costs for each forest resource. The results indicate an unutilized economic supply of 12 TWh of harvesting residues in Sweden. However, after these 12 TWh have been recovered it becomes more profitable to use roundwood for energy purposes than to continue extracting further amounts of harvesting residues. 相似文献