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1.
城市绿化树种的选择,应考虑以下几方面: 1.因地制宜,因树制宜,适地适树。以乡土树种为主,适当推广多年来适应本地自然条件的外来树种,引进适应本地自然条件的优良树种。引进树种要事先进行引种试验,避免不必要的损失。  相似文献   

2.
阐述了城市绿化树种引种驯化的一般要求 ;总结了目前吉林市绿化树种应用及引种驯化情况 ;对引种驯化技术作了介绍 ;指出在积极引进外来树种的同时 ,也要挖掘本地优良特色品种 ,以使城市绿化树种更加丰实  相似文献   

3.
通过对樟子松不同种源试验林高生长和径生长的调查得知,地理种源不同,高生长存在着显著差异,一般人工林种源生长好于天然林种源。樟子松经过几十年的引种驯化是能够适应当地的环境条件,形成稳定种群。造林时,首先应选择种子产地土壤、气候条件与本地相似的地区调拨种子。若本地自然条件与种子产地相差较大,应选择经过长期引种已形成稳定种群的种子产地调拨种子,如9007(净月潭)、9014(章古台)、9006(高峰)、9012(青山)号产地的种子。  相似文献   

4.
(一)林木引种及其意义林木引种,就是引进外来树种。外来树种是指本地不能自发分布,而在外地(包括外国)有自然分布的树种。引种成功的标志是:引进的外来树种与原产地比较,不需要特殊的保护而能越冬过夏良好地生长,没有降低原来的经济性状,能正常地开花结实和自然地繁殖自己。保证林木引种成功,不外乎选择适生的树种或给予适合生长的环境条件,或者利用有性杂交以改变其遗传性使之适应新的环境条件。现在世界上公认的引种原则是,要求原产地和引种地区生态条件相似,但不要  相似文献   

5.
乡土树种在园林绿化中的开发利用   总被引:2,自引:0,他引:2  
所谓乡土树种,是指本地区天然分布树种或者已引种多年且在当地一直表现良好的外来树种。以扎兰屯地区为例,植物种类共有96科334属709种。随着园林绿化的迅速发展,乡土树种的开发利用也在逐步引起重视。本文根据有关文献资料,结合现状,对乡土树种在园林绿化中的开发利用作些粗浅  相似文献   

6.
乡土树种适应性广、抗逆性强、不易感染病虫害、易于养护管理、能自然繁衍成林.我们通常把当地土生土长的、经过长期种植,能很好地适应当地土壤、气候等自然条件,自然分布、自然演替,已经融人当地的自然生态系统中的树种,统称为乡土树种.有些树种尽管不是当地土生土长的原产树种,是外来树种经长期驯化栽培后的归化树种,但它们已经具备了乡...  相似文献   

7.
国外生态经济树种沙棘引种驯化及早期评价   总被引:1,自引:0,他引:1  
为丰富我国高寒地区生态经济林树种遗传多样性,促进林业生态体系和产业体系建设,遵循供种区与引种区环境条件相似的原则,根据引种区气候、土壤、植被分布、地形地貌及地理位置等主要环境条件,确定与之相适宜俄罗斯为供种区。以6个俄罗斯大果沙棘优良品种为引种对象,在引种驯化及区域试验的基础上,综合分析与评价子代生态适应性、生长表现及果实品质,确定YSH和HJN为高寒地区引种栽培的适宜品种,且品种内家系间数量性状变异较小,生长稳定,具广泛推广应用价值。  相似文献   

8.
树木引种,一是变外地分布为本地生长,引进国内外优良树种,以丰富本地的造林树种;二是变野生为家生,充分合理地利用当地的自然条件,挖掘本地的树种资源。引种是实现林木速生、优质、丰产、经济有效的途径。郎溪县引种的国外松,主要为原产美国东南部、海拔200~500m的火炬松和原产美国东南  相似文献   

9.
本文介绍了福建省林木种质资源的收集保存、研究利用,优良家系选育,树种内种源研究,高世代种子园研究,乡土树种栽培驯化,外来树种引种,提高种子园种子产量所采取的措施,无性繁殖技术等林木良种繁育概况;并就林木育种工作存在的问题及今后工作设想提出建设性意见。  相似文献   

10.
榆林沙区自然环境恶劣,植被稀少。因此在生态环境建设中不仅要应用乡土树种,还要引进外来优良树种,以丰富榆林市的树木资源,使绿化达到更完美的效果。而如何将乡土树种与外来树种协调应用是关键所在。只有在保护好乡土树种资源的同时,有原则、有目标、有步骤地进行引种,使之不发生生物入侵,才是正确的培育措施。  相似文献   

11.
通过对福建省乡土野生绿化树种调查,筛选出园林观赏价值高、经济效益好的福建山樱花、香港四照花等10种乡土野生绿化树种进行驯化栽培试验,总结出栽培配套技术和3年生各树种生长情况,投入产出比达1∶3~1∶13,获得显著社会、生态和经济效益,为园林规划和林业生产提供科学依据。  相似文献   

12.
对东莞大岭山村边自然次生林(俗称“风水林”)调查表明,群落组成种类复杂并富于热带性,1hm^2样地内共有维管束植物111种,隶属56科89属,其中以木本植物占绝对优势,有67种,占60.36%;群落中种子植物属为热带分布的共有74属,占总属数的92.5%。群落乔木可分三层,以越南山龙眼为主,其在各层的重要值分别为117.12%,129.44%和57.41%;灌木层以罗伞树和九节等为主;草本层植物以乔灌木小苗为主,草本植物仅沿阶草、海芋和半边旗等少数种类。群落木本植物的科、属、种对区域物种库的贡献率较大,分别为37.7%,25.6%和22.5%,以藤本植物的贡献率最高,接近50%,乔灌植物的贡献率也在20%左右.与鼎湖山季风常绿阔叶林比较.两者物种组成结构相似.但组成种娄仍有一定差距.  相似文献   

13.
Many boreal tree stands are neither clearly even-aged nor clearly uneven-aged. The stands may undergo a series of stages, during which an even-aged stand is transformed into two-storied mixed stand, and finally to multistoried or uneven-aged stand structure. The species composition often changes during the succession of stand stages. This study developed models for stand dynamics that can be used in different stand structures and species compositions. The model set consists of species-specific individual-tree diameter increment and survival models, and models for ingrowth. Separate models were developed for Scots pine, Norway spruce, and hardwood species. The models were used in a growth simulator, to give illustrative examples on species influences and stand dynamics. Methods to simulate residual variation around diameter increment and ingrowth models are also presented. The results suggest that mixed stands are more productive than one-species stands. Spruce in particular benefits from an admixture of other species. Mixed species improve diameter increment, decrease mortality, and increase ingrowth. Pine is a more beneficial admixture than birch. Simulations showed that uneven-aged management of spruce forests is sustainable and productive, and even-aged conifer stands growing on medium sites can be converted into uneven-aged mixed stands by a series of strong high thinnings.  相似文献   

14.
从植物多样性恢复利用的角度来探讨治理流动沙地的有效途径和方法,对正蓝旗科技支撑示范区的人工模拟飞播植物群落进行了调查和分析,结果表明:项目实施区中的扁蓿豆、冷蒿、冰草等10种植物的重要值均大于对照区;二裂委陵菜、苔草、虫实等10种植物重要值均小于对照区;物种丰富度指数大于对照样地,Alatalo均匀度指数小于对照样地,而多样性指数明显大于对照样地;1年生草本植物种的重要值低于对照区,而多年生草本植物明显高于对照区。  相似文献   

15.
植物引种与外来物种入侵的探讨   总被引:7,自引:0,他引:7  
孙莉 《森林工程》2004,20(6):6-8
生物入侵正在成为影响我国生态系统的重要因素之一。外来生物入侵的问题 ,越来越受到全社会的关注。本文主要分析了我国外来入侵植物的现状 ,如外来入侵植物的主要种类、对我国生态环境的危害、主要传入途径以及监控措施。  相似文献   

16.
北京地区主要树种理化性质研究及易燃性初步分析   总被引:5,自引:1,他引:4  
森林燃烧所释放的热量、火种类、火行为等各种林火属性与树种易燃性密切相关,而树种的理化性质在一定程度上制约着易燃性,因此对树种理化性质和易燃性的研究是必要的。基于20种树种的实验分析,确定了可燃物热值、抽提物含量、灰分含量、含水量、密度的相关性,并建立相应的回归模型;基于树种理化性质的分析,比较了20种树种的易燃性,进行排序并划分等级。  相似文献   

17.
Reforestation, particularly in the tropics, is of crucial importance for the environment as well as society. However, small planting areas and low participation of smallholder farmers in tree planting programmes often obstruct realisation of set planting area targets. In this regard, we interviewed smallholder farmers undertaking indigenous species reforestation in Oda Kotoamso community within the Wassa Amenfi West District in Western Region of Ghana with a pre-tested questionnaire to identify (1) key socio-economic factors that predict the size of plantations they establish, (2) options that could encourage tree planting among smallholder farmers, and (3) tree species planted by the smallholder farmers and their conservation status according to the IUCN Red List of Threatened Species. Key socio-economic factors were predicted with multiple regression models and ANOVA. Options were ranked on a five-point Likert scale and their differences were tested with the Mann–Whitney U test. Age and income of smallholders are the significant predictors of plantation sizes but farmers’ household size and gender were not significant. Age and income accounted for 77.1% and 22.9%, respectively, of the total variation described by our model (R?2 = 38.4%). In order of importance, incentives (mean = 4.35, SD = 0.48), public nurseries (mean = 4.2, SD = 0.82) and agroforestry (mean = 4.06, SD = 0.56) were the options that could encourage reforestation, though incentives and public nurseries were not significantly different (p > 0.05). Almost half (9 of 19) of the tree species planted are categorised as Vulnerable species, which highlights the contribution of smallholder farmers to recovery of threatened tree species. Our findings suggest that sustainable provision of planting materials in incentivised and youth-based tree planting programmes could increase planting hectarage and conserve threatened tree species.  相似文献   

18.
在对重庆市的自然条件及社会经济状况分析的基础上,对实地调查和通过资料查阅确定的60种重庆市优良乡土树种进行了综合评价及选择。分别依据不同用途的树种制定不同的选择标准,确定出若干评价指标:对用材树种选定了速生性、丰产性、耐瘠性、抗寒性、抗旱性、抗病虫害能力、干材形质、材用价值等8个指标;对生物质能源树种选定了速生性、丰产性、耐瘠性、抗寒性、抗旱性、抗病虫害能力、多用途性、工业价值等8个指标;对景观树种选定了观叶、观花、观果、观树形、抗寒性、抗旱性、抗病虫害能力、抗污染性、吸硫能力、滞尘能力、降低噪音能力等11个指标。采用3分制并提出了每个指标的分级标准,运用层次分析法来确定各个指标的权重,根据各指标的分值和权重对60个目标树种进行了综合评价。主要结果与结论如下:(1)对20种用材树种进行综合评价的结果表明:鹅掌楸、香椿、桤木、檫木、毛桂、香樟为综合效益较高的用材树种,苦楝、川楝、厚朴、山杜英等树种次之。(2)按照20种生物质能源树种的综合评价值大小,建议选择杜仲、桤木、苦楝、刺槐、光皮树、山桐子等树种作为生物质能源林建设的主要树种。此外,灯台树、山苍子、文冠果、麻栎、栓皮栎等可以作为备选树种。(3)通过对20种景观树种的综合评价分析得出,深山含笑、四照花、珙桐、栾树、枫香、厚朴等是非常优异的观赏树种,可作为绿化骨干树种,枫杨、山桐子、红豆树、伯乐树等可作为绿化基调树种。  相似文献   

19.
Abstract

Conservation organizations in the Condor Bioreserve (CBR) in northern Ecuador use the spectacled bear (Tremarctos ornatus) as a surrogate species to focus conservation efforts. However, the utility of single-species management has been questioned in recent scientific literature, making it appropriate to review the spectacled bear's efficacy as a conservation tool. The spectacled bear does not enjoy unqualified public support in CBR and surroundings, suggesting that it may not be appropriate as a flagship species. It may be more effective as a keystone species; its diet and migratory habits suggest that it may have a significant impact on plant community structure through fruit dispersal. However, more research is needed in this arena before drawing any conclusions. The spectacled bear is perhaps most appropriate as an umbrella species because of its large home range, which encompasses at least two ecosystem types: páramo and montane forest. Traditionally, the concept of the umbrella species has stressed minimum area requirements, but the spectacled bear may be a more effective umbrella species if its dispersal requirements and seasonal migration patterns are also addressed. Eco-Ciencia, an Ecuadorian research organization, recently constructed a habitat model for spectacled bear. They are uniquely positioned to address issues of habitat connectivity both within and between the protected areas of CBR. In doing so, they could influence future zoning decisions in and around CBR, an area that is experiencing rapid population growth. This could improve conservation efforts for spectacled bear and other species.  相似文献   

20.
以围场县木兰林管局3种典型森林植被类型为研究对象,从乔木层、灌木层和草本层分别对其物种数和多样性进行了比较。结果表明:落叶松桦木混交林内植物种类有56种,山杨桦木混交林内有53种,油松蒙古栎混交林有44种,乔木层物种多样性差别不明显,灌木层生物多样性指数总体上油松蒙古栎混交林>山杨桦木混交林>落叶松桦木混交林。草本层生物多样性指数除Simpson指数外,其他3个指数规律一致,即油松蒙古栎混交林>山杨桦木混交林>落叶松桦木混交林。  相似文献   

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