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1.
《Southern Forests》2013,75(3):247-253
Genetic materials interact with the environment in specific ways, therefore their responses in wood need to be better understood. The present study sought to evaluate the influence of different climatic conditions in Minas Gerais, Brazil on Eucalyptus grandis × Eucalyptus urophylla wood. Two six-year-old clones were cultivated in Belo Oriente, Ferros, Santa Bárbara, Itabira and Peçanha. Five trees from each clone were sampled from the base to top direction. Wood density, heartwood/sapwood ratio, vessels, fibres, and extractive and lignin contents were determined, as well as their correlation with environmental variables. Vessel diameters, heartwood/sapwood ratio, and extractive and lignin contents all increased due to higher water availability in Santa Bárbara and Itabira. In both genetic materials, the variables linked to growth and wood quality were related to environmental factors.  相似文献   

2.
李敏 《沙棘》2004,17(4):17-22
沙棘通过为其他物种提供养分和栖息地,链接了生态链上的其他(树草、禽兽、虫菌等)物种,使种植区域内消失的物种得以重现和发展,在半干旱生态系统中的一定条件下,扮演了关键种的角色,发挥了关键环节的作用,实现了生物多样性保护。除非在极端条件下,沙棘一般不会形成顶级群落(纯林),而只形成“过渡性群落”,为植被演替提供条件。发展沙棘促进了农业发展,增加了农民收入,在更大范围、更深层次、更广概念的生物多样性保护方面发挥了积极的作用。发展沙棘与推广其他树种(柠条、杨、柳)在生物多样性保护上存在显著的优势,沙棘在半干旱地区生物多样性保护中发挥了极其重要的作用,今后应当在大力推广的同时,注重改良品种,营造混交林,继续研究如何提高种植区农民对沙棘的利用效益。  相似文献   

3.
锰在植物体内生理功能研究进展   总被引:32,自引:0,他引:32  
从锰胁迫对植物的影响、锰在植物的光合作用、氟化还原和多种酶活化中的作用及锰与其它元素的关系等方面综述了锰在植物体内的主要生理功能,为植物锰营养研究提供研究资料。  相似文献   

4.
由于世界性科学技术的飞速发展与我国改革开放的巨大推动,古老的农业正由传统的经验型逐步进入了现代化科学生产阶段。作为农业生产重要组分的果树生产同样出现了许多重大的技术变革,给我国果树生产注入了新的活力。这些变革主要包括品种、育苗、改土、施肥、浇水、改制、修剪、植保、管理、流通等十个方面。  相似文献   

5.
东北地区公路边坡生态防护植物的选择   总被引:2,自引:0,他引:2  
根据东北公路边坡的气候特点和土壤条件,对公路边坡生态防护用植物选择进行了探讨,提出了适用于东北地区公路边坡的草本植物、灌木树种和藤本植物,对东北地区公路边坡的生态防护具有重要的现实指导意义。  相似文献   

6.
位于都市城近郊村镇的园林苗圃经过多年高速发展,普遍面临转型升级。发掘苗圃作为城市绿地系统的生态景观功能,从中寻找激发苗木企业活力的机会不失为一条可行途径。本文以地处北京顺义区近郊的苗圃为例,以提升苗圃景观价值、发挥游憩功能为导向,吸纳农村劳动力,通过重新规划,体现生态理念,注重园林形态美、色彩美、意境美的营造,旨在为都市观光型苗圃建设提供参考。  相似文献   

7.
我国松树寄生线虫名录   总被引:1,自引:0,他引:1  
目前我国松树寄生线虫有40个已知种和一些未定种,这些种分属于3目9科17属,该文从线虫分布和寄主两个方面列出名录.  相似文献   

8.
无人机在我国林业上应用概述   总被引:1,自引:0,他引:1  
文章对无人机在我国林业上的应用做一归类,主要包括在森林资源调查、森林资源监测、森林信息提取等方面的应用,并提出无人机在我国林业上应用存在的问题及建议。  相似文献   

9.
通过本地区农业生产的特点,论述了农业机械化技术推广在农业生产中的作用。  相似文献   

10.
针对山岭地区道路测量条件艰苦、工作量大的实际问题 ,本文研究了用数码相机在现场进行两点或多点拍照 ,然后在室内用照片中已知 4个点的位置坐标求得任意点的地理位置 ,解决了道路设计中地形情报采集难的问题 ,有效地提高测量效率  相似文献   

11.
随着人们安全健康意识提高,食品中农药残留问题更加受到重视,本文综述了样品预处理研究进展及农药残留快速检测技术研究进展,并简单分析介绍各种方法的优缺点。  相似文献   

12.
乌兰察布市兴和县山区春季雨季造林与管理措施的浅析   总被引:1,自引:0,他引:1  
文章针对乌兰察布市兴和县山区利用春季雨季的有利时机,搞好造林,提高造林成活率,春季雨季造林技术及管理粗浅的想法。  相似文献   

13.
范钟琪 《广东园林》2021,43(6):13-16
寺庙园林历史底蕴深厚 , 文化内涵丰富,园内的植物更是其独特内涵的体现。以唐代岭南佛教中心桂林的寺庙园林为例 ,研究其中植物景观的种类特点与配置结构。结果发现:11 处寺庙园林共有园林植物 75 种,隶属 52 科 67 属,其中桑科榕属 Ficus植物和天门冬科植物是最主要的组成部分;并且有些园林植物 ( 如桂花Osmanthus fragrans 、樟Cinnamomum camphora 等)既蕴含佛教内涵又体现了壮族文化。总体而言,桂林寺庙园林植物景观建设不仅体现了独特的山水特征,也包含着壮族文化底蕴。  相似文献   

14.
根据野外调查、标本采集和室内外对比、资料查证,初步统计显示:重庆地区具有森林食品价值与作用的植物资源共计86科187属286种。现列出重庆地区主要森林食品资源名录,为重庆地区森林食品的开发利用提供基础资料。  相似文献   

15.
ABSTRACT

Watersheds have become strategically important for the survival of cities due to the accelerated increase in both the demand and the rapid deterioration of the water intended to supply the urban populations. The present article aims to present the applicability of the “multicriteria method” to help the Government of the State of Sao Paulo, Brazil organize payment for environmental services for watershed protection using the “Delphi method” as the principal methodology. This article consists of a review of the literature and a case study of the Mina d’Água program from the State Secretary of the Environment (within the Government of São Paulo) in partnership with other municipalities (city by river basin). The article also covers the advent of pertinent climate change laws. The positive results in the use of the Delphi method represent a fruitful tool to facilitate communication between groups of experts and the public, encouraging better judgment and a more consistent decision-making process.  相似文献   

16.
文章记述了内蒙古大兴安岭林区鳞翅目粉蝶科已知19种,包括斑缘豆粉蝶Colias erate Esper、北黎豆粉蝶Colias viluiensis Men、黑缘豆粉蝶Colias palaeno Linnaeus、黎明豆粉蝶Colias aurora Esp、北方豆粉蝶Colias melinos Ev、兴安豆粉蝶Colias tychede Boeber、橙黄豆粉蝶Colias fieldii Menetries、镏金豆粉蝶Colias chrysoheme Esper、绢粉蝶Aporia crataegiL、菜粉蝶Pieris rapaeL、东方菜粉蝶Pieris canidia Sparrman、暗脉粉蝶Pieris napiL、黑纹粉蝶Pieris melete Menetries、云粉蝶Pontia daplidiceL、绿云粉蝶Pontia chloridice Hubner、钩粉蝶Gonepteryx rhamniL、尖钩粉蝶Gonepteryx aspsiaMen、莫氏小粉蝶Leptidea morsei Fenton和突角小粉蝶Leptidea amurensis Mentries。并对其形态特征、习性、寄主和分布进行了简要介绍。  相似文献   

17.
无锡新农村绿化建设及模式初探   总被引:11,自引:2,他引:9  
文章根据江苏无锡的自然地理条件与城乡一体现代林业建设实际,结合"绿色无锡"行动计划实施和社会主义新农村建设对环境的要求,对无锡地区新农村建设的理念、基本原则和绿化模式进行探讨,并提出村庄绿化有关研究的建议。    相似文献   

18.
Progresses in restoration of post-mining landscape in Africa   总被引:1,自引:0,他引:1  
Mining alters the natural landscape and discharges large volumes of wastes that pose serious pollution hazards to the environment, to human health and to agriculture. As a result, the recent 2 decades have witnessed a global surge in research on post-mining landscape restoration, yielding a suite of techniques including physical, chemical, biological(also known as phytoremediation) and combinations. Despite the long history of mining in Africa, no systematic review has summarized advances in restoration research and practices after mining disturbance. Thus, the aim of this review was to document the state-of-knowledge and identify gaps in restoration of postmining landscape in Africa through literature review. We found that:(1) there has been substantial progress in identifying species suitable for phytoremediation;(2) few studies evaluated the feasibility of organic amendments to promote autochthonous colonization of mine wastelands or growth of planted species; and(3) restoration of limestone quarries in Kenya, sand mining tailings in South Africa,and gold mine wasteland in Ghana are successful cases of large-scale post-mining restoration practices in Africa.However, the pace of post-mining landscape restoration research and practice in Africa is sluggish compared to other parts of the global south. We recommend:(1)mainstreaming the restoration of mine wastelands in national research strategies and increased development planning to make the mining sector ‘‘Green';(2) inventory of the number, area, and current status of abandoned mine lands;(3) expanding the pool of candidate species for phytostabilization;(4) further evaluating the phytostabilization potential of organic amendments, e.g., biochar;(5)assessing the impacts of mining on regional biodiversity.  相似文献   

19.
20.
In light of a recent increase in the aphid populations on young canola (Brassica napus) in autumn in Northwestern Europe, we carried out a survey of their parasitoid species during this season. The study was done in France from 1998 to 2001 using different sampling methods. Results highlighted the presence of two main species of Aphidiinae, Aphidius matricariae and Diaeretiella rapae (and to a lesser extent Aphidius ervi) on Myzus persicae, and of D. rapae on Brevicoryne brassicae. Nine other Aphidiinae species were found occasionally as well as some Aphelinidae parasitoids and hyperparasitoids. There was no difference in parasitoid species pattern between fields in Northern and Southern France. The principal parasitoid species found in the fields were reared in the laboratory to confirm their ability to develop on the canola aphids. Aphidius matricariae and D. rapae were reared successfully on M. persicae, but a low parasitism rate was obtained for A. ervi on this aphid. This study showed that A. matricariae and D. rapae could develop on aphids on canola and that they are present naturally in canola in autumn. However, the parasitism rate is low in autumn, so the options could be the use of these parasitoids in augmentative release biological control programs or in an IPM project on canola fields during this time of the year.  相似文献   

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