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1.
苗圃转让     
今年顺义区苗圃绿化、美化苗木达1120多种、1.12亿株。其中油松、白皮松、华山松、雪松、桧柏、侧柏等常绿树13157亩,1650万株,占育苗总面积的23%;连翘、碧桃、榆叶梅、紫叶李、紫蔽、紫荆、月季、玫瑰、黄刺梅、黄杨、女贞等花灌木5468亩,1455万株,占育苗总面积的10%;白腊、元宝枫、栾树、国槐、银杏、合欢、龙爪槐、杜仲、千头椿、金丝柳、各种品种杨等落叶乔木37375亩,8095万株,占育苗总面积的67%。  相似文献   

2.
大丽花块根繁育和栽培技术   总被引:2,自引:0,他引:2  
大丽花(Dahlia pinnata Cav)菊科,大丽花属,多年生草本,原产墨西哥,又名大丽菊、大理花、天竺牡丹、西番莲、地瓜花,具有植株粗壮、花期长、花朵硕大,品种繁多、花色鲜艳、适应性强等特点。是美化公园,布置庭院、花坛、花境以及切花陈设的较好花卉材料。大丽花为世界名花之一,目前世界约有3万多个品种,我国有500余品种。  相似文献   

3.
木棉(Gossampinus malabarica)又名攀枝花、红棉、英雄树、烽火树,属木棉科木棉属落叶高大乔木.木棉广泛分布在我国四川、云南、贵州、广西、广东,生长在江河沿岸、山地阳坡及村边道路旁,喜光、耐高温,对土壤要求不苛刻.在四川攀枝花地区木棉树于1月-2月份开花,先花后叶,花色艳丽,有红色、金黄、淡黄色等颜色,树形高大伟岸,是优良的园林绿化树种.木棉树现是攀枝花市市花和广州市市树,在园林绿化中常作行道树、庭荫树、景园树、盆景树等.木棉经嫁接后2 a-3 a开花,嫁接苗可作盆景矮化栽培,观赏价值高.本文介绍了木棉的嫁接育苗技术.  相似文献   

4.
To improve multi-environmental trial(MET)analysis,a compound method—which combines factor analytic(FA)model with additive main effect and multiplicative interaction(AMMI)and genotype main effect plus genotype-by-environment interaction(GGE)biplot—was conducted in this study.The diameter at breast height of 36 open-pollinated(OP)families of Pinus taeda at six sites in South China was used as a raw dataset.The best linear unbiased prediction(BLUP)data of all individual trees in each site was obtained by fitting the spatial effects with the FA method from raw data.The raw data and BLUP data were analyzed and compared by using the AMMI and GGE biplot.BLUP results showed that the six sites were heterogeneous and spatial variation could be effectively fitted by spatial analysis with the FA method.AMMI analysis identified that two datasets had highly significant effects on the site,family,and their interactions,while BLUP data had a smaller residual error,but higher variation explaining ability and more credible stability than raw data.GGE biplot results revealed that raw data and BLUP data had different results in mega-environment delineation,test-environment evaluation,and genotype evaluation.In addition,BLUP data results were more reasonable due to the stronger analytical ability of the first two principal components.Our study suggests that the compound method combing the FA method with the AMMI and GGE biplot could improve the analysis result of MET data in Pinus teada as it was more reliable than direct AMMI and GGE biplot analysis on raw data.  相似文献   

5.
Natural spruce-fir mixed stand is one of the main forest types in the world,and also has huge ecological,economic and social benefits.According to the structural characteristics and succession laws of natural spruce-fir forest,it is urgent and significant to develop scientific management measures for natural spruce-fir mixed stand in line with local conditions.The article outlined the characteristics of the distribution and structure, regeneration and succession laws of natural spruce-fir forest,and analyzed the current situation and existing problems of natural spruce-fir forest management.The following recommendations were eventually made:1) In no cutting area,all logging activities should be banned.In a restricted cutting area,the cutting intensity should be generally controlled within 15%of the stock volume before cutting.On the commodity forest management area, the appropriate cutting intensity should be determined according to the volume per hectare,determine and classification management should be implemented in accordance with the characteristics of forest,to ensure the scientific selective cutting.2) Closure for afforestation,planting and repair planting should be adopted on vegetation-intensive land,sparse shrubs covered land and harvesting slash,in order to accelerate natural regeneration.3) The in situ conservation should be conducted in nature reserves and scientific experiment stations of rare and endangered species,such as Abies chensiensis,Picea neoveitchii,Abies vuanbaoshanensis,to reduce human destruction.4) It is supposed to collect seeds in time,establish nursery,actively establish forest, expand artificial population and promote natural regeneration.  相似文献   

6.
蚊子、苍蝇、螳螂、臭虫、蜘蛛、蚂蚁之类害虫,在家庭、工厂、办公室、医院、学校、酒店等地,随处可见,无处不入.这些昆虫不但给人们的生活带来很多烦恼,更重要的是,他们导致疾病传播,从而严重危害人们的身体健康.所以,根除害虫,改变居住环境,早已成为人们关注的问题.  相似文献   

7.
肥胖是一种常见的慢性疾病,它是由于生理化机能的改变而引起的体内脂肪沉积量过多,造成体重增加,导致机体发生一系列病理、生理变化的病症.肥胖症是一种全身性代谢疾病,除引起身体外形的改变外,过多的脂肪可带来物理性的负荷,还是各种疾病的"培养箱".肥胖人群平均寿命明显低于正常体重的人群,同时肥胖症还是心血管疾病、糖尿病、脂肪肝、肿瘤的温床,它是一种营养代谢性疾病.减肥首先必须从能量的摄入入手,减少热能的吸收.  相似文献   

8.
当前现代化的航天、航空、汽车、机械、电子、民用建筑、化工等行业迫切要求具备很高的力学性能及耐热、耐磨、耐化学性能的材料.因此高分子材料发展的一个重要方向就是通过对现有聚合物进行物理和化学改性,使其进一步高性能化、结构化、工程化.北京化工大学研制的聚氯乙烯合金是通过挤出机的力学、化学作用及接枝、复合技术使聚氯乙烯塑料工程化,成为物理性能可与ABS相比拟的新材料.聚氯乙烯合金具有高流动性、高韧性,完全可以代替ABS注塑计算机、电视机、冰箱、照相机、仪表等外壳.聚氯乙烯合金还具有良好的耐寒性,可制作各种规格的异型材,包括门窗、上水管道等.产品市场前景好,具有很强的竞争力,有很好的经济效益和社会效益.  相似文献   

9.
This paper proposes an automatic method of pore combination recognition,which is an important feature to hardwood recognition.After extracting edge from wood microscopic cross-section, based on area histogram of the similar circle regions,the method classifies all regions into two classes with maximum between-class variance,so as to distinguish the pore from other textures,which are similar in shapes but different in sizes.Meanwhile, second objective function about average area of closed regions is used to improve the pore segmentation performance.At last,the method uses adjacency degree of pore set to judge pore combination.The experiments demonstrate that the task of pore segmentation can be completed successfully for all kinds of pore distribution and combination,and also the correct combinations of pores are given.  相似文献   

10.
According to the unification principle of system structure and system function of the Water Resource Conservation Forests,seven factors were selected from stand spatial structure,trees structure and healthy of woods,the multifunction management optimization model target was confirmed by using nonlinearity multi-objective programming approach, and the target function-stand spatial structure homogeneity index was defined to establish spatial optimization models with restraining conditions set up in diversity of stand structure and spatial structure.The spatial structure of available typical stand in the wet land area in southern Donting Lake was optimized by means of selective cutting and reinforcement planting.The results showed that the spatial structure was improved obviously and trees diversity and stand health were not weakened.It’s suggested that the established optimization model can effectively guide multifunction management,stand structure optimization and the steadiness of ecological ecosystem and it is convenient and operable in practice,and it’s very important to protect and recover ecosystem of Water Resource Conservation Forests.  相似文献   

11.
火炬松引种试验及优良家系选择   总被引:3,自引:4,他引:3  
邱文金 《福建林业科技》2005,32(1):38-40,59
对从美国引进的火炬松第1代种子园的25个家系,以湿地松、马尾松为对照在福建省漳平五一国有林场开展引种栽培试验,结果表明:火炬松的生长优于湿地松、马尾松;各家系在树高、胸径和材积等性状上有着显著差异,3个性状的遗传力高,根据性状综合表现选择出6个优良家系。  相似文献   

12.
描述为害橡胶树的小蠹虫如角面长小蠹、小杯长小蠹、锥尾长小蠹、对粒材小蠹、橡胶肩角粉蠹、短鞘长腹筒蠹等的形态特征、生物学特性,提出防治方法。  相似文献   

13.
通过梳理特色小镇的相关概念,从城乡协调发展的视角,分析特色小镇发展现状,发现国内特色小镇存在发展过热、民族传统文化缺失、缺乏生态考量、特色产业趋于同化、基本功能得不到满足等问题,提出在发展方向上坚持产业为先,在景观外貌上坚持文化为魂,在生态上坚持以人为本,在规划设计上坚持多规合一等特色小镇发展策略。  相似文献   

14.
颜琳 《广东园林》2008,30(1):18-19
借助自然气象的变化和植物自身的生物学特性。来创造春、夏、秋、冬四季不同的景观效果是中国传统造园植物造景艺术的一大特色。同时,四时造景也是古典园林体现植物景观特色和大自然无穷魅力的重要造园设计手法。  相似文献   

15.
四翅滨藜的表现性状及其在青海省的发展潜力   总被引:17,自引:5,他引:12  
介绍了准常绿饲料灌木--四翅滨藜(Atriplex canescens)的生态习性与形态特性及其在国内外的引种栽培和推广利用情况,阐述陈秦作为饲料的诸多优良特性和在青海畜牧业中的发展潜力,及其在西北地区农业中的发展方向。  相似文献   

16.
对大理感通别墅景观规划设计方案的构思和特点进行了分析,提出现代别墅景观规划设计应基于场地环境的特征条件,从体验基地自然环境、感悟地域文化、把握功能需求入手,通过空间环境的表达创造区域特色别墅环境的规划设计方法。  相似文献   

17.
珍稀植物格木的研究进展   总被引:4,自引:2,他引:2  
文章介绍了近年来有关格木的研究进展,包括生物学特性、育苗造林技术、群落学特征、濒危机制和保护对策等,为格木进一步的研究提供参考。  相似文献   

18.
地肤的利用价值及开发前景   总被引:1,自引:0,他引:1  
主要介绍地肤的分布、植物学特征、特性、营养保健和药用价值以及饲用等价值。在此基础上,分析了地肤的应用现状和开发前景。  相似文献   

19.
[目的]利用星载激光雷达波形数据对森林类型识别时,受地形、噪声和林层结构等因素影响,针叶林、阔叶林和混交林森林类型识别精度较低,为提高森林类型识别精度,需提取与森林类型相关的波形特征参数.[方法]结合回波仿真原理与林分冠层特征对GLAS回波波形进行理论分析,提出了与森林类型相关的波形特征参数147R-cafit-、K1...  相似文献   

20.
高光谱遥感在植被研究中的应用使定量估算植被的生物化学参数和生物物理参数成为可能.分析了樟树幼林生物化学参数与高光谱特征变量之间的相关关系.结果表明:樟树幼林的大部分生物化学参数(叶绿素a含量、叶绿素b含量、叶绿素总含量、类胡萝卜素含量和总磷含量)与高光谱遥感特征参数(蓝边内最大的一阶微分、绿峰反射率、红边位置、蓝边面积、绿峰反射率和红谷反射率构成的比值与归一化植被指数、红边面积和蓝边面积构成的比值和归一化植被指数)之间的相关系数达到了0.01极显著性检验水平;纤维素、总氮含量与高光谱特征参数的相关系数没有达到显著性检验水平.因此,可以利用相关系数达到了0.01极显著性检验水平的高光谱特征参数建立樟树幼林生物化学参数的高光谱遥感估算模型.  相似文献   

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