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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.
楸树叶面积与叶形指数的回归分析   总被引:7,自引:0,他引:7  
本实验采用数码相机拍照,利用CAD.图像处理方法得到楸树叶片的面积,并同时测量叶长、叶宽计算出长宽比、长乘宽,通过逐步回归的方法对与叶面积有关的指标进行筛选。用最后得到的最能反映叶面积的指标长乘宽,建立不同叶形的叶片长乘宽与叶面积的一元线形回归预测模型方程,分别是倒心形Y=0.652x+16.041,决定系数R2=0.7221,水滴形Y=0.5058x+112.47,决定系数R2=0.4994,三裂Y=0.3211x+155.98,决定系数R2=0.6006,分析认为可将叶长乘宽作为重要的叶形指数,进行楸树生长等相关研究。  相似文献   

12.
油松针叶面积估计模型及比叶面积的研究   总被引:2,自引:0,他引:2       下载免费PDF全文
叶面积和比叶面积是植物生长过程中的重要参数.本研究基于河北木兰围场实测油松数据,通过winSEEDLE种子和针叶图像分析系统获得油松522个单个针叶的表面积LA、针叶长度L、针叶宽W、针叶周长P,分别建立了以针叶长、针叶宽、针叶周长等形状属性为自变量的叶面积估计模型和以针叶干质量为自变量的叶面积估计模型.用总相对误差、平均相对误差、平均相对误差绝对值、均方根误差、预估精度5个统计量来检验模型的误差和拟合优度,经检验模型LA=-2.761 +0.464 L +6.608W和LA =1.345 +0.501X分别为这两种模型中最好,X为针叶干质量.通过对算术平均法、比估计法、最小二乘法3种方法的比较,得到油松的比叶面积为7.08 m2 ·kg-1.本研究为油松叶面积的估计提供了一个简单可靠的方法.  相似文献   

13.
通过帽儿山林场24块标准地的白桦天然林的有关数据,研究了白桦天然林叶量、叶面积与林分年龄和密度的关系。  相似文献   

14.
银杏枝叶生长规律与两次采叶试验研究   总被引:5,自引:0,他引:5  
本文对栽植后两年的银杏嫁接幼树的枝叶生长规律进行了观察,发现银杏新梢具有春梢和夏梢两种;新梢生长有4种方式;短枝亦分春季展叶生长和夏季展叶生长两种,其中春季展叶生长发生于所有短枝顶芽,而夏季展叶生长一般只发生在顶生短枝顶芽。试验证明,采用全采的方式能有效地刺激所有短枝顶芽全部进行夏季展叶生长;采用两次采收方式能使银杏采叶园的产叶量较传统采收方式(一次采收方式)的产叶量提高1倍。  相似文献   

15.
植物功能性状是目前生态学领域关注的热点问题之一,而比叶面积(Specific Leaf Area,SLA)和叶建成消耗(Leaf Construction Cost,LCC)则是功能性状中研究植物资源收获与支出的首选指标。树冠冠层结构与功能在方向上的不同可导致冠层功能性状空间分布的差异。以东灵山辽东栎为研究对象,分析了不同冠层不同方向部位叶片的功能性状以及影响因素。结果表明:在不同空间上,冠层上部的CC均高于冠层底部的,而SLA则相反;除上部与东向外,各方向叶片的比叶面积均有显著差异;热值则是影响二者的主要因素。冠层CC和SLA的空间异质性研究,对于在冠层水平上揭示植物资源利用具有重要意义。  相似文献   

16.
金叶女贞叶斑病的研究   总被引:8,自引:0,他引:8  
通过制作切片、病组织分离培养及单孢分离、接种试验等,确定引起金叶女贞叶斑病的病原菌为Corynespora sp.。此病在上海始发期为4月下旬,高峰期为7-8月和10月。发病率和株密度在一定程度上呈正比关系。80%大生可湿性粉剂是防治此病较好的药剂。  相似文献   

17.
通过穆棱林业局18块标准地中天然红松林的树干解析数据,本文通过数据分析探索了该地区不同林分条件的天然红松林树叶生物量的变化规律,同时对于叶面积随着树冠深度的变化规律也进行了探索。结果表明:叶生物量和叶面积与林分密度之间的关系不显著,随着树冠深度的增加,叶量也逐渐增加。  相似文献   

18.
卢芹  刘晓东  周丹  刘玮 《林业科技》2008,33(3):51-53
以欧洲花楸复叶和复叶轴为外植体,通过直接器官发生途径,在添加了6-BA、NAA、KT不同浓度的MS培养基上直接诱导不定芽,并进行了暗培养处理。综合不定芽的诱导率和生长状况得出,复叶和复叶轴诱导不定芽的最佳培养基分别为MS+6-BA2.0mg/L+KT1.5mg/L+NAA0.05mg/L和MS+6-BA1.0mg/L+KT1.5mg/L+NAA0.05mg/L,在这两种培养基上诱导分化的芽生长健壮,芽多而高,经过增殖培养后能诱导根的生成;最佳暗培养时间为3周。  相似文献   

19.
20.
对新研发的荼用"叶壮"叶面肥进行了田间试验,对于春茶、夏茶和秋茶进行了3次田间试验,结果证明施用该叶面肥2~4次后,鲜茶叶的产量较对照增产20%以上,而施用双吉尔-GGR的对照增产小于10%.施用该叶面肥后生产的成品茶在茶叶感官评审方面与对照没有差异.茶叶理化指标分析结果表明施用该叶面肥后生产的成品茶在茶多酚、水浸出物、氨基酸和咖啡碱含量指标上均有提高.  相似文献   

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