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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.
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   

10.
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   

11.
农林复合模式蒸散耗水的研究   总被引:12,自引:0,他引:12       下载免费PDF全文
应用土壤分层水量平衡模型,对林带与冬小麦的根系吸水量、林带和农田的蒸散耗水量、林带影响农田土壤水分范围与程度进行了研究,结果表明:(1)冬小麦拔节至乳熟期间,林带根系吸水以消耗农田土壤水分为主,主要表现在0.0~1.5H(H为树高)范围内。(2)林带可降低12.3%的农田蒸散量。(3)由于林带的影响,在农田中,0.0~0.5H为土壤水分降低区,0.5~5.0H为土壤水分提高区。总体平均,0~200cm农田土壤贮水量可提高11.2%。  相似文献   

12.
以湖南工业大学为例,探讨高校园林绿地景观规划设计的原则、构思、方法。以期对当今高校园林绿地规划设计提供一种思路。  相似文献   

13.
海南岛地处北纬°′~°′,东经 18102010°′~°′,属热带季风气候,适宜香1083711003草兰生长。年,华南热带作物科学研究院刘松1962泉教授从斯里兰卡引种墨西哥香草兰到海南岛儋州种植,多年来只开花不结果。年,在福建省亚1983热带作物研究所和云南省热带作物科学研究所引种试种成功的鼓舞下,华南热带作物科学研究院从广东粤西亚热带作物试验站引进香草兰茎蔓条,试100种于海南万宁县兴隆试验站(现为热带香料饮料研究所,下称香饮所),按福建种植模式并改进为荫棚集约栽培。年,该站《香草兰在海南兴隆地1987区引种试种研究》项…  相似文献   

14.
美国黑莓快繁技术研究   总被引:7,自引:5,他引:7  
采用组织培养方法对美国黑莓主要栽培品种进行培养。通过试验,筛选出一种高效防褐化剂和几种适宜的芽诱导、增殖及生根培养基。并且实验达到了黑莓工厂化育苗的技术要求,为黑莓优良品种提供了快速繁殖的新技术。  相似文献   

15.
以南方山地森林为研究对象,选取有代表性的4个小班,分别采用角规抽样调查法、中心样圆法、样圆群法、六株木法、垂直样带法、标准地法共6种方法对小班蓄积量进行测定,并从6种方法的调查精度、误差大小、工作量及工具和仪器的难易程度等方面对小班蓄积量进行了对比分析,认为角规抽样调查法是最适合南方山地森林小班蓄积量的调查方法。  相似文献   

16.
食用菌多糖研究进展   总被引:15,自引:0,他引:15  
对食用菌多糖的提取、分离纯化、定性定量分析、活性研究和临床应用等研究进展进行了综述,指出了目前存在的不同食用菌多糖较难鉴别、真菌多糖提取纯化工艺需进一步加强、食用菌多糖结构和功能之间的关系问题,提出真菌多糖的提取工艺和构效关系是今后研究的主要方向.  相似文献   

17.
生态旅游对生态环境影响评价   总被引:6,自引:0,他引:6  
阐述生态旅游与传统旅游的不同,结合目前生态旅游的发展状况.以广东鼎湖山自然保护区开展生态旅游为例.分析生态旅游业的兴盛对生态环境的影响,并给出对策。  相似文献   

18.
19.
应正交设计对美登叶面施肥试验结果分析得出,施肥种类是影响百果重的主要因素,施肥次数是影响株产果重的主要因素。单株产量是影响蓝莓浆果总产量的最重要因子,因此应选取单株产量最大的组合,即A1B1C1D1,施硫粉150 g.n-1和木醋原液,浓度200倍,1~2次。  相似文献   

20.
根据科尔沁沙地生态系统退化的现状,提出了本地区生态工程建设的出发点和重点内容,并介绍了一些在工程建设中成功的经验和技术。提出了今后本地区生态建设的方向。  相似文献   

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