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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.
近年来,随着榆林煤炭、石油和天然气等矿产资源的大规模开发,神木、府谷的一些地方已经出现地面塌陷、地下水源破坏等自然环境恶化的现象,导致榆林土地沙漠化的趋势有可能向不良方向发展。这不仅威胁着人们的生存生产条件,同时也影响着当地社会经济的可持续发展。本文通过对榆林沙区土地沙漠化现状的分析,提出土地沙漠化防治的对策。  相似文献   

12.
以毛乌素沙地沙柳人工林为研究对象,对人工灌木林平茬年龄、平茬高度及平茬周期进行试验研究。结果表明:沙地沙柳造林后3~6a内应进行首次平茬复壮,进入丰产期后平茬周期以3~4a为宜,此时生物量收获最高;沙柳人工林平茬留茬高度应控制在5cm左右,平茬后生物量积累最快。  相似文献   

13.
朱宇林 《绿色大世界》2012,(5):51-52,55
分析了玉林花卉产业的发展优势、发展现状及生产模式,针对玉林市花卉产业存在的问题,提出了加强政府调控管理、优化生产布局、采用科技手段提高产品竞争力、培养出玉林市的品牌鲜花、引进先进技术和名贵花卉等玉林花卉产业发展对策,以推动玉林现代花卉产业沿着优质、高效的标准化生产道路快速发展。  相似文献   

14.
2015-2018年,在榆林市沿黄生态经济带的吴堡县黄河滩地进行冬枣(Ziziphus jujube cv.dongzao)引种和栽植技术试验,结果为冬枣在当地可安全越冬越夏,生长正常,对土肥水条件要求较高,生长发育期约190~210d,3月下旬前后开始萌动,6月中旬开始结果,7月中下旬果实快速膨大,10月上中旬果实成熟。定植或降树塑形嫁接当年见果,第3年进入丰产期,平均株产10.6kg,平均单果质量可达13 g;栽植应选择地势开阔、光照、土壤等条件较好的地段,采用直接定植或降树塑形嫁接冬枣的方法建园,同时加强土、肥、水管理特别是水肥的有效调控,及时防治病虫害并采收成熟果实。  相似文献   

15.
大果榛子是适于我国很多地区栽植的优良坚果树种,果实营养丰富。本文结合前期在榆林的引种试验结果,收集并参考国内大果榛子栽培管理经验以及榆林市气候特征,主要从品种与栽植地块选择、栽植方式与土壤管理、整形修剪、病虫害防治等方面提出了适于榆林市大果榛子栽培技术。  相似文献   

16.
将数据挖掘技术引入红树林虫害成因分析中,利用广西山口国家红树林生态自然保护区2004—2015年广州小斑螟发生面积数据,分别选取1月和4月平均气温、降水量4个气候因子,采用C 4.5算法在WEKA平台建立决策树模型,预测2016、2017年广州小斑螟发生面积,并检验实际发生情况。结果表明,对广州小斑螟发生影响力由大到小依次为1月降水量,1月平均气温,4月平均气温,4月降水量;该模型分类正确率较高,预测2016、2017年广州小斑螟发生情况与实际情况总体一致。  相似文献   

17.
提高榆林沙区飞播造林治沙成效的研究   总被引:2,自引:0,他引:2  
飞播治沙造林种草作为治理榆林沙区的一项主要技术得到了大面积的推广应用,并已取得了明显成效。本文根据近年来榆林沙区飞播治沙造林情况,就现阶段飞播治沙造林中的几个关键技术进行了初步研究,对提高榆林沙区的飞播成效、加快该地区沙地治理速度具有一定的意义。  相似文献   

18.
本文通过实地调查,分析了榆林沙棘资源利用现状及在产业化开发中存在的问题。研究认为,榆林沙棘资源丰富,是沙棘适生区。但品种单一,栽植技术落后、规模化种植程度低、功能产品开发基础薄弱等制约了沙棘资源利用。以政府为主导,市场为导向,科技创新,规模发展的产业化发展措施是实现沙棘产业健康、稳定和可持续发展之路。  相似文献   

19.
榆林市地理位置优越,蜜粉源植物资源丰富,这些蜜粉源植物不仅是发展养蜂业非常有利的条件,而且提供给人们粮食、水果、牧草等。分析了榆林市境内主要蜜粉源植物的资源现状,并就养蜂业的可持续发展问题作了初步探讨。  相似文献   

20.
通过对榆林沙区植被恢复建设调查和大量文献资料的查阅,分析了近50年来榆林沙区植被建设所取得的成就以及适合该区发展的模式,即生态工程发展模式和农林复合经营模式;指出了植被建设过程中存在的主要问题,即土地利用类型复杂,沙漠化土地严重和资源分布不均,林业发展不平衡等;提出了相应的解决方法和主要应对措施,即积极引进和推广抗旱优良林草新品种,搞好抗旱节水造林新材料、新技术的示范推广。  相似文献   

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