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中国蜡梅品种分类研究综述 总被引:1,自引:0,他引:1
该文概述了蜡梅品种种质资源分布情况,在综述蜡梅品种分类研究现状的基础上,总结了现行的5个蜡梅品种的分类体系,并对今后一段时期蜡梅品种分类研究工作的侧重点提出了一些建议。 相似文献
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正在大巴山南麓的四川省万源市,有一位老人23年来与林结缘,爱林、护林并17年坚持创建蜡梅多样性保护园区,使之成为我国资深专家、科研院所向往、研究首选之地。这位老人就是万源市青沟蜡梅园园主、年过七旬的楚恩寿。二十三年与林结缘1947年,楚恩寿出生在万源市太平镇。1968年,他走进军营,两年的军旅生涯锻造了他坚韧而执着的品质。复员后,他干过煤矿工人、承包过水泥厂、经 相似文献
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《林业科学》2016,(12)
【目的】比较蜡梅属5种植物花中挥发性成分组成的差异,探讨5种植物之间的亲缘关系和系统分类意义,为蜡梅属植物的资源利用提供理论依据。【方法】采用顶空固相微萃取(HS-SPME)方法处理样品,并优化前处理条件,结合气相色谱-质谱联用(GC-MS)技术测定蜡梅属5种植物干花中的挥发性成分,比较5种植物花中的成分差异,并应用SIMCA-P+11.0软件进行主成分分析,通过得分图直观地表达蜡梅属5种植物间的相互关系。【结果】通过优化样品处理得出HS-SPME最佳的萃取条件为:样品用量1.2 g,加热温度70℃,吸附时间45 min,解吸时间3 min。通过GC-MS测定并定性分析,从蜡梅属5种植物干花中共鉴定46种挥发性物质,其中蜡梅37种、突托蜡梅41种、山蜡梅41种、浙江蜡梅36种和柳叶蜡梅43种,且5种植物花中的共有成分达到24种;从鉴定的成分来看,蜡梅属植物花的挥发性成分主要以萜类成分为主,包括萜烯、萜醇、萜酯等含氧衍生物及少数脂肪族化合物。蜡梅花中主要含有乙酸芳樟酯、黑蚁素及石竹烯氧化物等挥发性成分;柳叶蜡梅、浙江蜡梅和山蜡梅中主要挥发性成分有α-月桂烯、桉叶素和四甲基环癸二烯甲醇;突托蜡梅花中桉叶素、黑蚁素和异香橙烯环氧化物等成分含量较大。通过主成分分析,蜡梅属5种植物明显被划分为3类,其中浙江蜡梅、山蜡梅和柳叶蜡梅3种植物挥发性物质组成相似,归为一类;而蜡梅和突托蜡梅分别与另外3种植物花的挥发性成分的组成差别较大,各自聚为一类。主成分分析结果与蜡梅属5种植物的系统分类学研究结果一致。【结论】蜡梅属5种植物花的挥发性成分主要以萜类成分为主,且成分组成差异较大,其中柳叶蜡梅、浙江蜡梅及山蜡梅花的挥发性成分相似,具有相同的资源利用性;蜡梅及突托蜡梅花香气各异,挥发性成分组成明显不同于另外3种植物,在资源利用上可区别对待。本研究结果可为蜡梅属植物的分类学研究提供基础理论依据,也为蜡梅属花资源的开发利用提供理论参考。 相似文献
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蜡梅为我国的传统名花,具有极高的观赏价值和经济价值,是园林绿化、切花、花茶、盆景、香精等的好材料。作为蜡梅主产地之一的重庆,其蜡梅栽培范围广,品种资源丰富,主要应用于绿化、切花、花茶等方面。在对重庆蜡梅品种资源和产业调研的基础上,从资源状况、产业现状、发展优势、产业定位等方面,指出重庆蜡梅在资源研究和应用上的不足,并提出了相应的发展对策。 相似文献
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Chinese pine (Pinus tabulaeformis Carr.) seedlings were raised for 22 weeks in tubes of both plain kraft paper and kraft paper with a thin polyethylene film coating on one side. Some containers of each type were made from paper impregnated with cupric sulfide. Both copper-impregnated and untreated kraft paper decomposed completely within three months. Roots of adjacent seedlings in untreated paper tubes, without a polyethylene coating, became extensively intermeshed and could not be separated without damage. Root intermeshing did not occur among seedlings raised in tubes of untreated polyethylene coated paper, but the polyethylene barrier caused root spiralling. Although impregnating the containers with cupric sulfide did not prevent paper decomposition, it prevented root spiralling in paper tubes with a polyethylene coating, and root intermeshing by adjacent seedlings in paper tubes without a polyethylene coating. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1-4):54-65
Analysis of consumer demand for packaging suggests that: plastic packaging is a luxury good, while paper packaging is a normal good, paper packaging demand increases with the price of plastic packaging, and that demand for paper packaging is most sensitive to its own price, and to the income of consumers. In a complementary analysis of input demand in the converting paper industry it was found that the demand for each paper grade is price inelastic, capital and other materials are substitutes for paper, while labor is a complement, technical change rapidly decreases the use of unbleached kraft packaging and industrial converting, and increases the use of other grades. The demand for each paper grade, derived from the consumer demand and the factor demand functions, showed that, from 1983 to 1991, the demand for paper in packaging was influenced mainly by consumer income, and by the price of paper packaging, and less so by the price of paper itself, or by the price of plastic packaging. 相似文献
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经济发展和科技进步提高了我们的生活水平和质量,干法无尘蓬化软纸(无尘纸)这类新型纸种主要在一次性卫生用品领域得到了应用和发展,方便了我们的生活,但该种纸的生产在我国还没有得到充分发展,高档产品基本依赖进口。笔者意在通过对该纸种生产工艺及其国内市场应用情况的分析,达到倡导此纸种在我国的生产和应用的目的,从而促进我国生活用纸的进一步发展,为百姓提供更多的生活便利。 相似文献
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为研究富阳竹纸的耐老化性能,选取杭州富阳逸古斋元书纸有限公司生产的超级元书、二级元书、冬纸壹号及古籍修复纸这4种富阳手工竹纸进行干热加速老化试验。基于样品的D65亮度、抗张指数、断裂伸长率、表面pH及热稳定性等理化性能指标在老化过程中的变化情况,分析富阳竹纸的耐老化性能。试验结果表明:所有竹纸样品的D65亮度在老化过程中发生了不同程度的下降,其中经过纯碱二次煮料或化学漂白的竹纸,老化前后D65亮度的变化相对较小,即竹纸的D65亮度稳定性与纸浆的处理程度呈正相关。但经过多次煮料和化学漂白的竹纸,其热稳定性在老化后发生小幅度的下降,说明工艺处理程度过大会影响竹纸的热稳定性。强度方面,初始抗张指数较高的竹纸,经老化后仍保留较好的强度性能。在老化过程中,所有竹纸样品的pH均逐渐降低,其中化学漂白竹纸的下降幅度最大,即化学漂白会加速竹纸的酸化。4种富阳竹纸的耐老化性能存在差异:冬纸壹号各方面的性能在老化过程中相对比较稳定,超级元书的各项性能经老化后发生了一定程度的下降,二级元书的强度稳定性和热稳定性能较好,古籍修复纸的D65亮度稳定性最好。 相似文献
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我国木材贫乏,而竹类富饶,因此许多人认为,以竹代木发展造纸业势在必行,作者认为,对发展竹材造纸业必须谨慎,理由:我国以竹为主的手工造纸业是在洋纸冲击下衰落的;近几十年,我国竹材机械造纸有过起飞机会,但发展非常缓慢;印度是世界竹材造纸业最发达的国家,而木材却有可能取代竹材的地位;60-80年代,东南亚不少国家曾发展竹材造纸,现在除个别国家外,都停止了。 相似文献
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In northern Laos, shortened fallows in the slash-and-burn upland rice system are not sustainable either from a production
or economic standpoint. This paper evaluates the potential for using the indigenous fast-growing tree, Broussonetia papyrifera L. Vent. (paper mulberry) as an economic fallow crop. The objectives of this study are to assess the inner bark yield of
paper mulberry, and to evaluate rice productivity following paper mulberry cultivation. In addition, allometric models for
estimating the inner bark yield of paper mulberry are developed. Inner bark yield of paper mulberry stands ranging in age
from 9 to 48 months ranged from 10 to 208 g m−2, and increased with age. The models using diameter at breast height and stem height, or diameter at breast height only as
independent variables explained well the variation in inner bark yield. When paper mulberry was completely removed during
the rice growing season, rice yields in these areas were similar to those following weedy bush fallow. When paper mulberry
was allowed to grow, rice yields were negatively correlated to paper mulberry stem density. When paper mulberry lateral branches
were pruned back, rice yields could be maintained if the paper mulberry stem density was <0.22 stems m−2, suggesting that if paper mulberry is managed properly, rice yields can be maintained at current levels. The paper mulberry-upland
rice rotation system improves the productivity of a traditional slash-and-burn system through harvesting paper mulberry inner
bark; however the long-term sustainability of such a system remains unclear and warrants further investigation. 相似文献
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随着我国产品的商业附加值迅速提升,纸质包装机械生产企业的产能出现阶段性过剩,如何实现纸质包装机械生产企业去产能,成为许多企业亟待解决的问题。论述了我国包装纸行业概况,分析了包装纸机械市场需求,在此基础上,提出了纸质包装机械生产企业去产能措施。 相似文献
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ABSTRACT China is the largest importer of waste paper in the world and is highly dependent on the international market. Thus, the relationship between Chinese and international waste paper markets affects the supply of fiber materials in China’s paper industry. This study examined the dynamic relationship between the two markets and the impact of newly implemented policies on both markets. We used unit root tests, cointegration test, vector error correction model (VECM) and frequency-domain Granger causality test to investigate the integration between Chinese and international waste paper markets and identify which of the two markets is the price leader. The results revealed that the two markets were integrated after controlling for structural breaks, and the Chinese market acted as the price leader. Since the supply of waste paper and wood pulp is insufficient in China to meet the fiber demand of the paper industry, waste paper import restrictions have significantly affected the supply of fiber materials in China’s paper industry. Therefore, the Chinese government should fully consider the benefit of market integration and make full use of international waste paper resources to satisfy the large domestic demand for paper products. 相似文献