首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 93 毫秒
1.
正越南槐是广西传统有名的木本药源植物。它对自然气候、地理环境要求苛刻,须在一定高度的石山岩石缝隙里才会存活生长。它的生长周期长,种植后至少3年才能采挖。由于产地不同、采挖季节不同等差异,其有效成分含量达药典标准的合格商品少,供应越来越紧张。越南槐主要以干燥的根及根茎入药,中药名为山豆根。山豆根是一种药用价值较高的药材,为治疗咽喉疾病的传统要药。它临床应用较为广泛,具有清热  相似文献   

2.
3.
苦参碱广泛存在于豆科植物苦参、苦豆子、广豆根、砂生槐树、日本山豆根等中,是我国常见常用中草药一苦参的主要有效成分,我国药典已将“苦豆草片”加以收载,主治痢疾和肠炎。国外对苦参的研究始于20世纪30年代,国内则始于70年代,研究的重点均在生物碱上,到2003年已从苦参中分离出27种生物碱。  相似文献   

4.
正广西九万山国家级自然保护区位于苗岭山脉南缘,是桂北地区重要的生态屏障,面积37.8万亩,其中4万亩是当地群众种植的杉木等人工林。近年来,随着杉木林陆续进入采伐期,社区群众提出了采伐诉求。从2014年起,九万山保护区管理局探索社区共管新模式。先后筹措了800万元资金,用于扶持农民石蛙、禾花鲤、灵芝、草珊瑚和山豆根等生态种养业,帮扶社区建设道路、人畜饮水、漫水桥、候车厅等民生项目。  相似文献   

5.
为给湘南地区千年桐林药间作提供技术支撑,在湘南地区选择已进入盛果期的4年生千年桐,分别设置千年桐+草珊瑚(Ⅰ)、千年桐+玉竹(Ⅱ)、千年桐+山豆根(Ⅲ)、千年桐+金银花(Ⅳ)、千年桐+菊花(Ⅴ)、千年桐纯林(Ⅵ,作为对照)这6种种植模式进行了林药间作试验,观测了不同间作模式下千年桐的产果量、药材产值、林地土壤水文效益和土壤冲刷量,分析了不同间作模式的综合效益。研究结果表明:1)模式Ⅱ和Ⅳ的千年桐单株产果量最高,分别为7.17、7.13kg,其与对照间的差异均显著;2)模式Ⅳ的药材产值最高,每hm2可达10.8万元;3)模式Ⅰ、Ⅲ、Ⅴ的土壤涵养水源能力最强,分别为1799.7、1776.4、1817.2t·hm^-2,且与对照间的差异均显著;4)模式Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ的土壤冲刷量分别为299.3、329.2、396.7、423.7、410.3t·km^-2,都显著低于模式Ⅵ(对照,504.5t·km^-2);5)模式Ⅳ的综合效益最高,而模式Ⅰ、Ⅱ、Ⅲ、Ⅴ的综合效益依次次之,综合效益最差的为模式Ⅵ(对照)。  相似文献   

6.
青檀,为我国特产树种。其适应性强,在石灰岩山场生长良好,较耐旱和瘠薄,根系发达,萌蘖性强,可经营矮林作业以截取枝条。枝皮富有纤维,绵韧易剥,是制造宣纸的特需原料。一、播种育苗青檀种子具有生理休眠特性,且种子个体的休眠深度差异较大。种子催芽方法,一是将种子装入木桶内,  相似文献   

7.
The competition-density (C-D) effects for mean mass for tree, stem, branch and leaf were analyzed in Acacia auriculiformis stands. Mean tree mass-density and mean organ mass-density were well explained by the C-D equation of tree and the C-D equation of tree organ, respectively. An equation describing the relationship between mean leaf area u and density was formulated that fit the u-data well. The relationship between mean tree mass w and the ratio of each organ to mean tree mass (wo/ w) was examined. With increasing w, the stem mass ratio wS/w increased, whereas the branch mass ratio wB/w and the leaf mass ratio wL/w decreased. The yield difference between the lowest-density stand and the high-density stand became greater with stand growth. However, the yield of the mid-density stand was slightly lower than the yield of the high-density stand during the experimental period. To produce the most desirable combination of demanding individual-tree size and relative high stem yield, the mid-density is recommended as proper planting density for future management of A. auriculiformis stands.  相似文献   

8.
《技术与市场》2007,(9):24-24
海藻糖是一种稳定的非还原性双糖,广泛存在于低等植物、藻类、细菌、真菌、酵母、昆虫及无脊椎动物中,既是一种贮藏性糖类,又是应激代谢的重要产物.由于海藻糖是由特殊双糖分子构成的非还原性糖,特性非常稳定,能够在高温、高寒、干燥失水等恶劣的条件下在细胞表面形成特殊的保护膜,有效地保护生物分子结构不被破坏,从而维持生命体的生命过程和生物特征.海藻糖可广泛用于生物制剂、医药、食品、化妆品及农业科学等各个行业.  相似文献   

9.
《技术与市场》2007,(4):26-26
自动取暖保健热宝是传统手炉的替代新产品,该产品不用电可持续供热,它使用方便,价格低廉,是人们冬季的首选暖手用品,也是野外作业人员不可多得的取暖之宝.该产品具有热敷镇痛的功效,深受风湿关节痛、肩周炎、腰腿痛、胃痛等患者的欢迎.该产品每个综合成本1到2元,市场售价8到10元,若日产100个,每个平均利润5元,效益可观,实乃致富好门路.  相似文献   

10.
我国太阳能资源十分丰富,目前最主要的利用方式是用于城乡居民热水供应,我国太阳能热水器已经安装了6000万平方米,预计2020年和2050年将分别达到2.7亿和5亿平方米,将替代高峰电力8000万千瓦和2亿千瓦,节约1200万千瓦和30000亿千瓦时的电能.我国太阳能热水器已经成为太阳能利用中应用最为广泛、产业化发展最迅速的领域,太阳能热水器的生产量和使用量都居世界第一.至2003年底,全国太阳能热水器使用量达到5200万平方米,占全球使用量的40%以上.目前我国太阳能热水器生产厂家超过3000家,年生产量超过1000万平方米,全真空玻璃管热水器在世界市场上占据主导地位.  相似文献   

11.
金佛山濒危抗癌中草药——胡豆莲   总被引:1,自引:0,他引:1  
主要叙述了金佛山濒危抗癌中草药胡豆莲的生物学特征、资源状况,通过分析其濒危原因,提出了相应的保护对策。  相似文献   

12.
分析我国加入WTO后茶业的机遇和面临的严竣问题 ,提出西双版纳茶业发展应加速低产茶园改造 ,推广无性系良种 ;保护茶园生态 ,应用生物技术 ;调整产品结构 ,开拓国内外市场 ;建立龙头产业 ,实施名牌战备等四项建议。随着中国加入WTO步伐的加快 ,为我国茶叶出口创造了前所未有的机遇 ,中国是世界产茶大国 ,19世纪几乎垄断了整个世界茶叶市场 ,进入 2 0世纪 ,肯尼亚、斯里兰卡后来居上。 1999年全国茶叶产量达 6 8万t,出口仅2 0 .2 9万t,云南茶叶产量 7.5万t,出口仅 1.0 3万t,版纳茶叶产量 1.5万t,几乎全部内销。国茶出口不畅 ,其主要原因是受经营机制和产品质量的制约 ,如何抓住中国加入WTO的机遇 ,振兴国茶在国际市场的声誉 ,促进版纳茶业再上新台阶 ,必须认真分析存在的问题 ,改革现行茶叶经营机制 ,依靠科技进步 ,提高产品的产量和质量  相似文献   

13.
14.
15.
16.
Invasion of natural ecosystems by exotic plant species is a major threat to biodiversity. Disturbance to native plant communities, whether natural or management induced, is a primary factor contributing to successful invasion by exotic plant species. Herbivory by both wild and domestic ungulates exerts considerable impact on structure and composition of native plant communities. Intensive herbivory by ungulates can enhance exotic plant invasion, establishment, and spread for three reasons: (1) many exotic plants are adapted to ground disturbances such as those caused by ungulate feeding, trampling, and movements; (2) many exotic plants are adapted for easy transport from one area to another by ungulates via endozoochory and epizoochory; (3) many exotic plants are not palatable or are of low palatability to ungulates, and consequently, their survival is favored as ungulates reduce or eliminate palatable, native plants. Ungulate herbivory is a chronic, landscape-scale disturbance capable of influencing plant communities as much as episodic events such as fire. Consequently, ungulate herbivory has the potential to facilitate the invasion and establishment of exotic plants in the interior Pacific Northwest where ungulates occupy nearly every ecosystem. Moreover, ungulate herbivory has intensified in many ecosystems, owing to the addition of domestic ungulates with that of existing, wild ungulates, coupled with the reduction or elimination of migratory movements and predators that previously regulated wild ungulate populations and influenced their distributions. Despite the observational evidence for ungulate herbivory as a strong facilitator of exotic plant invasion and establishment, current knowledge of cause–effect relations is severely limited by a lack of manipulative experiments. Most studies have been observational, unreplicated, and lack the experimental controls needed to eliminate or account for confounding sources of variation. Heightened attention to conservation of biodiversity will increase the importance of managing ungulates in balance with the plant communities that support them.  相似文献   

17.
This study presents data on the biomass and net aerial primaryproductivity (NAPP) of two contrasting East Anglian salt marshes.One site was at Tollesbury, Essex where the marshes are of theestuarine type and are subject to marsh degradation and erosionwhile the other site was 130 km to the north at Stiffkey, Norfolkwhere the barrier-type marshes are still actively developing withno signs of erosion. The NAPP was determined by the method ofSmalley with quadrats being harvested monthly with replacement.At the lowest levels at Tollesbury there was Pioneer Marshwhich was dominated by a mixture of Salicornia spp. and Astertripolium. At higher levels at Tollesbury there was LowerMarsh which was dominated by a mixture of Atriplex portulacoides andPuccinellia maritima. Over the four years of the studyPuccinellia became the dominant species following a markeddecrease in the extent and vigour of Atriplex. At Stiffkey theMiddle Marsh was at a much higher level and the vegetation waspredominantly a short dense sward with Atriplex portulacoides,Puccinellia maritima and Limonium vulgare together with smallerquantities of Armeria maritima and Plantago maritima. The meanNAPPs over three years of the Pioneer and Lower Marsh atTollesbury (467 & 519 g m-2 yr-1respectively) were similar butin 1993 the NAPPs recorded at Tollesbury were higher than thoserecorded at Stiffkey (625 & 583 compared with 458 g m-2yr-1).Smalleys method is difficult to apply to communities wherespecies dominance is variable, especially when dominance isshared between species with markedly different growth patterns.The results for NAPP obtained from the salt marshes at Tollesburyand Stiffkey are discussed in relation to results obtained byother workers from comparable areas in England and theNetherlands. Attention is also drawn to the possibly largerbelow-ground component of production that is frequentlyoverlooked. The importance of salt marshes in relation to othercoastal communities lies in the export of a proportion of theorganic matter produced and this mainly depends on theabove-ground production.  相似文献   

18.
19.
The Kenyan coastal forests make up one of the World 25 Biodiversity Hotspots. They consist of over 140 fragments (the majority with areas less than 0.5 km2) of the once extensive Zanzibar-Inhambane lowland moist forest. The over 60 known Mijikenda sacred Kaya forests and groves scattered along the coastal hinterland form the greater part of this ecosystem. The forests are of biological and cultural significance, and this has been recognized nationally and internationally, with some now listed as World Heritage Sites. The forests are protected by councils of Kaya elders who regulate use of their resources. Increasing human population and subsequent rise in demand for forest products and land for settlement has put a strain on these relic forests. Farm encroachment and extraction of forest products in different Kaya forests have affected the vegetation ecology at varying levels. This study investigated the spatial species distribution, association and regeneration potential of commonly utilized plants in one of these traditionally managed ecosystems. A modified nested plot method was used to collect data in the field.Using TWINSPAN multivariate, and indicator species analysis, two plant communities (Asteranthe and Bridelia) and an undifferentiated vegetation type were identified. Species association in Asteranthe consisted largely of forest dependant species, with a significant presence of woody climbers. It was comprised of two sub-communities namely Manilkara and Scorodophloeos. In contrast the second plant community, Bridelia, was dominated by light demanding species. It comprised one sub-community (Catunaregam) and a seral stage (Keetia). The species diversity and richness was higher in the Asteranthe community compared to Bridelia. Some of the forest species commonly utilized by the local people were observed to regenerate both in open and closed forest habitats while others had seedling recruitment confined to closed forest.Despite some coastal forests showing physiognomic similarity, detailed study shows intra-variation linked to topography, exposition, type and intensity of human perturbation both currently and in the distant past. Clearly, vegetation patterns of coastal forests of eastern Africa change at fairly short intervals.Recruitment of forest specialists is likely to decline if closed forests are opened up by farm encroachment, however their less specialized counterparts can pioneer in re-colonization of disturbed sites if conservation is strengthened. There is need to invigorate traditional management systems of forests with cultural significance by recognizing and giving increased legal mandates to the local custodians.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号