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1.
“红雪茶”和“白雪茶”是滇西北少数民族传统饮用的地衣保健茶;其中,“红雪茶”混杂了梅衣科(Parmeliaceae)金丝属(Lethariella)中的4个地衣种:金丝绣球(Lethariellacashmeriana),金丝刷(L.cladonioides),柔金丝(L.sernanderi)和金丝带(L.zahlbruckneria);“白雪茶”包含了雪茶属(Thamnolia)中的两个种,即:雪茶和雪地茶(Thamnoliavermicularis&T.subuliforms)。利用常规方法测定了两种地衣茶的主要营养成分,并与常见饮茶进行比较,测定结果显示:红雪茶和白雪茶含有多种营养成分,红雪茶粗蛋白质含量为2.69g/100g·DW,粗脂肪3.42g/100g·DW,总糖、可溶性糖、灰分含量分别为5.04g/100g、0.35g/100g、1.74g/100g·DW;白雪茶的粗蛋白质含量为2.81g/100g·DW,粗脂肪2.91g/100g·DW,总糖、可溶性糖、灰分含量分别为0.99g/100g、0.27g/100g、4.18g/100g·DW;两种地衣茶均含有17种氨基酸和多种矿物元素,具有一定营养价值;而两种地衣营养成分的含量存在差异。  相似文献   

2.
中国血竭基源植物的研究与利用   总被引:2,自引:0,他引:2  
血竭是我国传统名贵中药,目前商品血竭主要来源于棕榈科黄藤属(Daemonorps)植物的果实和百合科龙血树属(Dracaerta)植株茎干的红色树脂.在我国境内发现的、有野生分布的血竭基源植物只为海南龙血树和剑叶龙血树两种.系统综述了我国血竭基源植物的资源状况、血竭形成机理、血竭基源植物的开发利用、人工繁育及栽培技术等方面的研究进展,并对野生血竭基源植物资源的保护、开发与利用、血竭产生机制的研究等进行了展望.  相似文献   

3.
雪茶化学成分研究   总被引:14,自引:0,他引:14  
由管枝衣科地茶属植物雪茶(Thamnolia vermicularis)丙酮提取物中分离得到10个成分,通过波谱分析及与已知品对照等方法,最终确定其中的9个化合物分别为:Thamnolin(1),鳞片衣酸(2),坝巴酸(3),羊角衣酸(4),3β-羟基-5α,8α-桥二氧麦角甾-6,22-二烯(5),3β-羟基-5α,8α-桥二氧麦角甾-6,9,22-三烯(6),麦角甾烷-7,22-二烯-3-醇(7),麦角甾烷-5,8,22-三烯-3-醇(8),亚油酸(9)。其中,化合物1为新化合物,化合物3和6-9系首次由该种植物中分离得到。研究结果初步明确了云南中甸地区产雪茶为主要含有坝巴酸(3)和羊角衣酸(4)等酚性成分,而非主含地茶酸等酚性成分的植物品种类型,这为合理开发利用当地植物资源提供了科学依据。  相似文献   

4.
雪茶     
雪茶杨世诚在我国云南、四川、陕西等地的高寒山地,生长着一种粉丝状的藻菌营养体,这就是珍贵的雪茶(Thamnoliavermicularis)。雪茶是地衣植物,属于地茶科。它滋生于特定的环境里,海拔4000-5000米的高山雪线地带是其生生不息的家园。...  相似文献   

5.
为了解物种和基物偏好对地衣元素水平的影响,测定了采集于河北太行山区6个地点的6种地衣体内的16种元素(Al、Ba、Cd、Cr、Cu、Fe、Mn、Mo、Na、P、S、Sc、Sr、Ti、V和Zn)的含量。这6种地衣包括3种石生地衣(鸡冠胶衣Collema cristatum、中国石黄衣Xanthoria mandschurica和淡腹黄梅Xanthoparmelia mexicana),2种土生地衣(莲座石蕊Cladonia pocillum和石果衣Endocarpon pusillum),及1种树生地衣(毛边黑蜈蚣衣Phaeophyscia hispidula)。主成分分析(PCA)和费里德曼双向秩方差分析(Friedman检验)结果显示,物种和基物偏好对地衣体内元素含量的影响显著,而地点的影响不显著。树生地衣累积的大气源元素(P、S和Zn)高于土生和石生地衣。土生地衣体内的地壳源元素(Al、Ba、Fe、Mn、Mo、Na、Sc、Sr、Ti和V)和大气源元素Cr的含量最高。石生地衣的大气源元素(P、S和Zn)含量近于土生地衣,但地壳源元素含量较低;3种石生地衣在这些元素的含量方面差异不大。这些结果表明以地衣化学组成监测大气元素沉降的研究需慎重考虑物种及基物偏好的影响。  相似文献   

6.
目的:摸清贵州古茶树资源组成与分布,为区域古茶树资源保护、利用提供基础。方法:采用线路调查的方法,对贵州省内古茶树进行全面调查,利用地理信息系统和统计学分析贵州古茶树资源种类组成、地理分布特征、年龄结构特征及生长状况。结果:(1)资源调查涉及338个分布点,记录了7 816株古茶树,隶属5种2变种;(2)赤水河-綦江水系是疏齿秃房茶现有分布中心、乌江水系是茶现有分布中心、都柳江水系是突肋茶现有分布中心;(3)古茶树垂直分布于海拔200 m到2 500 m之间,随着海拔升高,分布的物种数越多,在1 000~1 500 m海拔段物种数量达到峰值,随后海拔越高物种数越少;(4)古茶树树高一般在10 m以下,地围在20~100 cm的居多,平均冠径集中在3 m以下,绝大部分古茶树生长势正常,也存在因生境影响而处于衰弱或濒危状态。结论:调查显示贵州古茶树资源共7种,含5种2变种,存在疏齿秃房茶、茶、突肋茶等3个物种的现有分布中心。古茶树生长状况良好,少数处于衰弱或濒危状态,亟需加强古茶树保护与管理力度。  相似文献   

7.
对云南地区栽培的大叶茶(Camellia sinensis var. assamica)9个居群和大理茶(C.taliensis)3个居群的遗传多样性和居群遗传结构进行了比较研究。通过对94条叶绿体DNA RPL32-TRNL序列的核苷酸序列变异进行分析,共发现了7个单倍型。研究结果表明,大叶茶(h=0.728,π=0.00469)比大理茶(h=0.610,π=0.00225)拥有更为丰富的遗传变异,但其居群遗传分化水平(Gst=0.580,FST=0.612)却低于大理茶(Gst=0.696,FST=0.773)。AMOVA分析进一步证实了它们的遗传变异主要存在于居群间,且大叶茶(61.21%)低于大理茶(77.34%)。相对于大理茶,遗传多样性水平在本研究所取的大叶茶居群间存在着较大的差异,单倍型多态性水平变化范围为0~0.809,核苷酸多态性水平变化范围为0~0.00487。最后,讨论并提出了科学有效地保护我国古茶园茶种资源的建议和对策。  相似文献   

8.
兴国红鲤和荷包红鲤是宝贵的红鲤品种,作为优良杂交亲本,广泛应用于品种改良和新品种的选育。由于形态相近、差异较小,在选择杂交亲本的过程中,极易发生两种红鲤的混淆,影响新品种的养殖经济效益。通过阅读参考文献,使用数据库位点挑选和性状基因位点挑选,获得了8个SNP候选标记,理论上使用7个SNP标记,即可实现两种红鲤的鉴别,且鉴别错误率为6.30E-05,这对以两种红鲤为杂交亲本的新品种选育及养殖效益的提升意义重大,也有利于两种红鲤的种质资源保护。  相似文献   

9.
红基盘瓢虫和红星盘瓢虫实验种群生命表的初步研究   总被引:1,自引:0,他引:1  
本文组建了红基盘瓢虫和红星盘瓢虫的实验种群生命表,并应用Morris模式探讨影响种群数量变动的主要因子;计算了两瓢虫的内禀增长率(r_m)及其它有关的生态学统计量。在实验室条件(平均温度29.5±1.5℃和相对湿度70.0±4.9%)下,红基盘瓢虫和红基盘瓢虫的内禀增长率(r_m)、周限增长率(γ)均相近,而两者的种群趋势指数(I)、净繁殖率(R_0)和世代平均历期(T)差异较大。红基盘瓢虫的内禀增长率r_m=0.0841,种群数量以每8.2天增长一倍的速率发展;红星盘瓢虫的内禀增长率r_m=0.0887,种群以每7.8天增长一倍的速率发展。生殖力减退是影响两瓢虫实验种群数量变动的主要因子。在盛夏进行两瓢虫的大量繁殖并应用于橄榄星室木虱的防治是可行的。  相似文献   

10.
白莺山古茶的化学成分分析与栽培茶树的起源   总被引:3,自引:0,他引:3  
应用高压液相色谱(HPLC)技术,对白莺山古茶的大理茶素、儿茶素类、茶掊素、没食子酸、咖啡因和茶氨酸的含量进行分析.同时,应用分光光度法测定茶多糖和茶多酚含量.在与野生大理茶及栽培大叶茶(普洱生茶)进行多成分比较的基础上,结合形态性状的变异与进化,讨论白莺山古茶种质资源的多样性与野生大理茶和栽培大叶茶的相互关系.分析研究结果不仅为白莺山古茶的品质评价提供可靠的科学数据,为白莺山丰富的古茶种质资源的深人系统研究和合理开发利用提供基础,同时,通过多种过渡类型的化学成分分析与比较,为栽培大叶茶的起源和大理茶作为大叶茶的野生基源之一的假说提供了植物化学方面的证据.  相似文献   

11.
The textual criticism of original species of Hongxuecha has been made combining species identification and field surveys. The results showed that Hongxuecha had two original species, Lethariella cladonioides and L.zahlbruckneri. There were chemical variability within the two populations. Hongxuecha in the market sales included four chemical races of the two species. The distribution center of Hongxuecha was mainly in the southeastern Tibet, western Sichuan and northwestern Yunnan. Currently, Hongxuecha resources have been greatly damaged and species are facing extinction. To enhance effective protection for wild hongxuecha resources, some proposals were presented.  相似文献   

12.
Ecologists have had limited success in understanding which introduced species may become invasive. An evolutionary model is used to investigate which traits are associated with invasiveness. Translocation experiments were simulated in which species were moved into similar but evolutionarily younger communities. The main findings were that species that had previously been the most abundant in their original communities have significantly higher rates of establishment than did species that had previously occurred at low abundance in their original community. However, if establishment did occur, previously abundant and previously low-abundant species were equally likely to become dominant and were equally likely to exclude other species from their new community. There was a suggestion that the species that were most likely to establish and exclude others were 'genetically' different. When species that had evolved in different simulations (but with identical environmental conditions) were transplanted into communities that had also evolved in different simulations of the same conditions, the outcomes were difficult to predict. Observed rates of establishment and subsequent competitive dominance were observed to be species- and community combination-specific. This evolutionary study represents a novel in silico attempt to tackle invasiveness in an experimental framework and may provide a new methodology for tackling these issues.  相似文献   

13.
We aimed at identifying probabilistic areas of high biodiversity value over a large spatial scale, e.g., an entire country (France) within the temperate region, that could work as valuable conservation areas for both rare and common species. We aimed at identifying areas where four measures on bird community overpass a selected threshold value, by using probability interpolation models. The four variables considered were the rare species number, and three measures related to common bird community: relative abundance, estimated species richness and composition originality. For the latter, we developed an indicator that discriminates original from more ordinary compositions of common bird communities, accounting for the number of representatives in each species. This indicator was positively correlated to rare breeding species number, so that original composition of common bird communities allows us to identify areas also supporting the rarest species. Areas with high probabilities of two indicators reaching their threshold values represented 2.9% of continental France. Most double-indicator areas were those with high species richness and high relative abundance, then with original communities and high rare species number. The originality indicator was revealed valuable to identify the most suitable areas that could ensure the preservation of both rare and common species, at a national scale. By preserving sites supporting original common bird communities, conservationists would ensure the protection of rare and common species.  相似文献   

14.
The family Gesneriaceae comprises ca. 150 genera and 3000 species, distributed in the tropics around the world. It is constituted of herbs, lianas, or shrubs, frequently with ornamental potential, due to the beauty of their flowers. Some species have been used in traditional medicine, mainly against fever, cough, colds, snakebite, pains, and infectious and inflammatory diseases. Although Gesneriaceae are a large family, only few species were chemically investigated, and this took place mainly in the last decade. In the present work, chemical and pharmacological studies on Gesneriaceae are reviewed based on original articles published. Altogether 300 compounds have been reported in Gesneriaceae species, including flavonoids, terpenes and steroids, phenolic glucosides, simple phenolics, quinones, lignans, xanthones, and compounds with unusual skeletons. Several species had been used in folk medicine, and some constituents have shown biological activities, such as antimicrobial, anti‐inflamatory, antioxidant, and antitumor properties.  相似文献   

15.
Species loss leads to community closure   总被引:1,自引:0,他引:1  
Global extinction of a species is sadly irreversible. At a local scale, however, extinctions may be followed by re-invasion. We here show that this is not necessarily the case and that an ecological community may close its doors for re-invasion of species lost from it. Previous studies of how communities are assembled have shown that there may be rules for that process and that limitations are set to the order by which species are introduced and put together. Instead of focusing on the assembly process we randomly generated simple competitive model communities that were stable and allowed for two to 10 coexisting species. When a randomly selected single species was removed from the community, the cascading species loss was recorded and frequently the resulting community was more than halved. Cascading extinctions have previously been recorded, but we here show that the relative magnitude of the cascade is dependent on community size (and not only trophic structure) and that the reintroduction of the original species lost often is impossible. Hence, species loss does not simply leave a void potentially refilled, but permanently alters the entire community structure and consequently the adaptive landscape for potential re-invaders.  相似文献   

16.
1. North‐eastern Spain is a hot spot for the introduction of alien fish species, and its native fish fauna is one of the most endangered worldwide. We used an extensive data set from 2002 to 2003 and historical information from the area to characterize fish diversity and establish conservation priorities in river catchments. 2. Diversity indices were used to characterize fish diversity at the basin scale. An index of conservation status was applied for each species, which considers the occurrence, abundance and endemicity of each taxon. We used indirect ordination methods to test the relationship among basin features and to identify those variables most correlated with each other. To identify physical, biotic and environmental characteristics that seem to make a basin particularly susceptible to invasion, we performed a step‐wise multiple regression to examine the relationship between the number of native, translocated and introduced fish species (including the original native species richness of each basin), and landscape variables. 3. Over a period of approximately 50 years, the mean range size of native fish species has decreased by 60%. The greatest decline occurred in Gasterosteus gymnurus, Anguilla anguilla and Salaria fluviatilis, for which species over 75% of the original distribution area has been lost. The species with the highest conservation index were Gasterosteus gymnurus and Salaria fluviatilis. 4. Basin area and the catchment type explained 70% of variation in native species richness, whereas the number of dams and basin area accounted for more than 80% of variation in the number of introduced species. 5. The original native species richness and the number of introduced species at basin scale were not related, and thus there was no evidence of “biotic resistance” to invasion. The restoration of natural hydrologic processes and the development of specific management tools to protect native species, such as the prioritization of areas for fish conservation and the eradication of local populations of exotic species, are required to restore native fish fauna in these catchments.  相似文献   

17.
Investigations were conducted to determine whether ploidal changes found in laboratory cultures of Spirogyra also occur in nature. In an earlier study filament types identifiable as three different species (Spirogyra singu-laris Nordstedt, S. communis (Hassall)Kütz., S. fragilis Jao) arose from an original clonal culture through vegetative growth and sexual reproduction. These three “species” or filament groups differed in filament width, chloroplast number, zygospore size, and chromosome number. The differences in chromosome number represented a polyploid series of diploid (S. communis), triploid (S. fragilis), and tetraploid (S. singularis) forms in which width increased with ploidal level. The three width groups constituted a “species complex.” Five years after isolation of the original strain in this species complex, filaments corresponding to two of the width groups (S. singularis and S. communis) were found at the original collection site in the Santa Catalina Mountains in southern Arizona. The two field-collected groups were indistinguishable from the laboratory species complex in morphology and chromosome number. Homothallic conjugation within the two field width groups yielded progeny similar to those from homothallic conjugation of groups in the laboratory species complex. Filament widths of progeny were generally within the width limits of respective parental groups. The four possible intergroup crosses between the two laboratory and two field width groups yielded progeny similar to the wider parent (S. singularis) or the parent of intermediate width (S. fragilis). Progeny characteristics were determined by the width groups of parents, regardless of whether parents came from the laboratory or field. The similarities in morphology, chromosome numbers, and reproductive behavior of laboratory and field width groups imply that the laboratory species complex of S. communis has a natural counterpart in the field.  相似文献   

18.
系统研究了南方5个亚热带森林生态系统地表植被的动态变化情况.研究方法是:在每个研究区域内,按照地形梯度分别布设50个1m2 的样方,记录样方内所有物种的频度及相关的环境变量,5个研究区域共设250个样方,每个样方分别调查两次.通过单元及多元统计方法分析表明:维管植物物种频度在一个区域明显下降,另二个区域显著增加;苔藓物种频度在一个区域有明显下降,另一个区域明显增加;苔藓物种数量在3个区域显著增加,另二个区域显著下降;维管植物物种数量显著增加在二个区域;物种组成沿着第一个植被梯度轴DCA 1没有显著变化,沿着第二个植被梯度轴DCA 2在二个区域有显著变化.综合分析表明,苔藓对气候变化及其波动反映敏感,是较好的气候变化及气候波动生物指示因子,而管植物数量及频度的变化没有明显证据显示与土壤酸化和大气污染有紧密关系.  相似文献   

19.
通过形态解剖、化学显色反应(CT)及薄层层析法(TLC)对中国地茶属地衣:地茶(Thamnolia vermicularis(Sw.)Ach.ex Schaer.)和雪地茶(Thamnolia subuliformis(Ehrh.)W.L.Culb.)及其种下变型进行了形态分类和特征化合物研究。结果显示,2个变形在形态上均与原变形之间无明显界限,存在过渡形态,并且化学成分也均与原变形一致,因此合并了2个种下变型。通过分析地茶属地衣的分类特征,对地茶属2个种的分类界限进行了重新界定,讨论了我国地茶属的地理分布。  相似文献   

20.
1992年1月对新西兰东木山树木园引种栽培的近100种中国原产树种的生长量调查分析表明:引入地与原产地具有相似的气候条件,尤其是从夏雨型环境向冬雨型环境引种树种,是引种成功的主要原因。  相似文献   

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