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1.
Willow herb tea or preparation are available and relatively popular in the European market, and claimed to be effective inter alia because of their anti-inflammatory activity. The present study is therefore aimed at comparing the anti-inflammatory and antioxidant activity of extracts of the three most popular Epilobium species (E. angustifolium, E. hirsutum and E. parviflorum) and at juxtaposing this activity against the dominating compounds from the following extracts: oenothein B (OeB), quercetin-3-O-glucuronide and myricetin-3-O-rhamnoside. The phytochemical analysis of the extracts has shown that OeB quantities vary between 20% and 35%, while flavonoids content does not exceed 2%. All extracts have inhibited the activity of hyaluronidase and lipoxygenase with IC50 around 5 μg/ml and 25 μg/ml. The inhibition of hyaluronidase is related with the presence of OeB, a strong inhibitor of this enzyme (IC50 1.1 μM). Additionally, the extracts inhibited myeloperoxidase (MPO) release from stimulated neutrophils. OeB inhibited MPO release similarly to the anti-inflammatory drug indomethacin with IC50 7.7 μM and 15.4 μM, respectively. Tested extracts significantly reduced the production of reactive oxygen species (ROS) from f-MLP and PMA induced neutrophils with IC50 5 μg/ml and 25 μg/ml, respectively. The flavonoids content seems to exert little influence on extracts’ activity, contrary to OeB, whose high concentration explains the activity of extract obtained from Epilobium. Tested currently marketed Epilobium preparations are often wrongly assigned, but we should stress that the level of OeB in all tested herbs was high and always exceeded 2% in raw material.  相似文献   

2.
Abstract. Seed production, composition of the seed rain, germination, and seedling mortality, as well as vegetative growth characteristics of common pioneer plant species were studied on the foreland of the retreating Morteratsch glacier in the Swiss Alps. The frequency of diaspores trapped in different successional stages was related to their dispersal mode and was highly skewed towards a few species. Plenty of diaspores well adapted for dispersal by wind are a precondition for the most important pioneer species. Seeds from all pioneer species investigated had a good germination success, provided that the moisture content of the soil was high enough. However, requirement for seedling establishment differed among sites of increasing terrain age and among species. Only specialized pioneers such as Cerastium pedunulatum, Linaria alpina, Oxyria digyna and Saxifraga aizoides tolerate the cold and moist conditions near the glacier. However, these species are restricted to early successional stages. Seedlings of Epilobium fleischeri are affected not only by the cold and moist conditions near the glacier but also by moderately dry conditions on older sites. Availability of safe sites becomes crucial for most species with increasing age of sites and with drier conditions. Most species playing a dominant role during early succession and persisting during later successional stages have a distinctive ability to spread clonally and have a growth form with more or less widely spaced ramets: Achillea moschata. Cerastium pedunculatum. Epilobium fleischeri and Hieraium staticifolium. The growth strategy and demography of the clonal E. fleischeri is presented as an example. The life cycle of this species is characterized in succession by (1) the colonization of safe sites by small seeds adapted for wind dispersal, (2) horizontal spread by clonal growth, and (3) the persistence through phenotypic morphological plasticity in later successional stages. Seedling establishment and clonal growth are thus complementary mechanisms in plant succession on recently deglaciated terrain.  相似文献   

3.
Germination rate and total germination of Epilobium hirsutumseed were increased by treatment with ethene in air (4 volumesper million) but seeds of Chamerion angustifolium were unaffected.Seventeen days from sowing the elongation of primary roots hadbeen reduced by ethene in both species but more markedly inE. hirsutum. Adventitious root formation at the base of hypocotylswas initiated by ethene in E. hirsutum but not in C. angustifolium.Root hair length was reduced by ethene rather more in E. hirsutumthan in C. angustifolium. The results are discussed in relationto the ecology and known differential waterlogging sensitivityof the two species. Epilobium hirsutum, Chamerion angustifolium, Willowherbs, ethene, germination, waterlogging, growth, roots, adventitious, ecology  相似文献   

4.
甘肃省鱼类资源现状及DNA条形码在鱼类物种鉴定中的应用   总被引:2,自引:0,他引:2  
为了摸清甘肃省土著鱼类资源与分布现状, 探索DNA条形码在鱼类辅助物种鉴定中的适用性, 2012年6-9月对甘肃境内黄河水系、嘉陵江水系和河西内陆河水系进行了较全面的鱼类调查。共采集鱼类标本3,087尾, 隶属于5目10科38属64种, 以鲤科种类最多, 为30种, 占总种数的46.88%。物种多样性分析表明, 在黄河水系的夏河和庄浪河多样性指数是所有调查点中最低的, 分别为1.38和1.09。嘉陵江水系各河段的多样性指数较高(H = 2.15-3.27), 其次为河西内陆河水系(H = 2.01-2.83)。在河西内陆河水系中, 疏勒河的均匀度指数最高, 为1.10, 黑河最低(0.68)。庄浪河的优势度指数最高, 为0.34, 而嘉陵江干流两当段的优势度指数在所有调查点中最低, 为0.04。利用DNA条形码分析了49种662尾标本的COI基因部分序列, 大部分种类在neighbor-joining系统树中形成各自的单系, 种内平均遗传距离0.88%, 种间平均遗传距离为9.99%, 在种内和种间COI序列遗传距离之间形成明显的条形码间隙, 斯氏高原鳅(Triplophysa stoliczkae)与达里湖高原鳅(T. dalaica), 甘肃高原鳅(T. robusta)与似鲇高原鳅(T. siluroides), 嘉陵裸裂尻鱼(Schizopygopsis kialingensis)与黄河裸裂尻鱼(S. pylzovi)之间的遗传距离低于2%, 甘肃高原鳅与似鲇高原鳅不能通过COI基因片段区分开, 其他两对物种可以采用核苷酸诊断法来进一步区分。斯氏高原鳅和拉氏鱼岁(Phoxinus lagowskii)种内遗传分歧较大, 揭示种内可能存在隐存种。结果表明, 对某些近缘种和不同地理种群差异较大的物种, 要将分子、形态和地理分布特点结合起来才能准确鉴定。  相似文献   

5.
Allelopathic plants are important resources for the discovery of bioherbicides. Rosebay willowherb [Chamaenerion angustifolium (L.) Scop. syn. Epilobium angustifolium L.] widely distributes in Western Asia, Europe, and North America, and behaves as a dominant species within the community due to the production of substances that restrict growth of other plants. This study aims at investigating the allelopathic potential of rosebay willowherb by evaluation of the effects of aqueous extracts from different parts on seed germination and seedling growth in lettuce (Lactuca sativa L.), as well as measuring the accumulation of reactive oxygen species and structural analysis of root tips via scanning electron and transmission electron microscopy. It was observed that the aqueous extracts from the leaves of rosebay willowherb had the strongest inhibitory effect on the germination index, germination energy and total germination of lettuce seeds, followed by capsular fruits and flowers, and the inhibition effect of stems was the weakest. All aqueous extracts (100 mg/mL) showed a significant inhibitory effect on radicle elongation of lettuce seedlings. Additionally, after treatment with the aqueous extract of rosebay willowherb leaves, accumulation of reactive oxygen species increased in columella cells, which correlated with disruption of root tip structure.  相似文献   

6.
Chemical analysis by high-performance liquid chromatography or capillary electrophoresis of plant pulverized samples, juices or extracts is an excellent method for the authentication of medicinal plant species and their products, particularly when morphological authentication is not possible. In the conventional procedure, chromatograms are integrated and the heights or areas of several peaks are used in a supervised pattern recognition method to confirm the authenticity of the product. We propose a new section approach in analysing chromatograms, where chromatograms are split into sections, which are described by four variables (number of peaks in the section, average retention time of peaks in the section, total area of peaks in the section and average area of peaks in the section), and these variables are then used in statistical analysis. The method is especially useful when the peaks on the chromatogram are not well separated and it is not easy to link individual peaks on one chromatogram with corresponding peaks on other chromatograms. In comparison with the standard procedure, our approach in analyzing chromatographic data of willow-herb (Epilobium and Chamaenerion spp.) extracts was more objective, gave better results and was also easier to perform.  相似文献   

7.
元谋干热河谷不同人工林中鞘翅目甲虫多样性比较   总被引:9,自引:0,他引:9  
在元谋干热河谷采用网扫法调查了云南松林、桉树林、新银合欢林、桉树+新银合欢林、印楝林及多树种混交的人工林鞘翅目昆虫多样性。结果表明,鞘翅目甲虫标本925号,计71种,分属18个科,其中叶甲科种类最丰富,象甲科数量最丰富。人工林鞘翅目昆虫群落物种丰富度在7~23,Shannon—Wiener多样性指数在1.249~2.562,昆虫多样性总体较低。各样地鞘翅目群落之间为不相似水平。云南松林鞘翅目昆虫群落物种丰富度、Shannon—Wiener指数、Simpson指数及Pielou指数分别为20、2.562、0.104和0.855,其多样性最高,多树种混交林较高,印楝林较低,而桉树林、新银合欢林、桉树+新银合欢林多样性极低。多树种混交的恢复对昆虫多样性提高有显著促进作用。  相似文献   

8.
A general method for obtaining species-specific repetitive DNA sequences is described. The method is based on the detection of recombinant DNA clones containing repetitive sequences using labeled total genomic DNA. These repetitive DNA sequences can be used to identify individual mosquito adults, pupae, and larvae squashed on filter membranes (squash blots). This technique was used to distinguish individuals of the four sibling species of the Anopheles quadrimaculatus complex. Repetitive DNA sequences and squash blots can be of use for rapid identification of other insect species in field collections.  相似文献   

9.
太湖鱼类群落结构及多样性   总被引:13,自引:0,他引:13  
为了解太湖鱼类群落结构和多样性的分布特征,于2009-2010年利用拖网等网具对该水域的鱼类资源进行了调查.结果表明:本次调查共采获鱼类50种,隶属10目15科40属,其中鲤形目种类最多,占总数的68%;鱼类生态类型以湖泊定居性种类为主,群落优势种为湖鲚(Coilia ectenes taihuensis)、间下鱵(Hyporhamphus intermedius)和陈氏短吻银鱼(Salangichthys jordani)等小型鱼类;与历史资料相比,太湖鱼类的物种数量下降,优势种组成发生较大变化,鱼类群落中体质量<30 g的小型鱼类占绝对优势,渔业资源小型化趋势明显.由于过度捕捞和湖泊环境恶化,鱼类群落生物多样性指数均表现偏低,物种丰富度指数D为1.54,多样性指数H’N、H’w分别为0.21和0.46,均匀度指数J'N、.J'w分别为0.07和0.14;太湖各湖区间鱼类种群和多样性的差别一定程度上反映出鱼类群落结构与湖泊营养盐、透明度等环境特征相适应的特点.  相似文献   

10.
The paper gives an account of the results of karyological investigation of 15 species from Czechoslovakia:Allium ochroleucum, A. senescens subsp.montanum, A. strictum, Asperula tinctoria, Aster amellus, Calamintha officinalis, Calystegia pulchra C. epium, Epilobium adenocaulon, Erysimum odoratum, Festuca pallens, Gasparrinia peucedanoides, Genista germanica, Gentiana pannonica, Glyceria nemoralis. Comments on taxonomic, nomenclatural and chorological problems are given for most of these species.  相似文献   

11.
A long‐term rainforest restoration experiment was established on abandoned pasture in northeastern Queensland in 1993 to examine the effectiveness of five different restoration planting methods: (T1) control (no plantings); (T2) pioneer monoculture (planting seedlings of one pioneer species, Homalanthus novoguineensis, Euphorbiaceae); (T3) Homalanthus group framework method (H. novoguineensis and eight other pioneer species); (T4) Alphitonia group framework method (Alphitonia petriei, Rhamnaceae, with eight other pioneer species); and (T5) maximum diversity method (planting pioneers, middle‐phase species, and mature‐phase species). We investigated temporal patterns in the (1) fate of seedlings originally planted in 1993; (2) natural recruitment of native plant species; and (3) current habitat structure (canopy cover and ground cover of grasses and invasive plants) within each restoration treatment. A total of 97% of seedlings planted in T2 died within the first 13 years and all had died by 2014. A total of 72% of seedlings planted in T3, 55.5% of seedlings planted in T4, and 55% of seedlings planted in T5 also died by 2014. By 2014, 42 species from 21 families had recruited across the experimental site, and the abundance of recruits was almost twice that recorded in 2001 and 2006. Overall, T3, T4, and T5 had the greatest diversity and abundance of recruits. By 2014, canopy cover was greatest in T3, T4, and T5 but grass cover was least in T5. It is concluded that some restoration success measures increase with planting diversity, but overall the rate of recovery is similar in framework species and maximum diversity method.  相似文献   

12.
为了探讨绿化植物生活型构成对边坡植被物种多样性及护坡性能的影响, 揭示生活型构成-群落特征-物种多样性-生态系统功能间的内在联系, 借助三物种组装实验, 分别构建以草本、灌木或乔木为主体的草本型(HHXi)、灌木型(SSXi)、乔木型(AAXi)或草-灌-乔混合型(HSA)配置模式的实验小区, 对实验区内边坡植被的群落特征、护坡性能进行持续4年的生态监测。结果表明: (1)边坡植被的物种丰富度与绿化植物生活型构成有关, AAXi的物种丰富度总体高于其他模式, 呈AAXi > SSXi > HSA > HHXi趋势。(2)不同配置模式边坡植被的群落盖度不一样, 年际间差异显著: 建坪初期(2010-2011年), HHXi的群落盖度远高于其他模式, HSA次之, AAXi最低; 2012-2013年间, HSA的群落盖度最高, HHXi次之, AAXi最低。(3)边坡植被的Shannon-Wiener指数、Pielou指数与绿化植物生活型构成有关, 其变化规律与群落盖度类似: 建坪初期, HHXi的多样性水平远高于其他模式, 呈HHXi > HSA > SSXi > AAXi趋势; 之后, 呈HSA > HHXi > SSXi > AAXi趋势。(4)边坡植被的护坡性能与群落内的物种多样性密切相关: 多样性水平越高, 护坡性能越强。可见, 在生态护坡过程中, 绿化植物生活型构成对提高边坡植被物种多样性、改善护坡性能至关重要。  相似文献   

13.
黄海山东海域春、秋季鱼类群落多样性   总被引:4,自引:0,他引:4  
根据2006年春季(5月)和秋季(10月)黄海山东海域疏目变水层双拖网调查数据,作者对该海域鱼类群落多样性、空间分布及长度谱特征进行了研究。调查共捕获鱼类61种,其中鲈形目种类最多(27种),其次为鲱形目(8种)和鲉形目(7种);按摄食类型可分为浮游动物食性、浮游动物/底栖动物食性、底栖动物食性、底栖动物/游泳动物食性、游泳动物食性、杂食性、碎屑食性7个类群,其中浮游动物食性占渔获物重量组成的82.5%。春、秋季鱼类群落均主要由小型种类占优势,春季优势种有3种,为玉筋鱼(Ammodytes personatus)、鳀(Engraulis japonicus)和方氏锦鳚(Pholis fangi),秋季优势种有5种,分别是鳀、青鳞小沙丁鱼(Sardinella zunasi)、玉筋鱼、小黄鱼(Larimichthys polyactis)和赤鼻棱鳀(Thryssa kammalensis)。丰富度指数(D)、Shannon-Wiener多样性指数(H’)、均匀度指数(J’)的空间异质性明显,表现出近岸海域(尤其是青岛-乳山南部近岸海域)较高,深水区较低的态势,但多样性指数的季节间差异不显著。资源量与Shannon-Wiener多样性指数(H’)、均匀度指数(J’)、功能团多样性指数(FD)均呈负相关关系,与种类丰富度指数(D)则无相关关系。春、秋季鱼类群落长度谱曲线斜率均小于-0.2,而截距均大于10,与该海域1985年及2000年的研究结果相比,长度谱斜率显著降低、截距显著增加,这与小型个体种类占优势密切相关。与历史资料相比,黄海山东海域鱼类群落多样性下降,小型个体比例上升,资源呈衰退趋势。  相似文献   

14.
本研究采用垂直面取样法,对中国长白山北坡不同海拔及干扰程度下访花食蚜蝇群落的物种组成、多度、丰富度及多样性进行了调查研究。我们选择了不同垂直带的两个样地,分别位于800~1 100 m和1 750 ~2 150 m;每个样地选取3种生境类型,每一生境类型采样面积为20 m×20 m。252组调查数据表明,共采到访花食蚜蝇42种2 540个体。不同海拔生境访花食蚜蝇的组成、多度、丰富度及多样性的差异分析结果表明: 低海拔样地内不同生境访花食蚜蝇的群落相似性高于高海拔样地;低海拔样地访花食蚜蝇的多度高于高海拔样地,而物种丰富度低于高海拔样地;不同生境类型访花食蚜蝇多样性指数存在差异,但高海拔样地与低海拔样地多样性差异不显著;过渡林生境(岳桦林带)与次生林生境(针阔混交林带Ⅱ)中访花食蚜蝇的多样性较高。保护珍稀植物物种的人工植物花园访花食蚜蝇多样性仅次于过渡林生境(岳桦林带)与次生林生境(针阔混交林带Ⅱ),保护作用显著。  相似文献   

15.
南亚热带森林群落种-多度的对数正态分布模型研究   总被引:6,自引:0,他引:6  
殷祚云  廖文波   《广西植物》1999,19(3):221-224
通过对地处南亚热带的广东省黑石顶自然保护区森林群落的定点研究结果的分析表明:当用1,2,3,…分组每种个体数r时,5个不同类型的群落样地的种一多度分布的直方图都呈明显的倒J-形;经Preston“倍程(octaves)”法分组r后,其种-多度都服从对数正态分布。由种-多度模型可以推出另一新的模型一个体一多度分布模型,即I(R)=2R0SOEXP[[1n2)2/4a2〕EXP{-a2(R-(RO+1n2/2a2)]2},它也符合对数正态分布。另外,还运用积分方法推导出估计总体(整个群落)中总种数S*和总个体数I*理论值的公式,用此公式估计的结果较为合理。  相似文献   

16.
根据2004—2005年大亚湾海域底拖网鱼类调查数据,并结合1980—2007年的历史资料,分析了该海域鱼类的种类组成、区系特征、多样性、优势种和数量变化趋势.结果表明: 2004—2005年,大亚湾海域共记录鱼类107种,分属13目50科,以中下层鱼类的种类最多,为48种,其次是中上层和底层种类,分别为37种和21种.大亚湾鱼类区系具热带和亚热带特性,以暖水性种类占绝对优势,为97种,暖温性种类为10种.多样性指数以夏季最高(3.82),其次是冬季(3.37)和秋季(3.00),春季最低(2.40).Pielou均匀度指数的季节变化情况与多样性指数相似.1980—2007年大亚湾海域鱼类群落特征发生了明显的变化:鱼类种类数减少,优势种更替明显.鱼类种类数由1980年的157种减少至1990年的110种,2004—2005年继续减少至107种;鱼类优势种由1980年以带鱼和银鲳等优质鱼为主,更替为以小型和低值的小沙丁鱼、小公鱼和二长棘鲷幼鱼为主.用包含年际变化趋势和季节性周期变化的回归模型模拟1980—2007大亚湾鱼类资源密度的变化,鱼类资源密度在1980—1999年和1990—2007年两个时期均呈下降趋势,但1990—2007年间下降幅度比1980—1999年间大;1980—1999年鱼类资源密度的季节波动幅度较平缓(振幅为0.099),而1990—2007年的季节波动较大(振幅为0.420),说明1990—2007年阶段大亚湾鱼类数量的季节变化更为显著.  相似文献   

17.
设置4个营养水平(I: 0.5 mg N·L-1, 0.1 mg P·L-1; II: 1.5 mg N·L-1, 0.3 mg P·L-1; III: 4.5 mg N·L-1, 0.9 mg P·L-1; Ⅳ: 13.5 mg N·L-1, 2.7 mg P·L-1), 研究了水体营养水平、物种组合及其交互作用对入侵漂浮植物凤眼莲、本地扎根浮叶植物黄花水龙和沉水植物苦草生物量累积与分配的影响.结果表明:随营养水平的升高,4个营养水平的凤眼莲和黄花水龙单种和混种的总生物量及茎叶生物量都呈上升趋势,凤眼莲和黄花水龙的总生物量在Ⅲ、Ⅳ处理下平均比Ⅰ、Ⅱ处理下分别增加了54.47%和102.63%;不同植物组合下,苦草各部分生物量呈下降趋势,Ⅲ、Ⅳ处理的总生物量比Ⅰ、Ⅱ处理平均降低了45.88%;经双因素分析,水体营养水平对凤眼莲和黄花水龙生物量有极显著的正影响(P<0.01),对苦草生物量有极显著的负影响(P<0.01);而植物组合的影响随目标植物的不 同呈现出差异.  相似文献   

18.
2001年11月至2002年8月在泉州湾浮山(R1)、下洋(R2)、垵头(R3)和大坠岛(R4) 选择4条岩相潮间带断面对底栖生物分布进行了调查,共采集了6687号标本.经分析鉴定共有324种,其中有藻类17种,多毛类102种,软体动物96种,节肢动物62种,棘皮动物11种,其他动物共有36种.岩相断面种类的水平分布受制于潮流和海浪,不同断面的种数排序是浮山(206种)>下洋(197种)>大坠岛(193种)>垵头(166种).垂直分布主要受制于潮汐和海浪.各断面不同潮区的共同特征是中潮区的物种最多,在129-156种之间;低潮区居第二,在87-116种之间;高潮区的种类最少,在9-20种之间.种数的季节变化反映生物对水温的适应性,不同季节种数排序为夏季(190种)>春季(164种)>秋季(158种)>冬季(150种).  相似文献   

19.
中国鮡属鱼类二新种记述(鲇形目:鮡科)   总被引:1,自引:0,他引:1  
本文报道在四川西部收集的鮡科鱼类标本中,发现有鮡属(Pareuchiloglanis)的壮体鮡,新种P.robusta sp.nov.和四川鮡,新种P.sichuanensis sp.nov.,对二新种的形态特征作了详细描述,并与相近种的主要性状列表进行比较。  相似文献   

20.
采用典型调查与路线调查相结合的方法,对贵州乌江东风水库库区消落带苔藓植物区系的物种组成、生活型、分布区类型和丰富性进行了调查和分析.结果表明:该区域共有苔藓植物18科58属101种,其中,藓类植物有16科56属99种,苔类植物有2科2属2种;优势科为灰藓科(Hypnaceae)、青藓科(Brachytheciaceae)和丛藓科(Pottiaceae),优势属为青藓属(Brahchythecium B.S.G.)、真藓属(Bryum Hedw.)和小曲尾藓属〔Dicranella(Müll.Hal.)Schimp.〕;单属科和单种属所占比例均较高,分别占该区域苔藓植物总科数和总属数的500%和638%.该区域分布的苔藓植物生活型可分为交织型、丛集型、垫状和平铺型4类,以丛集型种数最多(48种),占该区域苔藓植物总种数的475%.该区域分布的苔藓植物可划分为12个分布区类型,其中,温带成分种类最多,所占比例为815%;热带成分所占比例仅为185%;中国特有种所占比例也较高,为207%.该区域苔藓植物的丰富性综合系数(Si)为-03608,低于相邻的六冲河下游流域.综合分析结果表明:该区域的苔藓植物多样性较为丰富,多数种类具有较强的抗逆性,且丛集型苔藓种类最多,与库区消落带的特殊生境相适应;地理成分以东亚成分和北温带成分为主,总体属温带性质,且中国特有种较多,反映出该区域苔藓植物区系的特殊性和复杂性.  相似文献   

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