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1.
藓纲植物化学成分及其生物活性研究进展   总被引:6,自引:0,他引:6  
藓纲植物是天然活性产物的重要来源,在自然界分布广泛;但是对藓纲植物的化学成分及其生理活性的研究较少,国内基本属于空白。本文对近年来该领域内的研究成果进行了综述,旨在引起化学家、植物学家及其他相关科学家对此门类研究的兴趣和重视,共同开发这一重要资源。  相似文献   

2.
暖地大叶藓化学成分的研究   总被引:1,自引:0,他引:1  
从真藓科大叶藓属植物暖地大叶藓Rhodobryum giganteum(schwaegr.)Par.的乙醇提取物中分离得到9个化合物,通过波谱分析鉴定其分别为麦角甾-7,22-双烯-3β,5α,6β-三醇(1),乌苏酸(2),琥珀酸(3),尿嘧啶(4),棕榈酸(5),槲皮素(6),碳二十九烷(7),β-谷甾醇(8),胡萝卜苷(9).化合物1~9均为首次从该植物中分离得到.  相似文献   

3.
    
Chlor-alkali plants are known to be major sources of Hg emissions into the air. Therefore level of this metal in their surrounding must be carefully controlled. The aim of this work was to study the impact of the chlor-alkali industry in Brzeg Dolny (SW Poland) on the length of the vegetative short shoots of the pollution tolerant Betula pendula using the concentrations of Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb and Zn in the ubiquitous, terrestrial moss Brachythecium rutabulum as the pollution indicator of the environment. This investigation showed up to 14 mg kg−1 elevated concentrations of Hg in mosses from sites the most close (0–500 m) to the chlor-alkali factory. This concentration decreased with increasing distance from the factory. Two and half km away from the factory the Hg concentration falls to values of 0.1–0.2 mg kg−1 being still higher than background concentrations of 0.03–0.04 mg kg−1. Decreasing concentrations of Co, Cr, Fe and Ni were also correlated with increasing distance from the plant. The results indicate that B. rutabulum may be a suitable ecological indicator of metal pollution by chlor-alkali industry. Higher concentration of accumulated metals by this moss corresponds with longer vegetative short shoots of B. pendula. Vegetative short shoots may be used as bioindicators of metal pollution where mosses are absent. This study demonstrates the importance of controlling the emissions of chlor-alkali industry especially if situated in the midst of densely populated areas with potential risks to the inhabitants.  相似文献   

4.
综述了切尔诺贝利核事故以来乌克兰Schmalhausen动物研究所(SIZ)对核工厂周围隔离区(exclusionzone ,EZ)的野生动物所进行的长达20年的放射生态学调查研究。基于乌克兰以往鸟类迁移的观察资料,评估了137Cs和 90Sr在隔离区候鸟体内的含量。而且还选择一些动物物种作为环境状况的标准指示生物,目的是为了阐明1 37Cs在隔离区脊椎动物体内的污染情况;整个第聂伯河流域、基辅行政区和隔离区软体动物贝壳内 90Sr的β活性。结果表明不同物种相对放射性核累积、迁移和累积因素呈有规律的季节性和长期性变化趋势,这些参数的运用可以大大地减少数据的波动和复杂性。直接辐射毁坏森林后,营养链的崩溃和病死树昆虫害虫的爆发导致了其次级生态变化。99 %的隔离区并不直接受辐射的影响,人员撤离、农业和森林管理停止以及大规模排除污染是这些区域生态变化的主要因素。在初始变化之后,由于自然资源、捕食者和偷猎者等的限制,隔离区的动物密度和分布达到一个稳定的极限值。数年前成功地在隔离区引入了一群蒙古野马,该群体保持了稳定增长。重新评估了以前划定的若干自然保护位点目前的保护状况,并提出了建议扩大这些自然保护区的范围等保护措施。  相似文献   

5.
6.
    
The moss vegetation of the Windmill Islands can be classified into the following seven communities: 1.Grimmia antarctici community; 2. G. antarctici-Ceratodon purpureus community; 3. Bryum pseudotriquetrum community; 4. G. antarctici-B, pseudotriquetrum community; 5. Ceratodon purpureus community; 6. C. purpureus-G, antarctici community; 7. C. purpureus B. pseudotriquetrum community. Communities 1, 3, 4 and 7 occur in wet habitats while communities 5 and 6 are found in rather dry habitats, community 2 distributes between dry and wet habitats. Microtopography governs the distribution of water supply and therefore community types. Stable moss communities usually form moss hummocks and hollows. Species composition, colour and height of the hummocks determines the vertical structure of the moss community layers with 2-3 strata being discernible and level structure forming mosaic. Other phytocoenological characteristics of the moss communities, such as the dense moss cushions, asexual reproduction (although antheridia or archegonia have been found in each of the species), abundance of epiphytic algae and lichens growing on the surface of moss hummocks, the colour change of some species in different habitats, appear related to moisture availability, light intensity, wind exposure and temperature.  相似文献   

7.
Species diversity of vascular epiphyte plant communities was studied in La Carbonera, a montane rain forest dominated by Podocarpaceae in the Venezuelan Andes. We compared the epiphyte communities of the primary, disturbed, and secondary forest areas of La Carbonera in order to augment the scarce knowledge on the effects of anthropogenic disturbance on these important elements of tropical vegetation. Diversity of vascular epiphytes (191 species in the whole forest area) was low in the disturbed and secondary areas (81 spp.) compared to adjacent primary forest (178 spp.). Four types of disturbed forest and secondary vegetation supported different numbers of epiphyte species, showing a decline with increasing degrees of disturbance (65 spp. along a road transect, 42 spp. on relict trees in disturbed forest, 13 spp. in a tree plantation and 7 spp. in a former clearing, both secondary vegetation units). Epiphytic species composition in primary and disturbed or secondary forest areas differed markedly: disturbed habitats harboured fewer fern and orchid species but more bromeliad species than the primary forest. Probably the families occurring only in primary forest sites of our study may be useful as bioindicators to determine the degree of disturbance in other habitats of mountain rain forests as well. Epiphyte abundance was also lower in disturbed habitats: a remnant emergent tree supported only about half as many epiphyte individuals as a member of the same species of similar size in the primary forest. The decrease in species numbers and abundance as well as the differences in species composition are mainly due to the less diverse phorophyte structure and less differentiated microclimate in the disturbed and secondary vegetation compared to the primary forest.  相似文献   

8.
Dried mosses (five moss species) were progressively extracted and subjected to a four-step Craig distribution. Seven pure flavonoids were isolated and identified. The flavonoids were the flavones apigenin, apigenin-7-O-triglycoside, lucenin-2, luteolin-7-O-neohesperidoside, saponarine and vitexin; and the biflavonoid bartramiaflavone and they were submitted to biological tests. The tests were performed in vitro on spore germination and protonemal growth of the moss Tortula muralis and on seed germination and root growth of Raphanus sativus. Flavonoids caused a decrease in the percentage of spore germination, protonemal development and root growth. In addition they caused morphological alterations, such as forked tips, swollen apices, rounded cells and early formation of brood cells in the protonemata. Data were discussed in relation to the presence of allelochemicals in mosses.  相似文献   

9.
Diatom floras from springs have received little attention until recently, despite the fact that springs provide specific conditions that cannot be found in any other aquatic system, and remain of great importance in terms of general environmental changes. Due to pollution of the Kraków-Częstochowska upland aquifers, the chemical composition of spring waters in the area is anthropogenically modified, and far from the natural state. In order to generate a baseline diatom flora for springs, a paleolimnological study was applied as one of the best recognized and applied methods used to track long-term environmental changes worldwide. Little is known, however, about the direction and nature of such changes in aquatic environments fed by springs. The present article focuses on shifts in diatom assemblages preserved in sediments collected from a small pond, situated close to several spring outlets. They were interpreted as a record of environmental changes that had taken place during the last century. For most of the history of the pond—as recorded in this 84 cm long core—the diatom assemblage was dominated by small Fragilaria spp. The major shifts in species composition began in a core depth of 65 cm with a decline in Fragilaria construens var. venter (Ehrenberg) Grunow and Fragilaria pinnata Ehrenberg complexes, and a concurrent increase in Achnanthidium minutissimum (Kützing) Czarnecki. The second change was recorded at the depth of 45 cm with a sharp decline of A. minutissimum, which again was replaced by the small Fragilaria spp. In recent years, further changes in the diatom assemblage occurred, with a notable increase in Cyclotella delicatula Hustedt. The assemblage shifts recorded at this site appear to be consistent with environmental changes triggered by land use (e.g. agriculture intensity) and/or possible changes in spring water discharge. Guest editors: K. Buczkó, J. Korponai, J. Padisák & S. W. Starratt Palaeolimnological Proxies as Tools of Environmental Reconstruction in Fresh Water  相似文献   

10.
    
Although Carabidae is among the best-studied families of beetles in Europe from the faunistic point of view, there is still a lack of available information on the ecological requirements of the particular carabid species. The habitat preferences that determine the distribution of species are largely influenced by habitat structure and microclimate. In addition to other factors, these habitat parameters are influenced by the nature of the vegetation. Therefore, our study investigated the influence of tree species on carabid beetle communities. We conducted the research at 9 stands in the Borová Hora Arboretum (Zvolen, Central Slovakia). Each studied site represents a monoculture of one of nine tree species. At each site, some soil and leaf litter attributes (pH, conductivity, and content of H, C, N and P) were evaluated. Ground beetles were collected by pitfall trapping during the vegetation periods in 2008–2011. In total, 3012 individuals of 29 species were obtained. Significant differences in the total dynamic activity and species richness of the carabid beetle communities among the compared forest stands were revealed. The results of the research confirmed statistically significant relationships among 1) the soil conductivity and both the richness and Shannon diversity of the ground beetle communities, 2) the litter and soil N content and richness, the Shannon diversity and the species composition of the ground beetle communities. The Shannon diversity and richness were negatively related to the soil conductivity and positively related with the N content. Our research showed that dominant tree species indirectly influence diversity and composition of carabid communities via the soil properties.  相似文献   

11.
    
Water quality in lowland lentic system was evaluated through the use of aquatic macroinvertebrates as bioindicators, and their relationship with basic physicochemical factors was considered; thus, two biotopes were established for identifying both groups of macroinvertebrates, one being the population associated with macrophytes (AM) and the other being benthic (B). As a result, 46 families of macroinvertebrates were collected, with Hydrobiidae, Chironomidae, Thiaridae and Polymitarcyidae being the most abundant in the system. In addition, families with high tolerance to extreme conditions, such as Ceratopogonidae, Chironomidae and Syrphidae, were found, as well as some families with low tolerance to these conditions, such as Caenidae and Leptoceridae. The first biotope presented 7.189 individuals (50.42%) and the second 7.056 (49.5%), for a total of 14.259 individuals. Biotope AM presented 100% of the richness, while biotope B was significantly less rich, with 15 families, which represent 32,06%. In order to evaluate the families found in the lowland lentic system, their distribution in the ranges of variation of the physicochemical factors and tolerance levels was taken into account. As a consequence, a new score table was established, where this system obtained a total score of 207 with an average of 166 per sampling station, suggesting signs of contamination. Finally, these results allow an adaptation of the BMWP (Biological Monitoring Working Party) index to be proposed, including the lowland lentic systems.  相似文献   

12.
    
Damage to terrestrial ecosystems from long-term atmospheric nitrogen pollution is a key conservation challenge in many industrialized countries. An important research and management priority is the identification of bioindicators to allow pollution exposure and ecological impacts to be determined at an individual site. We evaluate the impacts of nitrogen (N) deposition and identify methods with bioindication potential across a national-scale pollutant deposition gradient for British heather moorlands. Nitrogen deposition is associated with distinct changes in plant community structure, including reduced bryophyte and vascular plant species richness, and changes in the frequency of many species. Notable results include positive correlation with nitrogen for the invasive bryophyte Campylopus introflexus and negative correlation for the pollution-sensitive Hylocomium splendens and Pleurozium schreberi. Higher nitrogen deposition is associated with increased plant foliar N in a dwarf shrub and a bryophyte, increased extractable litter N, and reduced activity of the enzyme phenol oxidase. Although gradient study results cannot prove causation it is clear that Nitrogen deposition exerts a widespread impact on the ecology and biogeochemistry of heather moorlands. Bioindicators can be used to evaluate exposure and impacts, a promising approach could combine plant species richness and litter nitrogen analyses.  相似文献   

13.
    
《Journal of bryology》2013,35(4):276-283
  相似文献   

14.
安徽与邻近省藓类植物区系数量统计比较   总被引:1,自引:0,他引:1  
区系中的物种丰富度是衡量该区域中植物群落的环境条件、群落结构以及群落发育程度等的重要指标,利用丰富度指数公式,通过对安徽省与其相邻的六个省的藓类植物进行比较,可以看出安徽省藓类植物的物种多样性位居第三,是较为丰富的地区之一;在七省中安徽藓类植物属的系数最低,说明安徽藓类植物区系的丰富度和生境条件的复杂程度是较高的;比较七省的藓类植物丰富度指数与自然地理条件的关系,可认为纬度、降水量、温度以及丘陵山地占该地区总面积的百分比等地理条件综合作用影响藓类植物分布的丰富程度。  相似文献   

15.
Large-scale restoration of streams and rivers is a mandatory prerequisite for the implementation of the European Water Framework Directive (WFD) to reach good ecological status of water bodies. This contribution analyzes the success of the largest river restoration in Germany at the Upper Main. Sections with a length of more than 18 km were restored between 1990 and 2008, including re-connection of former oxbow-lakes, multiple-channelling, and establishment of wide riparian buffer zones.Measuring the success of restoration by means of a multimetric assessment system, we found a clear success of restoration indicated by the status of hydromorphology and by the biological parameters, including macroinvertebrates, fishes, and macrophytes. Unlike non-restored reaches, the restored reaches attained a good ecological status. As such, the restoration of the Upper Main is shown to be a pilot project for the implementation of the WFD on a large scale.  相似文献   

16.
五种藓类植物的孢子萌发与原丝体发育   总被引:5,自引:0,他引:5  
衣艳君  强胜 《植物学通报》2005,22(6):708-714
本文对中华缩叶藓(Ptychomitrium sinense)、狭叶缩叶藓(P.linearifolium)、威氏缩叶藓(P.wilsonii)、葫芦藓(Funaria hygrometrica)和立碗藓(Physcomitrium sphaericum)5种国产藓类植物的孢子萌发和原丝体发育进行研究,结果表明不同藓类孢子萌发和原丝体发育类型不同,孢子萌发和原丝体发育方式与藓类植物的生态环境有关.  相似文献   

17.
黄山藓类植物区系   总被引:2,自引:0,他引:2  
对黄山进行了多次实地调查、考察和标本采集,经分类鉴定,收集整理有关黄山藓类的研究资料,目前黄山藓类植物有46科、135属、401种(包括7亚种和22变种),与20世纪50年代陈邦杰等以及后来对黄山的调查研究结果相比,藓类植物增加了4科、28属、184种;科内种数(≥15种)优势科有10个,属内种数(≥6种)的优势属有18个。黄山藓类植物地理成分类型复杂,东亚成分(包括中国特有)占37.82%,温带成分占35.13%,热带、亚热带成分占26.75%,表现出明显的由亚热带向温带过渡的特性。  相似文献   

18.
    
Acrocarpous mosses present on stonewalls in urban areas may be used for monitoring purposes. Therefore for this investigation we selected Tortula muralis expecting that this species with an ability to colonise buildings in polluted agglomerations where other species have vanished may provide important information to monitor environmental quality. Concentrations of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn in T. muralis, in dust deposited on sandstone surfaces, and in the sandstones on which the moss grew were measured. T. muralis appeared to be a good bioindicator of airborne pollution which accumulated especially extremely high Cu, Fe and Zn concentrations reaching values much higher than harmful for plants. There was no relation between metal concentrations in underlying sandstones and T. ruralis. There was a relation between metal concentrations in dust and T. muralis. Cd, Co, Cr, Mn and V concentrations in T. muralis were higher than in dust. The Self-Organizing Feature Map identifying groups of sampling sites with similar concentrations of metals in mosses was able to classify the pollution level by distinguishing groups of highly, medium and less polluted sites. Once trained, SOFM can be applied in ecological investigations and could form a future basis for recognizing e.g. the type of pollution in urban environments by analysing the concentrations of elements in T. muralis.  相似文献   

19.
The draining of mires for silvicultural purposes has caused one of the most dramatic changes in the landscape during the last century in Finland. To study the effects of mire drainage, carabid beetle assemblages were sampled using pitfall trapping in three different mire habitat types. Carabids were sampled from mires in their natural state, drained mires and drained mires with an open power line to see whether the cleared power line can serve as an alternative habitat for mire dependent carabids. The draining of mires greatly increases the species richness of the carabid assemblages. Yet, the conservation value of the environment has dropped following the draining, since only common and abundant forest carabids have benefited from human impact. The role of the open power line as an alternative habitat for mire specialists remains questionable. A few carabid species have, however, benefited from the open habitat of the power line. The vegetation structure had a significant effect in determining the compositions of the carabid assemblages on the studied habitat types. It seems that mire dwelling carabids cannot survive on the drained mires, unless at least some characteristics, other than the mere openness of the cleared power lines, of natural mires remain.  相似文献   

20.
上海市地面藓类植物的分布格局分析   总被引:8,自引:2,他引:8  
曹同  陈怡  于晶  宋国元 《应用生态学报》2004,15(10):1785-1791
在上海市选取20个公园和2个化工厂设立22个样点,对地面藓类植物进行野外样方调查、标本鉴定和数据统计.基于75种记录的藓类植物及其盖度数据,应用双向指示种分析法(TWINSPAN)和除趋势对应分析(DCA)分析其分布格局.结果表明,上海市地面藓类植物可聚类为3个样点组,样点组1为市中心2个公园和2个化工厂,共有藓类23种,总盖度最小(21.29%);样点组2为部分市中心公园和外围公园,共有藓类44种,总盖度37.94%;样点组3主要为外围公园和市郊公园,共有藓类49种,总盖度为49.66%.结果反映了藓类植物分布与不同生境,环境污染及人为干扰有一定相关性.  相似文献   

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