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1.
The chorology and ecology of Sisymbrium volgense Bieb. ex E. Fourn. in Czechoslovakia is reviewed. There are also brief data on the history of the spread and ecology in other countries. A list of localities in Czechoslovakia and a distribution map is provided.  相似文献   

2.
The occurrence of beet mild yellowing virus (BMYV) on feeding- and sugar-beet in Czechoslovakia has been proved. The virus was transmitted by aphidMyzus persicae (Sulz.) on indicator plantsSinapis alba L.,Capsella bursa-pastoris Medik, andClaytonia perfoliata Donn and from these plants back to sugar-beet cv. ‘Dobrovická A.’ A weed plantRaphanus raphanistrum L. was identified as a new natural host plant of BMYV. The virus was identified in ten of twelve biologically examined samples of beet with BMYV-like symptoms, which were collected at various places in Czechoslovakia  相似文献   

3.
A new species (tetraploid with 2n=24) of the groupLuzula campestris-multiflora is described from Czechoslovakia. The species also occurs in Hungary and Germany.  相似文献   

4.
The first part of the study gives a survey and brief phytocenological evaluation of the grassland stands in the environs of the village Chvaletice and of the town P?elou? in the southeastern part of the Labe lowlands (central and eastern Bohemia, Czechoslovakia). On the basis of the relevé materials acquired in 1974, 18 associations with their subordinate units were characterized by means of the method of the Zürich-Montpellier school. For the first time a record is published of the associationHolcetum lanati Gams 1927 from Czechoslovakia. The following new syntaxa are described:Holcetum lanati cirsietosum cani, Holcetum lanati arrhenatheretosum elatioris, Cerastio arvensi-Festucetum trachyphyllae, Cerastio arvensi-Festucetum trachyphyllae trifolietosum pratensis, andCerastio arvensi-Festucetum trachyphyllae armerietosum elongatae.  相似文献   

5.
Twenty three species ofHyphomycetes new to Czechoslovakia are listed with comments and illustrations. Seven are new to science—Blastophorum pini, Bloxmia bohemica, Junctospora pulchra, Linodochium formosum, Phaeostalagmus peregrinus, Sporidesmium doliiforme, Xiambola mirabilis—and of these, two are the types of new genera (Junctospora andXiambola). The new species and genera are described, illustrated and discussed. Anamorphs ofMytilidion gemmigenum Fuckel andPseudohelotium pineti (Batsch exFr.)Fuckel inTaeniolella andLinodochium, respectively are reported. Collections of these fungi from Britain are also cited. Data on morphology, ecology and distribution of those species occurring in both Britain and Czechoslovakia are compared.  相似文献   

6.
Eight newRubus species are described from the area of Czech Republic (western Czechoslovakia), four of them belonging to ser.Discolores, and one by one to subsect.Rubus, ser.Rhamnifolii, ser.Micantes and ser.Hystrices. *** DIRECT SUPPORT *** AAY02002 00005  相似文献   

7.
A new genusBactrodesmiastrum Hol.-Jech. is established for a fungus of dematiaceous hyphomycetes collected on decaying wood ofFagus sylvatica in Czechoslovakia. The only species,B. obscurum Hol.-Jech. is described and illustrated.  相似文献   

8.
湘中丘陵区不同演替阶段森林土壤活性有机碳库特征   总被引:5,自引:0,他引:5  
孙伟军  方晰  项文化  张仕吉  李胜蓝 《生态学报》2013,33(24):7765-7773
为了解天然次生林保护对土壤活性有机碳库的影响,采用空间替代时间研究方法,对湘中丘陵区不同演替阶段4种林分类型(杉木人工林、马尾松+石栎针阔混交林、南酸枣落叶阔叶林、青冈+石栎常绿阔叶林)土壤活性有机碳及其与土壤养分相关性进行研究。结果表明:1)各土层总有机碳(TOC)、微生物生物量碳(MBC)、水溶性有机碳(DOC)、易氧化有机碳(EOC)含量均表现为:青冈+石栎常绿阔叶林 > 南酸枣落叶阔叶林 > 马尾松+石栎针阔混交林 > 杉木人工林,在0-30cm土层,马尾松+石栎针阔混交林、南酸枣落叶阔叶林、青冈+石栎常绿阔叶林TOC含量比杉木人工林分别高出13.40%、19.40%和29.91%,MBC含量分别高出15.62%、32.89%和53.33%,DOC含量分别高出8.52%、8.75%和13.76%,EOC含量分别高出32.79%、38.48%和78.30%;2)天然次生林各土层MBC占TOC的比率以南酸枣落叶阔叶林最高,青冈+石栎常绿阔叶林为其次,马尾松+石栎混交林最低,均高于同一土层杉木人工林(除马尾松+石栎混交林15-30cm土层外),天然次生林各土层DOC占TOC的比率随着演替进展而下降,均低于同一土层杉木人工林(除马尾松+石栎混交林0-15cm土层外),天然次生林各土层EOC占TOC的比率随着演替进展而增加,且均高于同一土层杉木人工林;3)土壤MBC、DOC、EOC含量与TOC含量的相关性均达到极显著水平,且天然次生林土壤MBC、DOC、EOC含量与TOC含量的相关系数随着演替进展而增高,均高于杉木人工林;4)4种林分土壤TOC、MBC、DOC、EOC含量与土壤全N、碱解N、全P、有效P、全K、速效K含量之间的相关性均达到显著或极显著水平。  相似文献   

9.
Paulschulzia pseudovolvox (Schulz)Skuja, a member of theTetrasporales, is recorded for the first time for Czechoslovakia.Amphidinium radiatum Javorn., a member of theGymnodiniales is recognized. Further information about its variability is supplemented. The algae were studied in two reservoirs.  相似文献   

10.
Epiphytic lichen biota on Picea abies and Pinus sylvestris in Estonia was studied. Twenty-one spruce and 21 pine sample plots were located in old forests with long forest continuity, and 12 spruce and 12 pine sample plots in young first-generation forests (<100 years). Altogether 103 lichen species were recorded on the 330 sampled trees. Lichen species richness per plot was significantly higher in old forests in case of both tree species; 31 lichen species, including red-listed and protected species, were found only in old forests. Tree age had a positive effect on lichen species richness on tree stem in old and young spruce forests and in young pine forests. Tree age also had an effect on the presence of several species. Both tree age and forest continuity affected lichen species composition. Arthonia leucopellaea, Chrysothrix spp. and Lecanactis abietina were found in at least every third old spruce or pine forest and in no young forests, and can be regarded as good indicators of old coniferous forests with long continuity in Estonia.  相似文献   

11.
Most studies on frugivorous bat assemblages in secondary forests have concentrated on differences among successional stages, and have disregarded the effect of forest management. Secondary forest management practices alter the vegetation structure and fruit availability, important factors associated with differences in frugivorous bat assemblage structure, and fruit consumption and can therefore modify forest succession. Our objective was to elucidate factors (forest structural variables and fruit availability) determining bat diversity, abundance, composition and species-specific abundance of bats in (i) secondary forests managed by Lacandon farmers dominated by Ochroma pyramidale, in (ii) secondary forests without management, and in (iii) mature rain forests in Chiapas, Southern Mexico. Frugivorous bat species diversity (Shannon H’) was similar between forest types. However, bat abundance was highest in rain forest and O. pyramidale forests. Bat species composition was different among forest types with more Carollia sowelli and Sturnira lilium captures in O. pyramidale forests. Overall, bat fruit consumption was dominated by early-successional shrubs, highest late-successional fruit consumption was found in rain forests and more bats consumed early-successional shrub fruits in O. pyramidale forests. Ochroma pyramidale forests presented a higher canopy openness, tree height, lower tree density and diversity of fruit than secondary forests. Tree density and canopy openness were negatively correlated with bat species diversity and bat abundance, but bat abundance increased with fruit abundance and tree height. Hence, secondary forest management alters forests’ structural characteristics and resource availability, and shapes the frugivorous bat community structure, and thereby the fruit consumption by bats.  相似文献   

12.
Up till now 22 plant associations of springs and mountain brooks are known in Czechoslovakia. They can be arranged in 6 alliances:Cardaminion amarae, Cardamino-Montion, Swertio-Anisothecion squarrosi, Cratoneuro filicini-Calthion laetae, Cratoneurion commutati andLycopo-Cratoneurion. Three alliances, two associations and one subassocíation are described as new ones, three associations are renamed.  相似文献   

13.
Why do fires occur more frequently in Pinus densiflora forests in Korea, and why is the related damage more severe on such sites? We assumed that the reasons stem from characteristics of the tree species, including their combustibility, morphology and stand structure. Investigating both P. densiflora forests and the less vulnerable Quercus variabilis forests along the Korean eastern coast, we determined that, in spring, when fires are most frequent, the extremely flammable moisture content of fine fuels (6%) is not significantly different between the two types and the fine fuel load is much greater in the Q. variabilis forests. The P. densiflora forests retain more ladder fuel due to the greater coverage and density of their shrub layers in addition to their dead branches from lower on their boles and thinner barks, which enable fires to spread vertically with greater tree withering. Thus, when one considers all of these factors in combination, the following conclusions become apparent. First, in the initial ignition phase of fire, P. densiflora forests are more vulnerable due to their combustion characteristics. Second, those forests might allow flames to move vertically because of tree morphology and a stand structure that retains abundant ladder fuel. Finally, P. densiflora forests might be vulnerable to massive blazes because of their vast contiguous nature, especially in that region of Korea.  相似文献   

14.
Forest dieback in Czechoslovakia   总被引:1,自引:0,他引:1  
The article reviews the literature dealing with levels of air pollution in Central Europe and Czechoslovakia particulary in connection with the rate of forest damage and dieback since the fifties. To date 57 percent of forests on an area of 15.000 square km are damaged in Czech republic and more than 40.000 ha of dead Norway spruce forest had to be cut out. Deforested hills are vegetated mostly by Calamagrostis villosa only. The reforestation faces many obstacles of which the change of mezoclimate, the acidification and intoxication of the soil, the disappearance of mycorrhizal fungi and pressure of consumers may be named.  相似文献   

15.
The montane forest in central Veracruz, Mexico is a hotspot of biodiversity. We asked whether lower and upper montane forests could be distinguished in this ecoregion. Variables of vegetation and seasonality in precipitation were tested across 14 sites between 1,250- and 2,550-m elevations. A total of 1,639 individuals and 128 tree species was recorded. There was a unimodal pattern in the richness of species, genera, and families; their richness was positively correlated with precipitation in the wettest quarter of the year, though there were no differences in the basal area and density. Rarefaction, species turnover, nonmetric multidimensional scaling, and a cluster histogram suggest two major groups: lower elevation forests that are less diverse, have low beta diversity and are more similar in composition, with Clethra macrophylla, Liquidambar styraciflua, and Quercus lancifolia as indicator species; and higher elevation forests that are more diverse, have high species turnover, and include forests with Quercus corrugata and Prunus rhamnoides, and forests with Fagus grandifolia, Persea americana, and Ternstroemia sylvatica as indicator species. However, other communities (an Oreomunnea mexicana at the upper site, and a limestone site in the lower forests), exemplify the high regional heterogeneity. We conclude that elevation and seasonality in precipitation produce a directional change in richness and indicator species, but not in vegetation structure. Lower montane forests differed from cloud forests at upper elevations. However, other factors should be included—mainly biogeographic affinities, historic and recent anthropogenic disturbance—to conclusively distinguish them. Montane forest can still be considered very heterogeneous and very high in beta diversity.  相似文献   

16.
The paper summarizes hitherto known data concerning the biology and ecology ofSagittaria sagittifolia. The distribution of this species in Czechoslovakia was assessed on the basis of literature data, herbarium specimens and the authors’ own data. The occurrence of this species in plant communities is shown in tables from selected phytocoenological relevés. The chemical properties of the substratum in habitats ofSagittaria sagittifolia over all its distribution area in Czechoslovakia were studied and comparisons calculated by means of cluster analysis. Life cycle, seed production, germination and biomass production of this species were studied and compared with conditions in its habitats.  相似文献   

17.
Ligustrum lucidum is the major exotic tree in NW Argentina montane forests (Yungas). To assess the effects of its expanding invasion on avian communities we (1) measured different habitat properties (vertical forest structure and composition, vegetation cover, light availability, air temperature, air relative humidity and soil litter depth), (2) compared bird species composition and diversity in Ligustrum-dominated and native-dominated secondary forests and (3) analyzed seasonal patterns and changes in these variables between forest types. The study was conducted during 2010–2011 wet and dry seasons, at two altitudinal zones: 500–800 and 1100–1450 masl. Compared with native forests, Ligustrum dominated forests had a more homogeneous vertical forest structure and denser canopy cover (resulting in lower understory solar radiation), significantly lower understory cover and lower litter depth. Air temperature and relative humidity did not differ between forests in either season. Solar radiation was higher in the dry season in both forest types, but litter depth showed opposite patterns between seasons depending on forest type. We recorded 59 bird species in 21 families. Bird species abundance, richness and diversity indexes were significantly lower in Ligustrum-dominated relative to native forests of similar successional age, which had almost twice as many species as the former. Avian communities differed between altitudinal zones, but the difference was stronger between Ligustrum and native-dominated forests. Avian community composition was less variable in time and space in native forests than in Ligustrum-dominated ones. Our results suggest that L. lucidum invasion generates structurally homogeneous and simpler forests that represent a less suitable habitat for a diverse avifauna. This illustrates the wide ecological changes (from habitat properties and ecosystem functioning to vertebrate community composition) that the subtropical mountain forests of Argentina are experiencing with this invasion.  相似文献   

18.
19.
Using the Braun-Blanquet approach, a syntaxonomical revision of the order ofQuercetalia pubescenti-petraeae, based on the synthesis of 634 relevés, distinguished three alliances of the thermophilous oak forests in the Czech Republic: (1)Quercion pubescenti-petraeae (3 communities:Pruno mahaleb-Quercetum pubescentis, Lathyro versicoloris-Quercetum pubescentis, Corno-Quercetum), which includes peri-alpine and peri-Carpathian oak forests on calcareous bedrock, (2)Aceri tatarici-Quercion (2 communities:Quercetum pubescenti-roboris, Carici fritschii-Quercetum roboris), which comprises Pontic-Pannonian oak forests on loess or sand that occur in southern Moravia only, (3)Quercion petraeae (5 communities:Potentillo albae-Quercetum, Brachypodium pinnatum-Quercus robur community,Sorbo torminalis-Quercetum, Genisto pilosae-Quercetum petraeae, Asplenio cuneifolii-Quercetum petraeae), which includes Central European thermophilous oak forests distributed outside the range ofQuercus pubescens and some other submediterranean species.  相似文献   

20.
A new speciesCoronilla moravica (familyFabaceae) is described from the locality ?aklovy N of Uherský Brod in E Moravia, Czechoslovakia.  相似文献   

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