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1.
Phytosociological analysis of savanna and forb-rich communities in the Pinar del Rio Province was done in the area of Remates de Guane; one locality lies on the seashore in the western part of the province. Altogether six associations were distinguished. Five of them, viz.Sclerio curtissii-Centelletum erectae, Schultezio guianensis-Rhynchosporetum fascicularis, Cassio diphyllae-Hypericetum stypheloidis, Polygalo squamifoliae-Dichromenetum seslerioidis andPhyllantho juncei-Aristidetum, all newly described in this paper, are classified into the order ofAcoelorapho-Colpothrinacetalia Bal.-Tul. inBal.-Tul. etCapote 1985 with two alliances. One association, thePaspalo debilis-Asteretum grisebachii Bal.-Tul. etCapote 1992, was put into the order ofAsteretalia grisebachii Bal.-Tul. inBal.-Tul. etCapote 1992 with one alliance bound to inland moving dunes. The plant composition reflects soil quality, above all the water regime. Very interesting is the presence of theByrsonimo crassifoliae-Andropogonetalia teneris-species in the association ofPolygalo-Dichromeneteum seslerioidis indicating the rich presence of stones in the upper part of the soil profile.  相似文献   

2.
This communication describes a new savanna-like community, theBletio purpureae-Andropogonetum gracilis Balátová-Tulá?ková etR. Capote ass. nov., found in the woodless eastern part of the Sierra del Rosario Mountains (western part of Cuba). From the phytosociological point of view, it belongs to the allianceAchlaenion piptostachyae Balátová-Tulá?ková all. nov., the orderAchlaenetalia piptostachyae Balátová-Tulá?ková ord. nov., and the classSclerio baldwinii-Andropogonetea gracilis Balátová-Tulá?ková cl. nov. In the area under study four subassociations were distinguished: theBletio-Andropogonetum typicum Balátová-Tulá?ková et.R. Capote subass. nov., theB.-A. rhynchosporetosum fascicularis Balátová-Tulá?ková etR. Capote subass. nov., theB.-A. cassietosum aeschynomenes Balátová-Tulá?ková etR. Capote subass. nov., and theB.-A. stenandrietosum droseroidis Balátová-Tulá?ková etR. Capote subass. nov.  相似文献   

3.
4.
This part of the study, referring to the previous syntaxonomic part (Ková? 1981), presents the results of a synecological examination of nine grassland communities of the Labe river basin covering roughly the following gradient of the alluvial hydrosere: theCerastio arvensi-Festucetum trachyphyllae trifolietosum pratensis, theArrhenatheretum elatioris typicum, theAlopecuretum pratensis, theStellario-Deschampsietum caespitosae phalaridetosum, theSerratulo-Festucetum commutatae, theMolinietum coeruleae brometosum, theAngelico-Cirsietum oleracei, theCaricetum gracilis typicum, theCaricetum buekii. The long-term study of ground-water level fluctuations showed their close connection to other characteristics of the meadow soils (soil type, moisture content, granulometric composition, capillary water-holding capacity, porosity, acidity, mineral nutrient contents, microbial activity, soil temperature) as well as to the development and distribution of the grassland communities associated with ecosystems of river alluvia. The formation and dynamics of the vegetation in the large river floodplain (at present exposed to the impact of far-reaching hydrological alteration) are explained as a consequence of changes in the natural ecocycles supporting the long-term stable character of the large river basin within the landscape.  相似文献   

5.
6.
In 74 natural populations of theMyosotis palustris andM. laxa groups from former Czechoslovakia three euploid and one aneuploid cytotypes were found that belong to the following species:M. nemorosa Besser, 2n=22,M. palustris (L.)Nath. em.Reichenb. inSturm, 2n=66,M. laxiflora Reichenb., 2n=66,M. radicans Opiz, 2n=66(64),M. brevisetacea (Schuster) Holub, 2n=66(64), andM. caespitosa C.F. Schultz, 2n=88. With the exception ofM. nemorosa, the chromosome numbers are published for the first time for the Czech Republic. The chromsome numbers, 2n=66, 2n=64 are found inM. brevisetacea, are new for the literature. The correlation between pollen size and ploidy level has been studied as well, and statistically significant differences were found between cytotypes belonging to different ploidy levels.  相似文献   

7.
A new species ofMyosotis ser.Palustres M. Pop.,Myosotis margaritae, related to theM. caespitosa group, is described from Bulgaria. Diploid chromosome number (2n=20) is given for the new species, and notes on its distribution, ecology and taxonomic relationships are presented.  相似文献   

8.
Two new hybrids in the genusThymus, Th. × indalicus Blanca et al., nothosp. nov. [=Th. baeticus Boiss. exLacaita ×Th. hyemalis Lange subsp.hyemalis] andTh. × enicensis Blanca et al., nothosp. nov. [=Th. hyemalis Lange subsp.hyemalis × Th. zygis Loefl. ex L. subsp.gracilis (Boiss.)R. Morales] are described. Until now no hybrids ofTh. hyemalis have been described, due to its early period of flowering and because it hybridizes with closely related species, making rather difficult the detection of such hybrids.  相似文献   

9.
The contribution presents phytosociological analyses of the savanna vegetation of Yaguaramas belonging to the classCuratello-Byrsonimetea Borhidi 1979. According to the plant composition, the plant communities under study belong to the orderByrsonimo crassifoliae-Andropogonetalia teneris Bal.-Tul. ordo nov., where two alliances were distinguished, namely theGuillemineo brittonii-Aristidion refractae Bal.-Tul. all. nov. and theByrsonimo crassifoliae-Andropogonion teneris Bal.-Tul. all. nov. The associationsSclerio interruptae-Rhynchosporetum subimberbis Bal. Tul. ass. nov., andPolygalo omissae-Andropogonetum diodontis Bal.-Tul. ass. nov. (both endemic) were classified in the former alliance while the associationByrsonimo crassifoliae-Andropogonetum teneris Bal.-Tul. ass. nov. is a representative of the latter. The following subassociations were distinguished: theSclerio interruptae-Rhynchosporetum subimberbis utricularietosum fimbriatae Bal.-Tul. subass. nov., theByrsonimo crassifoliae-Andropogonetum teneris typicum Bal.-Tul. subass. nov., and theByrsonimo-Andropogonetum sclerietosum interruptae Bal.-Tul. subass. nov.  相似文献   

10.
Considering an incomplete growth curve of the codGadus morhua,Knight (1968) questioned the asymptotic curvature of growth in fishes, which easily may be shown in complete growth curves illustrating the attainment of maximum size. It is also possible to calculate maximum size employing theFord-Walford formula. Maximum size, calculated in this manner, may also be used in theBertalanffy function. For other mathematical growth formulations different maximum sizes would be obtained. The numerical value of the maximum size depends upon the mathematical interpretation of the growth process. Therefore it always represents a mathematical parameter without biological meaning. It is shown that data ofKetchen (Forrester 1966) on growth in ♂ ♂ of the flat fishEopsetta jordani may be much better represented by the new growth formula (Krüger 1965) than by theBertalanffy function.  相似文献   

11.
Properties of the sugar carrier in Baker's yeast   总被引:3,自引:0,他引:3  
Incubation ofSaccharomyces cerevisiae cells withd-galactose induced the formation of galactose-utilizing enzymes, among them a monosaccharide carrier, apparently synthesized as a proteinde novo. The synthesis of the carrier preceded that of galactokinase by as much as 2 h. The inducible carrier shows a preference for monosaccharides with an axial hydroxyl group at carbon 4 of theC1 chair conformation or at carbon 2 of the1C chair conformation. Through its mediation, some sugars normally poorly transported (d-galactose,d-fucose,l-xylose,l-arabinose) can enter into the entire cell water, occupying then one more kinetic (and morphological ?) compartment than before induction. Some other monosaccharides, readily transported even by a constitutive carrier system (e.g.l-sorbose,d-xylose,d-arabinose) share the newly synthesized carrier.  相似文献   

12.
13.
Observations on parasites were made during a study of the following rice stem-borers in Sarawak (Malaysian Borneo):Tryporyza incertulas (Walker),T. innotata (Walker),Chilo suppressalis (Walker)C. auricilia (Dudgeon), andSeamia inferens (Walker). Egg-parasitism was often high, but that of the larval and pupal stages generally very low. Between 40–80% of theTryporyza eggs were parasitised byTelenomus rowani (Gahan), while 30–50% were attacked byTetrastichus schoenobii Ferrière. About 40–90% of the eggs ofChilo were parasitised byTrichogramma? japonicum Ashmead and 5–26% byTelenomus dignus (Gahan). Only 0.4–3% of theTryporyza larvae were parasitised by a Braconid,Rhaconotus schoenobivorus (Rohwer), whileBracon chinensis Szepligeti attacked 0.2–0.7% of the larvae ofC. suppressalis. Parasitism ofSesamia larvae byApanteles flavipes Cameron was equally low, never exceeding 2%. Pupal parasitism was somewhat higher.Tetrastichus israeli (Mani & Kurian) attacked 8% and 18% of the pupae ofC. suppressalis andS. inferens, respectively, while the Ichneumonid,Xanthopimpla stemmator (Thunberg) attacked up to 3% of the pupae of the former species. The immature stages of some of these parasites are described.  相似文献   

14.
The present study deals with African species ofSyzygiella Spruce,Allisoniella Hodgs. andGymnomitriaceae Klinggr. Three species ofSyzygiella Spruce,S. geminifolia (Mitt.) Steph.,S. concreta (Gott.) Spruce and one indeterminable species with orbicular leaves (known only in sterile condition) occur in Africa.Allisoniella nigra (Rodw.) Schust. represents a genus hitherto unreported for the African flora. The present knowledge ofGymnomitriaceae Klinggr. in subsaharan Africa is summarised; five species ofMarsupella Dum., one ofGymnomitrion Corda and five ofHerzogobryum Grolle are reported. Finally, some additions to the generaIsotachis Mitt.,Anastrophyllum (Spruce) Steph. andLophozia (Dum.) Dum. are presented.  相似文献   

15.
16.
The paper presents the results of phytocoenological studies of the helophyte vegetation occupying the litoral zone of three North Italian glacial lakes and of the tall-forb communities occurring on the Adige riverside. It uses the method of the Zürich-Montpellier school. The association complex occupying the littoral zone of Lake Caldaro, above all the associations ofCladietum marisci, Caricetum elatae, Juncetum subnodulosi, Schoenetum nigricantis, andSelino-Molinietum caeruleae resembles those of ± mesotrophic, calcium rich prealpine lakes studied in Switzerland, West Germany and Austria. On the other hand, the majority of the communities occurring in the littoral of the great Lake Monticolo are of dystrophic-mesotrophic character, manifested above all in the occurrence ofCaricetum diandrae, Peucedano-Caricetum lasiocarpae, andCaricetum elatae comaretosum, all with boreal distribution. The tall-forb associationLysimachio vulgaris-Filipenduletum has developed in the Adige riverside fromCalthenion and/or fromMagnocaricetalia communities as a result of interruption of mowing.  相似文献   

17.
18.
Caricetum gracilis Almquist 1929 ist eine Assoziation mit ausgedehnter eurosibirischer Verbreitung, es bewahrt sich jedoch in seinem ganzen Areal eine mehr oder weniger konstante zönotische Zusammensetzung, die durch das Grundmerkmal—die Anwesenheit vonCarex gracilis als Dominante (Kondominante) und Ädifikator, bedingt ist. Als ausschlaggebonder Faktor für die Entstehung der Gesellschaft kommt der Wasserhaushalt mit charakteristischer Abwechslung der Überschwemmungen und Austrocknungen zur Geltung. Die geographischen, klimatischen und bodenökologischen Unterschiede der Standorte ermöglichen eine weitere Gliederung der Assoziation inCaricetum gracilis Subass.typicum mit grösstem Verbreitungsgebiet, die in drei Varianten zerfällt, weiter inCaricetum gracilis comaretosum, dessen Areal an nördliche Teile Mittel- und Osteuropas gebunden ist und das in zwei Varianten zerfällt, und schliesslich inCaricetum gracilis naumburgietosum, das vor allem an das Herzynische Gebiet und den Nordrand der Karpaten gebundon ist.  相似文献   

19.
D. J. Greathead 《BioControl》1975,20(3):313-316
Attention is drawn to the transfer of the beanfliesMelanagromyza phaseoli (Tryon) andM. spencerella Greathead to the genusOphiomyia Braschnikov bySpencer (1973). The confusion over the nomenclature of theOpius spp. parasites is discussed and it is shown that the namesO. phaseoli Fischer andO. importatus Fischer should be used. Their introduction into Hawaii and establishment is briefly discussed in relation to their effectiveness as biological control agents. It is shown that they show a high degree of consistency of parasitism which has resulted in an acceptable degree of control ofOphiomyia phaseoli although there is no evidence that they act in a density dependent manner.  相似文献   

20.
A survey of the present vegetation of the Prokop Valley Nature Reserve revealed the following natural communities:Erysimo crepidifolii-Festucetum valesiacae Klika 1933,Alysso saxatilis-Festucetum Klika 1941,Allio montani-Sedetum albi Klika 1939,Helianthemo cani-Caricetum humilis ass. nova,Helianthemo cani-Seslerietum calcariae Klika 1933,Primulo veris-Seslerietum calcariae Zlatník 1928,Prunion spinosae Soó (1931) 1940 em.Tx. 1952,Prunion fruticosae Tx. 1952,Scabioso ochrolecae-Brachypodietum pinnati Klika 1932,Salvio nemorosae-Melicetum transsilvanicae ass. nova,Lathyro versicoloris-Quercetum pubescentis Klika 1932,Geranio-Peucedanetum cervariae (Kuhn 1937)Th. Müller 1961,Galio-Carpinetum Oberdorfer 1957,Aceri-Carpinetum Klika 1941,Luzulo-Quercetum (Hilitzer 1932)Passarge 1953,Genistion Böcher 1943,Mentho-Juncetum inflexi Lohmeyer 1953. For the anthropogenic vegetation another group of units was used. The species composition, environmental relationships an area of distribution are given for every mapping unit; characteristic soil properties for most important units of natural vegetation are also discussed.  相似文献   

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