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1.
Valbuena  L.  Vera  M.L. 《Plant Ecology》2002,161(1):137-144
The germination responses of 4 shrubs, Erica arborea, E. australis and Daboecia cantabrica (Ericaceae) and Genistella tridentata (Papilloneaceae) in relation to variable light and temperature regimes was determined for freshly harvested and 1 year-old seeds. Temperature treatments consisted of 5 levels of heat from 60 °C to 140 °C and two levels of exposure time, 2 and 4 min. We also examined the effects of stratification on germination of Erica arborea and E. australis. The seeds of Erica arborea were the first to begin germinating and the freshly collected ones reached the highest level of germination with light. The seed viability of E. arborea was affected by storage, decreasing germinative capacity, while mean germination in Erica australis ssp. aragonensis was lowest. However, the stored E. australis seeds germinated better than the fresh ones. Germination response to ageing varies in Daboecia cantabrica depending on heat pretreatment. A significantly positive effect of high temperature and exposure time on germination was shown in Daboecia cantabrica and Genistella tridentata. Cold pre-treatment of seeds did not enhance germination.  相似文献   

2.
The aim of this research was to evaluate plant diversity and the relationships between the distribution of Raunkiaer life forms and community structure, and species richness, at different successional stages in communities of Quercus ilex L., Erica arborea L. and Sarcopoterium spinosum (L.) Spach., distributed as enclaves in Sinop Province. Permanent sample plots were selected to determine plant diversity. The cover percentage of each plant species was recorded monthly during two vegetation periods. Raunkiaer life forms, and the Shannon–Wiener, Evenness, Simpson and Margalef indexes were determined. Twenty-three species in Quercus ilex, 96 species in Erica arborea, and 148 species in Sarcopoterium spinosum were identified. Hemicryptophyte dominancy was observed followed by phanerophytes in the Q. ilex community, and therophyte and hemicryptophyte dominancy in the E. arborea and S. spinosum communities, respectively. It was determined that the S. spinosum community was the most heterogeneous community while the Q. ilex community was more uniform than other communities. The variation in diversity indexes, homogeneity, and composition of life forms among communities adopting a similar climatic environment could result from a differentiation of environmental factors, which impact on community structuring, from biotic to abiotic at different successional stages of Mediterranean communities.  相似文献   

3.
This paper is part of a wider study in which different combinations of species were assayed for the revegetation of experimentally burnt heathlands. In this particular case, we determined whether there was any interaction between the dominant species, Erica australis, which recovered by vegetative resprouting, and the only successful woody species sown, Cytisus sp., eight years after fire and seven years after sowing. A detailed study was carried out on each square metre of cover and height of both species in three 160 m2 plots. Total cover exceeded 100% in all subplots sown with Cytisus, whereas it did not reach 65% in the others, when both species coexist together. There was an inverse correlation between the covers of both species and a positive correlation between the height of Erica australis and the cover and the height of Cytisus. There was no significant difference in Erica cover in plots sown with Cytisus and plots not sown. There could be some competition for light, but both species are capable of coexisting with high canopy overlap, for at least some time. Cytisus is expanding from the seeded subplots, suggesting that the dense cover of Erica australis does not impede the establishment of Cytisus. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

4.
A key is provided for the identification of the thirty-eight psyllid species recorded from Alaska. Additional notes on host plant and distribution are given for each species. The species are: Aphalara manitobaensis Cald.,A.nigra Cald., Craspedolepta alaskensis (Ash.), C.nebulosa (Zett.) ssp. kincaidi (Ash.), C. schwarzi (Ash.), C.subpunctata (Förster), Psylla alaskensis Ash., P.betulaenanae Oss., P.breviata Patch, P.fibulata Crawf., P.floccosa Patch, P.galeaformis Patch, P.haliaeeti sp.nov., P.hamata Tuthill, P.highwoodensis sp.nov., P.jenseni sp.nov., P.kananaskensis Hod., P.ledi Flor., P.longiforceps sp.nov., P.minor Crawf., P.macleani sp.nov., P.myrtilli Wag. ssp. canadensis Hod., P.palmeni Löw, P.phlebophyllae sp.nov., P.rara Tuthill, P.rufipennis sp.nov., P.sinuata Crawf., P.striata Patch, P.stricklandi Crawf., P.toolikensis sp.nov., P.zaecevi Sulc, Trioza albifrons Crawf., Trioza artica sp.nov., T.atkasookensis sp.nov., T.incerta Tuthill, T.salicivora Reut. (=T.maura auctt. N.Amer.), T.stylifera Patch, Trioza sp.nov. (undescribed). All the newly described species were collected on Salix. The Alaskan fauna is made up of four major components: 1, true Arctic species; 2, Arctic/subarctic species; 3, subarctic/alpine species; 4, northern forest zone species. Eight of the Alaskan psyllids exhibit an holarctic distribution and there is a strong faunal affinity with similar areas in northern Scandinavia: the same four genera recur throughout the northern holarctic. There is strong circumstantial evidence that certain psyllid species are parthogenetic over part of their range, particularly in arctic/alpine situations.  相似文献   

5.
The resistance to experimental, highly frequent disturbance has been analysed in three congeneric, strong-resprouter species (Erica australis, E. scoparia and E. arborea) that co-occur in heath-dominated communities of the northern side of the Strait of Gibraltar, southern Spain. To do so, mature individuals of the three species from a long undisturbed location were clipped at the ground level every sixth month during two years. The relationship between the resprouted biomass dry weight (as indicative of the resprouting vigour) and the upper surface area of the lignotuber along the experiment was established separately for each species at each clipping event by means of linear regressions analysis. The resprouting vigour of the three species was compared by means of independent one-way ANOVAs within each clipping event. Resprouting vigour decreased after recurrent clippings in the three species. Nevertheless, significant differences between species in this loss of resprouting vigour were detected, being E. scoparia the most resistant to the experimental, highly frequent clipping. It is concluded that experimental levels of recurrent disturbance may help to find out differences in resilience within similar (taxonomically, morfologically and/or ecologically), strong-resprouter plant species. Considering the history of forestry management in the nothern side of the Strait of Gibraltar, differences in this regard between the three Erica species may contribute to explain their somewhat segregated ecological distribution in this region.  相似文献   

6.

Collections of rhinebothriidean cestodes (Platyhelminthes) from Australian batoid elasmobranchs revealed the presence of a number of new genera and species. Ruptobothrium louiseuzeti n. g., n sp. is described from the reticulate whipray, Himantura australis Last, Naylor & Manjaji-Matsumoto, from off the Northern Territory and Mixobothrium queenslandense n. g., n sp. is described from the green sawfish, Pristis zijsron Bleeker, from off north-eastern Queensland. Two new species of Rhabdotobothrium Euzet, 1953 are described: Rhabdotobothrium meridionale n. sp. from the southern eagle ray Myliobatis tenuicaudatus Hector from off South Australia and Rhabdotobothrium anoxypristidis n. sp. from the narrow sawfish, Anoxypristis cuspidatus (Latham) from off north Western Australia. A new species of Scalithrium Healy & Reyda, 2016, Scalithrium australiense n. sp., is described from the reticulate whipray, Himantura australis Last, Naylor & Manjaji-Matsumoto, from off northern Western Australia. Scalithrium smitii (Shinde, Deshmukh & Jadhav, 1981) n. comb. is reported from Australian waters for the first time in the black spotted stingray Maculabatis toshi (Whitley) from off northern Western Australia. New host and geographical records are provided for Stillabothrium jeanfortiae Forti, Aprill & Reyda, 2016 from the brown whipray Maculobatis toshi (Whitley) and the black-spotted whipray, Maculabatis cf. astra (Last, Manjaji-Matsumoto & Pogonoski) from Moreton Bay in southern Queensland.

  相似文献   

7.
Three new species of small mazocraeids are described from the Swan River Estuary, Western Australia. The first of these,Pseudanthocotyloides mamaevi n. sp. is found onEngraulis australis; the other two,Neomazocraes rohdei n. sp. andMazocraeoides australis n. sp., onNematalosa vlaminghi. The diagnosis of the genusPseudanthocotyloides is amended and the new species is discussed with reference to a closely related but undescribed form reported to have caused a mass mortality of the Japanese anchovy,E. japonica, in Japanese waters. The species of the above three monogenean genera are listed: six species ofMazocraeoides are regarded as species inquirendae.  相似文献   

8.
Summary The two dominant species of the Corsican mattoral,Arbutus unedo L. andErica arborea L., can produce abundant sprouts from the lignotuber not only immediately after fire but also more or less continuously in the absence of major disturbance. The lignotuber appears to be more important during the early stages of development; the result is an increase in the number of sprouts during the 25 years following the establishment of the individuals. Later the lignotuber seems to lose the ability to ensure the development of new basal sprouts. A hypothesis is that the presence of a lignotuber is related to the growth form.Arbutus unedo andErica arborea show behaviour intermediate between acrotony and basitony, as the shoots show acrotony, and continuous sprouting is characteristic of basitonic species. The fact that sprouting from the lignotuber is not necessarily a result of fire suggests that the relation between fire and vegetation in the Mediterranean region should be reconsidered.  相似文献   

9.
Three new genera, one new subgenus, and 13 new species (Strogulomorpha separata sp. n., S. davidi sp. n., S. proxima sp. n., Luzarida lata sp. n., Luzara venado sp. n., L. sapani sp. n., Ucayacla pulchella gen. et sp. n., Peruzara atalaya gen. et sp. n., P. loreto sp. n., Amazonacla imitata gen. et sp. n., A. primitiva sp. n., Leptopsis (Leptopsis) ucayali sp. n., and L. (Aberracla subgen. n.) morona sp. n.) are described. The composition of the tribes Paragryllini and Luzarini and of the genera Luzarida Heb. and Luzara Walk is discussed. The new synonymies Luzarida Hebard, 1928 = Ecuazarida Nischk et Otte, 2000, syn. n.; Lerneca Walker, 1869 = Doposia Otte et Perez-Gelabert, 2009, syn. n.; Nemoricantor Desutter-Grandcolas et Hubbell, 1993 = Kumalorina Otte et Perez-Gelabert, 2009, syn. n. are given. The systematic position of some previously described species is corrected.  相似文献   

10.
The Aslauga purpurascens complex is revised and six species are recognized: purpurascens Holland, marshalli Butler (=purpurascens marginaria Talbot syn.n.), latifurca sp.n., orientalis sp.n., atrophifurca sp.n. and australis spn. All species are described and illustrated and keys provided for their identification. Characters used in previous studies and in the present study are discussed and the literature is reviewed. The biology of the species is discussed with special reference to the appetitive sexual behaviour of adult males and to possible hostspecificity in larval predation of membracids and coccids. The significance of the geographical distribution of the species is examined.  相似文献   

11.
The vegetative resprouting of mediterranean maquis shrubby species was examined eight years after fire. Post-fire regeneration occurs through the resprouting of stumps. All species (Quercus ilex L., Phillyrea latifolia L., Arbutus unedo L., Erica arborea L., Pistacia lentiscus L.) show a rapid growth in the first years after fire, and a decrease already from 4th–5th year.All the species survived the fire and reconstituted a community similar to that unburned in a relatively short time span.  相似文献   

12.
The higher growth rates of resprouting shoots compared with those of mature plants in resprouter woody species are supported by higher rates of photosynthesis and transpiration. In this contribution we hypothesize that species with higher resprouting vigour will show a larger enhancement of photosynthesis in resprouting shoots. We test this hypothesis by comparing gas exchange and leaf parameters between resprouting and mature plants in Erica scoparia and E. australis. These two Erica species co-occur in Mediterranean heathlands of the Strait of Gibraltar. Erica scoparia has a higher rate of post-disturbance starch recovery than E. australis, which makes it more resistant to recurrent disturbance. We tested the hypothesis that enhancement of photosynthesis and water use characteristics of resprouting shoots compared with mature plants should be more pronounced in E. scoparia. In both species, resprouts had higher efficiency in the use of light and higher maximum net photosynthesis than mature shoots. However, contrary to expectations, differences in the photosynthetic performance between resprouts and mature plant shoots were larger in E. australis. Higher root to shoot ratios in resprouting E. australis plants, determined by their slower above-ground recovery, together with stronger demand from carbon sinks might explain this result.  相似文献   

13.
Four new xarifiid copepods are described. They were found in association with the scleractinian coral Pavona explanulata (Lamarck) occurring in shallow water reefs off Yenliao in northern Taiwan. The four species are: Xarifia capillata n. sp., X. parva n. sp., X. pavonae n. sp. and X. taiwanensis n. sp. They were found together in a single washing of the host coral. Previously, 13 species of copepods have been found in association with nine species of Pavona Lamarck. More than half (7/13) of these symbionts are members of Xarifia Humes, 1960.  相似文献   

14.
The response of woody species to experimental burning, cutting andploughing was studied for a period of twelve years in a shrub community in NWSpain. The treatments represent the perturbations most frequently imposed bymanon these shrub communities throughout history. The response to burning is muchfaster than the response to cutting. The response to ploughing is slower due tothe regeneration mechanism that species use: germination. In general, thedominant species, Erica australis, influences theregeneration patterns of the rest of the species, which make up the community.There is a significant increase in the cover of woody species until the fourthyear, and of herbaceous species until the third year. Subsequently,Erica australis attains dominance, returning to itsoriginal spatial occupancy and cover values, removing the herbaceous speciesandnegatively influencing the growth of woody ones like Halimiumumbellatum, Halimium alyssoides and Quercuspyrenaica. Both Erica australis andChamaespartium tridentatum regenerated by sprouting in theburnt and cut plots, and by germination in the ploughed plot.Arctostaphylos uva-ursi only recovers after burning andploughing. Halimium alyssoides, Halimium umbellatum, Ericaumbellata and Calluna vulgaris regenerate bygermination in the three plots. Differences in cover values and spatialoccupancy during the first years of succession tend to be eliminated twelveyears after treatment and most of the species tend to recover their initialcover values. These shrubland communities have a high degree of resilience dueto the strong sprouting potential of the component species.  相似文献   

15.
Abstract. Soil samples were collected before and after an experimental fire on a heathland in the province of León (Spain). The seed banks were assessed by counting the numbers of seedlings appearing of Erica australis and Calluna vulgaris. A total of 2285 germinable seeds/m2 before burning and 1177 germinable seeds/m2 after the fire were estimated for Erica australis, and 90 and 690 germinable seeds/m2, respectively, for Calluna vulgaris. After the fire the number of germinable seeds/m2 of Erica australis had decreased, whilst there was a considerable increase in the number of germinable seeds/m2 of Calluna vulgaris. Neither seedlings nor sprouts of Calluna vulgaris had appeared in the field plots 10 months after the fire. Erica australis did recover mainly by sprouting after fire.  相似文献   

16.
Three species of Microthoracids, Lopezoterenia paratorpens n. sp., Trochiliopsis australis Foissner et al., 1988 and Discotricha papillifera Tuffrau, 1954, collected from Chinese coastal waters, were investigated using live observation and protargol staining methods. Lopezoterenia paratorpens n. sp. was characterized by its squarely shaped cortical papillae and by dorsal kineties which contained loosely distributed basal bodies. Trochiliopsis australis was revealed to have two oral membranelles, which was not recorded in the original report. Phylogenetic analyses were carried out based on SSU rRNA gene sequence data from each of the three species, and on other available data for microthoracids. The results showed that the order Microthoracida is not monophyletic because the family Discotrichidae, which contains L. paratorpens and D. papillifera, forms a clade separated from the “core” Microthoracids clade. The topologies of the maximum likelihood and Bayesian inference trees, along with the distinct morphological characteristics found previously, suggest that the family Discotrichidae should not be assigned to the order Microthoracida. We propose to designate a new order, Discotrichida n. ord. which diagnosed as: flattened ciliates with conspicuous cortical papillae on both dorsal and ventral faces, rod‐shaped mucocysts, and an asymmetric cytopharyngeal basket. Also, the fact that Leptopharynx clusters with the assemblage including T. australis, and Pseudomicrothorax is located distantly from Leptopharynx indicates that the classification of Pseudomicrothoracidae and Microthoracidae by Foissner (1985) is justified.  相似文献   

17.
The family Iravadiidae is found to be polyphyletic in a molecular phylogenetic analysis using a subset of Australian taxa. Taxa previously assigned to Iravadia form a monophyletic clade, but Nozeba topaziaca clusters with Auricorona queenslandica n. gen. and n. sp. in an unnamed family related to Tornidae. Aenigmula criscionei n. gen. and n. sp., an iravadiid-like species from the Northern Territory, belongs to another unnamed family related to Caecidae, Calopiidae and Clenchiellidae. A systematic revision of some Australian ‘iravadiids’ raises the subgenera Fluviocingula and Pseudomerelina to full generic rank and reinstates two former synonyms of Iravadia (Fairbankia), Pellamora and Wakauraia, as genera. The species formerly identified in Australia as Iravadia quadrasi is recognised as three allopatric species; Iravadia pilbara n. sp. and the reinstated species Iravadia goliath and Iravadia quadrina. Pellamora splendida n. sp., from Western Australia, is recognised as distinct from Pellamora australis, and Fluviocingula superficialis n. sp. from Fluviocingula resima. Wakauraia fukudai n. sp. is recorded from central Queensland.

http://zoobank.org/urn:lsid:zoobank.org:pub:1B9917F6-48B2-4597-85C1-F90BA9093475  相似文献   


18.
Three species of the genus Trichodina are reported from the gills of marine fishes in south-eastern Tasmania, Australia. Two of these species are new: T. australis n. sp. from five atherinid fish species, Atherinosoma microstoma, Leptatherina presbyteroides, Kestratherina brevirostris, K. esox and K. hepsetoides; and T. nesogobii n. sp. from Nesogobius sp. 1. One previously reported species, T. jadranica Raabe, 1958, was also found on Nesogobius sp. 1.  相似文献   

19.
We studied the diversity of oomycetes in a declining reed belt (Phragmites australis) of Lake Constance, Germany, using conventional baiting with specific reed and standard oak baits, accompanied by molecular techniques. Apart from an Aphanomyces sp. and a Phytophthora sp., baiting from reed rhizosphere samples from flooded, as well as drier, littoral sites revealed only Pythium spp. A total of 67 oomycete isolates was classified according to PCR-RFLP banding patterns and ITS sequencing, and 18 different sequence types could be separated. The majority of these seemed previously unknown species, as indicated by the degree of similarity to those deposited in nucleotide databases. Species communities in both flooded and drier habitats or both reed and oak baits clearly differed from one another, and only few species occurred in both dry and flooded sites, or in both oak and reed baits. A frequently occurring group of related Pythium species appeared to be specifically associated with reed, and these were the only species that proved pathogenic towards this host in vitro. Our study proved that unexplored natural ecosystems harbour diverse communities of oomycete species with specific habitat and host preferences within close-by, but ecologically contrasting, sites. Among the species isolated, those associated with the predominating plant might accumulate and thus may be reed pathogens of considerable importance.  相似文献   

20.
The aim of this study is to compare the recovery dynamics in three shrub communities subjected to experimental burning and cutting, and situated on an altitudinal gradient. Climatic features are different in each area, but all had the common characteristic of very homogeneous vegetation cover before the disturbances, with only one shrub species clearly dominant, a different taxon in each area, and with different regeneration strategies. The first area was a heathland dominated by Calluna vulgaris, situated at an altitude of 1600 m, with a continental climate (mean annual precipitation 1320 mm). The second area was a heathland dominated by Erica australis, located at an altitude of 1000 m (mean annual precipitation 840 mm). The third area was a Cistus ladanifer shrubland, located at 900 m altitude, with a Mediterranean climate similar to that of the previous area, but with lower mean annual precipitation (470 mm). Erica australis recovers by vegetative resprouting, but Cistus ladanifer is an obligate seeder, as is Calluna vulgaris in these areas. Each experimental disturbance was carried out over 100 m2 in each area. Post-fire recovery is faster in Cistus ladanifer: 2 years after burning there was 40% cover vs. less than 20% in the other two species. However, recovery after cutting was similar for Cistus ladanifer and Erica australis. Calluna vulgaris recovers very slowly, with cover values below 20% even 10 years after both disturbances. Cover of dominant shrub species is negatively correlated with cover of herbaceous species. So different recovery of dominant species lead a different community dynamic in each area.  相似文献   

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