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1.
Background: Rattans are widespread throughout paleo-tropical forests; however, there is no information on their contribution to above-ground biomass (AGB).

Aims: This study established biomass baseline values for 11 different rattan species in a Malaysian primary forest, and calculated the overall rattan AGB contribution and dynamics during two years.

Methods: All rattan stems in five 100 m × 100 m study plots were counted in 2011 and 2013. Biometric non-invasive measurements were carried out on 11 climbing and non-climbing species and total rattan biomass for both years calculated was compared.

Results: Rattans contributed with 3.1 Mg ha?1 to the forest AGB. There was no significant change in rattan biomass between the years.

Conclusions: These preliminary results are the first published on the AGB contribution of rattans to Malaysian primary forests. Further studies are required to ascertain values across forest types and over time to reliably estimate the contribution of rattan species to ABG and carbon sequestration.  相似文献   

2.
Abstract

A synthesis is presented of some research results on the structure and dynamics of populations with respect to the phytocoenosis structure. The first aspects to be considered are concerned with the dynamism, distribution and reproductive strategy of Anemone nemorosa: the vegetation structure either favors or inhibits the various reproductive strategies, thereby influencing the distribution pattern of the species. The second area of the present study is the demography and quantitative structure of Cytisus sessilifolius populations with respect to the problematic of secondary successions: the first results obtained open up interesting prospectives on the relationship between the vegetation dynamics and the frutescent populations structure.  相似文献   

3.
Abstract

A contribution to the fossil Silicoflagellates of the late Miocene in Central Italy. - A microscopic analysis of fourteen diatomite samples from a Messinian (late Miocene) stratigraphic series, in central-eastern Italy, has been carried out in order to verify the presence of Silicoflagellates. The skeletons of eight taxa were found in good condition and identified. The most abundant and continuous in the stratigraphic series examined are Dictyocha fibula and Distephanus speculum, also known in the present-day seas; Cannopilus sphaericus, a very rare and interesting species extinct in the Miocene, is limited to only two samples. On the basis of the Silicoflagellates found, it is possible to suggest that they lived in an open sea with 30–40‰ salinity and a temperature of 10–20°C. A very similar situation is present nowadays in the middle-western Adriatic Sea.  相似文献   

4.
Abstract

The present paper deals with the embryological studies of ten species of Taraxacum, out of which nine polyploid species are apomictic and one diploid species T. wallichii shows normal sexual behaviour. Occasional formation of normal megaspore tetrads and triads are observed in tetraploid and triploid species.

Autonomous development of endosperm from the secondary nucleus seems to be the rule. The growth of endosperm is relatively slow.  相似文献   

5.
Abstract

New or interesting plants in the mountainous basin of the Esino (Marche region).—The Authors point out a discovery of 46 species of remarkable importance concerning the flora of the Marche region in the mountainous basin of the Esino. Among these, Poa chaixi and Monotropa hypopithis have been discovered in this region for the first time.  相似文献   

6.
Abstract

Mycoflora of Silver fir (Abies alba Mill.) stumps. - This work is a first contribution to the knowledge of the mycoflora colonizing Silver fir (Abies alba Mill.) stumps in Italy.

Autochthonous fungal species were isolated from the wood of A. alba stumps from three different sites in the Tuscan Apennines.

Frequency values for the isolated species and taxonomic groups were calculated.

Deuteromycetes (57–82.5%) occurred more frequently than basidiomycetes (5–36%), phycomycetes (0.7–11.6%) and ascomycetes (0–1%). The most common genera were found to be: Aleurodiscus, Penicillium, Phellinus, Phialophora, Scytalidium, Sistotrema and Trichoderma.

An effective method of isolation from wood is also described.  相似文献   

7.
Abstract

New or interesting Lichens of italian coasts. — The autor describes a lichen new to Italy, Acarospora microcarpa (Nyl) Wedd, a mediterranean species, found in southern France only hitherto. The lichen was gathered on the tufs rocks of the Isle of Procida; so the species is classed among the cryptogamic flora of phlegrean tufs.

The presence of Acarospora trachytica Jatta on the isle of Procida is therefore indicated, a species that is somewhat rare and known so far only on the Island of Ischia and Vesuvius.

Some new places for the marine lichen, Verrucaria symbalana Nyl. are reported, and the particular ecological interest of the species and its full geographical placement considered.

Finally, new places for Lichina confinis Ag., in Italy are given. This is a marine species of considerable ecological interest.  相似文献   

8.
Abstract

First report of the presence of Spirulina labyrinthiformis Gomont in Thermae of Segesta (Sicily). – The study on the algal ecology of thermal waters in Segesta shows for the first time the occurrence of Spirulina labyrinthiformis Gomont. It is interesting to note the high population density of Spirulina against the other components of the algal microflora, represented by the species of Cyanophyceae and Bacillariophyceae and that of photosynthetic bacteria.  相似文献   

9.
《Journal of bryology》2013,35(4):287-291
Abstract

Mnioloma fuscum, a liverwort species known to date primarily from tropical-montane regions, is reported for New Zealand for the first time. Its occurrence in New Zealand is unexpected as the next nearest known site is believed to be the Solomon Islands, some 3500 km distant. The occurrence of Mnioloma fuscum in New Zealand highlights the contribution tropical regions have made to the composition of New Zealand's hepatic flora.  相似文献   

10.
Summary

A list of fifty five species of microfungi collected on needles, twigs and cones of pines from Rhum (Hebrides, Scotland) is presented. Of these, Sporonema diamandidis and Xylohypha ortmansiae are published as new species, and Rosellinia obliquata is reported as new to the British list. A further thirty three species are new to the Rhum list. Five of the new or interesting species are described, four illustrated, and the unusual status of Lophodermium seditiosum on the island is briefly noted.  相似文献   

11.
《Journal of bryology》2013,35(4):288-295
Abstract

This contribution is a result of collaborative work based on the fieldwork organized during a workshop of the Tropical Bryology Group on Mascarene bryophytes in September 2008, and also from previous unpublished records of the authors. We add 35 new taxon records (17 mosses and 18 liverworts) as well as five other interesting records for Réunion Island (Mascarene Archipelago). Grimmia austrofunalis Müll. Hal., Sphagnum magellanicum Brid. subsp. magellanicum, Didymodon tectorum (Müll. Hal.) K. Saito, Anastrophyllum revolutum Steph. and Lejeunea exilis (Reinw. et al.) Grolle are reported for the first time for Africa. Syrrhopodon vardei L. T. Ellis, Ceratolejeunea papuliflora Steph. and Xylolejeunea grolleana (Pócs) X.-L. He & Grolle, previously known as endemic from Madagascar, are here recorded for Réunion. The latter species is also illustrated with SEM pictures.  相似文献   

12.
Abstract

L'autore riferisce sui primi ritrovamenti di Aphyllophorales ad Is Arenas, pineta litoranea che si estende sulla costa occidentale della Sardegna, in provincia di Oristano. Le specie segnalate sono 48 e tra queste: Crustoderma dryinum (Berk. & Curt.) Parm., Hyphoderma malençonii (Manjón & Moreno) Manjón, Moreno & Hjortstam, Peniophora tamaricicola Boid. & Malençon, Phanerochaete magnoliae (Berk. & Curt.) Burds., Thanatephorus cucumeris (A.B. Frank) Donk, sono risultate nuove per la micoflora italiana.  相似文献   

13.
Background: Boreal forest understory plant communities are known to be resilient to fire – the species composition of stands after a fire is quite similar to the pre-fire composition. However, we know little about recovery of individual plants within particular locations in forest stands (i.e. plot-level changes) since we usually do not have pre-fire data for plots.

Aims: We wanted to determine whether species recruited into the same or different locations in a Pinus banksiana stand that experienced a severe wildfire.

Methods: We used pre-existing permanent plots to evaluate the cover of understory after an unplanned wildfire.

Results: Across the entire stand nine of 47 species showed a significant change in cover. The largest change in a plant functional group was in the mosses, with all species present before fire being eliminated. There was no change in species diversity or total cover. At the plot level, species composition showed a much greater change. An average of 47% of the species present in a plot before the fire were absent in the same plot after the fire, and the total species turnover in plots was 88% of the species present before the fire. The plots showed a similar shift in species composition.

Conclusions: These results confirm that boreal forest communities show a high degree of resilience to fire, but within a forest stand species will be found in different locations following fire, potentially exposing them to a different set of biotic and abiotic conditions in these new locations.  相似文献   

14.
Introduction. During a field excursion in Guizhou Province, China, we collected some interesting moss specimens with branch leaves subulate in the upper part, partially and variably bistratose laminae, and a Macromitrium-like epiphytic growth habit on tree trunks. We present morphological and phylogenetic arguments for recognising these plants as a new moss species in the genus Macromitrium Brid. (Orthotrichaceae).

Methods. We compared the morphology of the potential new species with closely related species of Macromitrium, and constructed a phylogenetic tree based on ITS2, trnL and trnG including sampling from 14 other morphologically similar species of Macromitrium.

Key results. The proposed new species belongs to the genus Macromitrium (Orthotrichaceae, Musci). It is closely related to M. gymnostomum Sull. & Lesq. in the phylogenetic tree and according to gametophytic morphological features, represents a hitherto undescribed species.

Conclusions. A new moss species, Macromitrium maolanense Zeyou Zhang, D.D.Li, Jing Yu & S.L.Guo, is described and illustrated. The new species can be distinguished from all congeners by the combination of the following features of the branch leaves: (1) oblong-lanceolate, lanceolate to linear-lanceolate, gradually narrowed to an easily broken subula; (2) rather obscure upper and medial cells, often with blackish stains among cells, densely pluripapillose; (3) variably and partially bistratose laminae in the upper 1/3 portion; (4) basal cells clear, hyaline and smooth, those near costae forming a ‘cancellina region’; and (5) with numerous brownish, clavate gemmae on upper portion. We also discuss the principal distinctive characters separating the new species from its nearest congeners.  相似文献   

15.
Abstract

Desmids of the peat-bog of Vedes (Trento, North-Italy). A list of 27 Desmids s.l. (Desmidiaceae, Closteriaceae and Mesotaeniaceae) observed in some samples coming from the peat-bog of Vedes (Trento, North-Italy) is reported. This is a high moor bog situated at an altitude of 1496 m and rich in Sphagnum species (Sphagnum medium, S. fuscum, S. robustum, S. laricinum, etc.). The most interesting Desmids found are: Actinotaenium cucurbita, A. crassiusculum, Bambusina brebissonii, Penium polymorphum, Tetmemorus brebissonii, T. laevis, Closterium intermedium, Cosmarium amoenum, Euastrum insigne, Netrium digitus and Staurastrum erostellum, the last one being a very rare species found for the first time in Italy; thirteen entities are new for the algal flora of Trentino-Alto Adige.  相似文献   

16.
Abstract

The Xylocopinae contains four tribes with species which show a range of nesting habits, from solitary to social. The Manueliini is the sister group to all other Xylocopine tribes, with one genus, Manuelia, of three species found mainly in Chile. This is a solitary genus, whose biology is scarcely known for two species, M. gayatina and M. gayi, and so far completely unknown for M. postica. This paper reports on nesting substrates, nest architecture, nesting behaviours, life cycle, and interactions between females at nesting sites, for M. postica. The results indicate that M. postica presents some features which are typical of solitary life, and also some features which are unusual in solitary bees but have been reported in phylogenetically more apical social species. Our findings open interesting questions on the ecological scenarios involved in the evolution of sociality within the Xylocopinae.  相似文献   

17.
Abstract

Observations on three interesting Ceramiales from the Mediterranean Sea are reported; Ceramium incospicuum Zanardini, Polysiphonia setacea Hollenberg and Rodriguezella pinnata (Kützing) Schmitz ex Falkenberg. The male reproductive structures on the genus Rodriguezella are described for the first time.  相似文献   

18.
Summary

Grasshoppers and crickets of Montenegro have never been systematically studied. In this paper we present new distribution records of 119 Orthoptera species from Montenegro, sampled at 116 localities in different parts of the country in the period between 2010 and 2017. We also present records of older material deposited in the collection of the Hungarian Natural History Museum, Budapest. Oecanthus dulcisonans Gorochov, 1993 is recorded for the first time in Montenegro. Most of the areas investigated in this paper were never studied before, so our data represent the first information on Orthoptera of these parts of Montenegro.  相似文献   

19.
《Journal of bryology》2013,35(4):309-312
Abstract

The families Pterigynandraceae and Rigodiaceae are reviewed for Africa with reference to the collections made by the BBS Expedition to Mt Mulanje, Malawi in 1991. The single African species of Rigodium (Rigodiaceae) is reported to be quite frequent on Mt Mulanje, and three of the four species of Trachyphyllum (Pterigynandraceae) found in Africa (T. gastrodes, T. dusenii and T. inflexum) are reported, the latter two for the first time from Malawi. On present limited evidence, Malawi seems to be a centre of diversity of the genus.  相似文献   

20.
《Journal of bryology》2013,35(4):360-362
Abstract

The family Sematophyllaceae is a difficult family to treat in Africa because of the large number of species described without any subsequent revision or monography and, despite the many collections mentioned in this paper, only two species had previously been identified from Malawi. A total of four species in four genera (Gammiella, Mρacrohymenium, Radulina and Wijkia) are recorded in this paper, all but one new to Malawi. The two remaining genera (Sematophyllum and Trichosteleum) present additional difficulties of identification, and will be dealt with separately.  相似文献   

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