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1.
西双版纳片断热带雨林蝶类群落结构与多样性研究   总被引:35,自引:1,他引:35  
杨大荣 《昆虫学报》1998,41(1):48-55
对西双版纳片断热带雨林蝴蝶群落结构和多样性进行了研究。样地内共收集蝴蝶9 204号,隶属于10科,62属,84种。主要成分是:粉蝶科(粉蝶属、迁粉蝶属)、凤蝶科 (凤蝶属、麝凤蝶属)、蛱蝶科(斐豹蛱蝶属、尾蛱蝶属),眼蝶科(幕眼蝶属、矍眼蝶屑)等属的种类。属、种以风蝶科最丰富;个体数量以粉蝶科最多;喙蝶科的属、种和个体数量最少。各样地的多样性指数、均匀度和种类丰富度是:热带原始雨林自然保护区>城子片断热带雨林>植物园片断热带雨林>曼峨片断热带雨林。  相似文献   

2.
How Tough are Sclerophylls?   总被引:2,自引:0,他引:2  
Fracture toughness was estimated for a 'least tough' path inthe leaves of woody species from three sclerophyllous plantcommunities. Most of the species from Mediterranean, tropicalheath forest and lowland tropical rain forest habitats had verytough leaves, with toughness generally 600-1300 J m-2, whichis two to four times higher than soft-leaved tropical pioneertrees. The toughest leaf (2032 J m-2), Parishia insignis, camefrom the canopy of the lowland rain forest. Leaves from theshaded understorey of the rain forest did not appear any lesstough than those from the canopy.Copyright 1993, 1999 AcademicPress Leaf fracture toughness, sclerophylly, Mediterranean vegetation, tropical forest  相似文献   

3.
The phylogenetic relationships among 12 species belonging tothree different genera (Shorea, HopeaandAnisoptera) of Dipterocarpaceaewere studied using random amplified polymorphic DNA (RAPD) markers.A modified CTAB DNA extraction protocol was used to obtain tannin-and polysaccharide-free genomic DNA from mature leaves. Clusteranalysis of data from six random primers placed the 12 speciesin three groups corresponding to their respective genera. Fourdistinct nodes ofShoreaspp. and two ofHopeaspp. could be identified.Anisopteramegistocarpaserved as an outgroup, and was unique when comparedto the other genera examined. RAPD profiles of five individualsofH. odoratawith six random primers were identical, suggestingthat there is little intraspecific variation in this species.The RAPD technique can thus be successfully applied for thestudy of phylogenetic relationships of this important groupof tropical timber trees.Copyright 1998 Annals of Botany Company Dipterocarpaceae,Anisopteraspp.,Hopeaspp.,Shoreaspp., RAPD markers, tropical timber trees.  相似文献   

4.
Five tropical epiphytes were examined for evidence of CrassulaceanAcid Metabolism (CAM), namely the orchids Eria velutina Lindl.,Dendrobium tortile Lindl. and Dendrobium crumenatum Sw., andthe ferns Pyrrosia adnascens (Forst.) Ching and Pyrrosia angustata(Sw.) Ching, family Polypodiaceae. Diurnal variations in leaftitratable acidity, diffusive conductance and water potentialwere measured at various levels of water stress. The three orchidsshowed typical CAM behaviour, namely large diurnal fluctuationsin leaf acidity, day-time closure and night opening of stomataand a very slow decline in water potential under stress. Theferns showed some evidence of CAM, but this was not as well-developedas had been reported for two other tropical epiphytic membersof the same family. Key words: Crassulacean acid metabolism, Tropical epiphytes, Water stress  相似文献   

5.
Measurements of populations of planktonic and micronektonicspecies from the Atlanto-mediterranean region (about 10,000specimens) have lead to improvements in Bergmann's rule relatingto the increase in size with latitude. There are three cases : Mediterranean specimens may be smaller(e.g. the mysid Eucopia hansent), equal to (e.g. the decapodcrustacean Gennadas elegans) or larger than Atlantic ones (e.g.the thecosomatous genus Cymbulia). All the species in the last group have their principal distributionin warm ocean waters. In the Atlantic, tropical species (e.g.the euphausiid Euphausia gibboides) decrease in size in thenorthern parts of their range while temperate species (e.g.the decapod crustacean Sergesles corniculum) decrease in sizetowards both the pole and the equator. The comparison with the number of vertebrae of fish, which increasesas does the size according to Jordan's rule, is interesting:though correct for cold water species (e.g. Merlucdus merluccius),this rule cannot be applied to warm water species (e.g. Merlucciussenegalensis). Thus, these rules must be corrected like this:- "a species reachesits maximal size in high, intermediate or low latitudes of itsarea if it has a boreal, temperate or tropical distribution"; - "the number of vertebrae increases with latitude for borealfish and decreases for tropical ones".  相似文献   

6.
The Labidocera pectinata species group is recognized as a uniquemonophyletic lineage within the primarily tropical Indo-WestPacific radiation of coastal water species encompassed by theLabidocera kroyeri complex. Both categories are defined andthe six species comprising the pectinata group, including twonew to science, are diagnosed. Review of available facts supportsthe proposal that L. bipinnata be ranked as a junior synonymof L. rotunda. Phylogenetic relationships within the group basedon sexually modified characters are assessed. Two geminate pairsof parapatric species are identified. The geographic rangesof one pair are adjacent in the Andaman Sea, those of the otherpair in the vicinity of Cape York, Australia. Each pair appearsto be a consequence of a relatively recent speciation event.The apparent phylogenetic intermediacy of L. japonica linkingthe two tropical species of Asia and the three from Papua-Australiasuggests an older sequence of trans-hemisphere spreading anddiversification.  相似文献   

7.
The distribution and composition of the holoplanktonic speciesof the family Typhloscolecidae are reported from 579 samplesobtained over an extensive area in the eastern tropical PacificOcean. The EASTROPAC Oceanographic Program collected the samplesin twelve cruises during five periods made between January–September1967 and January–April 1968. The 2105 specimens identifiedbelonged to three genera and four species. Typhloscolex muelleriand Sagitella kowalewski were dominant together, accountingfor 57–59% of the relative abundance and 36–49%of the occurrence. Travisiopsis dubia is recorded for the firsttime from the eastern tropical Pacific, and Travisiopsis lanceolatais reported in almost the same locality as its first recordin the surveyed region.  相似文献   

8.
In acidic soils, monomeric aluminium (Al3+) can reach levelsthat are toxic to plants, thus preventing many species fromgrowing there. Organic acids chelate Al and render it non-toxic.It has been shown that exudation of organic acids by Al-tolerantcrops increases their tolerance to Al. We have extended thisobservation to wild plants by comparing the ability of ten herbsto exude organic acids in response to elevated Al levels. Wehypothesized that exudation of organic acids was related tothe ability of plants to grow on Al-rich soils. Two grasseswere grown in rhizotrons in soils with 41 and 63 µM reactiveAl. Organic acids were sampled from root tips connected to anintact plant-root system.Deschampsia flexuosa (L.) Trin. exudedmore malic acid when grown in the soil with the highest Al content.Five forbs and five grasses were also exposed to three Al levels(0, 25 and 75 µM) in a hydroponic system.Rumex acetosellaL. and Viscaria vulgaris Bernh. increased exudation of oxalicacid and Galium saxatile auct. non L. and Veronica officinalisL. increased exudation of citric acid in response to elevatedAl. The distribution of the forbs in the field as describedby soil pH was negatively related to the amount of organic acidsexuded in response to Al. In contrast, none of the grasses exudedhigher amounts of organic acids with increasing Al concentrationin the hydroponic experiment. Copyright 2001 Annals of BotanyCompany Citrate, malate, aluminium detoxification, rhizotron, hydroponics, rhizosphere, Carex pilulifera,Deschampsia flexuosa , Festuca gigantea, Galium saxatile, Geum urbanum, Holcus mollis,Milium effusum , Rumex acetosella, Veronica officinalis, Viscaria vulgaris  相似文献   

9.
Statolith microstructure was studied in two abundant planktoniccranchiids, Cranchia scabra (56 specimens, 38–127 mm mantlelength, ML) and Liocranchia reinhardti (34 specimens, 99–205mm ML) sampled in epipelagic waters of the western part of theGulf of Guinea (tropical Atlantic). Growth increments were revealedin ground statoliths of both species. It was possible to distinguishtwo growth zones in statolith microstructure by their colourin reflected light of the microscope: the translucent postnuclearzone and pale white opaque zone. Assuming that growth incrementsin statoliths were produced daily, ages of the largest immatureC.scabra and L.reinhardti were 166 and 146 days, respectively.Both cranchiids are fast-growing squids with growth rates inlength resembling those of juveniles of tropical ommastrephidsand Thysanoteuthis rhombus. Liocranchia reinhardti grows faster:its growth rate in ML is approximately twice that of same-agedC.scabra. The life cycle of both cranchiids consists of twophases. During their epipelagic phase, C.scabra and L.reinhardtifeed and grow rapidly from paralarvae to immature young in theepipelagic waters, attaining 120–130 and 170–200mm ML by ages of 4–5 months, respectively. Then they changetheir life style to a deepwater phase.  相似文献   

10.
11.
Land use change and the global carbon cycle: the role of tropical soils   总被引:31,自引:4,他引:31  
Millions of hectares of tropical forest are cleared annually for agriculture, pasture, shifting cultivation and timber. One result of these changes in land use is the release of CO2 from the cleared vegetation and soils. Although there is uncertainty as to the size of this release, it appears to be a major source of atmospheric CO2, second only to the release from the combustion of fossil fuels. This study estimates the release of CO2 from tropical soils using a computer model that simulates land use change in the tropics and data on (1) the carbon content of forest soils before clearing; (2) the changes in the carbon content under the various types of land use; and (3) the area of forest converted to each use. It appears that the clearing and use of tropical soils affects their carbon content to a depth of about 40 cm. Soils of tropical closed forests contain approximately 6.7 kg C · m-2; soils of tropical open forests contain approximately 5.2 kg C · m-2 to this depth. The cultivation of tropical soils reduces their carbon content by 40% 5 yr after clearing; the use of these soils for pasture reduces it by about 20%. Logging in tropical forests appears to have little effect on soil carbon. The carbon content of soils used by shifting cultivators returns to the level found under primary forest about 35 yr after abandonment. The estimated net release of carbon from tropical soils due to land use change was 0.11–0.26 × 1015 g in 1980.  相似文献   

12.
Seven new species of the nudibranch genus Trapania Pruvot-Fol,1931 (Goniodorididae) are described from the Indo-West Pacificand an eighth species, T. japonica (Baba, 1935), originallydescribed from one preserved specimen from Japan, is redescribedfrom specimens collected in Hong Kong and tropical eastern Australia.Three of the new species are from temperate south-eastern Australiaand one from tropical eastern Australia. Two species are knownonly from Hong Kong and a third is recorded from the SudaneseRed Sea as well as Hong Kong. Only ten other species of Trapania have been described, sixof those from Europe, and one each from Brazil, California,Japan and New Zealand. The anatomy and external colour patternof these species is compared with that of the seven new species. (Received 12 December 1986;  相似文献   

13.
ODU  E. A. 《Annals of botany》1979,44(2):147-152
Optimum germination of spores of a Fissidens species occurredat a relatively higher temperature (30 °C) than the optimumgermination of those of a Racopilum species (25 °C). Subsequentprotonemal growth of the two mosses also showed the same differentialtemperature optima. The high-temperature requirement for germinationof Fissidens spores happens to coincide with the maturationand dispersal of the spores in the dry season, and apparentlyfavours the establishment of new shoots. Fissidens sp, Racopilum sp, tropical mosses, spore germination, temperature adaptation  相似文献   

14.
Predicting the Amount of Litterfall in Forests of the World   总被引:3,自引:1,他引:2  
LONSDALE  W. M. 《Annals of botany》1988,61(3):319-324
Total litterfall and leaf litterfall were examined for 389 forestsites throughout the world using multiple regression, consideringlatitude, altitude and precipitation as predictor variables.In its best model, Ig total litterfall was negatively related(r2 = 0.58) to latitude and altitude, while in the best modelfor lg leaf litterfall there was a negative relationship (r2= 0.35) with only one variable, latitude. When tropical forestswere considered separately however, lg leaf litterfall was positivelyrelated to precipitation, and negatively related to altitude(r2 = 0.43). The predictive power of all the regression equationswas low, with large percentage values of scatter about the fittedvalues for all equations. In addition, there was no relationshipbetween the ratio of non-leaf material to leaf material in thelitter with any of the predictor variables. Litterfall, forests, tropical forests, latitude, altitude, precipitation, regression models  相似文献   

15.
The apoplast of mature leaves of the tropical orchid OncidiumGoldiana was perfused with 0.5 mM p-chloromercuribenzenesulphonicacid (PCMBS) via the transpiration stream in order to test themode of phloem loading. The efficacy of introducing PCMBS byperfusion was shown by saffranin O dye movement in the veinsand leaf apoplast in control experiments. Photoassimilate exportas the result of phloem loading was measured by collection of14CO2-derived photoassimilates from the basal cut-ends of intactleaves. Phloem loading and translocation of photoassimilates was inhibitedby 89% in leaves perfused with PCMBS for 1 h. The effect ofPCMBS on leaf photosynthesis was minimal. The amount of radiocarbonfixed by PCMBS-treated leaves averaged 89% of control leavesperfused with distilled water. A negative correlation betweenthe total amount of photoassimilate exuded and the calculatedconcentration of PCMBS in the leaf apoplast was also observed.The results indicate that phloem loading in Oncidium Goldianaoccurs via the apoplastic pathway. Key words: Phloem loading, apoplast, PCMBS, tropical orchid  相似文献   

16.
WARCUP  J. H. 《Annals of botany》1951,15(3):305-318
Fructifications of basidiomycetes have been collected at LakenheathWarren, and thirty-nine species have been obtained from fivegrassland soils. The different soils have been found to havedifferent species growing upon them and most species occur onthe alkaline-slightly acid grasslands. Highly acid grasslandat Lakenheath has a poor fungus flora. Studies have been made of the regions in the soil in which themycelia of certain of these basidiomycetes occur, and attemptshave been made to isolate these fungi from soil. Some specieshave been found to inhabit the litter zone rather than the minerallayers of the soil. A few form extensive rhizomorph systemswhich may penetrate deeply into the soil. A few species of ringfungi, such as Marasmius oreades, Psalliota arvensis, and Tricholomanudum, have been found to possess a well-defined mycelial zonein the soil, from which the fungus could be isolated. Profile studies have shown that the mycelial zones of thesespecies contain a restricted population of microfungi, bothfewer species and fewer colonies, as compared with the normalsoil around. Ascomycetes, such as Arachniotus, Chaetomium, Gymnoascus,and Penicillium, have been isolated more frequently from mycelialzones than from normal soil.  相似文献   

17.
We have optimized the genomic DNA extraction method from freshand dry laminas, as well as fresh and dry corolla lobes ofIxoracultivars.Some woody tropical species such as these contain excessiveamounts of phenolic compounds that co-precipitate with DNA resultingin poor or no amplification during the polymerase chain reaction(PCR). Repeated precipitation with CsCl coupled with phenol:chloroformextraction yielded high quality DNA suitable for consistentPCR amplification. The DNA from fresh laminas of 22 cultivarsofIxorawas subjected to random amplified polymorphic DNA (RAPD)analysis. Individual taxa could be identified using specificDNA markers from the RAPD profiles. Cluster analysis of datafrom six primers grouped all 22 cultivars distinctly under twocultivar groups, viz.,IxoraCoccinea andI.Javanica. The percentagegenetic similarity was calculated for all the cultivars basedon the RAPD data. The two cultivar groups and the outgroup plantswere also clearly distinguishable with polar ordination usinga matrix of genetic dissimilarities (one minus similarity).Our data indicate that besides the use of RAPD markers for identificationof particularIxoracultivars within a germplasm collection, thephylogenetic relationships generated by RAPD analysis may beuseful for future breeding programmes. IxoraL. cultivars; Rubiaceae; RAPD fingerprinting; DNA extraction; woody tropical species  相似文献   

18.
Vertical zonation of intertidal organisms, from the shallowsubtidal to the supralittoral zones, is a ubiquitous featureof temperate and tropical rocky shores. Organisms that livehigher on the shore experience larger daily and seasonal fluctuationsin microhabitat conditions, due to their greater exposure toterrestrial conditions during emersion. Comparative analysesof the adaptive linkage between physiological tolerance limitsand vertical distribution are the most powerful when the studyspecies are closely related and occur in discrete vertical zonesthroughout the intertidal range. Here, I summarize work on thephysiological tolerance limits of rocky intertidal zone porcelaincrab species of the genus Petrolisthes to emersion-related heatstress. In the eastern Pacific, Petrolisthes species live throughouttemperate and tropical regions, and are found in discrete verticalintertidal zones in each region. Whole organism thermal tolerancelimits of Petrolisthes species, and thermal limits of heartand nerve function reflect microhabitat conditions. Speciesliving higher in the intertidal zone are more eurythermal thanlow-intertidal congeners, tropical species have the highestthermal limits, and the differences in thermal tolerance betweenlow- and high-intertidal species is greatest for temperate crabs.Acclimation of thermal limits of high-intertidal species isrestricted as compared to low-intertidal species. Thus, becausethermal limits of high-intertidal species are near current habitattemperature maxima, global warming could most strongly impactintertidal species.  相似文献   

19.
For many plant species, growth is limited in acid soils, whichare characterized by high levels of potentially-toxic elementsand low nutrient availability. Although plant-soil interactionsare traditionally studied during the growing season, the highestconcentrations of toxic elements in the soil may occur duringthe winter months. The present study investigated the effectsof a 3-month exposure to either an acid or a reference soil,at temperatures fluctuating around freezing point, on subsequentsurvival and growth of eight herbs (Brachypodium sylvaticum,Carex pilulifera, Geum urbanum, Luzula pilosa, Mycelis muralis,Silene dioica, Stellaria nemorum, Veronica officinalis).Theplants were exposed to ambient weather conditions from Decemberto March, after which they were replanted in fresh referencesoil and transferred to a glasshouse. Their biomass was measured5 weeks later. The plant species differed in their responsesto the soils, in a manner reflecting their natural field distributions.All plants of the most acid-tolerant species survived in bothtreatments, whereas the more sensitive species showed lowersurvival rates after growth in the acid than in the referencesoil. Similar results were found for the regrowth:C. piluliferaandL.pilosa, the most acid-tolerant species, were unaffected by thesoil treatments (ratios between biomass in acid compared toreference soils were 0.8 and 1.1, respectively), whereasG. urbanum,M. muralis, S. nemorumandV. officinaliswere negatively affected(ratios 0.3–0.5). Effects on above- and below-ground biomasswere broadly similar. This preliminary evidence indicates thatsoil chemistry during the winter can be important for both survivaland growth during the vegetative period that follows.Copyright1998 Annals of Botany Company. Acids soils, toxicity, vascular plants, winter exposure.  相似文献   

20.
Root colonization was studied in ten species of the Epacridaceaeat three sites in Victoria by morphological and cross-inoculationexperiments. The sites and genera chosen were Cranbourne [Epacrisimpressa Labill. andLeucopogon ericoides(Smith) R. Br.] andRye [L. parviflorus(Andrews) Lindley] on the Mornington Peninsula,and the Grampians[Astroloma conostephioides(Sond.) Benth.,A.humifusum(Cav.) R. Br.,A pinifolium(R. Br.) Benth,Brachylomadaphnoides(Smith) Benth.,E. impressa, E. impressavar.grandifloraBenth.andStyphelia adscendensR. Br.] in western Victoria. For morphologicalstudies, samples of roots from each species at each site werecleared and stained and examined microscopically. For cross-inoculationstudies, cuttings from each site were struck in potting mediuminoculated with soil from the same and other sites. The ericoidmycorrhizae in the roots of plants found at or grown in Cranbourneand Rye soils were similar. Both were significantly differentfrom the internal hyphae found in the roots of plants foundat or grown in Grampians soils, which were three times largerin diameter and formed dense coils which filled the host celland invaded adjacent epidermal cells. This suggests that morethan one fungus is involved in the relationships, that the MorningtonPeninsula sites had a different fungus from the Grampians siteand that host specificity is low. Vesicular structures werealso found commonly on plants at the Grampians site, in contrastwith other sites. Epacridaceae; root; fungus; mycorrhiza; morphology; inoculation  相似文献   

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