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1.
Agrostis species have been known to evolve ecotypes rapidly in response to unusual edaphic conditions. The geographic distribution of Agrostis taxa in Lassen Volcanic National Park (California) and Yellowstone National Park (Wyoming) in the United States and the Valley of the Geysers (Kamchatka Peninsula) in Russia suggests that Agrostis scabra might have independently evolved morphologically similar ecotypes several times. We used RAPDs to show that, contrary to expectation, the thermal populations are not independently evolved, but instead constitute a single taxon that currently has four names. A UPGMA including the four thermal and nine nonthermal Agrostis taxa showed that the thermal cluster divides into geographically distinct subclusters, but that two morphologically distinct thermal taxa do not cluster independently. Even though currently confused with the thermal populations, nonthermal A. scabra is not closely related. An analysis of molecular variance (AMOVA) showed significant differentiation between the thermal populations and the nonthermal species sampled in this study. Splitting a hypothesized thermal operational taxonomic unit (OTU) into its components (geographically separated populations) does not greatly affect the partitioning of variation among OTUs. All thermal populations therefore should be assigned to the same taxon, but its taxonomic rank cannot be determined at this time.  相似文献   

2.
The foliage of 80 species common in the Santa Rosa National Park, Costa Rica, has been analysed for content of total phenolics, condensed tannins, acid detergent fibre and water. Wherever possible analyses were performed at three stages in the life cycle of the leaf: young but fully expanded (coinciding with the beginning of the rainy season); middle-aged (two months later); and old (six months later). A comparison of the three age classes showed no significant change in the levels of phenolics or fibre as leaves aged but water content decreased significantly. A comparison of deciduous and evergreen species in the sample showed that the latter group had leaves with a significantly higher fibre content at all three sampling times, most particularly at the beginning of the rainy season, but other measures were not significantly different. Alkaloids were much more common in the foliage of deciduous species and it was observed that their distribution differed significantly from that of total phenolics and condensed tannins. It is suggested that the interaction that occurs between many tannins and alkaloids would be liable to reduce the defence capability of both classes of compounds if they occurred together.
High levels of defoliation occur in the early rainy season (third to tenth weeks) due to larvae of moths of the Sphingidae and Saturniidae. A comparison of investigated tree species that host larvae of these two taxa shows a striking dichotomy. Species that are selected by Sphingidae tend to be relatively deficient in levels of phenolics but are more likely to contain alkaloids, and probably other small toxic molecules. Saturniidae, on the other hand, appear to prefer host-species rich in phenolics but poor in alkaloids.  相似文献   

3.
Pectiniunguis bollmani n. sp. (Chilopoda: Geophilomorpha: Schendylidae) is described from the Morrocoy National Park (State of Falc¢n, Venezuela) and considered as very closely related to P. halirrhytus Crabill, 1959. Additional data on P. halirrhytus Crabill and comments on the geographical distribution of the two taxa, both probably halophilous, are also given.  相似文献   

4.
为了解三江源国家公园野生兽类的分布现状,2015-2017年对园区进行了实地调查。根据调查结果并参考相关文献资料,三江源国家公园内野生兽类共62种,分别隶属8目19科44属。园区内兽类呈现出物种多样性高,珍稀濒危物种多,特有种多的特点:三江源国家公园内的兽类物种多样性G-F指数为0.77,表明该区域物种多样性处于很高水平。根据中国物种红色名录,20个物种受威胁(极危、濒危和易危),比例为32.26%,远高于国家整体水平;中国或青藏高原特有种29种,占46.77%。三江源国家公园在动物地理区划上属于古北界青藏区,在地理分布型上,以古北界成分为主,东洋界成分为辅,以古北界高山型成分最多,有25种,且资源量大,表明三江源国家公园的兽类以适应高寒气候的特殊种类为主。3个园区的平均动物区系相似性比较结果表明,长江源园区与澜沧江源园区为共同关系,黄河源园区与长江源园区和澜沧江源园区为密切关系。近些年,三江源地区的兽类保护工作取得了很好的效果,并得到国内外认可,本研究结合园区生物多样性和区系特点,根据保护现状,提出了今后的监测保护建议。  相似文献   

5.
Fourteen nuclear microsatellite loci were isolated from a genomic DNA library derived from a free‐ranging bamboo lemur (Hapalemur griseus griseus) from Ranomafana National Park, Madagascar. Expected and observed heterozygosity levels were determined for populations of bamboo lemurs from Ranomafana National Park and a nonprotected area near Tsinjoarivo, Madagascar. Although genotype frequencies for all but one marker were within Hardy–Weinberg expectations for the Tsinjoarivo population, this was not the case for the Ranomafana samples. It is probable that the deviation of genotype frequencies from Hardy–Weinberg expectations in Ranomafana was precipitated by the presence of two taxa within the sample population.  相似文献   

6.
The chemical investigation of the aerial parts of Guatteria ferruginea collected in the National Park of Serra dos Órgãos, Teresópolis, Brazil and of Guatteria latifolia and Guatteria sellowiana collected in the National Park of Itatiaia, Itatiaia, Brazil resulted in the isolation and identification of six isoquinoline alkaloids, two aporphine alkaloids 3-hydroxy-nornuciferine (1), nornuciferine (2) and four oxoaporphine alkaloids lysicamine (3), isomoschatoline (4), liriodenine (5) and O-methylmoschatoline (6). The isoquinoline alkaloids were found in the species G. ferruginea, G. latifolia and G. sellowiana for the first time and they support the taxonomic position within the genus Guatteria. Isoquinoline alkaloids (5–6) can be considered chemotaxonomic markers of the subfamily Annonoideae.  相似文献   

7.
Habitat diversity (spatial heterogeneity within and between habitat patches in a landscape, HD) is often invoked as a driver of species diversity at small spatial scales. However, the effect of HD on species richness (SR) of multiple taxa is not well understood. We quantified HD and SR in a wet-dry gradient of open grassland habitats in Hortobágy National Park (E-Hungary) and tested the effect of compositional and structural factors of HD on SR of flowering plants, orthopterans, true bugs, spiders, ground beetles and birds. Our dataset on 434 grassland species (170 plants, 264 animals) showed that the wet-dry gradient (compositional HD at the between-patch scale) was primarily related to SR in orthopterans, ground-dwelling arthropods, and all animals combined. The patchiness, or plant association richness, of the vegetation (compositional HD at the within-patch scale) was related to SR of vegetation-dwelling arthropods, whereas vegetation height (structural HD at the within-patch scale) was related to SR of ground-dwelling arthropods and birds. Patch area was related to SR only in birds, whereas management (grazing, mowing, none) was related to SR of plants and true bugs. All relationships between HD and SR were positive, indicating increasing SR with increasing HD. However, total SR was not related to HD because different taxa showed similar positive responses to different HD variables. Our findings, therefore, show that even though HD positively influences SR in a wide range of grassland taxa, each taxon responds to different compositional or structural measures of HD, resulting in the lack of a consistent relationship between HD and SR when taxon responses are pooled. The idiosyncratic responses shown here exemplify the difficulties in detecting general HD-SR relationships over multiple taxa. Our results also suggest that management and restoration aimed specifically to sustain or increase the diversity of habitats are required to conserve biodiversity in complex landscapes.  相似文献   

8.
A study on the microarthropod community with special reference to species diversity of Oribatid and Collembola communities (Microarthropoda: Oribatei and Collembola) in Tam Dao National Park of Vietnam, a subtropical evergreen broad leaf alpine forest, was undertaken with the aim to explain how they are related to forest decline, and whether they can be used as bioindicators of forest plant succession. The results have shown that microarthropod community structures, particularly species diversity of oribatid and collembolan communities, are related to forest decline. Therefore they can be used as bioindicators of forest plant succession. In Tam Dao National Park, there was an inverse relation between species diversity of the oribatid and collembola communities. The species diversity of the oribatid community gradually decreased with forest decline whereas the species diversity of the collembola community gradually increased.  相似文献   

9.
Preliminary observations on chironomid assemblages in 9 temporary pools of the National Park of Circeo (Central Italy) are reported. A total of 15 genera or species groups (6 Orthocladiinae, 3 Tanypodinae, 1 Tanytarsini and 5 Chironomini) were recorded during March and April, 1986.Psectrotanypus varius, Polypedilum nubeculosum gr.,Chironomus thummi gr. andC. plumosus gr. were the most abundant and frequent taxa in the nine pools. Almost all chironomids collected are eurytopic and widely distributed in Europe, including Italian waters. Only the finding ofGymnometriocnemus is reported in this paper as a new record for Central Italy. Similarity among pools and among taxa (coefficient of Jaccard) shows a major occurrence of aquatic Orthocladiinae in smaller pools and of Chironomini in larger pools. This relationship between chironomid assemblages and pool sizes can be partly related to the duration of the wet phase which affects chironomid species according to their survival strategies.  相似文献   

10.

Background

Plant invasions are causing habitat degradation in Galapagos. Problems are concentrated on the four inhabited islands. Plants introduced to rural areas in the humid highlands and urban areas on the arid coast act as foci for invasion of the surrounding Galapagos National Park.

Methodology/Principal Findings

Here we present results of the most comprehensive inventory to date of alien vascular plants in the inhabited areas of Galapagos. The survey was conducted between 2002 and 2007, in 6031 properties (97% of the total) on Floreana, Isabela, San Cristobal and Santa Cruz Islands. In total 754 alien vascular plant taxa were recorded, representing 468 genera in 123 families. Dicotyledons represented 554 taxa, monocotyledons 183, there were 7 gymnosperms and 10 pteridophytes. Almost half (363) of the taxa were herbaceous. The most represented families were Fabaceae (sensu lato), Asteraceae and Poaceae. The three most recorded species in the humid rural areas were Psidium guajava, Passiflora edulis and Bryophyllum pinnatum, and in the dry urban areas, Aloe vera, Portulaca oleracea and Carica papaya. In total, 264 (35%) taxa were recorded as naturalized. The most common use for taxa was ornamental (52%).

Conclusions/Significance

This extensive survey has increased the known alien vascular flora of Galapagos by 257 species, giving a ratio of alien to native taxa of 1.57∶1. It provides a crucial baseline for plant invasion management in the archipelago and contributes data for meta analyses of invasion processes worldwide. A repeat of the survey in the future would act as an effective early detection tool to help avoid further invasion of the Galapagos National Park.  相似文献   

11.
The occurrence and distribution of tropane and biogenetically related pyrrolidine alkaloids in 18 Merremia species of paleo-, neo-, and pantropical occurrence have been studied. The extensive GC-MS study included members of almost all sections of the genus and has been carried out with epigeal vegetative parts as well as with roots. It comprises altogether 74 tropanes and 13 pyrrolidines including nicotine. Along with datumetine known already from a solanaceous species, the study led to the isolation (from M. dissecta and M. guerichii, respectively) and structure elucidation (spectral data) of four novel 3alpha-acyloxytropanes, merresectines A-D: 3alpha-(4-methoxybenzoyloxy)nortropane (A), 3alpha-kurameroyloxytropane (B), 3alpha-nervogenoyloxytropane (C), 3alpha-[4-(beta-D-glucopyranosyloxy)-3-methoxy-5-(3-methyl-2-butenyl)benzoyloxy]tropane (beta-d-glucoside of D). Moreover, the novel 3alpha,6beta-di-(4-methoxybenzoyloxy)tropane (merredissine) has been isolated from M. dissecta and structurally elucidated. In addition the structures of datumetine and merresectine A could be confirmed by synthesis. Spectral data for two known 3alpha-acyloxytropanes (merresectine E beta-D-glucoside, 4'-dihydroconsabatine) and one known 3beta-acyloxytropane (concneorine) are documented for the first time. The structures of three further merresectines (F-H) have been determined by mass spectrometry. Furthermore, the linkage (2',3- and 2',4-, respectively) of two position isomer N-methylpyrrolidinylhygrines was proven by synthesis. The results of the study contribute to the solution of infrageneric taxonomic problems. Whereas all species yield pyrrolidine alkaloids without suitably differentiating results the diverging occurrence of tropane alkaloids leads to three groups of sections: (1) taxa free of tropanes, (2) taxa with simple tropanes, and (3) taxa with merresectines in addition to simple tropanes.  相似文献   

12.
中国三江源国家公园与韩国智异山国家公园的对比研究   总被引:1,自引:0,他引:1  
自1967年智异山被认定为韩国首个国家公园以来,韩国以国家公园为主体的自然保护地体系建设已历经50余年。这期间韩国在国家公园的建设中积累了大量经验,十分值得我国借鉴。选取我国首个国家公园体制试点——三江源国家公园和韩国首个国家公园——智异山国家公园为研究对象,对二者的管理现状进行了定性分析,并运用基于最优实践的国家公园管理能力评价方法对二者的管理能力进行了定量评价。研究表明:三江源国家公园的管理能力综合得分低于智异山国家公园,在体制建设、保障机制、资源环境管理、社区管理和科普教育五个方面均与智异山国家公园存在一定差距;智异山国家公园在资源本底调查、法制建设、多方参与、环境教育和游憩管理方面的管理能力十分突出,为三江源国家公园管理能力的提升提供了有益借鉴;三江源国家公园在生态补偿和制度约束方面具有比较优势,但在自然资源权属、资源本底调查、社区组织建设和游憩管理方面则亟待提升。在此基础上,针对三江源国家公园建设提出了强化科研支撑、健全多方参与制度、推进全民福利共享三项建议,针对我国国家公园体制建设提出了制定《国家公园法》、设置自然保护地顶层规划两项建议,以期促进三江源国家公园管理能力提升、推动我国国家公园体制建设。  相似文献   

13.
In this study, the bryophyte flora of ??neada Floodplain Forest National Park (K?rklareli-Demirköy) and Acarlar Floodplain Forest (Sakarya-Karasu) in Turkey were investigated in 2016–2017. Here, we report Bryum gemmiferum R. Wilczek & Demaret from ??neada Floodplain Forest National Park in Turkey. In addition, we report Atrichum crispum (James) Sull from both ??neada and Acarlar Floodplain Forest in Turkey. Atrichum crispum is also a new record for Asia continent. Illustrations, location in Turkey and comparisons with morphologically similar taxa were given.  相似文献   

14.
三江源国家公园鸟类物种多样性研究   总被引:5,自引:0,他引:5  
三江源国家公园位于青藏高原腹地,是生物多样性最为集中的区域。为了系统掌握公园内的鸟类分布状况,2015—2017年,对三江源国家公园区域进行了长期的野外调查,结合文献资料,发现三江源国家公园内共分布野生鸟类196种,隶属于18目45科121属。各级保护鸟类59种,占公园鸟类总数的30.1%,其中,国家I级重点保护鸟类8种;国家II级重点保护鸟类27种;青海省级保护鸟类24种。另外,还有国家三有鸟类120种。根据中国物种红色名录,受威胁(濒危、易危和近危)物种有39种,占公园鸟类总数的19.9%。中国特有鸟类15种,占园区内鸟类总数的7.65%。在地理分布型上,三江源国家公园位于古北界青藏区,古北界物种有145种;东洋界物种有37种;广布种有14种。利用G-F指数对物种多样性进行评估,三江源国家公园鸟类的G-F指数为0.825,表明公园内的鸟类物种多样性处于较高水平。长江源园区、澜沧江源园区和黄河源园区的平均动物区系相似性结果表明,三个园区之间动物区系关系均为密切关系。三江源国家公园鸟类物种多样性高、特有种及珍稀濒危物种丰富,具有极高的保护价值和意义。  相似文献   

15.
Drought mortality of bush elephants in Hwange National Park, Zimbabwe   总被引:2,自引:1,他引:1  
African bush elephants inhabiting the undeveloped Kalahari Sands region of Hwange National Park, Zimbabwe are subject to episodic mortality during droughts. We monitored the drought‐related mortality of elephants in Hwange National Park over the course of an extended drought between 1993 and 1995. The drought‐related mortality of elephants was higher during 1994 than 1995, despite significantly higher rainfall in 1994 than 1995. We found significant differences in the age‐specific mortality of elephants during 1994 and 1995. The cumulative mortality profile from this study differed significantly from previous die‐offs at this site, with a higher mortality among adult age classes than that reported from earlier studies in Hwange National Park. The effective duration of the rainy season, not total annual precipitation, appears to be the best predictor for the potential severity of drought mortality among elephants in the Kalahari Sands habitats of Hwange National Park.  相似文献   

16.
Tian M  Deuve T  Felix R 《ZooKeys》2012,(164):51-90
The carabid genus Orthogonius MacLeay is treated, based mainly on materials collected in Thailand through the TIGER project (the Thailand Inventory Group for Entomological Research). Among 290 specimens, 20 species are identified in total, 10 of them are new species: Orthogonius taghavianaesp. n. (Nakhon Nayok: Khao Yai National Park), Orthogonius coomanioidessp. n. (Phetchabun: Thung Salaeng Luang National Park), Orthogonius similarissp. n. (Phetchabun: Thung Salaeng Luang National Park; Loei: Phu Kradueng National Park), Orthogonius setosopalpigersp. n. (Phetchabun: Thung Salaeng Luang National Park), Orthogonius gracililamellasp. n. (Loei: Phu Kradueng National Park; Chaiyaphum: Tat Tone National Park), Orthogonius pseudochaudoirisp. n. (Phetchabum: Thung Salaeng Luang National Park; Nakhon Nayok: Khao Yai National Park), Orthogonius constrictussp. n. (Phetchabum: Thung Salaeng Luang National Park), Orthogonius pinophilussp. n. (Phetchabum: Thung Salaeng Luang National Park), Orthogonius varisp. n. (Cambodia: Siem Reap; Thailand: Ubon Ratchathani: Pha Taem National Park; Phetchabun: Thung Salaeng Luang National Park) and Orthogonius variabilissp. n. (Thailand: Phetchabun: Thung Salaeng Luang National Park; Nakhon Nayok: Khao Yai National Park; Phetchabun: Nam Nao National Park; China: Yunnan). In addition, Orthogonius mouhoti Chaudoir, 1871 and Orthogonius kirirom Tian & Deuve, 2008 are recorded in Thailand for the first time. In total, 30 species of Orthogonius have been recorded from Thailand, indicating that Thailand holds one of the richest Orthogonius faunas in the world. A provisional key to all Thai species is provided. A majority of Thai Orthogonius species are endemic. Among the ten national parks in which orthogonine beetles were collected, Thung Salaeng Luang holds the richest fauna, including 16 species.  相似文献   

17.
1. Benthic macroinvertebrate community and habitat features varying at the microscale ( 0.09 m 2 ) were measured on one sampling occasion in the Thredbo River, Kosciusko National Park, NSW, Australia.
2. Most of the substratum habitat variables were measured in three dimensions using stereo photography. This is the first time that this method has been used so extensively for this purpose in freshwater ecology.
3. Microhabitat variables most related to benthic macroinvertebrate distribution and abundance were selected with multivariate analyses included rock length, height, area and water velocity. Individual variables alone could not account for macroinvertebrate variation, indicating the importance of interactions among variables.
4. Nine selected habitat variables were used to predict macroinvertebrate taxonomic content of additional sites. Predictions were 87% accurate for taxa with a > 50% chance of occurrence and 93% accuracy for taxa with a > 70% chance of occurrence. Variability observed in macroinvertebrate assemblages at the time of sampling was largely physically controlled and highly deterministic.  相似文献   

18.
The diversity of Scenedesmus and Scenedesmus -like taxa from Itasca State Park, Minnesota was assessed using light microscopy and molecular techniques. Thirty isolates from various ponds and lakes in Itasca State Park were examined. Light microscopy showed many similarities in morphology among isolates, but PCR-RFLP analysis of the ribosomal ITS region from these isolates revealed twenty different types. A previous study from Itasca State Park using only light microscopy found only six taxa of Scenedesmus ; however, our results suggest that there is much greater diversity than previously suspected. DNA sequences of the 5.8S ribosomal subunit and the ITS-2 region from our isolates are presently being determined and will be used to assess this diversity in greater detail.  相似文献   

19.
Endophytic fungi were isolated from the stems, petioles, midribs, and leaves of seedlings of six native tree species collected from Doi Suthep-Pui National Park, Thailand. Endophytes were isolated from all tissue samples investigated, and taxa included five ascomycetes, eight anamorphic taxa, and numerous sterile mycelia. Twenty-six strains were tested for their ability to produce cellulase, mannanase, proteinase, and xylanase. The ability to produce these enzymes was distributed amongst the strains tested. Rainforest seedlings supported a diverse array of endophytes that have a wide range of enzymatic activities. The implication of enzyme production in relation to lifestyle abilities of the endophytes is discussed.  相似文献   

20.
A partial skeleton of the aetosaurParatypothorax andressi from Petrified Forest National Park, Arizona, is the first documentation of this species in North America.Paratypothorax is one of the few tetrapod taxa that occur in both the Keuper of Germany and the Chinle Group of the western United States, but it is of limited biochronological utility, because it occurs in strata that range in age from late Carnian to middle Norian.  相似文献   

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