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1.
Cortical oleoresins from 352 Abies magnifica and A. procera trees, collected in 35 localities, were analysed for composition of their monoterpene fractions. The monoterpenes were composed primarily of -pinene, β-pinene, limonene and β-phellandrene, with camphene and 3-carene appearing only sporadically in larger amounts. Limonene, β-phellandrene, -pinene and 3-cerene were used to study the transitional populations in northern California and southern and central Oregon and the transitional-like populations in southern Sierra Nevada. The populations segregated latitudinally into three related clusters—above 44° (A.procera), between 44° and 40° (transitional), and below 40° (A.magnifica). A.magnifica from southern Sierra Nevada and A.magnifica from Mtn. Shasta differed in a number of parameters, with southern Sierra Nevada populations being chemically much closer to typical A. magnifica from central and northern Sierra Nevada. While monoterpene and morphological data did not allow a clear Interpretation of the status of the transitional and southern populations, the paleobotanical evidence favored the recent evolution over introgression. The desirability of additional studies was indicated.  相似文献   

2.
Cortical oleoresin from 351 Abies concolor trees collected in 43 localities was analyzed for composition of its monoterpenoid fraction. The populations could be segregated into three geographic groups: (1) Northern and Central California (equivalent to var. Iowiana), producing camphene and 3-carene in trace to small amounts; (2) Southern California (the Cuyamaca race), producing camphene in trace to small and 3-carene in larger amounts; and (3) states to the east of California (equivalent to var. concolor) producing camphene and 3-carene in larger amounts. California populations from the southernmost Sierra Nevada and Northern Transversal Ranges were found to be chemically intermediate between var. Iowiana and var. concolor. Statistical analysis indicated the presence of additional second-order segregations in each of the four population groups, The results are explained on the basis of existing paleobotanical records.  相似文献   

3.
Knowledge of population genetic structure of tanoak (Lithocarpus densiflorus) is of interest to pathologists seeking natural variation in resistance to sudden oak death disease, to resource managers who need indications of conservation priorities in this species now threatened by the introduced pathogen (Phytophthora ramorum), and to biologists with interests in demographic processes that have shaped plant populations. We investigated population genetic structure using nuclear and chloroplast DNA (cpDNA) and inferred the effects of past population demographic processes and contemporary gene flow. Our cpDNA results revealed a strong pattern of differentiation of four regional groups (coastal California, southern Oregon, Klamath mountains, and Sierra Nevada). The chloroplast haplotype phylogeny suggests relatively deep divergence of Sierra Nevada and Klamath populations from those of coastal California and southern Oregon. A widespread coastal California haplotype may have resulted from multiple refugial sites during the Last Glacial Maximum or from rapid recolonization from few refugia. Analysis of nuclear microsatellites suggests two major groups: (1) central coastal California and (2) Sierra Nevada/Klamath/southern Oregon and an area of admixture in north coastal California. The low level of nuclear differentiation is likely to be due to pollen gene flow among populations during postglacial range expansion.  相似文献   

4.
This morphometric study of the geographic variation in Pinus contorta is based on 93 provenances cultivated in northern Jutland, Hjardemål Klitplantage, 57'04"08'48'E (Arboretum trial no. F275). The numerical methods employed were common principal components analysis (CPCA), non-metric multidimensional scaling (MDSCALE), minimum spanning trees (MST), and the neighbour-joining method (NJOIN). Although it is not always possible to draw a very clear line between the coastal var. contorta and the inland var. latifolia of P. contorta subsp. contorta, these varieties are distinct in their extreme forms. Critical provenances of both varieties seem to originate from the transition zone between the two taxa. The Californian or Sierra Nevada provenances of f contorta subsp. murrayana are very distinct from the Oregon provenances. Apparently most of the inland Oregon provenances of P. contorta are more or less intermediate between var. latifolia and subsp. murmyana s.str. The NJOIN method of phylogenetic reconstruction supports the division of P. contorta into two major groups or subspecies: 1. subsp. contorta, divided into var. contorta and var. latifolia, and 2. subsp. murrayana.  相似文献   

5.
Nineteen composite samples of cortical oleoresin from Pseudotsuga menziesii and P. macorcarpa of different geographic origin were analyzed for the content of their essential oils. A dendrogram derived from this analysis revealed that the populations of P. menziesii from the Sierra Nevada are chemically closer to the inland var. glauca than to the coastal var. menziesii. Sesquiterpenoid hydrocarbons included in the essential oils proved to be chemosystematically as valuable as monoterpenoids in classifying the races.  相似文献   

6.
Wood of Pinus cembroides from 232 trees sampled in 23 localities throughout its range in the United States and Mexico has been analysed for monoterpenes. With a few exceptions the trees of the continental populations from the state of Hidalgo northward produced α-pinene as the main monoterpene. The majority of trees of the southern populations (subsp. orizabensis) from the state of Puebla and adjoining regions of the neighboring Veracruz and Tlaxcala produced 3-carene in appreciable amounts. The population from Baja California (subsp. lagunae) produced monoterpenes of the sabinene family (thujene, sabinene, γ-terpinene, terpinolene and p-cymene) as the main constituents. The variations in morphological characters, including number of needles per fascicle, number of stomatal rows in needles, number of resin canals in needles, as well as other characters of the internal needle morphology, needle length and thickness, needle retention, thickness of seed shells, bark and cone characteristics, rate of growth and cotyledon number either paralleled or did not contradict the chemical variations. The evolution of the southern populations (subsp. orizabensis) into a separate group most likely resulted from geographic separation and climatic differences, while the evolutionary separation of the Baja California trees (subsp. lagunae) was connected with northwestern movement of the California coastal region from Miocene onward and the formation of Sierra Madre Occidental resulting in separation of this population from the mainland populations by the gap of the Gulf of California and the coastal mountain ranges.  相似文献   

7.
The mountain yellow-legged frog Rana muscosa sensu lato , once abundant in the Sierra Nevada of California and Nevada, and the disjunct Transverse Ranges of southern California, has declined precipitously throughout its range, even though most of its habitat is protected. The species is now extinct in Nevada and reduced to tiny remnants in southern California, where as a distinct population segment, it is classified as Endangered. Introduced predators (trout), air pollution and an infectious disease (chytridiomycosis) threaten remaining populations. A Bayesian analysis of 1901 base pairs of mitochondrial DNA confirms the presence of two deeply divergent clades that come into near contact in the Sierra Nevada. Morphological studies of museum specimens and analysis of acoustic data show that the two major mtDNA clades are readily differentiated phenotypically. Accordingly, we recognize two species, Rana sierrae , in the northern and central Sierra Nevada, and R. muscosa , in the southern Sierra Nevada and southern California. Existing data indicate no range overlap. These results have important implications for the conservation of these two species as they illuminate a profound mismatch between the current delineation of the distinct population segments (southern California vs. Sierra Nevada) and actual species boundaries. For example, our study finds that remnant populations of R. muscosa exist in both the southern Sierra Nevada and the mountains of southern California, which may broaden options for management. In addition, despite the fact that only the southern California populations are listed as Endangered, surveys conducted since 1995 at 225 historic (1899–1994) localities from museum collections show that 93.3% ( n =146) of R. sierrae populations and 95.2% ( n =79) of R. muscosa populations are extinct. Evidence presented here underscores the need for revision of protected population status to include both species throughout their ranges.  相似文献   

8.
The phylogeography of the California mountain kingsnake, Lampropeltis zonata, was studied using mitochondrial DNA sequences from specimens belonging to the seven recognized subspecies and collected throughout the range of the species. Maximum parsimony and maximum likelihood methods identified a basal split within L. zonata that corresponds to southern and northern segments of its distribution. The southern clade is composed of populations from southern California (USA) and northern Baja California, Mexico. The northern clade is divided into two subclades, a 'coastal' subclade, consisting of populations from the central coast of California and the southern Sierra Nevada Mountains of eastern California, and a 'northeastern' subclade, mainly comprised of populations north of the San Francisco Bay and from the majority of the Sierra Nevada. We suggest that past inland seaways in southwestern California and the embayment of central California constituted barriers to gene flow that resulted in the two deepest divergences within L. zonata. Throughout its evolutionary history, the northern clade apparently has undergone instances of range contraction, isolation, differentiation, and then expansion and secondary contact. Examination of colour pattern variation in 321 living and preserved specimens indicated that the two main colour pattern characters used to define the subspecies of L. zonata are so variable that they cannot be reliably used to differentiate taxonomic units within this complex, which calls into question the recognition of seven geographical races of this snake.  相似文献   

9.
Expressions of theSalvia dorrii (Kellogg) Abrams complex, a member of subg.Audibertia Benth., are distributed over much of the western United States. The complex consists of two species,S. dorrii andS. pachyphylla Epling ex Munz.Salvia dorrii is divided into subsp.dorrii and subsp.mearnsii (Britton) McClintock, the latter endemic to central Arizona. Subspeciesdorrii is composed of four varieties: var.carnosa (Douglas ex Greene) Cronq., a large-leaved erect shrub of Washington and Idaho southward through Oregon into extreme north-central California: var.dorrii, a small-leaved erect shrub of southern Oregon and Idaho southward through the Great Basin of Nevada and western Utah to southeastern California and northern Arizona: var.pilosa (A. Gray) Strachan & Reveal, a small-leaved erect shrub differing from var.dorrii by pilose bracts and calyx, in southern California and western Arizona with disjunct populations in the Lahontan Basin of northwestern Nevada and northestern California; and var.clokeyi Strachan, var. nov., a low mat-forming subshrub of the high mountains of Clark Co., Nevada.Salvia pachyphylla ranges from southern California southward to the high mountains of Baja California Norte, Mexico, and eastward across extreme southern Nevada to (as a disjunct) northeastern Arizona. Each entity is described in detail, mapped and illustrated.  相似文献   

10.
Dicentra formosa (Haw.) Walp. is morphologically the most variable of the nine North American species in the genus. It constitutes a complex of rhizomatous perennials distributed throughout mountainous regions of the Pacific States. Dicentra nevadensis Eastw. is confined to high elevations in Tulare County, California. Two chromosomal races of Dicentra formosa exist. A tetraploid race, with n = 16, appears to be confined to coastal mountains and valleys, while a diploid race, with n = 8, is distributed along inland mountain ranges, except in Josephine County, Oregon, where the two races could be sympatric. Morphological associations with ploidy level occur, but they appear to be inconstant.  相似文献   

11.
Two new taxa are described from California:Astragalus (sect.Flexuosi)shevockii from the Sierra Nevada in Tulare County representing a new subsect.Shevockiani; andA. lentiginosus var.piscinensis from an alkaline spring in Mono County. Rediscovery in Nevada of long-lostA. lentiginosus var.sesquimetralis and a new station for the same in Inyo County, California are reported.  相似文献   

12.
Atmospheric deposition of nitrogen (N) in California ecosystems is ecologically significant and highly variable, ranging from about 1 to 45 kg/ha/year. The lowest ambient concentrations and deposition values are found in the eastern and northern parts of the Sierra Nevada Mountains and the highest in parts of the San Bernardino and San Gabriel Mountains that are most exposed to the Los Angeles air pollution plume. In the Sierra Nevada Mountains, N is deposited mostly in precipitation, although dry deposition may also provide substantial amounts of N. On the western slopes of the Sierra Nevada, the majority of airborne N is in reduced forms as ammonia (NH3) and particulate ammonium (NH4+) from agricultural activities in the California Central Valley. In southern California, most of the N air pollution is in oxidized forms as nitrogen oxides (NOx), nitric acid (HNO3), and particulate nitrate (NO3-) resulting from fossil fuel combustion and subsequent complex photochemical reactions. In southern California, dry deposition of gases and particles provides most (up to 95%) of the atmospheric N to forests and other ecosystems. In the mixed-conifer forest zone, elevated deposition of N may initially benefit growth of vegetation, but chronic effects may be expressed as deterioration of forest health and sustainability. HNO3 vapor alone has a potential for toxic effects causing damage of foliar surfaces of pines and oaks. In addition, dry deposition of predominantly HNO3 has lead to changes in vegetation composition and contamination of ground- and stream water where terrestrial N loading is high. Long-term, complex interactions between N deposition and other environmental stresses such as elevated ozone (O3), drought, insect infestations, fire suppression, or intensive land management practices may affect water quality and sustainability of California forests and other ecosystems.  相似文献   

13.
Three hundred thirty-three blue grouse (Dendragapus obscurus) were examined for blood parasites from 11 sites: southern Yukon Territory, southeast coastal Alaska, northern and central interior British Columbia, south coastal British Columbia, northcentral Washington, southcentral Oregon, northwestern California, eastcentral Nevada, northwestern Colorado, and westcentral Montana. Three species of protozoan parasites (Leucocytozoon lovati, Haemoproteus mansoni, Trypanosoma avium) and a splendidofilariid nematode (Microfilaria sp. B) were found in nearly all locations. Prevalence levels were consistently high for L. lovati (92%). The other hematozoa were found less frequently (H. mansoni 29%; T. avium 46%; and microfilaria 29%). The range of these parasites in blue grouse was extended to a more northern (Yukon Territory) and more southern distribution (Nevada than previously reported. Ranges were also extended to blue grouse populations in Alaska, Washington, Oregon and California.  相似文献   

14.
Quantitative variation in monoterpenes in four species of conifers   总被引:6,自引:0,他引:6  
Eighteen monoterpenes found in bole and foliage volatiles of four sympatric species of conifers, Douglas-fir, Pseudotsuga menziesii (Mirb.) Franco, lodgepole pine, Pinus contorta var. latifolia Engelm., interior spruce, Picea engelmannii×glauca, and interior fir, Abies lasiocarpa×bifolia, in three locations in British Columbia, Canada, were analysed for quantitative variation (N=10 trees per sample) using standard and chiral gas chromatography. There was significant variation in monoterpene composition between bole and foliage in all four species. Principal components analysis revealed that the monoterpene profile of coastal Douglas-fir was significantly different from trees in the interior, supporting the hypothesis that coastal and interior populations represent distinct chemotypes. Although the four species did not differ qualitatively, there were significant differences in their quantitative monoterpene profiles in both bole and foliage. These differences were large enough to suggest that host selection by four species of coniferophagous bark beetles (Coleoptera: Scolytidae), specific to each of the above tree species, may depend in part on perception of, and behavioural response to quantitatively distinct blends of monoterpenes.  相似文献   

15.
Analysis of 12 microsatellite loci from431 mountain lions (Puma concolor)revealed distinct genetic subdivision that wasassociated with geographic barriers andisolation by distance in California. Levels ofgenetic variation differed among geographicregions, and mountain lions that inhabitedcoastal areas exhibited less heterozygositythan those sampled inland. The San FranciscoBay and Sacramento-San Joaquin River Delta, theCentral Valley, and the Los Angeles Basinappeared to be substantial barriers to geneflow, and allele frequencies of populationsseparated by those features differedsubstantially. A partial barrier to gene flowappeared to exist along the crest of the SierraNevada. Estimated gene flow was high amongmountain lions inhabiting the Modoc Plateau,the western Sierra Nevada, and northern sectionof the eastern Sierra Nevada. SouthernCalifornia mountain lion populations mayfunction as a metapopulation; however, humandevelopments threaten to eliminate habitat andmovement corridors. While north-south geneflow along the western Sierra Nevada wasestimated to be very high, projected loss andfragmentation of foothill habitat may reducegene flow and subdivide populations. Preservation of existing movement corridorsamong regions could prevent population declinesand loss of genetic variation. This studyshows that mountain lion management andconservation efforts should be individualizedaccording to region and incorporatelandscape-level considerations to protecthabitat connectivity.  相似文献   

16.
The essential oil composition of 68 individual plants of Juniperus phoenicea from Portugal was investigated by GC, GC-MS and 13C NMR. -Pinene, β-phellandrene, -terpinyl acetate and myrcene were found to be the main constituents. Botanical and chemical data as well as phytogeographical distribution indicate J. phoenicea var. turbinata as the unique subspecies occurring in Portugal. Nevertheless, this taxon exhibits chemical polymorphism. The results of the oil compositions were processed by hierarchical clustering and principal component analysis allowing to establish three groups of essential oils differentiated by the content of -pinene, β-phellandrene and -terpinyl acetate.  相似文献   

17.
Communities of archaea, bacteria, and fungi were examined in forest soils located in the Oregon Coast Range and the inland Cascade Mountains. Soils from replicated plots of Douglas-fir (Pseudotsuga menziesii) and red alder (Alnus rubra) were characterized using fungal ITS (internal transcribed spacer region), eubacterial 16S rRNA, and archaeal 16S rRNA primers. Population size was measured with quantitative (Q)-PCR and composition was examined using length heterogeneity (LH)-PCR for fungal composition, terminal restriction fragment length (T-RFLP) profiles for bacterial and archaeal composition, and sequencing to identify dominant community members. Whereas fungal and archaeal composition varied between sites and dominant tree species, bacterial communities only varied between sites. The abundance of archaeal gene copy numbers was found to be greater in coastal compared to montane soils accounting for 11% of the prokaryotic community. Crenarchaea groups 1.1a-associated, 1.1b, 1.1c, and 1.1c-associated were putatively identified. A greater abundance of Crenarchaea 1.1b indicator fragments was found in acidic (pH 4) soils with low C:N ratios under red alder. In coastal soils, 25% of fungal sequences were putatively identified as basidiomycetous yeasts belonging to the genus Cryptococcus. Although the function of these yeasts in soil is not known, they could significantly contribute to decomposition processes in coastal soils distinguished by rapid tree growth, high N content, low pH, and frequent water-saturation events.  相似文献   

18.
ABSTRACT Delineating a species' geographic range using the spatial distribution of museum specimens or even contemporary detection-non-detection data can be difficult. This is particularly true at the periphery of a species range where species' distributions are often disjunct. Wolverines (Gulo gulo) are wide-ranging mammals with discontinuous and potentially isolated populations at the periphery of their range. One potentially disjunct population occurred in the Sierra Nevada Mountains, California, USA, and appears to have been extirpated by the 1930s. Many early 20th century naturalists believed that this population was connected to other populations occurring in the Cascade Range of northern California, Oregon, and Washington, USA, but a recent analysis of historical records suggests that California wolverines were isolated from other populations in North America. We used DNA extracted from museum specimens to examine whether California wolverines were isolated. Both nuclear and mitochondrial DNA data indicate that California wolverines were genetically distinct from extant populations, suggesting long-term isolation. We identified 2 new control region (mitochondrial DNA) haplotypes located only within California. We used these data and referenced sequences from the Rocky Mountains, USA, to make inferences regarding potential wolverine translocations into California. In addition, we used these genetic data to make inferences about wolverine conservation throughout western North America.  相似文献   

19.
Whether intentionally or accidentally introduced, exotic species have the capacity to dramatically disrupt native communities. In central California, tiger salamanders (Ambystoma tigrinum) have been introduced as a by-product of the sport fishing bait industry. Some of these introductions are relatively well known and have resulted in the formation of hybrids with the imperiled native California tiger salamander (A. californiense). Other populations of A. tigrinum, particularly in the northern and eastern parts of the state, remain poorly characterized and are present in regions where relictual amphibian populations of other species have persisted, suggesting that these might be relictual, native A. tigrinum. We used genetic sequence data to determine the provenance of all known extralimital A. tigrinum populations in California and adjacent Oregon and Nevada through comparison with reference samples from the native range of A. tigrinum. Our results suggest that A. tigrinum have been introduced in Northern California, Southern California and the Sierra Nevada, originating from multiple sources across the Great Plains of the US. Furthermore, two populations near the California-Oregon border are most closely related to A. tigrinum populations from Washington and Oregon and may represent native tiger salamander lineages.  相似文献   

20.
Sabinene and γ-terpinene were assayed in vitro acting singly or in mixtures in the gaseous state on the following redwood endophytes: Botrytis cinerea, Cryptosporiopsis abietina, Pestalotiopsis funerea, Phomopsis occulta, Pleuroplaconema sp. and Seiridium juniperi. The hypothesis that these redwood monoterpenes were acting additively or synergistically in inhibiting the growth on leaf endophytes was tested. Dose-response curves were obtained for each endophyte growing under five concentrations of both sabinene and γ-terpinene. Three mixtures of different ratios were assayed keeping constant 0.25 mg of monoterpenes per ml air. Either acting singly or in mixtures sabinene and γ-terpinene were inhibitory to all fungi, but their effect varied according to species. Both compounds had similar effects acting singly on each endophyte with doses from 0.0625 to 0.25 mg ml air−1. With doses of 1.6667 mg ml air−1 of either monoterpene, S. juniperi was mildly inhibited by sabinene and strongly inhibited by γ-terpinene, but other species were strongly and equally inhibited by both compounds. Sabinene: γ-terpinene mixtures of 1:3, 1:1 and 3:1 ratios were equally inhibitory for each species. Results suggest that when these compounds co-occur, they act additively on leaf endophytic fungi.  相似文献   

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