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1.
Abstract: If individuals can be identified from patterns in their footprints, noninvasive survey methods can be used to estimate abundance. Track plates capture fine detail in the footprints of fishers (Martes pennanti), recording rows of dots corresponding to tiny papillae on the animal's metacarpal pad. We show that the pattern of these dots can be used to identify individual fishers, similar to human fingerprints. A probabilistic model of uniqueness based on variation in spacing between 1,400 pairs of dots that we measured in prints of 14 different fisher feet suggests the probability of encountering a similar pattern in the print of a different foot by chance alone is ≤ 0.35n, where n = the number of dot pairs examined. This predicts a 0.00003 probability that a match made using 10 pairs of dots is false. Dot spacing from footprints made by the same foot was remarkably consistent (sN = 0.02 mm, n = 24 dot pairs). Combined, these results suggest dot patterns in fisher footprints were unique to individuals and were consistently reproduced on track plates. Empirical tests of matching accuracy were best with good-quality prints, highlighting the need for experience judging when prints are usable. We applied print matching to fisher detections collected on track plates deployed at 500-m intervals along 10 3.5-km transects in the Adirondack region of New York, USA. Of 62 fisher detections, 85% had ≥ 1 footprint of suitable quality to compare with other high-quality prints. We found that most detections from a transect were from the same individual fisher suggesting nonindependence of detections. Thus, data from traditional track-plate deployments over small time periods cannot be used as a measure of abundance, but new study designs using print matching could obtain robust noninvasive, mark—recapture density estimates.  相似文献   

2.
Eighty eight autopsy specimens obtained from 30 fetuses, still-borns and infants died during the first year of life, all suspected for congenital virus infection at postmortem examination, were studied. The specimens were analyzed by 3 techniques: rapid culture method (RCM) for detection of cytomegalovirus (CMV) infectious activity, the immunocytochemical method for detection of CMV antigen in prints of organs and polymerase chain reaction (PCR) for detection CMV DNA. CMV was detected in 16 out of 26 specimens (61.5%) by PCR, in 43 out of 88 specimens (49%) by RCM and in 15 out of 64 specimens (23%) in prints. The comparison of immune reagents revealed that monoclonal antibodies (McAb) were more specific than polyclonal serum antibodies, as the latter yielded the positive reaction in 10 out of 26 cases (38%), found to be negative in PCR. The data thus obtained indicate that complex techniques, including PCR and RCM in combination with McAb, should be used for evaluation of CMV infection role in child mortality.  相似文献   

3.
Spatial patterns of photobiont diversity in some Nostoc-containing lichens   总被引:3,自引:3,他引:0  
Patterns of photobiont diversity were examined in some Nostoc -containing lichens using the nucleotide sequence of the cyanobacterial tRNALeu (UAA) intron. Lichen specimens collected in northwestern USA were analysed and the sequence data were compared with tRNALeu(UAA) intron sequences previously obtained from lichens in northern Europe. Generally, it is the species identity of a lichen rather than the geographical origin of the specimen that determines the identity of the cyanobiont. Identical intron sequences were found in Peltigera membranacea specimens collected in Oregon (USA) and in Sweden, and very similar sequences were also found in Nephroma resupinatum thalli collected in Oregon and Finland. Furthermore, in mixed assemblages where two Peltigera species grew in physical contact with each other, the different lichen species housed different photobiont strains. There is however not a one-to-one relation between mycobiont and photobiont as some intron sequences were found in more than one lichen species, and different intron sequences were found in different samples of some lichen taxa. Peltigera venosa exhibited a higher level of photobiont diversity than any other lichen species studied, and several intron sequences could for the first time be obtained from a single thallus. It is not clear whether this is evidence of lower cyanobiont specificity, or reflects an ability to exhibit different degrees of lichenization with different Nostoc strains. In one specimen of P. venosa , which contained bipartite cyanosymbiodemes and tripartite, cephalodiate thalli, both thallus types contained the same intron sequence.  相似文献   

4.
A molecular study was undertaken to clarify the identity of the photobiont in colourmorphs of the lichen,Peltigera membranaceaTwo strains of cyanobacteria, identified asNostocsp. by morphology, were cultivated from each of two lichen specimens. Prokaryotic (16S) ribosomal RNA gene fragments were amplified by the polymerase chain reaction (PCR) from DNA extracted from the isolated strains and the lichens, and sequenced directly. Sequences were 98·1% identical between lichen specimens, TDI#AR94 and TDI#AR95, and highly similar to sequences published, or generated in this study from a type culture, forNostocThe 16S ribosomal RNA gene sequences (‘ 16S rDNA ’) of all four lichen-derived cyanobacteria appeared the same, even though the lichen specimens from which they originated had different sequences. The 16S rDNA from strains 9A and 9B were different from that of specimen TDI#AR94, the thallus from which they were isolated, and instead were the same as that of strains 10A and 10B, and their source, specimen TDI#AR95. When primers selective for the strain 9A sequence were used, however, a small amount of PCR product corresponding to the 16S rDNA of strain 9A was obtained from lichen TDI#AR94. The results confirm that the photobionts ofP. membranaceabelong toNostocand suggest that genetic differences in the photobiont may be a factor in the occurrence of colourmorphs among cyanolichens.  相似文献   

5.
Piospheres, that is, zones of attenuating stocking impact extending out from watering places, are a feature of arid pastoral regions. The present authors studied, for the first time, the initial development of a piosphere in respect of a number of variables of the soil surface. The site was near-pristine chenopod shrubland, part of a paddock of 1340 ha near Whyalla, South Australia, stocked with ca. 200 sheep on a new watering point. Soil features monitored over the first 2.5 years were dung deposition, sheep track development and surface erosion, the soil lichen crust, compaction of the soil surface and dustfall, using fenced plots of at least 550 m2 as controls. Piosphere patterns (i.e. patterns reflecting the concentricity of stocking pressure around water) were manifest within the first 3 months for sheep dung deposition, sheep track development, and lichen cover. Soil compaction, which was confined to sheep tracks and then largely to the surface 5 cm, displayed a piosphere pattern when it was first recorded 6 months after stocking. Bulk density of this layer was elevated by up to 20%. There was only a weak piosphere pattern in dustfall. The piosphere patterns in sheep track development and destruction of the lichen crust became more pronounced in time. Track direction was near radial. After 2 years the limit of the piosphere pattern ranged from ca. 10 m from the trough for infiltration into dry soil after an abrupt rainstorm, to greater than 800 m for sheep track intensity. These changes occurred at stocking levels amongst the lowest in Australian arid zone pastoral situations. After the first 9 months of sheep stocking there was no discernible effect of grazing on the density of the short-lived grasses or on the pattern of kangaroo arid rabbit activity as judged by the pattern of their dung deposition. No discernible erosion of the soil surface other than in sheep tracks occurred during the first 2 years.  相似文献   

6.
邓红  魏江春 《菌物研究》2007,5(1):55-58
详细论述了地衣标本的采集、制作和保存方法及注意事项,同时阐明了在采集标本的同时进行共生菌和光合共生物分离培养的重要性。  相似文献   

7.
An exhumed late Pleistocene land surface on the deltaic Sandai Plain north of Lake Bogoria, Kenya, preserves traces of bovids, suids, birds, and at least one hominid. The host sediments (Loboi Silts) are reddish brown, poorly bedded siltstones, mudstones and silty sandstones that were probably deposited in a shallow closed-basin lake. Most of the prints were impressed on exposed, moist lake-marginal mudflats. Print distribution is patchy due to a complex interaction between biogenic and sedimentological factors. The preservation of a single hominid track provides a fortuitous addition to the sparse hominid track record in East Africa. Field, petrographic, and mineralogical analyses of the fossil substrate were undertaken to determine how the footprinted surface was preserved. Comparison with modern lake-marginal processes suggests that the prints were initially stabilized by desiccation, soil-crusting, and organic films, followed by cementation of the surface sediments by calcite and analcime, with minor authigenic clay minerals and Fe-Mn-oxihydroxides. The zeolites formed by reaction of detrital silicates with saline, alkaline groundwater; calcite was precipitated from dilute runoff and fresher groundwaters. Cementation likely occurred during a prolonged period of relatively low, stable lake level. Following cementation, the surface was buried by Holocene lake sediments, then recently exhumed.  相似文献   

8.
Soil crust lichens can be the dominant vegetation in desert regions that are unsuitable for higher plants, and are vital to soil stabilization and primary production. Biological soil crusts are vulnerable to disturbance and there is little evidence of the lichen components achieving full recovery following human disturbances in semi-arid to arid environments, and no records of recovery in hyper-arid deserts. Eight sites with varying anthropogenic, mechanical disturbance regimes were assessed in the hyper-arid Namib Desert for levels of recovery and successional convergence, based on a comparative analysis of overall lichen cover and community composition in disturbed and control locations. Recovery time estimations ranged from 5 to 530 years, with no detected linear relationship to impact gradient (low to high impact). Variables that were found to most strongly influence recovery rates were the overall cover of lichen growth and total number of lichen species in the bordering undisturbed areas, followed by the extent of soil compaction in the disturbed area, altered soil surface microrelief and vitality of subsurface soil crust components. An assessment of pioneering species demonstrated a link between increased soil depressions, i.e. track ruts, and the occurrence of fragmenting, wind-dispersing species. Track ruts in hype-arid deserts are not as vulnerable to the water erosion found in less arid deserts, and may be advancing recovery by trapping fragments. However, the lichen community structure was significantly different between all of the disturbed and control areas, regardless of the recovery phase, suggesting that while the lichen community composition may not. The ecological consequences of such disturbances may be far reaching in hyper-arid deserts where lichens are primary heterotrophs soil stabilizers. Given the economic development occurring within coastal hyper-acid deserts of the world, these impacts undoubtedly call for conservation attention.  相似文献   

9.
Only two vertebrate trackways are known from the Paleocene of western Canada and are among the few Paleocene vertebrate trackways known worldwide.

A natural cast trackway consisting of five prints (three pes, two manus) on a fallen block was found along the Red Deer River, near the town of Red Deer, Alberta, in 1927. The discoverers, Ralph Rutherford and Loris Russell, identified the strata the track block had fallen from as belonging to the Paskapoo Formation (upper Paleocene: middle Tiffanian). The trackway was attributed to a mammalian track-maker in two subsequent publications. However, the prints are more characteristic of a reptilian (crocodylian) track-maker.

A natural cast track-bearing block was discovered on Signal Hill in the city of Calgary during the preparation of a new residential subdivision in 1990. The large track-bearing block was found in a rock pile but is suspected to have originated from strata belonging to the Porcupine Hills Formation (Upper Paleocene: late Torrejonian), which was being excavated at the time. This large slab contains twelve prints (six pes, six manus) and is associated with extensive mud cracks. The mammalian affinity of the trackmaker was recognized by researchers from the Royal Tyrrell Museum of Palaeontology.  相似文献   

10.
On the upper surface of some specimens of the lichen Lobaria cf. crosa (Eschw.) Nyl. there are shrub-like growths which have a morphology similar to that of a free-living fruticose lichen, Polychidium umhausense (Auersw.) Henss., and contain a cyanophyte phycobiont, Nostoc. A few growths also contain scattered colonies of a chlorophyte phycobiont, in which case the lichen tissue locally assumes the foliose form characteristic of the parent Lobaria thallus. The differentiation of dorsiventral lichen cortices and the formation of a lax medulla and distinct algal layer are correlated with the presence of the green phycobiont. The lichen substances atranorin, gyrophoric acid, and 4-0-methylgyrophoric acid occur in both, the foliose L. erosa thallus and the fruticose tissue. It is suggested that the fruticose structures are erumpent cephalodia which are derived from the outgrowth of internal, cephalodia and should not be considered, to be epiphytic colonies of the lichen Polychidium.  相似文献   

11.
中国云南西部地衣区系(英文)   总被引:2,自引:0,他引:2  
对中国云南西部高山地区的大型地衣进行了调查。采集地衣标本400余份,鉴定为46属86种,其中40种在朝鲜半岛有报道。所有采集的标本现保藏于顺天大学韩国地衣研究所和中国科学院昆明植物研究所隐花植物标本馆。  相似文献   

12.
Fluvial palaeochannels of coastal plain sediments of the Lower Jurassic Sose Bugt Member of the Rønne Formation exposed in the coastal cliffs at Sose Bugt, Bornholm, contain abundant dinosaur or other large vertebrate tracks in the form of deformation structures exposed in vertical section. The tracks are represented by steep‐walled, flat‐to‐concave‐bottomed depressions, with a raised ridge at each side. The tracks are filled with laminated sediments, draping the contours of the bottom of the depression. Underprints, stacked concave deformations beneath the prints, are present beneath each track. Contemporary Upper Triassic – Lower Jurassic strata from southern Sweden and Poland contain a diverse track fauna, supporting our interpretation. This is the earliest evidence of dinosaur activity in Denmark.  相似文献   

13.
HPLC-analysis was used to determine the concentrations of the lichen compounds alectoronic acid (depsidon), -collatolic acid (depsidon) and atranorin (depsid) in the lichenized ascomycete Tephromela atra (syn. Lecanon atra) (Hudson) Hafeliner from limestone walls on the Baltic island of Öland, Sweden. In 24 individuals of T. atra sampled on a stone wall, the pre-reproductive and reproductive tissue did not differ in the concentrations of alectoronic acid, collatolic acid and atranorin. The concentrations of the three lichen compounds were inter-correlated in the reproductive tissue, but not in the pre-reproductive tissue. Single individuals of T. atra ranged in area covered from 10.1 to 147.4 cm2 (mean: 38.5 cm2; N=24); 38.6% of this area was pre-reproductive tissue. However, the concentrations of the three lichen compounds were correlated neither with the total area covered by the lichen nor with the percentage of pre-reproductive tissue. This suggests that the concentrations of the lichen compounds do not change with increasing size (age) of the lichen. Analysis of specimens of T. atra from eight localities revealed a significant variation in lichen compounds (range between localities: alectoronic acid 0.60–3.26 μg/mg lichen dry weight (DW); collatolic acid 2.14–11.59 μg/mg lichen DW; atranorin 0.58–4.16 μg/mg lichen DW). The level of grazing observed in the lichens differed significantly among localities. However, no correlations between the concentrations of the three lichen compounds and the grazing damage to the lichens were found.  相似文献   

14.
Lichens are considered bioindicators and, as such, are widely used for air quality monitoring, especially in urban-industrial areas. The present paper proposes an evaluation of lichen communities in urban areas. The corticolous lichen community was assessed at 29 sampling stations in the city of Porto Alegre, in addition to a reference area located in the State Park in the city of Viamão, southern Brazil. The rubber band method was used for lichen mapping; three hundred host-trees were analyzed, at 11 different height levels. Lichens were evaluated in terms of composition, richness, cover and diversity, and sampling stations were classified based on the Index of Atmospheric Purity (IAP) complemented by the Environmental Classification Factor (ECF). The inclusion of ECF as a complement to the original IAP formula is proposed in the present study and not only richness and cover components are considered, but also data on the lichenized mycota composition (considering its different morphological forms). One hundred and thirty-one (131) taxa have been identified, out of which 13 specimens may be considered as indicators of urban areas, and the predominance of taxa belonging to the crustose and foliose morphological group was verified. The sampling stations were classified into five zones, ranging from lichen-free zones to optimal zones for lichen development. The use of lichen proved to be efficient to both evaluate air quality and identify alterations of urban microclimates. The application of an ECF-based correction factor is expected to complement the use of IAP, making it a more sensitive index, since an analysis of a multivaried information profile was deemed necessary, especially in regions where specimen diversity is higher.  相似文献   

15.
以采自新疆地区的地衣标本为试验材料,通过观察和研究该地衣形态解剖特征、次生代谢产物以及构建核糖体DNA内转录间隔区(internal transcribed spacer,ITS)系统发育树,研究鉴定该地衣标本为蜈蚣衣科(Physciaceae)1个中国新记录属:金奥克衣属[Oxnerella(S.Y.Kondr.,Lo″k?s&Hur)]及中国新记录种双裂金奥克衣[O.safavidiorum(S.Y.Kondr.,Zarei-Darki,Lo″k?s&Hur)],该种含有柔扁枝衣酸,文中提供了该种形态解剖图,并讨论了其与相似物种的关系。  相似文献   

16.
A high-performance liquid chromatographic method originally devised to provide a reproducible measure of retention is used to determine chemical structures of new compounds in lichens. The method relates retention to a standard homologous series so that retention indices of members of other homologous series are linear with carbon number. When two or more homologs are known, retention of new members of the same series can be accurately predicted. Combining this method with other microchemical techniques allows the determination of structures of lichen depsides in small samples of crustose species for which the total material is meager and known only from the herbarium. The conditions are sufficiently mild that chemical decompositions of labile depsides are avoided. Eight new orcinol-type p-depsides with seven- or nine-carbon oxidized sidechains on one or both rings are reported from an endemic Japanese species, Haematomma pachycarpum. The nine-carbon sidechain is the longest ever found in lichen depsides. These new compounds are higher homologs of the known lichen products confluentic, 2‘-O-methylperlatolic, 4-O-methylolivetoric, and 2‘-C-methylmicrophyllinic acids. In addition, an isocoumarin with a nine-carbon sidechain occurs in some specimens. Haematomma pachycarpum has the most complex secondary-product chemistry thus far reported for any lichen species. The significance of the technique used here lies in providing a way to characterize new compounds in rare or endangered species, thereby completing data sets for phylogenetic reconstructions.  相似文献   

17.
中国树花对乌鲁木齐南郊空气污染生物指示的研究   总被引:4,自引:1,他引:3  
目的:中国树花对乌鲁木齐南郊空气污染生物指示作用的探讨。方法:采用电感耦合等离子光谱直读法测定移植地衣内重金属含量的变化。结果:地衣体内被测定出的重金属元素种类和含量与移植时间的长短之间存在显著性差异。对照组中,中国树花体内仅测出2种元素,其中Fe和Mn的含量分别为1.2915±0.054μg.g-1和0.0261±0.001μg.g-1。移植1个月后测出Al、Fe、Mn、Zn等4种元素,其含量分别为0.68±0.036、0.706±0.086、0.021±0.016和0.061±0.005μg.g-1;移植3个月后测出Al、Cr、Cu、Fe、Mn、Ni、Zn等7种重金属,其含量分别为0.285±0.039、0.0032±0.001、0.004±0.002、0.499±0.133、0.106±0.015、0.011±0.01、0.011±0.01、0.038±0.002μg.g-1。结论:中国树花在生物评价乌鲁木齐南郊空气污染方面具有一定的研究价值。  相似文献   

18.
Abstract. Two neighbouring even-aged 130-yr old Picea abies trees in a homogeneous stand can differ substantially with respect to their epiphytic vegetation. Sampled branches from the canopy of one tree harboured 781 specimens of the old forest lichen Usnea longissima of which only 50 could be seen from the ground, whereas no U. longissima were found on its nearest neighbour. Usnea longissima was most abundant on branch tips in lower parts of the canopy on branch segments having the highest biomass of other alectorioid species. Trees with and without U. longissima showed a different pattern in their mineral composition, suggesting that a tree-specific difference in nutritional status might contribute to explain the patchy distribution of this lichen within seemingly homogeneous stands.  相似文献   

19.
As part of the long-term monitoring projects on Antarctic terrestrial vegetation in relation to global climate change, a lichen floristical survey was conducted around the Korean Antarctic Station (King Sejong Station), which is located on Barton Peninsula, King George Island, in January and February of 2006. Two hundred and twenty-five lichen specimens were collected and sixty-two lichen species in 38 genera were identified by morphological characteristics, chemical constituents, TLC analysis and ITS nucleotide sequence analysis.  相似文献   

20.
Prevalence of yeasts in 35 leukoplakia and 34 oral lichen planus patients was compared with that observed in persons without oral diseases. Serotype and morphotype were determined on Candida albicans isolates. Yeasts were isolated from the oral cavity specimens of 43.7% of the patients. C. albicans (serotype A) was the predominant species (76% in leukoplakia, 88.2% in lichen planus and 60.8% in healthy persons). Sixteen morphotypes were encountered on malt extract agar, being 732, 733, 734, 753 and 754 the most frequently found. Morphotypes SP1N and SP1Y were the most common on Sabouraud-trypheniltetrazolium agar (68.4% of the isolates from leukoplakia and 73.3% from lichen planus, but only 46.6% of the isolates from healthy oral mucosa showed SP1N morphotype). Presence of oral lesions was associated with a marked reduction in the yeast species and C. albicans biotypes, suggesting that C. albicans and particularly some of its biotypes, show a high potential of adaptation to the changes associated with the development of oral leukoplakia and lichen planus.  相似文献   

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