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31.
A new high-elevation scorpion species of the genus Scorpiops is described from the Indian state of Himachal Pradesh. Scorpiops spitiensis sp. nov. is the second highest-elevation scorpion species in Asia and the first one from India occurring at elevations above 4200 m. The new species closely resembles Scorpiops petersii, but it can be distinguished from it based on a suit of characters, one of which is the presence of 16 trichobothria on the external aspect of the patella, which is unique to the new species. 相似文献
32.
A ten-year multidisciplinary, multi-national and multi-institutional biodiversity inventory project in the Gaoligong Shan region of western Yunnan Province, China generated more than 35,000 specimens of the beetle (Coleoptera) family Carabidae. In this report, first of a planned series, we focus on diversity in tribe Zabrini. Our study of just over 1300 specimens of zabrine carabids from the project, all in genus Amara Bonelli, found a total of 13 species, all previously described, to occur in the study area, with none of them strictly endemic. We present a key for identification of adults of these species, as well as nomenclatural data, diagnoses, illustrations of dorsal habitus and male genitalia, and information about geographical, altitudinal and habitat distributions within the study area and overall geographical distribution for each species. Distributions of the species within the study area are compared, and broader geographical range patterns are characterized. We also discuss a possible role of the Gaoligong Shan region as one source area for the present-day fauna of the Himalaya and southern edge of the Qinghai-Xizang (Tibetan) Plateau. 相似文献
33.
《Palaeoworld》2021,30(4):610-626
An assemblage of microfossils of moderate diversity, with the remarkable occurrence of ECAP acritarchs, is reported from the Ediacaran Krol ‘A’ (= the Mahi Formation) succession of Lesser Himalaya, India. Microfossils occur in the chert nodules exposed in Solan district, Himachal Pradesh. Two microfossils, Barogophycus symmetricus n. gen. n. sp. and Botominella lineata are new to the well-established Krol assemblage. The paper concentrates predominantly on fossil eukaryotic filamentous and coccoidal micro-organism of simple morphology. The assemblage is dominated by remains of prokaryotic cyanobacteria and demonstrates the diversity achieved by microorganisms at the beginning of the Ediacaran Period in the aftermath of the Marinoan glaciation. Filamentous and coccoidal microorganisms differ in taxonomic composition from the Mesoproterozoic microbiotas. The Krol microfossils assemblage has biostratigraphic potential and usefulness in broadly demarcating the different levels of the Ediacaran strata. Because of the presence of ECAP acritarchs, along with the appearance of other eukaryotic microorganisms of filamentous and coccoidal morphology, the general level of the Krol ‘A’ assemblage is considered as Ediacaran. 相似文献
34.
Abstract. Nutrient utilization and growth performance of Pinus roxburghii Sarg. and Quercus leucotrichophora A. Camus, the two major forest trees of the Central Himalaya Mountains between 1000 and 2000 m elevation, were analysed at different nutrient levels. The early successional P. roxburghii occurs naturally on nutrient-poor sites and the late successional Q. leucotrichophora on nutrient-rich sites. Seedlings of these two species were grown both in monoculture and mixed, in plastic bags containing 1 kg soil and representing five levels of nutrients (NPK) in a 12 : 32 : 16 ratio. The P. roxburghii seedlings showed significantly greater nutrient extraction efficiency (nutrient unit extracted by seedlings per nutrient unit in the soil) than the Q. leucotrichophora seedlings, and this difference was increased in interspecific competition, particularly at the higher nutrient levels. In interspecific competition the extraction efficiencies of P. roxburghii for N, P and K were distinctly higher than those of Q. leucotrichophora. This we consider to be the main reason for the replacement of Q. leucotrichophora by P. roxburghii, even on nutrient-rich soils, after disturbance and subsequent increase in light availability. In both the species, re-translocation of nutrients from senescing leaves declined with increasing soil fertility. For example, re-translocation for P. roxburghii was 49% N, 30% P and 32% K at the lowest soil fertility, and 20% N, 8% P and 13% K at the highest soil fertility. 相似文献
35.
The epiphytes present at about breast height on trunks of different size were studied for three major tree species in a seasonally wet forest at 2050 m altitude in the Kumaun Himalaya: Cedrus deodora, Quercus floribunda and Q. leucotrichophora. The total biomass and species number per unit trunk area, were found to increase with trunk size. It was supposed that the results indicated a succession in the type of epiphytic cover from young trunks to older trunks.The amount of loose material (plant remains and soil) per unit area of trunk increased with increasing girth. The C:N ratio in this material was initially very high on the oaks (129–197) and declined with increasing trunk size (to 73–78); the ratio was constant across girth classes in the cedar (86–87).Bryophytes produced most biomass on most trunks; next to them were lichens on the smallest trunks, and flowering plants on the largest. The number of species of epiphytes was similar on all three host species. The results are discussed in relation to contemporary ideas on diversity and strategies.Nomenclature follows: Ganguli (1972, 1977 & 1980); Kashyap (1929); Nayar (1970); Osmaston (1927).Financial support from the Council of Scientific and Industrial Research, Delhi and University Grants Commission, New Delhi is gratefully acknowledged. 相似文献
36.
YUJI OMORI HIDEAKI OHBA F.L.S. 《Botanical journal of the Linnean Society. Linnean Society of London》1996,122(3):269-278
The Himalayan alpine herb, Rheum nobile , terminates in a stout conical compound raceme concealed by large translucent bracts. It bears many fruits even under hostile conditions such as low temperature or persistent cloudy weather. To clarify the role of the bracts, the structure and the development of the pollen grains were examined after removing the bracts to expose the flowers to the open air for 9 days. Half of the individuals with bracts removed showed 0 to 1 % of pollen stainability and the pollen grains were variable in shape and size. It was also observed that the bracts of Rheum nobile increased the temperature of inflorescence by about 10deg;C above ambient daytime temperatures. These results suggest that one of the causes for the inhibition of pollen development was low temperature. The remainder, however, indicated high stainability of 70–100%. It is suggested that the extreme difference of pollen stainability between two groups of Rheum nobile exposed to the surroundings may be related to the stage of microsporogenesis. Bracts of Rheum nobile might play an important role in normal reproduction under low temperature at high altitudes. 相似文献
37.
Forests of an elevational transect in the central Himalayan region were studied regarding their tree species composition and structural features. In spite of many differences in compositional and structural features in different forest stands, the arrangement of stands in the ordinations based separately on species composition and structural features exhibit many similarities. Disturbances such as landslides and forest fires play the most important role in the distributor of particular species. 相似文献
38.
Govindan Selvakumar Piyush Joshi Sehar Nazim Pankaj K. Mishra Samaresh Kundu Hari S. Gupta 《World journal of microbiology & biotechnology》2009,25(1):131-137
Exiguobacterium acetylicum strain 1P (MTCC 8707) is a rhizospheric, Gram positive, rod shaped, yellow pigmented bacterium isolated from an apple orchard
rhizospheric soil, on nutrient agar plates incubated at 4°C. The species level identification was arrived on the basis of
16S rRNA gene sequencing. The sequence showed 98% similarity with sequences of E. acetylicum available in the public domain. The strain was positive for siderophore and HCN production. In separate invitro assays it
was found to inhibit the growth and development of Rhizoctonia
solani, Sclerotium rolfsii, Pythium and Fusarium oxysporum. The volatile compound produced by the bacterium was found to be the most potent in inhibiting the hyphal development of
R. solani, S. rolfsii, Pythium and F. oxysporum by 45.55, 41.38, 28.92 and 39.74% respectively. Commonly observed deformities caused by the diffusible and volatile compounds
produced by the bacterium included hyphal inhibition, constriction and deformation. Under pot culture conditions the bacterium
improved the germination and early growth parameters of pea (Pisum sativum) in the presence of R. solani and S. rolfsii. 相似文献
39.
Cold desert regions harbor a unique habitat for a number of high-value medicinal plants (HMPs) and due to inaccessibility of medical facility, inhabitants of this region are highly dependent on medicinal plants. Over the years, with increasing demand for trade, extraction pressure on natural populations of these HMPs has grown substantially. This consequently has made such plants threatened in their natural habitats. However, quantification of threat intensity is lacking. For the first time, this study has attempted to identify and assess the ecological and threat status of HMPs from the cold desert area of Johar valley, West Himalaya, India. For ecological assessment, rigorous field surveys were conducted along the elevation gradient. The intensity of threat was evaluated by using rapid threat assessment (RTA) approach. A total of 22 threatened and high-value medicinal plants (THMPs) were identified from the region. Results of RTA placed Betula utilis and Nardostachys jatamanasi in the highest threat category. Roots/rhizomes were the frequently (55%) used plant parts, followed by inflorescence/fruit and stem/bark (18%) each. Overall, this study provides a clear picture of ecological and threat status of THMPs of the study area, which can effectively be utilized to develop a suitable conservation model for the region. 相似文献
40.
Isolation and characterization of actinomycetes from soil samples from altitudinal gradient of North-East India were investigated for computational RNomics based phylogeny. A total of 52 diverse isolates of Streptomyces from the soil samples were isolated on four different media and from these 6 isolates were selected on the basis of cultural characteristics, microscopic and biochemical studies. Sequencing of 16S rDNA of the selected isolates identified them to belong to six different species of Streptomyces. The molecular morphometric and physico-kinetic analysis of 16S rRNA sequences were performed to predict the diversity of the genus. The computational RNomics study revealed the significance of the structural RNA based phylogenetic analysis in a relatively diverse group of Streptomyces. 相似文献