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1.
Field investigations of the Palaeogene sections exposed in Barmer district, Rajasthan (India) led to the discovery of a new fossiliferous horizon in the Padma Rao Open Cast Bentonitic Clay Quarry. The bentonitic clay sequence of this quarry is considered as representing the upper part of the shale, carbonaceous shale, lignite and bentonitic clay succession of the Akli Formation exposed in the Giral Lignite Mine, 2.5 km to its north. Screen-washing of the sediments from a fossiliferous level within the bentonitic clay of the new site has yielded nine taxa of sharks and batoids: Squatiscyllium nigeriensis White, 1934, Ginglymostoma sokotoense White, 1934, Ginglymostomatidae gen. et sp. indet., Brachycarcharias sp., Abdounia recticona Winkler, 1873, Premontreia (Oxyscyllium) peypouqueti Noubhani et Cappetta, 1997, Eotorpedo hilgendorfi Jaekel, 1904, Coupatezia sp. cf. C. danica, and Myliobatidae gen. et sp. indet. The fauna recovered is mainly represented by nearshore shallow marine forms. This fauna is quite different from that of Palaeocene Fatehgarh Formation, the Lower Eocene Kapurdi Formation (Barmer Basin), the Khuiala Formation (Jaisalmer Basin) and the Cambay Shale (Cambay Basin), and favours a late Palaeocene (Thanetian) age for the upper part of the Akli Formation. A nearshore shallow marine palaeoenvironment is favored for the investigated stratigraphic horizon on the basis of the selachian fauna. Majority of the fossil shark species described from the Padma Rao quarry section are known from a number of sites in Africa, western Europe, Asia and southeastern USA, suggesting that free faunal interchanges were possible between the western Tethys and Indo-Madagascan faunal provinces during the late Palaeocene.  相似文献   

2.
Rotifer fauna of Rajasthan,India   总被引:4,自引:4,他引:0  
Summary Thirty six species of rotifers have been reported from Rajasthan including a new species of Monostyla. Lecane dorsicalis ARORA (1965) is regarded as a synonym of L. luna (Muller) 1776.  相似文献   

3.
The present paper deals with investigations of less known medicinal plant lore among the aboriginal Nicobarese tribe of Car Nicobar island, India. Information on 73 species and their therapeutic applications and manner of use are initially documented and described as remedies in folkloric tradition and popular domestic medicine. No chemical principles are identified; no putative herbal remedies are pharmaceutically and medically evaluated. The aim of this paper is to gather information concerning medicinal plants and to provide access to specialists in search of their applications in modern medicine. A brief account of geography, climate, ethnology, and methodology adopted is given. Vernacular name(s) of the plants in the Nicobarese language are incorporated for the first time in the literature.  相似文献   

4.
L. N. Vyas  H. D. Kumar 《Hydrobiologia》1968,31(3-4):421-434
Summary A study has been made of the productivity and periodicity of phytoplankton of the Indrasagar tank, Udaipur, in relation to physicochemical characteristics. Variations in the physical and chemical characteristics of water over a period of one year are described.The Tank is of eutrophic type. Green algae dominated the phytoplankton both as regards number of species and number of individuals.A definite phytoplankton periodicity has been observed, the green algae dominating in the rainy and winter seasons and the blue-greens during summer.A correlation of the phytoplankton productivity and physicochemical characteristics of Indrasagar tank indicates that the Chlorophyceae have a wide range of adaptability; the growth of diatoms is promoted by silica, nitrates and phosphates; and the growth of blue-green algae is controlled by pH and temperature.  相似文献   

5.
Summary The literature on the demarcation line between the Indo-Malayan and the Perso-Arabian floras is reviewed and it is proposed to base the delimitation on the vegetation types. In the forests of teak or miscellaneous species generally located on the hills, the Indo-Malayan and the Indian elements predominate but in the thicket or scattered shrubby vegetation ofProsopis, Salvadora, Acacia, Capparis, Euphorbia of the sandy alluvial plains of North Gujarat and Rajasthan the western element is conspicuous.Geologically, Rajasthan west of the Aravallis possesses a mingling of the distinctive characters of the Peninsula and the extra-Peninsula and cannot be referred to as either. It is shown that plantgeography does not provide any evidence to consider the area as probably peninsular as suggested previously.  相似文献   

6.
This study reveals disjunct distribution patterns of certain plant species on zinc-rich soils in the Zawar mines region near Udaipur. Ten plant species have high constancy and fidelity values on zinc-rich soils in comparison to normal soil. The plant community composed of these species has been named Impatiens balsamina-Triumfetta pentandra association. As Impatients balsamina is the most characteristic species on metal dumps, it can be considered as a local indicator for the metal zinc.Acknowledgements: The authors are grateful to the University Grants Commission of India, New Delhi for substantial financial assistance.  相似文献   

7.
Cladocera of Rajasthan   总被引:4,自引:4,他引:0  
C. K. G. Nayar 《Hydrobiologia》1971,37(3-4):509-519
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8.
Nomadization in Rajasthan, India: Migration, Institutions, and Economy   总被引:1,自引:0,他引:1  
Despite a global trend toward settlement, the incidence of pastoral nomadism is on the rise in the Marwar region of Rajasthan, India. Typical explanations for this change use models of population pressure; increasing herds and decreasing pasture are held to blame. This explanation, however intuitive, is unsatisfactory. Instead, changing institutional and economic patterns are creating new contexts for strategic movement. Bottlenecks in the yearly resource calendar, caused by the disintegration of obligatory social relationships, force migrations during periods of scarcity. Changes in the volume and pattern of the meat and wool markets have also created opportunities for migrating pastoralists. Producers increase their access to markets and the reproductive rate of their herd through long, annual, migration. While nomadism is a general adaptation to changes in the socioeconomic conditions of the region, differential resource endowments account for the range of strategies; wealthy herders have opportunities not enjoyed by more marginal producers.  相似文献   

9.
10.
Several plants of the Zawar Zinc Deposits of Rajasthan (India) accumulate very high levels of cadmium. The maximum concentration namely 420 micrograms g-1 was found in the stems of Crotalaria linifolia. Some other cadmium accumulators with the concentration of the metal in microgram g-1 are Impatients balsamina (380), Dyerophytum indicum (282) and Melhania futteyporensis (245). The sequence of cadmium accumulation in different organs of the same plant species was roots greater than stems greater than leaves. Cadmium levels in the leaves of Celosia argentea, Crotalaria linifolia, Impatiens balsamina and Triumfetta pentandra showed a significant (linear) plant-soil relationship. The respective biological absorption coefficients (BAC - concentration of the element in the plant divided by concentration of the same element in the substrate) for these plants were 2.74, 4.13, 5.49 and 4.65.  相似文献   

11.
Investigations on 105 individuals from the Kannikar tribals of Nedumangard Taluk of Kerala (India) showed a fast moving albumin variant (9.5%) in pH 8.6. Both monomeric and dimeric variants were detected. 8.5% of the variants were found in the most interior group of these tribals.  相似文献   

12.
The World Health Organization(WHO)estimatesthat as manyas80%of the world′s populationrely pri-marily on plant and animal-based medicines.Amongthe252essential chemicals that have been selected bythe World Health Organization,11.1%comefrompla-nts,and8.7%fr…  相似文献   

13.
Two alkaline saline inland lakes of Indian arid region were studied during 1984 and 1985, to assess functioning and interaction of various environmental and biological factors. Changes in physical and chemical variables, planktonic composition, chlorophyll content and phytoplankton primary productivity were examined.Salinity in both lakes fluctuated from almost fresh water (1.80), to hypersaline (300) and acted as the main controlling factor for almost all the biotic parameters. Maximum total alkalinities were 2162 mg l–1 and 2090 mg l–1, respectively in Sambhar and Didwana lakes. Dissolved oxygen ranged from completely anoxic conditions to maxima of 11.68 and 7.29 mg 1–1, respectively in Sambhar and Didwana lakes. Nutrient enrichment in the lakes was low.The phytoplankton species composition of Sambhar lake was reduced from an earlier reported 20 genera to only 11 (Nostoc, Microcystis, Spirulina, Aphanocapsa, Oscillatoria, Merismopedia, Nitzschia, Navicula, Synedra, Cosmarium and Closterium). Phytoplankton of Didwana was composed of only 9 genera including Anabaena and Nodularia. Sambhar lake, which once contained Artemia, is now totally devoid of them. On the other hand, Artemia was the most dominant zooplankter in Didwana lake at a salinity range of 15–288. Other zooplankters such as Moina, Cyclops and Brachionus flourished at lower salinity levels in Didwana lake. The seasonal quantitative and qualitative phyto- and zooplankton changes in relation to salinity are documented.  相似文献   

14.
吴健生  沈楠 《生态学报》2017,37(22):7483-7492
城市公园绿地是当代城市的重要组成部分,居民能否方便地享用公园绿地所提供的各项服务与功能,是衡量一个城市人地关系和谐状况、现代化发展水平和居民生活质量的重要指标,也是城市公园绿地社会服务功能的体现。选取深圳市福田区为研究对象,计算单点绿地步行指数,衡量均质区域的公园绿地步行可达性;基于土地利用类型法实现人口数据空间化;基于面域绿地步行指数耦合绿地空间分布与人口格局,评估深圳市福田区居民通过步行方式到达城市公园绿地的便利程度,即城市公园绿地的社会服务功能水平。结果表明:深圳市福田区在区域均质假设下,公园绿地步行可达性整体较好,区域差异较大,呈现出东优西劣的趋势,梅林公园周边、莲花山公园南部、荔枝公园周边及皇岗公园周边是四个公园绿地步行可达性最好的区域,福田区西北部和西南部公园绿地步行可达性差;供需平衡视角下,70%街道的居民可以便捷、公平地享用城市公园绿地所提供的服务,华强北街道、莲花街道、园岭街道和华富街道公园绿地设施建设非常完善,且绿地格局与人口格局配置合理,香蜜湖街道与沙头街道开放性公园绿地建设状况有待改进。将步行指数应用于公园绿地建设状况评估,为步行城市建设、公园绿地空间布局优化提供参考依据。  相似文献   

15.
Moths are phytophagous, cosmopolitan, agricultural pests, night pollinators, chiefly nocturnal and potential bio-indicators. The current study will be the first report on species diversity, species composition, abundance, and distributional pattern of moth fauna in Aravalli Hill Range Rajasthan. During the survey period of 2018–2019, 758 specimens of moths were collected pertaining to 34 species, 26 genera belonging to 05 families, and 13 subfamilies from three different sites of Aravalli Hill Range. Based on the number of genera, family Sphingidae was most dominant with 9 genera, and family Crambidae was least dominant with 2 genera. Based on the number of species, the family Sphingidae was the most dominant, representing 13 species, followed by Erebidae representing 11 species, Saturniidae and Noctuidae with 4 species each, the least dominant was Crambidae with 2 species. The diversity indices for moths have been calculated for the first time from the Aravalli Range of Rajasthan. Across the survey, Simpson’s Diversity Index (D′), Shannon Diversity Index (H′), Dominance & Evenness was calculated as 0.95, 3.3, 0.04, and 0.8, respectively, which reflects that moth fauna is diverse in the surveyed areas.  相似文献   

16.
R. C. Bowen 《CMAJ》1978,118(3):236
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17.
The observations on net above-ground biomass and production in a large protected area of monsoonal vegetation at Jodhpur (India) are presented in this paper. With the start of the monsoon (July–August) a distinct increase in biomass was noted and by winter (November–December), the biomass, decreased as there was hardly any moisture in the soil. The ephemerals, especially some of the grasses form the bulk of biomass in the total make-up. The biomass and production appeared to be closely related in the monsoonal vegetation of this area. The maximum biomass value (360.5 g/m2) was observed in the month of September, decreasing thereafter.  相似文献   

18.
A new species of the endogonaceous fungus Gigaspora, isolated from the Indian semi-arid region, is described. The fungus, named G. tuberculata, produces rusty-brown azygospores with septate subtending hypha. The azygospores bear warts all over the outer wall. The shape, size and general appearance of these spores resemble those of Scutellospora persica.Neeraj and A.K. Varma are with the Microbiology Unit, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110 067, India; K.G. Mukerji is with the Applied Mycology Laboratory, Botany Department, University of Delhi, Delhi 110 006, India. B.C. Sharma is with the Department of Textile Engineering, Indian Institute of Technology, New Delhi 110 016, India.  相似文献   

19.
The effects of residential density were examined in the following study through a comparison of experiences of tenants living in 14-story apartment buildings and those in three-story walkups within the same low-income housing project. It was hypothesized that tenants in the high-rise buildings would come into contact with large numbers of others in the public spaces of their buildings. As these contacts exceeded residents' interaction capacity or ability to process relevant incoming social stimuli tenants would experience social overload. This experience would be manifested by tenants' perceptions of crowding in the building, feelings of less control, safety, and privacy in the immediate residential environment, problematic social relationships among tenants and alienation and dissatisfaction with the residential environment generally. These experiences were not expected to occur for tenants in the low-rise walkups. Interview data supported these hypotheses and revealed, in addition, that high-rise apartment residents were less socially active beyond their building and felt a greater sense of powerlessness in effecting management decisions. Correlational analyses provided further evidence of the vast differences between residents' experiences of the two building types.  相似文献   

20.
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