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D.X.HU 《中国海洋湖沼学报》2004,22(3):J001-J002
Ocean circulation in the Yellow and East China Seas is very rich in mesoscale phenomena, such as eddies, fronts, upwellings, river plumes, etc. Among others, having drawn tremendous attention from oceanographic community in the past for nearly 50 years are mainly the Yellow Sea Cold Water Mass (YSCWM) and its related circulation, the Yellow Sea Warm Current (YSWC), the East China Sea 相似文献
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Hemant K. Badola Jitendra S. Butola 《山地科学学报》2005,2(2):173-180
This paper examines the effect of ploughing depths (A -- 60 cm, B -- 45 cm and C -- 30 cm) on the growth and yield of Heracleum candicans Wall (Apiaceae), a threatened medicinal herb of the Himalayan region. This less-explored plant is being suggested as a potential crop for the mountain agriculture. The study was carried out in an orchard in Himachal Pradesh, India at 2500 m altitude, for two successive growth years. During the first year, all plants remained in juvenile state; in the second year, nearly 65 % plants produced flowers only under 60cm ploughing depth. Among its morphological traits, plant height, collar diameter and aboveground flesh weight were found to be strongly correlated (P 〈 0.01) with the belowground biomass during the first year (r =0.968, 0.925 and 0.973, respectively) and during the second year (r=0.945, 0.928 and 0.775, respectively). Increase in the ploughing depth was significantly correlated (P〈0.01) with all growth parameters, including the belowground dry weight, marketable portion of the produce. The belowground biomass (commercial yield; 16.28 Qt/hec) at depth A was about 2.6 and 4.7 times higher than those recorded at depths B and C, respectively. The results clearly justify the importance of deep ploughing and this paper strongly recommends it for economically sustainable cropping. 相似文献
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驻马店市土地、矿产管理机构组建于1986年11月。20年来,驻马店市国土资源局以科学发展观统领全局,正确处理经济社会发展与资源保护的关系,有力地促进了全市经济社会协调、快速发展。耕地保护得到加强,建设用地得到保障。20年来,该局严把征地和土地转用审批关,严格控制非农业建设占用耕地,确保基本农田稳定;把确保重点项目建设用地作为中心工作来抓,大力开展“三项整治”,充分利用闲置土地和存量土地,优化国有资产配置,保障项目建设用地需求。20年来,该市土地市场逐步规范,土地有偿使用制度改革进一步深化。大力推进土地有偿使… 相似文献
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Irvine WM Friberg P Hjalmarson A Ishikawa S Kaifu N Kawaguchi K Madden SC Matthews HE Ohishi M Saito S Suzuki H Thaddeus P Turner BE Yamamoto S Ziurys LM 《The Astrophysical journal》1988,334(2):L107-L111
We report the astronomical identification of the cyanomethyl radical, CH2CN, the heaviest nonlinear molecular radical to be identified in interstellar clouds. The complex fine and hyperfine structures of the lowest rotational transitions at about 20.12 and 40.24 GHz are resolved in TMC-1, where the abundance appears to be about 5 x 10(-9) relative to that of H2. This is significantly greater than the observed abundance of CH3CN (methyl cyanide) in TMC-1. In Sgr B2 the hyperfine structure is blended in the higher frequency transitions at 40, 80, and 100 GHz, although the spin-rotation doubling is clearly evident. Preliminary searches in other sources indicate that the distribution of CH2CN is similar to that for such carbon chain species as HC3N or C4H. 相似文献
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Kumar K Taragi RC 《Population geography : a journal of the Association of Population Geographers of India》1986,8(1-2):58-63
There are great spatial variations in the distribution of the fast growing populations of India. About 70% of the 1981 population is concentrated in only 40% of the geographical area. Such a pattern of population concentration, with its spatio-temporal dimension, can be understood better if examined at the macro-regional level considering the physico-climatic and socio-economic diversity of the country. This is done by way of analyzing district level data for India as a whole and also for its various macro-regions. The study reveals that the Great Plains and Coastal Plains and Islands have a homogenous distribution and a higher population increase. The Deccan Plateau shows the most homogenous dispersion of population. The population is declining in the Northern Mountains and the Great Plains but accentuating in the Coastal Plains and Islands and the Deccan Plateau. The north and south of India are showing opposite trends in population concentration. 相似文献
8.
The Nordic geological surveys: Geology for society in practice 总被引:1,自引:0,他引:1
Morten Smelror Andreas AhlstrФm Lena Ekelund Jens Morten Hansen Keijo Nenonen Anette K. Mortensen 《《幕》》2008,31(1):193-200
Since the mid-nineteenth century., when the first of the Nordic Geological Surveys were established, they have generated a substantial amount of information on the Earth's crust, its natural resources, its processes, and on the geological history of Nordic areas. The collective mission of the geological surveys is to carry out "Geology for Society", by doing research and providing services, and by making geological information and data easily accessible to all the varied end users in industry, government agencies, government institutes, public administrations, technical offices, academia and research institutes, as well as for private individuals. The present paper gives a brief overview of a few, selected, research areas and projects currently undertaken by the Nordic geological surveys. These serve as practical examples of how the Nordic geological surveys address important societal problems and challenges that require geological input for their solution. 相似文献
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