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Characteristics of Garden Culture in Southern Region of the Five Ridges
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作者 王兆东 《Journal of Landscape Research》 2010年第8期48-50,55,共4页
Geographical conditions, humanistic environment and garden development history in the southern region of the Five Ridges (or Lingnan, "Ling" means "ridge", "nan" means "south") ... Geographical conditions, humanistic environment and garden development history in the southern region of the Five Ridges (or Lingnan, "Ling" means "ridge", "nan" means "south") were introduced in this study, and characteristics of garden culture in this region were analyzed. 展开更多
关键词 southern region of the five ridges (Lingnan) Garden CHARACTERISTICS
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Cu-Zn isotope compositions of hydrothermal sediments from the southern Mid-Atlantic Ridge:implications to the sediment formation and mineral exploration
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作者 Baoju YANG Lianhua HE +3 位作者 Chuanshun LI Qiannan HU Bingfu JIN Jihua LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第5期1470-1485,共16页
Six hydrothermal sediment samples were collected from the Xunmei and Tongguan hydrothermal fields along the southern Mid-Atlantic Ridge during the China Ocean Cruise DY46 in 2017.Sulfides and oxides in the samples wer... Six hydrothermal sediment samples were collected from the Xunmei and Tongguan hydrothermal fields along the southern Mid-Atlantic Ridge during the China Ocean Cruise DY46 in 2017.Sulfides and oxides in the samples were separated,and Cu and Zn isotope compositions were analyzed.Results show that the ranges ofδ^(65)Cu values of the bulk sediments,sulfides,and oxides were 0.36‰-2.46‰,-0.21‰-1.10‰,and 0.68‰-1.52‰,respectively.Theδ^(65)Cu values of sulfides in four samples(46II-14,46II-30,46III-06,and 46II-09)were relatively low(-0.21‰-0.50‰),corresponding to theδ^(65)Cu values of sulfides from inactive old hydrothermal chimneys in northern Mid-Atlantic Ridge(n MAR),suggesting that the sulfides in the sediments were originated from collapsed dead chimney mainly.While theδ^(65)Cu values of the other two samples(46III-02 and 46III-08)were relatively high(1.10‰-0.96‰),corresponding to theδ^(65)Cu values for active hydrothermal chimneys sulfides in n MAR,which indicated that the sulfides in these two samples might mainly come from sulfide particles settled from active hydrothermal plume.Because of the high density of sulfide particles,they tended to settle near the hydrothermal vents first.Therefore,highδ^(65)Cu values of sulfides in 46III-02 and 46III-08 implied that undiscovered active hydrothermal vents near the sampling positions of 46III-02 in the Xunmei hydrothermal field and 46III-08 in the Tongguan hydrothermal field.Theδ^(66)Zn values of hydrothermal sediments and sulfides ranged 0.11‰-0.43‰and 0.29‰-0.67‰,respectively.In the four samples from the Xunmei hydrothermal field,a positive correlation was found between the distance of the sampling position from sulfide mineralized spot and the Zn isotopic ratio,showing that the greater the distance from the mineralized spot,the heavier the Zn isotope composition as seen in two samples(46II-30 and 46II-14)of the Xunmei-3 spot.This result aligned with the findings of Wilkinson et al.(2005)and Baumgartner et al.(2023),suggesting that the lower the Zn isotope composition,the closer it is to the hydrothermal vent.However,in the Xunmei hydrothermal field,the Zn isotope composition in the other two samples(46III-02and 46III-06)showed the opposite trend.This indicated that there might be an active hydrothermal vent near the sampling location of sample 46III-02.This observation aligned with the Cu isotope analysis results.This study showed that Cu-Zn isotopes are good indicators for understanding the formation mechanisms of hydrothermal sediments and for locating active hydrothermal vents. 展开更多
关键词 Cu-Zn isotope hydrothermal sediments mineral exploration southern Mid-Atlantic Ridge
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Wave Characteristics at the South Part of the Radial Sand Ridges of the Southern Yellow Sea 被引量:6
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作者 杨斌 冯卫兵 张俞 《China Ocean Engineering》 SCIE EI CSCD 2014年第3期317-330,共14页
Based on one-year wave field data measured at the south part of the radial sand ridges of the Southern Yellow Sea, the wave statistical characteristics, wave spectrum and wave group properties are analyzed. The result... Based on one-year wave field data measured at the south part of the radial sand ridges of the Southern Yellow Sea, the wave statistical characteristics, wave spectrum and wave group properties are analyzed. The results show that the significant wave height (H1/3) varies from 0.15 to 2.22 m with the average of 0.59 m and the mean wave period (Tmean) varies from 2.06 to 6.82 s with the average of 3.71 s. The percentage of single peak in the wave spectra is 88.6 during the measurement period, in which 36.3% of the waves are pure wind waves and the rest are young swells. The percentage with the significant wave height larger than 1 m is 12.4. The dominant wave directions in the study area are WNW, W, ESE, E and NW. The relationships among the characteristic wave heights, the characteristic wave periods, and the wave spectral parameters are identified. It is found that the tentative spectral model is suitable for the quantitative description of the wave spectrum in the study area, while the run lengths of the wave group estimated from the measured data are generally larger than those in other sea areas. 展开更多
关键词 wave characteristics wave spectra wave group cold storms radial sand ridges southern Yellow Sea
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Re-Os Isotopic Dating of a W-Be Polymetallic Deposit in the Southern Qinling Region, China 被引量:5
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作者 DAI Hongzhang WANG Denghong +1 位作者 WANG Chenghui HUANG Fan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第1期414-415,共2页
Objective In recent years, a series of tungsten prospecting breakthroughs have been made in the southern Qinling Mountains. Especially, a new deposit type with a scheelite -beryl-molybdenite assemblage in the Zhen'a... Objective In recent years, a series of tungsten prospecting breakthroughs have been made in the southern Qinling Mountains. Especially, a new deposit type with a scheelite -beryl-molybdenite assemblage in the Zhen'an area of Shaanxi Province was firstly discovered. This deposit is currently in a detailed investigation stage, and no detailed study has been yet conducted. This work selected one molybdenite sample from the Be (W) ores in this deposit for Re-Os isotope measurements to define the time limit of tungsten and beryllium mineralization, and to further reveal the ore-forming geological setting of rare metals in the southern Qinling region. 展开更多
关键词 Re-Os Isotopic Dating Re-Os Isotopic Dating of a W-Be Polymetallic Deposit the southern Qinling region
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Response of Artificial Grassland Carbon Stock to Management in Mountain Region of Southern Ningxia, China 被引量:7
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作者 TANG Long DANG Xiaohu +2 位作者 LIU Guobin SHAO Chuanke XUE Sha 《Chinese Geographical Science》 SCIE CSCD 2014年第4期436-443,共8页
Grassland is a major carbon sink in the terrestrial ecosystem. The dynamics of grassland carbon stock profoundly influence the global carbon cycle. In the published literatures so far, however, there are limited studi... Grassland is a major carbon sink in the terrestrial ecosystem. The dynamics of grassland carbon stock profoundly influence the global carbon cycle. In the published literatures so far, however, there are limited studies on the long-term dynamics and influential factors of grassland carbon stock, including soil organic carbon. In this study, spatial-temporal substitution method was applied to explore the characteristics of Medicago sativa L. (alfalfa) grassland biomass carbon and soil organic carbon density (SOCD) in a loess hilly region with different growing years and management patterns. The results demonstrated that alfalfa was the mono-dominant community during the cutting period (viz. 0-10 year). Community succession began after the abandonment of alfalfa grassland and then the important value of alfalfa in the community declined. The artificial alfalfa community abandoned for 30 years was replaced by the S. bungeana community. Accordingly, the biomass carbon density of the clipped alfalfa showed a significant increase over the time during 0-10 year. During 0-30 year, the SOCD from 0-100 cm of the soil layer of all 5 management patterns increased over time with a range between 5.300 ± 0.981 kg/m2 and 12.578 ± 0.863 kg/m2. The sloping croplands had the lowest SOCD at 5.300 ± 0.981 kg/m2 which was quite different from the abandoned grasslands growing for 30 years which exhibited the highest SOCD with 12.578 ± 0.863 kg/m2. The ecosystem carbon density of the grassland clipped for 2 years increased 0.1 kg/m2 compared with the sloping cropland, while that of the grassland clipped for 10 years substantially increased to 10.30 ± 1.26 kg/m2. Moreover, the ecosystem carbon density for abandoned grassland became 12.62± 0.50 kg/m2 at 30 years. The carbon density of the grassland undisturbed for l0 years was similar to that of the sloping cropland and the grassland clipped for 2 years. Different management patterns imposed great different effects on the accumulation of biomass carbon on artificial grasslands, whereas the ecosystem carbon density of the grassland showed a slight increase from the clipping to abandonment of grassland in general. 展开更多
关键词 artificial Medicago sativa L. (alfalfa) grassland clipped grassland abandoned grassland carbon sink carbon density mountain region southern Ningxia
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Climate-Driven Changes in Lake Areas for the Last Half Century in the Valley of Lakes, Govi Region, Southern Mongolia 被引量:1
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作者 Alexander Orkhonselenge Goro Komatsu Munkhjargal Uuganzaya 《Natural Science》 2018年第7期263-277,共15页
This study presents the changes in lake areas in the Valley of Lakes, the Govi region, southern Mongolia. The recent changes in lake areas show decreases depending on vulnerability of lake basins and response of Govi ... This study presents the changes in lake areas in the Valley of Lakes, the Govi region, southern Mongolia. The recent changes in lake areas show decreases depending on vulnerability of lake basins and response of Govi landscape to the present climatic warming. During the recent 44 - 45 years (from 1970 to 2014 or 2015), modern lakes have encountered the present rapid increase in temperature, water evaporation and drying up that induced the reduction in lake areas in the Valley of Lakes. The finding of the reduction in lake areas is consistent with the trends on increasing in temperature since 1995 and fluctuating precipitation since 1975. Investigations with detailed chronology of lake sediment are needed from the lakes to review a more complete evolution of lake basins during the Late Quaternary paleoclimatic history in Mongolia and Central Asia. 展开更多
关键词 LAKES Lake Areas CLIMATE Change Govi region southern Mongolia
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Planting Performance of Pennisetum purpureum Schumab cv.Purple in the Southern Region of China 被引量:1
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作者 易显凤 赖志强 +4 位作者 姚娜 蔡小艳 韦锦益 赖大伟 梁永良 《Agricultural Science & Technology》 CAS 2016年第3期667-671,共5页
[Objective] The present experiment was conducted to investigate the yield,adaptability and quality characteristics of Pennisetum purpureum Schumach cv. Purple to provide reference for the certification and development... [Objective] The present experiment was conducted to investigate the yield,adaptability and quality characteristics of Pennisetum purpureum Schumach cv. Purple to provide reference for the certification and development of new varieties.[Method] With P. purpureum Schumab cv. Purple as experimental material, the variety comparison tests were conducted in Nanning, Lingyun, and Tiandeng in Guangxi from 2007 to 2009, and variety regional trials were conducted in Danzhou of Hainan, Fuzhou of Fujian and Zhanjiang of Guangdong from 2011 to 2013. Its comprehensive characters of plant height, hay yield, stem-leaf ratio and nutritional components were determined, and were compared with those of P. purpureum × P.americanum cv. Reyan No.4 and P. purpureum Schum cv. Guiminyin. [Result] The average height of P. purpureum Schumach cv. Purple was 706.54 cm, which was5.92% and 8.44% lower than that of P. purpureum × P. americanum cv. Reyan No.4 and P. purpureum Schum cv. Guiminyin, respectively. The average hay yield of P. purpureum Schumach cv. Purple was 32.74 t/ha in Nanning, Lingyun, and Tiandeng of Guangxi from 2007 to 2009, and 22.41 t/ha in Danzhou of Hainan, Fuzhou of Fujian and Zhanjiang of Guangdong from 2011 to 2013. Although its hay yield was lower than two control varieties, the difference was not significant(P 0.05).The stem-leaf ratio of P. purpureum Schumach cv. Purple was 0.98:1. Moreover,the analysis on the nutritional components of dry matter showed that compared with P. purpureum × P. americanum cv. Reyan No.4 and P. purpureum Schum cv.Guiminvin, the crude fiber of P. purpureum Schumab cv. Purple was decreased by4.76% and 2.78%, respectively; the neutral detergent fiber decreased by 5.07% and2.22%, respectively; the acid detergent fiber was decreased by 2.54% and 1.99%,respectively; the crude fat was increased by 64.29% and 43.75%, respectively; the calcium content was increased by 28.00% and 33.33%, respectively; the phosphorus content was increased by 9.68% and 22.73%, respectively; the total content of amino acid was increased by 43.23% and 68.41%, respectively; the anthocyanin content of leaf was increased by 400.00% and 216.90%, respectively(P 0.05).[Conclusion] P. purpureum Schumach cv. Purple is a new high-quality forage variety with wide adaptability, high yield, rich nutrient and good palatability, which is appropriate for comprehensive exploitation and application in the southern region of China. 展开更多
关键词 P.purpureum Schumab cv.Purple Plant height Hay yield Stem-leaf ratio Nutritional component southern region of China
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A comparison of the management models of protected areas between China and the southern Africa region
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作者 Claudino DA VEIGA MENDONA 《Forestry Studies in China》 CAS 2010年第3期151-157,共7页
A comparison of the management models of protected areas between China and the African south region allows reading and evaluating the similarities and differences in the use of management model as a management tool fo... A comparison of the management models of protected areas between China and the African south region allows reading and evaluating the similarities and differences in the use of management model as a management tool for protected areas and specifi- cally some positive and negative features of the management approaches in these two regions. Previous to this study it verified the designation of protected areas as increasing at a faster rate than ever before, comparatively much faster now in China than southern Africa regions. With the aim of evaluating similarities and differences in the use of management model as a management tool for pro- tected areas in China and southern Africa Region, both qualitative and quantitative data were collected. Qualitative data were mainly from policy documents, scientific articles and magazine reports, whereas quantitative (secondary data) statistical data from Interna- tional Union for Conservation of Nature Resources (IUCN) and World Database on Protected Areas (WDPA). In view of the data sources above, the study found that in China all the protected areas are state owned whilst in southern Africa regions there are some protected areas that are privately owned; also that the models or typology of governance applied are successful for the fact that they both combine co-management or collaborative management, community-conserved areas and private protected areas that are subject to greater success and can help design planning and management than those who use exclusively government management. To this, the study concluded that the use of management model is influenced by the type of governance a country applies to its reserved areas. 展开更多
关键词 protected areas SUSTAINABILITY China southern Africa region management model
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Distribution characteristics of sea surface temperature along the southern coastal region of Zhejiang Province
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作者 韩小燕 潘晓东 马林芳 《Marine Science Bulletin》 CAS 2013年第1期27-38,共12页
The SST temporal and spatial distribution in the southern coast of Zhejiang is presented as the result of statistical analysis based on the observation data of 51 years from Dachen, kanmen and Nanji gauge stations. It... The SST temporal and spatial distribution in the southern coast of Zhejiang is presented as the result of statistical analysis based on the observation data of 51 years from Dachen, kanmen and Nanji gauge stations. It shows that the overall SST along the coast is higher in the southern part and lower in the northern part, and the discrepancy between south and north parts becomes smallest in winter and largest in summer. Along the southern coast of Zhejiang, SST as a whole generally has a uptrend at rising the rate of 0.017 ℃/ a in last 51 years. In addition, there are oscillation periods of 3.5 a, 5 - 6 a and 11 a stay with SST changes. Mainly, the annual cyclical variation determines SST with a good match of harmonic fitting effect. 展开更多
关键词 the southern coastal region of Zhejiang SST homogeneous power spectrum harmonic
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Palaeomagnetic and Rockmagnetic Behaviour of Dykes from Hyderabad Granitic Region, Part of Eastern Dharwar Craton, Southern India
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作者 B.Madhusudan RAO R.SANDHYA +1 位作者 M.R.GOUTHAM B.V.S.MURTHY 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期41-,共1页
The dykes intruding the Hyderabad Granitic Region(HGR)which forms the part of eastern Dharwar Craton extending between northern and northwestern margins of the Cuddapah Basin and western margin of the Pakhal
关键词 southern India Part of Eastern Dharwar Craton Palaeomagnetic and Rockmagnetic Behaviour of Dykes from Hyderabad Granitic region
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Genesis and Quality of Groundwater in the Southeastern Region of Southern Vietnam
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作者 Chau Tran Vinh Tran Hong Thai +5 位作者 Doan Van Canh Dang Due Nhan Nguyen Cao Huan Nguyen Van Nghia Nguyen Hong Hieu Trinh Thi Thu Van 《Journal of Environmental Science and Engineering(A)》 2017年第6期277-292,共16页
The origin and quality of groundwater in the Southeastern region (belongs to Southern Plain) were identified by using isotopic techniques and geochemical analysis. Groundwater samples were collected from 7 aquifers... The origin and quality of groundwater in the Southeastern region (belongs to Southern Plain) were identified by using isotopic techniques and geochemical analysis. Groundwater samples were collected from 7 aquifers: the Holocene, upper Pleistocene, middle Pleistocene, lower Pleistocene, upper Pliocene, middle Pliocene and Miocene aquifers. The water isotopic compositions (82H and 8180) were determined to elucidate the origin and the interaction between surface water and groundwater studies. Transit time (age) of the groundwater samples was determined to explain the direction of groundwater flow. The dating techniques included 3H and ^14C isotopes measurement, followed by a correction for the initial ^14C-activity by the ^13C-composition (^13C) in TDIC (Total Dissolved Inorganic Carbon). Geochemical parameters of the groundwater samples were measured either directly in the field or in the laboratory. The results showed that the groundwater from the Holocene and upper Pleistocene aquifers was most recharged from the local meteorological and hydrological systems, including local precipitation, fiver and reservoirs. Thus, it has short transit time and its stable isotopic composition is spread around the local meteoric waterline and lines for rivers or reservoirs water. The groundwater in the deeper aquifers: middle and lower Pleistocene, and Neogene aquifers has old age up to 22.5 ka BP. Its water seems to be recharged from the areas with an altitude from 600 to 700 m higher to the Neogene deposit layer altitude. The groundwater in the SE SP (South-Eastern Southern Plain) region has a high quality. The water type is Na-Ca-Mg-HCO3 with low content of chloride and TDS (Total Dissolved Solids). Calcite/dolomite and gypsum dissolution, organic matter decomposition and sequence of red-ox reactions proceeding through different electron acceptors sediment were controlled the chemistry of the groundwater in the study region. 展开更多
关键词 Water isotopic composition ^14C-dating GROUNDWATER South-Eastern southern Plain region Vietnam.
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The Strength of Training and Applied Research on Specialized Sociology to Contribute to the Social Science Development(Case Study in the Southern Region of Vietnam)
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作者 Huynh Quoc Thang 《International Relations and Diplomacy》 2021年第2期89-95,共7页
With the common trend of integration and accelerated industrialization-modernization,especially in the context of the current Industrial Revolution 4.0,the South is one of the areas where there are situations and requ... With the common trend of integration and accelerated industrialization-modernization,especially in the context of the current Industrial Revolution 4.0,the South is one of the areas where there are situations and requirements especially for training and research in social sciences in general,sociology in particular.Because,the issue is not only to contribute to the early recovery of the―human resource valley‖(specializing in the South West),facilitating the rapid development of human resources for―investment policy‖and early implementation of the―zoning,planning‖but also by many other economic,social,and cultural issues of the whole region…All have been asked to promote the training and applied research in sociology,especially in specialized sociology to contribute to the linking and promoting the active role of the social sciences with strategic issues and strategies related to the practical development of this land both in the immediate future and in the long run. 展开更多
关键词 training and applied research specialized sociology southern region
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Geochemical Features of Sulfides from the Deyin-1 Hydrothermal Field at the Southern Mid-Atlantic Ridge near 15?S 被引量:3
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作者 WANG Shujie LI Huaiming +2 位作者 ZHAI Shikui YU Zenghui CAI Zongwei 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第6期1043-1054,共12页
In this study, geochemical compositions of elements in sulfide samples collected from the Deyin-1 hydrothermal field near the 15?S southern Mid-Atlantic Ridge(SMAR) were analyzed by the X-ray fluorescence spectrometry... In this study, geochemical compositions of elements in sulfide samples collected from the Deyin-1 hydrothermal field near the 15?S southern Mid-Atlantic Ridge(SMAR) were analyzed by the X-ray fluorescence spectrometry(XRF) and inductively coupled plasma mass spectrometry(ICP-MS) to examine the enrichment regulations of ore-forming elements and hydrothermal mineralization. These sulfide precipitates can be classified macroscopically into three types: Fe-rich sulfide, Fe-Cu-rich sulfide and Fe-Zn-rich sulfide, and are characterized by the enrichment of base metal elements along with a sequence of Fe>Zn>Cu. Compared with sulfides from other hydrothermal fields on MAR, Zn concentrations of sulfides in the research area are significantly high, while Cu concentrations are relatively low. For all major, trace or rare-earth elements(REE), their concentrations and related characteristic parameters exhibit significant variations(up to one or two orders of magnitude), which indicates the sulfides from different hydrothermal vents or even a same station were formed at different stages of hydrothermal mineralization, and suggests the variations of chemical compositions of the hydrothermal fluid with respect to time. The hydrothermal temperatures of sulfides precipitation decreased gradually from station TVG10(st.TVG10) to st.TVG12, and to st.TVG11, indicating that the precipitation of hydrothermal sulfides is subjected to conditions changed from high temperature to low temperature, and that the hydrothermal activity of study area was at the late stage of a general trend of evolution from strong to weak. The abnormally low concentrations of REE in sulfides and their similar chondrite-normalized REE patterns show that REEs in all sulfides were derived from a same source, but underwent different processes of migration or enrichment, or sulfides were formed at different stages of hydrothermal mineralization. The sulfides collected from the active hydrothermal vent were mainly attributed to precipitating directly from the hydrothermal fluid, while those collected from the extinct hydrothermal chimney might have already been altered by the seawater. Generally, ore-forming elements in the sulfides can be divided into three groups: Fe-based element group, Cu-based element group and Zn-based element group. The first group includes Fe, Mn, Cr, Mo, Sn, Rb and bio-enriching elements, such as P and Si, reflecting the similar characteristics to Fe in the study area. And the second group contains Cu, W, Co, Se, Te and Bi, suggesting the similar behavior with Cu. Moreover, the third group includes Zn, Hf, Hg, Cd, Ta, Ga, Pb, As, Ag, Ni and Sb, which indicates the geochemical characteristics of most dispersed trace elements controlled by Zn-bearing minerals to some extent. 展开更多
关键词 southern MID-ATLANTIC RIDGE Deyin-1 HYDROtheRMAL field HYDROtheRMAL SULFIDE geochemistry of element MINERALIZATION
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Mineralogical characteristics of polymetallic sulfides from the Deyin-1 hydrothermal field near 15°S, southern Mid-Atlantic Ridge 被引量:4
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作者 WANG Shujie LI Huaiming +3 位作者 ZHAI Shikui YU Zenghui SHAO Zongze CAI Zongwei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第2期22-34,共13页
A seafloor hydrothermal field, named Deyin-1 later, near 15°S southern Mid-Atlantic Ridge(SMAR) was newly found during the 22 nd cruise carried out by the China Ocean Mineral Resources Research & Development A... A seafloor hydrothermal field, named Deyin-1 later, near 15°S southern Mid-Atlantic Ridge(SMAR) was newly found during the 22 nd cruise carried out by the China Ocean Mineral Resources Research & Development Association(COMRA). Sulfide samples were collected at three stations from the hydrothermal field during the26 th cruise in 2012. In this paper, mineralogical characteristics of the sulfides were analyzed with optical microscope, X-ray diffractometer, scanning electron microscope and electron microprobe to study the crystallization sequence of minerals and the process of hydrothermal mineralization. According to the difference of the ore-forming metal elements, the sulfide samples can be divided into three types:(1) the Ferich sulfide, which contains mainly pyrite and chalcopyrite;(2) the Fe-Cu-rich sulfide consisting predominantly of pyrite, chalcopyrite and isocubanite, with lesser amount of sphalerite, marmatite and pyrrhotine; and(3) the Fe-Zn-rich sulfide dominated by pyrite, sphalerite and marmatite, with variable amounts of chalcopyrite, isocubanite, pyrrhotine, marcasite, galena and gratonite. Mineral precipitations in these sulfides are in the sequence of chalcopyrite(isocubanite and possible coarse pyrite), fine pyrite,sphalerite(marmatite), galena, gratonite and then the minerals out of the dissolution. Two morphologically distinct generations(Py-I and Py-II) of pyrite are identified in each of the samples; inclusions of marmatite tend to exist in the coarse pyrite crystals(Py-I). Sphalerite in the Fe-Zn-rich sulfide is characterized by a"chalcopyrite disease" phenomenon. Mineral paragenetic relationships and a wide range of chemical compositions suggest that the environment of hydrothermal mineralization was largely changing. By comparison, the Fe-rich sulfide was formed in a relatively stable environment with a high temperature, but the conditions for the formation of the Fe-Cu-rich sulfide were variable. The Fe-Zn-rich sulfide was precipitated during the hydrothermal venting at relatively low temperature. 展开更多
关键词 mineralogical characteristics mineral-forming sequence polymetallic sulfides Deyin-1 hydrothermal field southern Mid-Atlantic Ridge
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Ambient tectonic shear stress field in Southern California and seismic hazard regions 被引量:1
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作者 陈培善 肖磊 +1 位作者 白彤霞 成瑾 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第2期20-29,共10页
ccording to the fracture mechanics rupture model of earthquakes put forward by us, several equations to compute tectonic ambient shear stress value τ0 have been derived [equations (1), (2), (3), (5)].τ0 values for i... ccording to the fracture mechanics rupture model of earthquakes put forward by us, several equations to compute tectonic ambient shear stress value τ0 have been derived [equations (1), (2), (3), (5)].τ0 values for intermediate and small earthquakes occurred in Chinese mainland and Southern California have been calculated by use of these equations. The results demonstrate that the level and distribution of τ0 are closely related to the location where large earthquakes will occur, i.e. the region with higher level of τ0 will be prone to occur large earthquakes and the region with lower level will usually occur small earthquakes. According to the spatial distribution of τ0 , the seismic hazard regions or the potential earthquake source regions can in some degree be determined. According to the variation of τ0 with time, the large earthquake occurrence time can be roughly estimated. According to the distribution of τ0 in Southern California and variation with time, three high stress level regions are determined, one (Goldfield area) of them is the present seismic hazard region. 展开更多
关键词 tectonic ambient shear stress field southern California seismic hazard region potential earthquake source region
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Dynamic Simulation of Land Use in the Southern Loess Plateau 被引量:1
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作者 Bin GUO 《Asian Agricultural Research》 2014年第5期52-54,59,共4页
To study the dynamic changes of land use and predict the future land use scenarios based on the current land use,this paper uses Cellular Automata- Markov( CA- Markov) model to simulate the landscape pattern in 2030. ... To study the dynamic changes of land use and predict the future land use scenarios based on the current land use,this paper uses Cellular Automata- Markov( CA- Markov) model to simulate the landscape pattern in 2030. The results show that in the study area during the period 1980- 2005,grassland and construction land increased,and woodland increased slightly; waters and unused land decreased,and arable land underwent dramatic changes. The simulation precision of CA- Markov model is 87. 28%,indicating that the use of it for simulation is reliable. The land use of the study area will be changed greatly in the future. This method provides a reference for the regions to carry out land prediction,and the research results can provide a basis for the study of optimization of land. 展开更多
关键词 LANDSCAPE PATTERN CA-Markov RS GIS southern region
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The Impact of Current Climate Changes on Morphodynamic Regimes of Steppes and Forest Steppes in Southern Siberia
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作者 Olga Bazhenova Elizaveta Tyumentseva 《American Journal of Climate Change》 2021年第3期317-330,共14页
Predictive assessments of the geomorphological systems’ behavior under climate warming in southern Siberia have been performed based on time-series data, using theoretical and empirical models of processes. High sens... Predictive assessments of the geomorphological systems’ behavior under climate warming in southern Siberia have been performed based on time-series data, using theoretical and empirical models of processes. High sensitivity and fast response of erosional, aeolian, and cryogenic processes to current climatic changes are presented. The current trends under changing functioning conditions of geomorphological systems while maintaining climatic trends have been determined. Areas with different targeting of morpholithogenesis are identified. 展开更多
关键词 Climatic Trends Relief Formation Trends Morphoclimatic regions southern Siberia STEPPES
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The Relation Between Tourism, Local Development and Insularity: Case Study of Southern Aegean, Greece
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作者 Christos Pallis Andreas Prasinos Petros Pallis 《Journal of Tourism and Hospitality Management》 2017年第6期223-232,共10页
Greece as a significant tourist destination showed a considerable increase (5.1%) in tourist arrivals in 2016, despite intense geopolitical upheaval, especially in the area of South-East Aegean. It is noteworthy tha... Greece as a significant tourist destination showed a considerable increase (5.1%) in tourist arrivals in 2016, despite intense geopolitical upheaval, especially in the area of South-East Aegean. It is noteworthy that the main volume of tourism proceeds in Greece was generated by its insular regions, despite the intense problems faced by insularity, and by the insular Region of Southern Aegean in particular, despite the heavy refugee flows due to its geopolitical position. However, how is insularity affected by the new hyper-taxation of the islands through the increase of value added tax in insular local development and tourism? Is insular economy strong enough to withstand the increased and intensely varying international challenges? In this paper, after realistically depicting the official and published national tourism results for 2016, it is presented the immediate policy, institutional and destination management actions required in the Region of Southem Aegean so that it might be able to respond adequately to the new European or global tourism challenges, and act as the steam engine of the Greek tourism, pulling the broader Greek tourism development forward. 展开更多
关键词 INSULARITY destination management TOURISM region of southern Aegean Greece
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Form and Image Expression of Traditional Village Texture in Southern Hebei
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作者 YANG Caihong MENG Chao LIU Huixin 《Journal of Landscape Research》 2022年第2期48-50,54,共4页
The image expression of traditional villages is studied through the analysis of their forms.With the famous historical and cultural villages in southern Hebei as the research objects,the relationship between the form ... The image expression of traditional villages is studied through the analysis of their forms.With the famous historical and cultural villages in southern Hebei as the research objects,the relationship between the form and image of traditional villages is deeply analyzed through the survey of village layout and courtyard layout,which can deeply explain the characteristics of regional architectural culture. 展开更多
关键词 Traditional village Layout form Image expression southern Hebei region
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Extensive Cold-Precipitation-Freezing Events in Southern China and Their Circulation Characteristics 被引量:6
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作者 Jing-Bei PENG Cholaw BUEH Zuo-Wei XIE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第1期81-97,共17页
Concurrence of low temperature,precipitation and freezing weather in an extensive area would cause devastating impacts on local economy and society.We call such a combination of concurrent disastrous weather“extensiv... Concurrence of low temperature,precipitation and freezing weather in an extensive area would cause devastating impacts on local economy and society.We call such a combination of concurrent disastrous weather“extensive coldprecipitation-freezing”events(ECPFEs).In this study,the ECPFEs in southern China(15°−35°N,102°−123°E)are objectively defined by using daily surface observational data for the period 1951−2013.An ECPFE in southern China is defined if the low temperature area,precipitation area and freezing area concurrently exceed their respective thresholds for at least three consecutive days.The identified ECPFEs are shown to be reasonable and reliable,compared with those in previous studies.The circulation anomalies in ECPFEs are characterized by a large-scale tilted ridge and trough pairing over mid-and high-latitude Eurasia,and the intensified subtropical westerlies along the southern foot of the Tibetan Plateau and the anomalous anticyclonic circulation over the subtropical western Pacific.Comparative analysis reveals that the stable cold air from the north and the warm and moist air from the south converge,facilitating a favorable environment for the concurrence of extensive low-temperature,precipitation and freezing weather. 展开更多
关键词 extensive cold-precipitation-freezing event southern China large-scale tilted ridge and trough trough over the Bay of Bengal western Pacific subtropical high
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