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Diatom assemblages in surface sediments from the South China Sea as environmental indicators 被引量:1
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作者 吴瑞 高亚辉 +4 位作者 方琦 陈长平 兰彬斌 孙琳 蓝东兆 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第1期31-45,共15页
We studied diatom distribution from 62 samples from the uppermost 1 cm of sedimem in the South China Sea (SCS), using grabs or box corers in three cruises between 2001-2007. Fifty six genera, 256 species and their v... We studied diatom distribution from 62 samples from the uppermost 1 cm of sedimem in the South China Sea (SCS), using grabs or box corers in three cruises between 2001-2007. Fifty six genera, 256 species and their varieties were identified. Dominating species included Coscinodiscus africanus, Coscinodiscus nodulifer, Cyclotella stylorum, Hemidiscus cuneiformis, Melosira sulcata, Nitzschia marina, Roperia tesselata, Thalassionema nitzschioides, Thalassiosira excentrica, and Thalassiothrix longissima. Most surface sediments in the SCS were rich ill diatoms, except for a few coarse samples. Average diatom abundance in the study area was 104 607 valve/g. In terms of the abundance, ecology, and spatial distribution, seven diatom zones (Zones 1-7) were recognized. Zone 1 (northern continental shelf) is affected by warm currents, SCS northern branch of the Kuroshio, and northern coastal currents; Zone 2 (northwestern continental shelf) is affected by intense coastal currents; Zone 3 (Xisha Islands sea area) is a bathyal environment with transitional water masses; Zone 4 (sea basin) is a bathyal-to-deep sea with stable and uniform central water masses in a semi-enclosed marginal sea; Zone 5 (Nansba Islands marine area) is a pelagic environment with relatively high surface temperature; Zone 6 (northern Sunda Shelf) is a tropical shelf environment; and Zone 7 (northern Kalimantan Island shelf area) is affected by warm waters from the Indian Ocean and coastal waters. The data indicate that these diatom zones are closely related to topography, hydrodynamics, temperature, nutrients and especially the salinity. Better understanding of the relationship between diatom distribution and the oceanographic factors would help in the reconstruction of the SCS in the past. 展开更多
关键词 surface sediments diatom assemblage zones environmental factors South China Sea (SCS)
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Vertical patterns in plant diversity and their relations with environmental factors on the southern slope of the Tianshan Mountains(middle section)in Xinjiang(China) 被引量:17
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作者 LIU Bin 《Journal of Mountain Science》 SCIE CSCD 2017年第4期742-757,共16页
The investigation of distribution patterns of species diversity is significant for successful biodiversity conservation. The spatial patterns of vegetation and different life-forms species diversity along an elevation... The investigation of distribution patterns of species diversity is significant for successful biodiversity conservation. The spatial patterns of vegetation and different life-forms species diversity along an elevation gradient in the middle section of the southern slope of the Tianshan Mountains in Xinjiang, China were explored, using the detrended canonical correspondence analysis (DCCA) and the generalized additive model (GAM) methods based on a field survey of 53 sampling plots. In this work 158 species of seed plants were recorded, including 141 herbaceous, 14 shrub, and 2 tree species, in which the woody plants are very limited. 53 sampling plots were classified into 9 major plant communities. The results indicate that the herb communities were the most sensitive to changes in elevation gradient. The diversity indices of the community as a whole presented bimodal patterns. The peak values for the species diversities were found in the transition region between mountain steppe desert and mountain desert steppe (2,200-2,300m), and in the alpine grassland region (2,900-3,100m), while maximum species diversities were in the areas of intermediate environmental gradient. The main environmental factors on the distribution patterns in plant diversity were the elevation, soft water, total nitroeen, available nitrogen, organic matter, and total salt. The response tendency of the four diversity indices for the whole community to the soil environment was the same as that of the herb layers. 展开更多
关键词 Species diversity Distribution pattern Plant community Soil properties Tianshan Mountains
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Wind Wave Characteristics and Engineering Environment of the South China Sea 被引量:4
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作者 WANG Zhifeng ZHOU Liangming +4 位作者 DONG Sheng WU Lunyu LI Zhanbin MOU Lin WANG Aifang 《Journal of Ocean University of China》 SCIE CAS 2014年第6期893-900,共8页
Wave simulation was conducted for the period 1976 to 2005 in the South China Sea (SCS) using the wave model, WAVEWATCH-III. Wave characteristics and engineering environment were studied in the region. The wind input... Wave simulation was conducted for the period 1976 to 2005 in the South China Sea (SCS) using the wave model, WAVEWATCH-III. Wave characteristics and engineering environment were studied in the region. The wind input data are from the objective reanalysis wind datasets, which assimilate meteorological data from several sources. Comparisons of significant wave heights between simulation and TOPEX/Poseidon altimeter and buoy data show a good agreement in general. By statistical analysis, the wave characteristics, such as significant wave heights, dominant wave directions, and their seasonal variations, were discussed. The largest significant wave heights are found in winter and the smallest in spring. The annual mean dominant wave direction is northeast (NE) along the southwest (SW)-NE axis, east northeast in the northwest (NW) part of SCS, and north northeast in the southeast (SE) part of SCS. The joint distributions of wave heights and wave periods (directions) were studied. The results show a single peak pattern for joint significant wave heights and periods, and a double peak pattern for joint significant wave heights and mean directions. Furthermore, the main wave extreme parameters and directional extreme values, particularly for the 100-year return period, were also investigated. The main extreme values of significant wave heights are larger in the northern part of SCS than in the south- ern part, with the maximum value occurring to the southeast of Hainan Island. The direction of large directional extreme Hs values is focus in E in the northem and middle sea areas of SCS, while the direction of those is focus in N in the southeast sea areas of SCS. 展开更多
关键词 surface waves statistical characteristics joint distributions extreme parameters
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Neoproterozoic stratigraphic correlation of Subei-Huainan in China 被引量:1
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作者 刘为付 刘双龙 +3 位作者 孙立新 白文爽 丁振坤 王泽宇 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第6期1449-1458,共10页
Subei-Huainan in the southeastern margin of the North China platform is a key area of convergence of China’s north-south stratigraphic correlation of Neoproterozoic.Due to the lack of fossils,the Neoproterozoic strat... Subei-Huainan in the southeastern margin of the North China platform is a key area of convergence of China’s north-south stratigraphic correlation of Neoproterozoic.Due to the lack of fossils,the Neoproterozoic stratigraphic correlation is still a difficulty in this area.The division of Neoproterozoic strata and the establishment of the correlation framework of the stratigraphic sequences have been done through recognizing the regularity of meter-scale cycles by measuring the outcrop of Neoproterozoic strata and using the Fischer diagram and the sea-level curve of transgressive-regressive by the maximum flooding sedimentary and molar teeth carbonate sedimentary.The maximum flooding sedimentary which becomes cycle sequence comparison of sign is isochronous in the same basin and is a key of cycle sequence comparison although paleogeographic environment and sedimentary sequence may be different in the sedimentary strata of the same geologic time.Molars carbonates,having specific geological distrution time and depositional environment and mainly developing in the ramp environment of the platform edge in the 1500-650 Ma,are the new symbol of the stratigraphic correlation in the Neoproterozoic.Because of the missing of the fossil record,the maximum flooding and the molar-teeth carbonate sedimentary,as the new research ideas,are used in stratigraphic division and correlation. 展开更多
关键词 Fischer diagram sea-level change molar-teeth carbonate maximum flooding sedimentary NEOPROTEROZOIC Subei-Huainan
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Hydrodynamic Comparison of a Semi-submersible,TLP,and Spar:Numerical Study in the South China Sea Environment 被引量:5
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作者 Binbin Li Kun Liu +1 位作者 Gongwei Yan Jinping Ou 《Journal of Marine Science and Application》 2011年第3期306-314,共9页
The South China Sea contains tremendous oil and gas resources in deepwater areas. However, one of the keys for deepwater exploration, the investigation of deepwater floating platforms, is very inadequate. In this pape... The South China Sea contains tremendous oil and gas resources in deepwater areas. However, one of the keys for deepwater exploration, the investigation of deepwater floating platforms, is very inadequate. In this paper, the authors studied and compared the hydrodynamics and global motion behaviors of typical deepwater platforms in the South China Sea environment. The hydrodynamic models of three main types of floating platforms, e.g. the Semi-submersible, tension leg platform (TLP), and Truss Spar, which could potentially be utilized in the South China Sea, were established by using the 3-D potential theory. Additionally, some important considerations which significantly influence the hydrodynamics were given. The RAOs in frequency domains as well as global motions in time domains under time-varying wind, random waves, and current in 100-y, 10-y, and 1-y return period environment conditions were predicted, compared, and analyzed. The results indicate that the heave and especially the pitch motion of the TLP are favorable. The heave response of the Truss Spar is perfect and comparable with that of the TLP when the peak period of random waves is low. However, the pitch motion of Truss Spar is extraordinarily lar^er than that of Semi-submersible and TLP. 展开更多
关键词 SEMI-SUBMERSIBLE Spar tension leg platform (TLP) South China Sea HYDRODYNAMICS
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SURFACE OBSERVATIONS IN THE TROPICAL CYCLONE ENVIRONMENT OVER THE SOUTH CHINA SEA 被引量:1
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作者 刘春霞 万齐林 +1 位作者 廖菲 赵中阔 《Journal of Tropical Meteorology》 SCIE 2012年第2期263-274,共12页
In this paper, the observational data from Marine and Meteorological Observation Platform (MMOP) at Bohe, Maoming and buoys located in Shanwei and Maoming are used to study the characteristics of air-sea temperature... In this paper, the observational data from Marine and Meteorological Observation Platform (MMOP) at Bohe, Maoming and buoys located in Shanwei and Maoming are used to study the characteristics of air-sea temperature and specific humidity difference and the relationship between wind and wave with the tropical cyclones over the South China Sea (SCS). The heat and momentum fluxes from eddy covariance measurement (EC) are compared with these fluxes calculated by the COARE 3.0 algorithm for Typhoon Koppu. The results show that at the developing and weakening stages of Koppu, both these differences between the sea surface and the near-surface atmosphere from the MMOP are negative, and data from the buoys also indicate that the differences are negative between the sea surface and near-surface atmosphere on the right rear portion of tropical cyclones (TCs) Molave and Chanthu. However, the differences are positive on the left fi'ont portion of Molave and Chanthu. These positive differences suggest that the heat flux is transferred from the ocean to the atmosphere, thus intensifying and maintaining the two TCs. The negative differences indicate that the ocean removes heat fluxes from the atmosphere, thus weakening the TCs. The wind-wave curves of TCs Molave and Chanthu show that significant wave height increases linearly with 2-min wind speed at 10-m height when the wind speed is less than 25 m/s, but when the wind speed is greater than 25 m/s, the significant wave height increases slightly with the wind speed. By comparing the observed sensible heat, latent heat, and friction velocity from EC with these variables from COARE 3.0 algorithm, a great bias between the observed and calculated sensible heat and latent heat fluxes is revealed, and the observed friction velocity is found to be almost the same as the calculated friction velocity. 展开更多
关键词 tropical cyclones over the South China Sea temperature and specific humidity difference wind-wave
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Human Driving Forces:Analysis of Rocky Desertification in Karst Region in Guanling County,Guizhou Province 被引量:20
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作者 WU Xiuqin LIU Hongmeng +1 位作者 HUANG Xiulan ZHOU Tao 《Chinese Geographical Science》 SCIE CSCD 2011年第5期600-608,共9页
Karst rocky desertification is one of the major ecological and environmental problems that threaten the sustainable development of southwestern China. It is caused by irrational and intensive land-use patterns in kars... Karst rocky desertification is one of the major ecological and environmental problems that threaten the sustainable development of southwestern China. It is caused by irrational and intensive land-use patterns in karst geo-ecological environment. Therefore, it is vital to identify how human forces work on this degraded environment. Based on the soil erosion information in 2000 and remote sensing images of Guanling County collected in 2000 and 2007, four grades of karst rocky desertification data in 14 villages of Guanling County were extracted. Impacts of population, affluence, and other human forces on karst rocky desertification were analyzed using STIRPAT model. The results show that:1) Factors of population and affluence had strong influence on karst rocky desertification. In the STIRPAT model analysis, the population and affluence coefficients were positive, indicating that the increase in population and affluence would lead to more serious desertification. 2) Factors of farmer correlated with karst rocky desertification negatively, especially the way of viewing the relationship between people and nature, and the level of knowledge about rocky desertification. Government behavior was not a significant factor in this analysis. 3) The findings provide evidence that STIRPAT model can be used to analyze the relationship between human driving forces and rocky desertification. 展开更多
关键词 karst rocky desertification human driving forces STIRPAT model Guanling County Guizhou Province
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FEATURES OF SPERMATOPHYTIC FLORA OF HENAN PROVINCE IN CHINA
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作者 ZHANGGui-bin 《Chinese Geographical Science》 SCIE CSCD 2005年第1期47-51,共5页
Based on the latest data, the features of spermatophytic flora of Henan Province located in Central China Plain (the heart region of China) are summarized and demonstrated in this paper. They are as follows: 1) Plant ... Based on the latest data, the features of spermatophytic flora of Henan Province located in Central China Plain (the heart region of China) are summarized and demonstrated in this paper. They are as follows: 1) Plant species are rich, with 2953 wild species in 896 genera of 152 families, putting Henan in front rank in the northern areas of China. 2) Its origin is from far ancientry, and there exist many primitive families and genera as well as many relic species. 3) The character of transition is very conspicuous with complex and varied geographical elements, but the temperate type being the dominant. There are 15 types and 18 variants of distribution types at the genera level, the typical Temperate, Tropic and East Asia elements respectively make up 47.9%, 29.5% and 14.5%. 4) It is rich in species endemic to China, with 1514 species, ranking first in the northern areas in China. 5) The floristic spatial differentia is obvious. The southeastern Henan belongs to East China plant region, the southwestern to Central China, the northern and the central to North China. 展开更多
关键词 spermatophyte floristic characteristics Henan Province in China
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Study on The Music Culture of Cribwork Song of Kangxian County,Longnan City of China
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作者 Zheng Xiuling 《International Journal of Technology Management》 2016年第10期18-20,共3页
Cribwork Song is a long narrative folk song,which spread in the folk of Kangxian County,Longnan City,Gansu Province of China.This paper has analyzed historical background,humanistic environment,story plot,artistic cha... Cribwork Song is a long narrative folk song,which spread in the folk of Kangxian County,Longnan City,Gansu Province of China.This paper has analyzed historical background,humanistic environment,story plot,artistic characteristic and inheritance significance of Cribwork Song. 展开更多
关键词 Cribwork Song of Kangxian County Hua Erjie LYRIC MUSIC INHERIT
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Research on the environmental trace elements in permian coals and their ashes from Huainan coalmine area,China
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作者 LIU Wen-zhong CHEN Ping KONG Wei-hui 《Journal of Coal Science & Engineering(China)》 2010年第3期306-310,共5页
The contents of environmental trace elements in permian coal from Huainancoalmine area and their combustion products were tested by ICP-MS.Analysis and comparativeresearches on the contents of eighteen environmental t... The contents of environmental trace elements in permian coal from Huainancoalmine area and their combustion products were tested by ICP-MS.Analysis and comparativeresearches on the contents of eighteen environmental trace elements in coal andits combustion product suggest that Se and Cd have a high level of distribution in coals;As, Se, Cd, Sb and As, Se, Cd, Mo, Be, Sb also have a high level of distribution in 815 ℃and 1 100 ℃ coal ashes, respectively.Combustion temperature, thermodynamics featuresof trace elements and ash content in coal are the main factors that influence theabundance of trace elements in coal and ash. 展开更多
关键词 permian coal coal ash trace element
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Differentiation and restructuring-new space for development of urban center area:a case study of Shizhong District of Ji'nan City
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作者 Shi Xiaoyan Wu Meichuang 《Ecological Economy》 2009年第3期248-258,共11页
Taking the development tendency of current world industrial development as the background, this paper restructures the internal space of urban center area by illustrating reasons for internal space differentiation of ... Taking the development tendency of current world industrial development as the background, this paper restructures the internal space of urban center area by illustrating reasons for internal space differentiation of urban center area, that is to say, according to the tertiary industry interior's high-end of value chain after convergence among the primary, the secondary and the tertiary industries, the space structure of urban center area will form the space development mode with characteristic modern service industry cluster districts through vertical segmentation, horizontal derivatization and block aggregation and realize perfect space renewal of urban center area in the end. 展开更多
关键词 Urban center area DIFFERENTIATION RESTRUCTURING Shizhong District Ji'nan
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The paleoclimate environment and recent sea level change on the seashores of Thailand Gulf in Southeast Asia
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作者 Hu Dongsheng Li Xiaoyu +2 位作者 Pang Xilei Tian Xinhong Zhang Guowei 《Engineering Sciences》 EI 2014年第1期51-58,共8页
This paper analyzed and researched on several significant natural geological sections from the views of stratum-sequence stratigraphy,climate stratigraphy,event stratigraphy and regional stratigraphy by the investigat... This paper analyzed and researched on several significant natural geological sections from the views of stratum-sequence stratigraphy,climate stratigraphy,event stratigraphy and regional stratigraphy by the investigation of Thailand,Malaysia and Singapore. In combination with the coupling relationship between the life-temperature of regional life zone and the evolution of geological environment,this paper exactly made out the geological sediment records of paleoclimate times in different time scales of 3 kaBP,1 kaBP and 0.5 kaBP since the past glacier age of Quaternary period,and it is consecutive and authentic for the material medium and time joint. These studies definitely reflected that the sea level of Thailand Gulf area is in tendency of continually dropping in recent years. They also provided important and new information for the global change analysis. 展开更多
关键词 recent sea level change natural geological section global change Thailand Gulf in Southeast Asia
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英雄时代的心灵诉说——唐大禧雕塑及《塑说》的文化意义 被引量:1
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作者 江冰 《文艺争鸣》 CSSCI 北大核心 2010年第6X期86-89,共4页
唐大禧的雕塑创作历程是"颂歌时代"的产物,但在寓时代风云的同时,他也有内心的挣扎和真情的流露。也正是在这个意义上,沈平的作品解读具有文化意义。
关键词 唐大禧雕塑 南国环境 英雄情结 艺术家评传
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Coral reefs in the South China Sea:Their response to and records on past environmental changes 被引量:47
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作者 YU KeFu 《Science China Earth Sciences》 SCIE EI CAS 2012年第8期1217-1229,共13页
This paper reviews both the recent and longer-term (Holocene) ecological history of coral reefs in the South China Sea (SCS). (1) Local ecological monitoring since the 1960s shows that the coral reefs in the Sou... This paper reviews both the recent and longer-term (Holocene) ecological history of coral reefs in the South China Sea (SCS). (1) Local ecological monitoring since the 1960s shows that the coral reefs in the South China Sea have declined dramatically, reflecting the rapid decrease of living coral cover and the great loss of symbiotic zooxanthellae. Collectively, this has led to a significant decrease of annual CaCO3 production. Heavy anthropogenic activities and global warming are recognized as major triggers of the observed coral reef degradation. Observations show that the modern coral reefs in the SCS are a source of at- mospheric CO2 in summer. (2) Coral reefs of the SCS have been widely used to reveal longer-term environmental variations, including Holocene high-resolution sea surface temperature (SST) and abrupt climate events, millennial-scale E1 Nifio varia- tions, millennial- and centennial-scale sea level oscillations, strong and cyclic storm activities, East Asian monsoon intensities, variation in seawater pH, and recent seawater pollution. (3) Coral reefs of the southern SCS have experienced repeated epi- sodes of bleaching over the last 200 years due to high SST and intense E1 Nino events; coral reefs of the northern SCS suffered high levels of mortality during several abrupt winter cold-water bleaching events during the middle Holocene warm period. On average, recovery after the middle Holocene cold-bleaching took 20-30 years; recovery following other middle Holocene en- vironmental stresses took approximately 10-20 years. Such findings have significantly contributed to the understanding of the present ecological pressures faced by the coral reefs in the SCS, the histories of Holocene climate/environment changes, and the long-term models of coral reef responses to various past environmental changes. 展开更多
关键词 coral reefs ECOLOGY environment climate Hoiocene South China Sea
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The growth of the screw dislocation of nacreous layer on Pteria penguin 被引量:3
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作者 QI LiJian HUANG YiLan +1 位作者 ZHOU ZuYi ZHOU ZhengYu 《Science China Earth Sciences》 SCIE EI CAS 2011年第7期951-958,共8页
In response to various environmental factors in offshore South China Sea,a group of microstructures of the screw dislocation are assembled in multiphase screw dislocations on the surface of the nacreous layer of Pteri... In response to various environmental factors in offshore South China Sea,a group of microstructures of the screw dislocation are assembled in multiphase screw dislocations on the surface of the nacreous layer of Pteria penguin from the coastal waters of Hainan Island,China.The results of the transmission and scanning electronic microscope testing show that organic matter periodically secreted by epithelial histology of mantle of Pteria penguin pre-forms the original screw dislocation growth tem-plate in the form of film,along with its function to select,identify,and adhere to the amorphous calcium carbonate particles as the fine organic venations diffused in the epitaxial screw growth area.With the inducement and screw modulation of the or-ganic film and venations,the amorphous calcium carbonate particles gradually evolve into the pseudohexagonal self.aragonite microsheet with long-range order and screw dislocation structure by location-selecting tropism and screw dislocation growth.Numerous micron-scale aragonite microsheets join in the cluster's interactive movement and screw dislocation self-assembly of the organic film,stacking forward along the axis C spirally and forming the nacreous layer with screw dislocation structure. 展开更多
关键词 Pteria penguin nacreous layer organic film aragonite micro sheet screw dislocation
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Fossil seeds of Euryale(Nymphaeaceae) indicate a lake or swamp environment in the late Miocene Zhaotong Basin of southwestern China 被引量:4
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作者 Yongjiang Huang Xueping Ji +5 位作者 Tao Su Li Wang Chenglong Deng Wenqi Li Hongfen Luo Zhekun Zhou 《Science Bulletin》 SCIE EI CAS CSCD 2015年第20期1768-1777,共10页
Euryale (Nymphaeaceae) is a monotypic genus distributed in eastern Asia, but fossils in its native distribu- tion are sparse as compared to Europe where the genus has disappeared. Here, we describe a new fossil spec... Euryale (Nymphaeaceae) is a monotypic genus distributed in eastern Asia, but fossils in its native distribu- tion are sparse as compared to Europe where the genus has disappeared. Here, we describe a new fossil species, Euryale yunnanensis sp. nov., from the late Miocene Zhaotong Basin in southwestern China on the basis of seed remains. Char- acteristics including an ellipsoidal to almost spherical shape, a smooth surface, a germination cap that covers the micro- pyle, the separation of the hilum and germination cap (mi- cropyle), elliptic testa surface cells with undulate margins and thickened cell walls collectively indicate a close affinity with the genus Euryale in Nymphaeaceae. Comparisons of seed morphology and anatomy demonstrate that the newly described fossil species differs from modem and other fossil species of Euryale and thus verify the assignment to a new fossil species. As the modem Euryale is an aquatic plant, preferably living in swamps and lakes with shallow and stable water, we hypothesize that a lake and/or swamp environment with shallow water was present near Shui- tangba in the Zhaotong Basin, where the Shuitangba homi- noid lived during the late Miocene. This inference is generally consistent with paleoenvironmental data extracted from avian, fish, frog, turtle and crocodile fossils, as well as from aquatic pollen. The fossil history suggests a compara- tively recent (Miocene) emergence of Euryale, which is roughly in agreement with the divergence time inferred from the molecular information. 展开更多
关键词 Euryale NYMPHAEACEAE AQUATIC Late Miocene Zhaotong Basin Southwestern China
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Community replacement sequences and paleoenvironmental changes in reef areas of South China from Late Permian to Early Triassic exemplified by Panlongdong section in northeastern Sichuan Basin 被引量:4
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作者 LIU LiJing JIANG HongXia +1 位作者 WU YaSheng CAI ChunFang 《Science China Earth Sciences》 SCIE EI CAS 2014年第5期1093-1108,共16页
The well-known Permian Changhsingian calcisponge reef located at Panlongdong section,Xuanhan county,northeastern Sichuan Basin has attracted wide attention.Due to severe dolomitization and poor quality of the fossils,... The well-known Permian Changhsingian calcisponge reef located at Panlongdong section,Xuanhan county,northeastern Sichuan Basin has attracted wide attention.Due to severe dolomitization and poor quality of the fossils,the P-T boundary in this section is difficult to determine.This study,for the first time,recognized six communities in the Upper Permian Changhsingian Changxing Formation through the Lower Triassic Induan Feixianguan Formation of the Panlongdong section.They are Bryozoan-Archaeolithoporella-calcisponge Community,Calcareous green algae-foraminifer-crinoid Community,Microgastropod-foraminifer Community,Ostracod-microgastropod-cystic microbe Community,Ostracod-small brachiopod Community,and Non-calcified cyanobacteria Community.By using community replacement and palaeoenvironmental analysis,for the first time,we set the P-T boundary of the Panlongdong section at the middle of the calcimicrobialite containing cystic microbes.The community replacement sequence in the Panlongdong section is similar to that in other contemporaneous sections in reef areas of South China,indicating universal palaeoenvironmental changes during the Permian-Triassic transition.The results show that:(1)Changhsingian calcisponge reefs in South China generally vanished before the mass extinction and may be related to the large regression in the Late Permian.(2)The Calcareous green algae-foraminifer-crinoid Community replaced reef community and continued till the mass extinction.The mass extinction was probably related to the global sea-level drop.(3)The first aftermath community was dominated by specialized microgastropods,followed by the microbes,and then by the specialized microgastropods and small brachiopods.The succession of the three communities reflected the change in environmental conditions from dysoxic to anoxic and again to dysoxic.(4)In the Early Triassic,the relict community in shallow sea had very low diversity and low abundance,and was dominated by crinoids,gastropods,and bivalves. 展开更多
关键词 Panlongdong Permian-Triassic boundary mass extinction community replacement sequences paleoenvironmentalchanges South China sea-level drop
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Distribution of living radiolarians in spring in the South China Sea and its responses to environmental factors 被引量:4
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作者 HU WeiFen ZHANG LanLan +5 位作者 CHEN MuHong ZENG LiLi ZHOU WeiHua XIANG Rong ZHANG Qiang LIU ShiHao 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第2期270-285,共16页
Using a planktonic net(62-?m mesh) and a Rose-Bengal staining method, we studied the spatial distribution of living radiolarians in spring along two sections of the South China Sea(SCS) in spring and discussed the res... Using a planktonic net(62-?m mesh) and a Rose-Bengal staining method, we studied the spatial distribution of living radiolarians in spring along two sections of the South China Sea(SCS) in spring and discussed the responses of living radiolarian distribution to tropical environmental factors. Generally, the highest abundance of living radiolarians occurred at the depth range of 25–75 m, where the chlorophyll-a maximum and the highest primary productivity were. In contrast, the maximum living abundance occurred in the top 25 m in cold eddies in the open seas and the abundance decreased with depth. We found that the inhibition effect of changing salinity(due to runoffs) on living radiolarians was much stronger than the promotion effect of mesoscale cold eddies. We observed that large variation of temperature was unfavorable for living radiolarians. The dominant species composition consisted of tropical-subtropical warm species. We identified some indicator species for tropical environments. Living Didymocyrtis tetrathalamus tetrathalamus could be an indicator for tropical surface water or mixed-layer water, and even for tropical oligotrophic water. Living Tetrapyle octacantha could be used to indicate tropical thermocline and eutrophic environment. Living Acanthodesmia vinculata could indicate tropical surface and subsurface waters. T. octacantha and A. vinculata should only be used as indicators for upwelling in the open seas, i.e., far away from river mouths. Living Siphonosphaera polysiphonia preferred to form colonies, which might be related to the effect of warm eddies. Living Cyrtopera laguncula and living Cornutella profunda occurred in the tropical upper layer, even in the surface layer, which suggests that they should not be used as indicators for intermediate and deep waters. 展开更多
关键词 tropical mesoscale abundance indicator salinity chlorophyll sections stronger Figure environments
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Opportunity Cost or Opportunity Lost: The Humanities in South Africa
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作者 Peter Vale 《Fudan Journal of the Humanities and Social Sciences》 2011年第4期56-78,共23页
By positioning the debate on the future of the Humanities in an international setting, this essay presents an historical and contemporary account of them in South Africa. [ In this country the Humanities and the Socia... By positioning the debate on the future of the Humanities in an international setting, this essay presents an historical and contemporary account of them in South Africa. [ In this country the Humanities and the Social Sciences are subsumed under a single (and rather imperfect ) organizational rubric ]. The argument looks at the role they played during apartheid and their influence in bringing apartheid to an end. In the post-apartheid period the Humanities have fallen on hard times with less funding and failing student numbers. In this, South Africa follows the international trend but two enquiries into the future of the Humanities have opened space for a deep conversation on their future. 展开更多
关键词 HUMANITIES social science UNIVERSITY CRISIS South Africa
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