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An approach to the influence of industrial structure on urban ecological environment
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作者 Cui Fengjun Ru Jiang Xu Yunlin(Center for Environmental Sciences, Peking University, Beijing 100871, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1994年第4期440-448,共9页
dustrial structure is key link of man's action to ecological environmental system. Its combina-tion type and intensity determine, to a great extent, economic benefit, resources utilization efficiency andstress on ... dustrial structure is key link of man's action to ecological environmental system. Its combina-tion type and intensity determine, to a great extent, economic benefit, resources utilization efficiency andstress on environment. So the assessment to the rationality of industrial structure is of great importance. Inpresent paper, the research theories and ways on relationship between industrial structure and ecological en-vironmental systems were put forward. Environmental carrying capacity (ECC) was adopted to describequantitatively the relationship between man's social economic activity and environmental resources. At theend of this paper. analysis was made with Benxi City as an example. 展开更多
关键词 industrial structure ecological environmental system environmental carrying capacity BenxiCity.
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Community structure and spatial-temporal variation of netzphytoplankton in the Bering Sea in summer
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作者 WANG Yu XIANG Peng +4 位作者 YE Youyin LIN Gengming YANG Qingliang LIN Heshan LIN Mao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第4期99-107,共9页
Marine biodiversity is changing in response to altered physical environment, subsequent ecological changes as well as anthropogenic disturbances. In this study, phytoplankton samples in situ collected in the Bering Se... Marine biodiversity is changing in response to altered physical environment, subsequent ecological changes as well as anthropogenic disturbances. In this study, phytoplankton samples in situ collected in the Bering Sea in July of 1999 and 2010 were analyzed to obtain phytoplankton community structure and spatial-temporal variation between the beginning and end of this decade, and the correlation of phytoplankton community dynamics and environmental factors was investigated. A total of 5 divisions, 58 genera and 153 species of phytoplankton belonging to 3 ecological groups were identified. The vast majority of phytoplankton consisted of diatoms accounting for 66.7% of the total species and 95.2% of the total abundance. Considering differentiation in spatial extent and phytoplankton sample types, there were subtle changes in species composition, large altering in abundance and significant variation in spatial distribution between two surveys. The abundance peak area was located at the Bering Strait while sub peak was found at the Bering Sea Basin. The boreal-temperate diatom was the dominant flora, which was subsequently replaced by eurythermal and frigid-water diatom. Phytoplankton community in the Bering Sea was not a simplex uniform community but composed of deep-ocean assemblage and neritic assemblage. The deep-ocean assemblage was located in the northwestern Pacific Ocean and Bering Sea Basin, dominated by boreal-temperate species(Neodenticula seminae, Thalassiothrix longissima, Amphiprora hyperborean, Chaetoceros atlanticus, Thalassiosira trifulta, etc.) and eurychoric species(Thalassionema nitzschioides, Ch. compressus, Rhizosolenia styliformis, etc.), and characterized by low abundance, even interspecies abundance allocations, diverse dominant species and high species diversity. The neritic assemblage was distributed on the continental shelf and slope of Bering Sea and was mainly composed of frigid-water species(Th.nordenski?ldii, Ch. furcellatus, Ch. socialis, Bacteriosira fragilis, etc.) and eurythermal and euryhaline species(L.danicus, Ch. curvisetus, Coscinodiscus curvatulus, etc.), and it was characterized by high abundance, uneven interspecies allocations, prominent dominant species and low species diversity. Spatial-temporal variation of species composition and abundance of phytoplankton in the Bering Sea was directly controlled by surface circulation,nutrient supply and ice edge. 展开更多
关键词 Bering Sea phytoplankton community structure spatial and temporal variation distribution environment changes
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Community characteristics of macrobenthos in the Huanghe(Yellow River) Estuary during water and sediment discharge regulation 被引量:2
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作者 REN Zhonghua LI Fan +4 位作者 WEI Jiali LI Shaowen LV Zhenbo GAO Yanjie CONG Xuri 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第8期74-81,共8页
The community characteristics of macrobenthos in the Huanghe(Yellow River) Estuary is influenced by a combination of natural and anthropogenic factors. Here, we investigated short-term changes(1-month) in macroben... The community characteristics of macrobenthos in the Huanghe(Yellow River) Estuary is influenced by a combination of natural and anthropogenic factors. Here, we investigated short-term changes(1-month) in macrobenthic community structure in response to water and sediment discharge regulation(WSDR) in 2011.Specifically, we sampled the macrobenthos at 18 sampling stations situated at four distances(5, 10, 20, and 40 km)from the mouth of the Huanghe Estuary before(mid-June), during(early-July), and after(mid-July) WSDR. The results showed that a total of 73, 72, and 85 species were collected before, during, and after WSDR, respectively.Then, 13, 1, and 16 dominant species were detected at this three periods. Four phyla were primarily detected at all three periods(Annelida, Mollusca, Arthropoda, and Echinodermata). However, while Mollusca and Annelida were the most important phyla in our study, Echinodermata and Annelida were the most important phyla in 1982,demonstrating major changes to community structure over a 3-decadal period. All stations were of high quality BOPA index before WSDR, whereas two and three stations were of reduced quality BOPA index during and after WSDR, respectively. The results of ABC curves showed that had incurred disturbed conditions after human activities WSDR. Most important of all, multivariate analyses and RDA analysis indicated that the structure of the macrobenthic community was closely linked to environment factors, including that organic content factor caused the distribution of macrobenthic community mostly during WSDR, while water depth after WSDR affected the macro benthos community structure seriously, and during WSDR, the environment factor influencing it was not single, including organic content, sulfide content, Hg and As. These differences may have been due to changes in water transparency negatively impacting the growth and development of macrobenthos, due to specific lifehistory requirements. Our results demonstrate that anthropogenic activity is having both long-term(3 decadal)and short term(1-month) impacts on the structure of the macrobenthic community of the Huanghe Estuary. In conclusion, human activities WSDR influence the habitat environment of macro benthos, including the water temperature, nutrients, bioturbation, and so on. Therefore, we suggest the necessity to strengthen regulations of land-derived organic pollutant input to maintain the ecological balance of the Huanghe Estuary. 展开更多
关键词 macrobenthos Huanghe(Yellow River) Estuary ecology community structure environment factors
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STUDIES ON THE ENVIRONMENT STRUCTURE OF NATURAL NIDI AND EPIDEMIC AREAS OF HEMORRHAGIC FEVER WITH RENAL SYNDROME IN CHINA 被引量:2
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作者 陈化新 丘福禧 《Chinese Medical Journal》 SCIE CAS CSCD 1994年第2期29-34,共6页
The environment structure of natural nidi and epidemic areas of hemorrhagic fever with renal syndrome (HFRS) possesses characteristics of topography, hydrology, climate, soil, vegetation, and animals. The natural nidi... The environment structure of natural nidi and epidemic areas of hemorrhagic fever with renal syndrome (HFRS) possesses characteristics of topography, hydrology, climate, soil, vegetation, and animals. The natural nidi and epidemic areas of HFRS are distributed mainly in plain and hilly regions under 500 meters above the sea level; in plentiful-water zones and transitional zones; in temperate zone and subtropical zone of the eastern monsoon region; in the abundant-aluminum soil region and the sial soil region; in the eastern China damp forest region (agricultural districts and northeast forest districts); in the eastern Asia dampness-prefering animal geographic region. Apodemus agrarius and Rattus norvegicus are the thriving animal population, predominant species or common species as well as the main reservoir hosts and sources of infection in the natural nidi and epidemic areas of HFRS. 展开更多
关键词 STUDIES ON THE environment structure OF NATURAL NIDI AND EPIDEMIC AREAS OF HEMORRHAGIC FEVER WITH RENAL SYNDROME IN CHINA DH
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Speech endpoint detection in low-SNRs environment based on perception spectrogram structure boundary parameter 被引量:8
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作者 WU Di ZHAO Heming +4 位作者 HUANG Chengwei XIAO Zhongzhe ZHANG Xiaojun XU Yishen TAO Zhi 《Chinese Journal of Acoustics》 2014年第4期428-440,共13页
The Perception Spectrogram Structure Boundary(PSSB)parameter is proposed for speech endpoint detection as a preprocess of speech or speaker recognition.At first a hearing perception speech enhancement is carried out... The Perception Spectrogram Structure Boundary(PSSB)parameter is proposed for speech endpoint detection as a preprocess of speech or speaker recognition.At first a hearing perception speech enhancement is carried out.Then the two-dimensional enhancement is performed upon the sound spectrogram according to the difference between the determinacy distribution characteristic of speech and the random distribution characteristic of noise.Finally a decision for endpoint was made by the PSSB parameter.Experimental results show that,in a low SNR environment from-10 dB to 10 dB,the algorithm proposed in this paper may achieve higher accuracy than the extant endpoint detection algorithms.The detection accuracy of 75.2%can be reached even in the extremely low SNR at-10 dB.Therefore it is suitable for speech endpoint detection in low-SNRs environment. 展开更多
关键词 Speech endpoint detection in low-SNRs environment based on perception spectrogram structure boundary parameter
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TOWARDS SPATIAL LINKAGE PATTERNS OF INDUSTRIAL ORGANIZATIONS IN CHINA
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作者 Fei Hongping(Institute of Macro-Economic Research, State Planning Commission, Beijing 100055People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1995年第4期16-32,共17页
The paper attempts to examine the relationships botween industrial organizations and their environments from an essentially spatial perspective and organizational theory, and inteqrate the generalizations derived from... The paper attempts to examine the relationships botween industrial organizations and their environments from an essentially spatial perspective and organizational theory, and inteqrate the generalizations derived from organizational theory and industrial geography o identify spatial linkage pattems created by the enterprises, both in the aggregate and individually These issues are organized around three elements. From the many organizational and environmental factors which might influence the spatial linkage patterns, six have been selected for analysis. These factors were highly correlated with value or volume of spatial linkages. Changes of spatial linkage pattems over time were analyzed based on a representative sample of the Nanjing Automotive Industrial Corporation, and findings with case studies were illustrated. 展开更多
关键词 enterprise organization spatial linkages organizational structure external environment
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Structured Development Environment Based on the Object-Oriented Concepts
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作者 费翔林 廖雷 +1 位作者 王和珍 汪承藻 《Journal of Computer Science & Technology》 SCIE EI CSCD 1992年第3期193-201,共9页
The object oriented software development is a kind of promising software methodology and leading to a wholly new way for solving problems. In the research on the rapid construction of Structured Development Envi- ronm... The object oriented software development is a kind of promising software methodology and leading to a wholly new way for solving problems. In the research on the rapid construction of Structured Development Envi- ronment (SDE)that supports detailed design and coding in software development, a generator that can gener- ate the SDE has been applied as a metatool. The kernel of SDE is a syntax-directed editor based on the ob- ject-oriented concepts. The key issue in the design of SDE is how to represent the elements of target language with the class concept and a program internally. In this paper, the key concepts and design of the SDE and its generator as well as the implementation of a prototype are to be discussed. 展开更多
关键词 structured Development environment Based on the Object-Oriented Concepts SDE
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A brief review on 7 papers from the special issue of “The environmental significance of soft-sediment deformation” of the Sedimentary Geology 344(2016) 被引量:3
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作者 Zeng-Zhao Feng 《Journal of Palaeogeography》 SCIE CSCD 2017年第4期243-250,共8页
From the viewpoint of origins of soft-sediment deformation structures(SSDS), 7 papers(Ito et al.,2016; Jiang et al., 2016; Lunina and Gladkov, 2016; Moretti et al., 2016; Rana et al., 2016; Rodríguez-Pascua et... From the viewpoint of origins of soft-sediment deformation structures(SSDS), 7 papers(Ito et al.,2016; Jiang et al., 2016; Lunina and Gladkov, 2016; Moretti et al., 2016; Rana et al., 2016; Rodríguez-Pascua et al., 2016; Wheatley et al., 2016) selected from the special issue of "The environmental significance of softsediment deformation" of the Sedimentary Geology 344(2016) were reviewed.(1) The first paper(according to the published order) by Moretti et al. is a general review and introduction of this special issue. This special issue has made an important contribution to the study of sedimentary environments.(2) The fourth paper by Rodríguez-Pascua et al. is an excellent case study. All evidence of earthquake in this paper is reliable. The old Roman City(adjacent to Madrid, the capital of Spain) was definitely destroyed by an earthquake. This paper solved the problem that the archaeologists have not solved yet.(3) The 19 thpaper by Rana et al. is another excellent case study. It demonstrated that SSDS in the youngest modern sediments in the seismically active area, i.e., the Alaknanda Valley, Garhwal Himalaya, India, are of non-seismic origin, but with typically sedimentary origin. All evidence of sedimentary origin of SSDS in the study area is reliable.(4) The second paper by Lunina and Gladkov stated that SSDS(mainly clastic dikes) in epicentral areas of the recent earthquakes in southern Siberia were originated by earthquakes and that the clastic dikes are the most reliable indicators in the epicentral areas of earthquakes. This conclusion is right. However, it is not accurate to consider all clastic injections as "in-situ earthquake structures" in anywhere, because the clastic injections are with multiple origins.(5) The third paper by Wheatley et al. comprehensively stated the clastic pipes of the Jurassic in the Colorado Plateau, USA. However, the principal origin of the clastic pipes(columns) was possibly not originated by "palaeoseismic controls", but by "tectonic controls" or "tectonic uplifts".(6) The 10^(th) paper by Jiang et al.proposed that 6 types of SSDS of the Lixian Section in eastern Tibetan Plateau, i.e., in a tectonically and seismically active area, were originated by earthquakes. However, the evidence of seismic origin is not sufficient. Therefore, the origins of SSDS in the Lixian Section are worthy to be further discussed.(7) The"injectites" and "extrudites" in a Late Pliocene basin on the Boso Peninsula, Japan, from the 24^(th) paper by Ito et al., are non-SSDS and their origin is unreliable.The above viewpoints may be inappropriate. Criticisms and corrections are welcome.This paper is not only the author's brief review on 7 papers selected from the special issue of the Sedimentary Geology 344(2016), but also an invitation to geologists worldwide to write papers for a new special issue of "The origins of SSDS" of the Journal of Palaeogeography which is planned to be published in 2018. 展开更多
关键词 Soft-sediment deformation structures(SSDS) Sedimentary environments Origins Contradictions Review Invitation
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Factors influencing polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran (PCDD/F) emissions and control in major industrial sectors: Case evidence from Shandong Province, China 被引量:2
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作者 Lin Wang Yonglong Lu +4 位作者 Guizhen He Arthur P.J.Mol Tieyu Wang Jorrit Gosens Kun Ni 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第7期1513-1522,共10页
Analyzing determinants that influence polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran(PCDD/F) emissions is helpful for decision-makers to find effective and efficient ways to mitigate PCDD/F emissi... Analyzing determinants that influence polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran(PCDD/F) emissions is helpful for decision-makers to find effective and efficient ways to mitigate PCDD/F emissions. The PCDD/F emissions and the contributions of the scale effect, structure effect and technology effect to emissions from eight main industrial sectors in2006, 2008 and 2010 in Shandong Province, were calculated in this article. Total PCDD/F emissions in Shandong increased by 52.8% in 2008(614.1 g I-TEQ) and 49.7% in 2010(601.8 g I-TEQ) based on 2006(401.9 g I-TEQ). According to the decomposition method, the largest influencing factor on PCDD/F emission changes was the composition effect(contributed 43.4%in 2008 and 120.6% in 2010 based on 2006), which was also an emission-increasing factor.In this case, the present industrial restructuring policy should be adjusted to control the proportion of production capacities with high emission factors, such as iron ore sintering and steelmaking and the secondary non-ferrous metal sector. The scale effect increased the emissions in 2008(contributed 21.9%) and decreased the emissions in 2010(contributed-28.0%). However, as a source control measure, the excess capacity control policy indeed had a significant role in emission reduction. The main reason for the technology effect(contributed 34.7% in 2008 and 7.4% in 2010 based on 2006) having an emission-increasing role was the weakness in implementing policies for restricting industries with outdated facilities. Some specific suggestions were proposed on PCDD/F reduction for local administrators at the end. 展开更多
关键词 JPCDD/F emissions Decomposition analysis Industrial structure environmental policy
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