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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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Study on ecological structures of coastal lakes in Antarctic continent
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作者 王自磐 《Chinese Journal of Polar Science》 2000年第2期147-160,共14页
Coastal region on the Antarctic continent, where it is under the influences both of ocean and ice sheet, as well as frequent human activities, could be considered as a fragile zone in Antarctic ecological environment.... Coastal region on the Antarctic continent, where it is under the influences both of ocean and ice sheet, as well as frequent human activities, could be considered as a fragile zone in Antarctic ecological environment. There are many lakes in coastal region, showing much differences from each other in physical-chemical features because of individual evolutionary history in their geographical environments, and suffering from different outside factors, such as climate changes and precipitation. Thus, it results in respective biological distribution and ecological structure in lakes. The present paper reports the results from the studies of chemical components, species distributions and community structures, which mainly consisted of planktons in lakes in the Vestfold Hills (68°38′S, 78°06′E), and the Larsemann Hills (69°30′S, 76°20′E), East Antarctica. It also treats the biological diversities and nutrient relationships of these different types of lakes. So as to provide more scientific basis for monitoring of climate changes and environmental protection in Antarctica. 展开更多
关键词 ecological structure LAKES Antarctic continent.
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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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Improving Open Spaces for a Sustainable City
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作者 Karin Schwabe Meneguetti Renato Leao Rego 《Journal of Civil Engineering and Architecture》 2013年第9期1150-1156,共7页
The feasibility of city living with nature as a way to restore the balance between human uses and natural processes is the focus of this paper about the city of Maringa in Southern Brazil. This urban form, a planned n... The feasibility of city living with nature as a way to restore the balance between human uses and natural processes is the focus of this paper about the city of Maringa in Southern Brazil. This urban form, a planned new town founded in 1947 upon a previous, comprehensive British land-development scheme, originally offered a friendly interaction between urban settlement and nature. Hence, this paper outlines how open spaces can be enhanced as an ecological structure, bringing parks, squares, gardens and urban farming into a productive system, both for nature's and for people's sakes. Following a morphological study, the proposed ecological structure will maintain ecological processes within the urban grid and help to preserve historical and social values, by linking a wide variety of natural and restored ecosystems and landscape features. The adoption of this kind of ecological planning will certainly result in an increase of the urban landscape quality, changing actual planning paradigm and preventing the city from environmental quality decrease. 展开更多
关键词 Open spaces TOWNSCAPE garden city ecological structure morphological studies.
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Effects of Wetland Utilization Change on Spatial Distribution of Soil Nematodes in Heihe River Basin, Northwest China
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作者 ZHU Hongqiang MAO Zhixia +3 位作者 LONG Zhangwei WANG Yan SU Yongzhong WANG Xuefeng 《Chinese Geographical Science》 SCIE CSCD 2016年第3期339-351,共13页
The first account of the effects of wetland reclamation on soil nematode assemblages were provided, three sites in Heihe River Basin of Northwest China, that is grass wetland(GW), Tamarix chinensis wetland(TW) and cro... The first account of the effects of wetland reclamation on soil nematode assemblages were provided, three sites in Heihe River Basin of Northwest China, that is grass wetland(GW), Tamarix chinensis wetland(TW) and crop wetland(CW) treatments, were compared. Results showed that the majority of soil nematodes were presented in the 0–20 cm soil layers in CW treatments, followed by in the 20–40 cm and 40–60 cm layers in GW treatments. Plant-feeding nametodes were the most abundant trophic groups in each treatment, where GW(91.0%) > TW(88.1%) > CW(53.5%). Generic richness(GR) was lower in the TW(16) than that in GW(23) and CW(25). The combination of enrichment index(EI) and structure index(SI) showed that the soil food web in GW was more structured, and those in TW was stressed, while the enrichment soil food web was presented in the CW treatment. Several ecological indices which reflected soil community structure, diversity, Shannon-Weaver diversity(H′), Evenness(J′), Richness(GR) and modified maturity index(MMI) were found to be effective for assessing the response of soil namatode communities to soil of saline wetland reclamation. Furthermore, saline wetland reclamation also exerted great influence on the soil physical and chemical properties(p H, Electric conductivity(EC), Total organic carbon(TOC), Total nitrogen(Total-N) and Nitrate Nitrogen(N-NO3–)). These results indicated that the wetland reclamation had significantly effects on soil nematode community structure and soil properties in this study. 展开更多
关键词 soil nematode spatial distribution community structure ecological index wetland exploration
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Parameter Ecology for Feedback Vertex Set
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作者 Bart M.P.Jansen Venkatesh Raman Martin Vatshelle 《Tsinghua Science and Technology》 SCIE EI CAS 2014年第4期387-409,共23页
This paper deals with the FEEDBACK VERTEX SET problem on undirected graphs, which asks for the existence of a vertex set of bounded size that intersects all cycles. Due it is theoretical and practical importance,the p... This paper deals with the FEEDBACK VERTEX SET problem on undirected graphs, which asks for the existence of a vertex set of bounded size that intersects all cycles. Due it is theoretical and practical importance,the problem has been the subject of intensive study. Motivated by the parameter ecology program we attempt to classify the parameterized and kernelization complexity of FEEDBACK VERTEX SET for a wide range of parameters.We survey known results and present several new complexity classifications. For example, we prove that FEEDBACK VERTEX SET is fixed-parameter tractable parameterized by the vertex-deletion distance to a chordal graph. We also prove that the problem admits a polynomial kernel when parameterized by the vertex-deletion distance to a pseudo forest, a graph in which every connected component has at most one cycle. In contrast, we prove that a slightly smaller parameterization does not allow for a polynomial kernel unless NP coNP=poly and the polynomial-time hierarchy collapses. 展开更多
关键词 feedback vertex set parameterized complexity parameter ecology program structural parameterizations kernelization
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A Study on the Cloud Design Resource System Based on Ecology Theory
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作者 HUANG Ke-xin 《International Journal of Plant Engineering and Management》 2013年第4期238-242,共5页
The cloud design resource system is an organic entity from the ecological system perspective, whose elements have the similar behavioral property of creature individuals, populations, and community. Hence, study on cl... The cloud design resource system is an organic entity from the ecological system perspective, whose elements have the similar behavioral property of creature individuals, populations, and community. Hence, study on cloud design resource management can refer to the ecology theory. Based on analyzing the structure of cloud design resource system and the features of cloud design resources, the similarity between those are further dis cussed through the ecological system elements and features. An ecological based application framework of cloud design resource management is then presented. 展开更多
关键词 cloud design resource system ecological system elements ecological system structure and property SIMILARITY
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Co-developing an international TLS network for the 3D ecological understanding of global trees:System architecture,remote sensing models,and functional prospects
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作者 Yi Lin Sagi Filin +1 位作者 Roland Billen Nobuya Mizoue 《Environmental Science and Ecotechnology》 SCIE 2023年第4期38-51,共14页
Trees are spread worldwide,as the watchmen that experience the intricate ecological effects caused by various environmental factors.In order to better understand such effects,it is preferential to achieve finely and f... Trees are spread worldwide,as the watchmen that experience the intricate ecological effects caused by various environmental factors.In order to better understand such effects,it is preferential to achieve finely and fully mapped global trees and their environments.For this task,aerial and satellite-based remote sensing(RS)methods have been developed.However,a critical branch regarding the apparent forms of trees has significantly fallen behind due to the technical deficiency found within their globalscale surveying methods.Now,terrestrial laser scanning(TLS),a state-of-the-art RS technology,is useful for the in situ three-dimensional(3D)mapping of trees and their environments.Thus,we proposed co-developing an international TLS network as a macroscale ecotechnology to increase the 3D ecological understanding of global trees.First,we generated the system architecture and tested the available RS models to deepen its ground stakes.Then,we verified the ecotechnology regarding the identification of its theoretical feasibility,a review of its technical preparations,and a case testification based on a prototype we designed.Next,we conducted its functional prospects by previewing its scientific and technical potentials and its functional extensibility.Finally,we summarized its technical and scientific challenges,which can be used as the cutting points to promote the improvement of this technology in future studies.Overall,with the implication of establishing a novel cornerstone-sense ecotechnology,the co-development of an international TLS network can revolutionize the 3D ecological understanding of global trees and create new fields of research from 3D global tree structural ecology to 3D macroecology. 展开更多
关键词 Global trees Terrestrial laser scanning(TLS) International TLS network Three-dimensional(3D)ecotechnology 3D global tree structural ecology 3D macroecology
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Evolution Characteristics of the Ecological Space Network of Resource-Based Cities:A Case Study on Xuzhou 被引量:2
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作者 Liang Xinbin Ji Xiang +3 位作者 Guo Nana Meng Lingran Qian Fang(Translated) Liang Sisi(Proofread) 《China City Planning Review》 CSCD 2021年第2期62-74,共13页
The territorial and spatial planning is an essential tool for ecological civilization construction in spatial development and urban governance.Since ecological space has been an important part of the territorial and s... The territorial and spatial planning is an essential tool for ecological civilization construction in spatial development and urban governance.Since ecological space has been an important part of the territorial and spatial planning,this study established a spatial structural pattern of"ecological source-ecological corridor-ecological node"along with methods including landscape connectivity analysis and ecological resistance surface analysis.Taking the ecological space of Xuzhou City,a typical resource-based city,as a case study,this research analyzed the ecological spatial network structure and evaluated the evolution characteristics before judging the breadth threshold value of the ecological corridor and providing planning control strategy.The study found that since the urbanization of Xuzhou City resumed its growth,the quantity of ecological sources,corridors,and nodes have grown along.The resistance of the ecological corridor increases year by year,with the proper breadth threshold value around 100–200 m.The development of an ecological network structure shows a single-polarization evolution characteristic that is high quality and high resistance. 展开更多
关键词 ecological space landscape connectivity ecological resistance surface ecological space network structure ecological corridor Xuzhou City
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