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The Research on Land-Use Change and Ecological Environment Effect of Urban Landscape in China 被引量:2
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作者 Dengfei Li Youyou Huang +2 位作者 Bo Qiao Xianchun Yan Wei He 《International Journal of Geosciences》 2016年第7期956-961,共6页
The rapid expansion of urban construction land has become the major characteristic of urban land-use change in China today. Meanwhile, the rapid urbanization process has led to the great changes of urban landscape in ... The rapid expansion of urban construction land has become the major characteristic of urban land-use change in China today. Meanwhile, the rapid urbanization process has led to the great changes of urban landscape in China, and it also has had certain impacts on environmental factors such as climate, soil, hydrology, biodiversity, etc., then it has made the overall ecological environment deteriorated. This study is based on the summary and analysis of research on land-use change and ecological environment effect of urban landscape in recent 20 years in China, and it aims at providing scientific bases and theoretical supports for the planning and construction of urban landscape, the sustainable land-use of city and the protection of ecological environment in China. 展开更多
关键词 Urban Landscape Ecological environment effect URBANIZATION LUCC
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Maternal Environment Effects on Phenolic Defenses in <i>Abutilon theophrasti</i>Seeds
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作者 Brian J. Schutte Sam E. Wortman +1 位作者 John L. Lindquist Adam S. Davis 《American Journal of Plant Sciences》 2013年第5期1127-1133,共7页
A class of phenolic compounds, ortho-dihydroxyphenols (hereafter “o-DHP”), has been implicated with seed survival. Based on expectations of the growth-differentiation balance hypothesis, we predicted that seed o-DHP... A class of phenolic compounds, ortho-dihydroxyphenols (hereafter “o-DHP”), has been implicated with seed survival. Based on expectations of the growth-differentiation balance hypothesis, we predicted that seed o-DHP concentration exhibits a curvilinear response to increasing resource availability in the maternal environment, with maximum o-DHP occurring at moderate resource levels. To test this hypothesis, Abutilon theophrasti seeds were produced under field conditions at two locations. Each location included twelve maternal environments established through factorial combinations of soil compost (+/-), species assemblage (A. theophrasti with and without maize), and soil nitrogen fertilizer (0, 0.5× or 1× local recommendations for maize). Resource availability with respect to A. theophrasti growth was summarized by above-ground biomass at seed harvest (maternal biomass). Results indicated that seed o-DHP concentrations increased then decreased in response to increasing maternal biomass. This relationship was modeled with a unimodal function specific to location (Location 1, y = 1.18 + 0.03xe-0.02x, pseudo-R2 = 0.59, p = 0.003;Location 2, y = 1.40 + 0.006xe-0.005x;pseudo-R2 = 0.34, p = 0.05). Seed protein concentrations remained constant across maternal biomass levels. Because inherent vulnerability to predation and decay is considered a consequence of chemical protection relative to nutritional offering, our results suggest that A. theophrasti seed susceptibility to lethal attack is influenced by resource levels in the maternal environment. More broadly, our results suggest that the growth-differentiation balance hypothesis can be extended to maternal effects on seed phenolics. 展开更多
关键词 environmental Maternal effect Growth-Differentiation Balance Hypothesis ortho-Dihydroxyphenols SEED Defense SEED Protein
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Opportunities to Improve the Quality of Environmental Reports and the Effectiveness of Environmental Impact Assessment: A Case of Electric Power Transmission Systems in Brazil
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作者 Vinícius Arthico Demori Marcelo Montaño 《Journal of Environmental Protection》 2024年第2期124-140,共17页
A good quality Environmental Impact Statement (EIS) is key for the effectiveness of Environmental Impact Assessment (EIA) processes and consequently to the acceptability of projects subject to EIA. The international l... A good quality Environmental Impact Statement (EIS) is key for the effectiveness of Environmental Impact Assessment (EIA) processes and consequently to the acceptability of projects subject to EIA. The international literature has contributed to the understanding of the essential aspects to be verified regarding the quality of EIS, offering a wide spectrum of good practice examples related to the content of the studies. Even so, there is a need for empirical studies that allow the identification of specific aspects related to the context of application of the EIS, which could lead to the identification of opportunities to improve both the quality of the reports and also the effectiveness of EIA. Therefore, the present paper is focused on the quality review of a number of EIS submitted to the Brazilian Federal Environmental Agency (Ibama) to instruct the assessment of electric power transmission systems. Based on the application of the EIS quality review package as proposed by Lee and Colley (1992), the outcomes reveal opportunities for improving the scope of EIA, analysis of alternatives, prediction of magnitude and the assessment of impact significance. Finally, the development and/or adaptation of a similar tool for the systematic review of the quality of EIA reports is recommended. 展开更多
关键词 environmental Impact Assessment effectIVENESS Electric Energy Transmission Systems
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Hospital Stakeholders’ Perception on Environmental Effects Related to Biomedical Waste in Togo’s University Hospitals (UHC) in 2021
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作者 Takpaya Gnaro Awedeou Ali +6 位作者 Kokou Ayamekpe Cyriaque Degbey Farouk Salami-Odjo Abdoul-Rahim Ouro-Koura Panaveyi Malou Adom Ghislain Emmanuel Sopoh Didier Koumavi Ekouevi 《Open Journal of Preventive Medicine》 CAS 2023年第2期57-72,共16页
Introduction: Given its effects, hospital waste is an environmental concern and a threat to health personnel, users of health services and neighboring populations. Our objective was to assess the perception of health ... Introduction: Given its effects, hospital waste is an environmental concern and a threat to health personnel, users of health services and neighboring populations. Our objective was to assess the perception of health care stakeholders on the environmental effects related to biomedical waste produced in Teaching Hospitals (CHU) in Togo in 2021. Methods: This was a cross-sectional study held from June 24 to August 28, 2021. It targeted three university hospitals, 340 health care providers and services selected by a probabilistic method with a simple random technique in 25 services, 72 directors, deputy directors, supervisors and heads of services, 27 collection and incineration agents selected by a non-probabilistic method with a reasoned choice technique, 44 patients and attendants and 36 householders of neighboring residents selected by a non-probabilistic method with an accidental choice technique. Variables such as the spreading of disease vectors, soil, air and water contamination, the presence of unpleasant odors and unsightly living conditions were assessed. Results: According to the respondents, biomedical waste causes the proliferation of vectors (55.3%), an unsightly environment inside the hospital (47.1%), and unpleasant odors (61.2%). Incineration operations disturb hospital residents (52.8%), according to the householders of the residents. During observation, we note deposits of waste that have not been destroyed and wastewater flowing in some places. Conclusion: Biomedical waste in Togo’s university hospitals generates environmental effects and therefore potentially high risks for human health. Improving their management should be a concern for all hospital actors. 展开更多
关键词 environmental effects Biomedical Waste Teaching Hospitals environment TOGO
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Environmental and Health Effects Associated With Harmful Algal Bloom and Marine Algal Toxins in China 被引量:6
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作者 TIANYAN1 MING-JIANGZHOU 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2004年第2期165-176,共12页
The frequency and scale of Harmful Algal Bloom (HAB) and marine algal toxin incidents have been increasing and spreading in the past two decades, causing damages to the marine environment and threatening human life th... The frequency and scale of Harmful Algal Bloom (HAB) and marine algal toxin incidents have been increasing and spreading in the past two decades, causing damages to the marine environment and threatening human life through contaminated seafood. To better understand the effect of HAB and marine algal toxins on marine environment and human health in China, this paper overviews HAB occurrence and marine algal toxin incidents, as well as their environmental and health effects in this country. HAB has been increasing rapidly along the Chinese coast since the 1970s, and at least 512 documented HAB events have occurred from 1952 to 2002 in the Chinese mainland. It has been found that PSP and DSP toxins are distributed widely along both the northern and southern Chinese coasts. The HAB and marine algal toxin events during the 1990s in China were summarized, showing that the HAB and algal toxins resulted in great damages to local fisheries, marine culture, quality of marine environment, and human health. Therefore, to protect the coastal environment and human health, attention to HAB and marine algal toxins is urgently needed from the environmental and epidemiologicalview. 展开更多
关键词 HAB Algal toxins environment effect Health effect
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QTL Mapping for Wheat Flour Color with Additive,Epistatic,and QTL×Environmental Interaction Effects 被引量:3
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作者 LI Wei-hua LIU Wei +3 位作者 LIU Li YOU Min-shan LIU Guang-tian LI Bao-yun 《Agricultural Sciences in China》 CAS CSCD 2011年第5期651-660,共10页
To investigate genetic factors affecting wheat flour color traits,a linkage map was constructed using a recombinant inbred line (RIL) population derived from Jing 771×Pm 97034.Main,epistatic and QTL×enviro... To investigate genetic factors affecting wheat flour color traits,a linkage map was constructed using a recombinant inbred line (RIL) population derived from Jing 771×Pm 97034.Main,epistatic and QTL×environment (QE) interaction effects of quantitative trait loci (QTLs) controlling wheat flour color were studied by the mixed linear modeling of data collected from wheat RIL plants under three different environmental conditions.13 QTLs with additive effects and 55 pairs of QTLs with epistatic effects were detected for wheat flour color traits.The additive-additive interactions (AA) involved all of the wheat chromosomes except 3D.Epistasis accounted for more of the observed phenotypic variation than did the main effect QTLs (M-QTLs).Our results suggested that dual-locus interactions are widespread in the wheat genome and play a critical role in determining wheat flour color characteristics.In this study,3 QTLs were identified to have QE interaction effects,one of them showing significant QE interaction in E2 environment. 展开更多
关键词 epistatic effects flour color QTL×environment effects quantitative trait loci Triticum aestivum
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Environmental Impact Assessment Follow-Up of Seismic Survey Offshore Activities in Brazil
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作者 Fontes Nuno Eduardo Paulo Marcelo Montaño 《Journal of Environmental Protection》 2024年第2期141-155,共15页
Follow-up of environmental impacts is an integral part of the Environmental Impact Assessment (EIA) process, closely related to the effectiveness of the instrument. EIA follow-up has been receiving a lot of interest f... Follow-up of environmental impacts is an integral part of the Environmental Impact Assessment (EIA) process, closely related to the effectiveness of the instrument. EIA follow-up has been receiving a lot of interest from scientists and practitioners, though it is recognized as one of the weakest points of EIA systems globally. Also, EIA follow-up is influenced by the context, mainly in terms of the types of projects or activities and their related impacts on the environment. Therefore, the present paper is focused on the investigation of the follow-up stage applied to the activity of seismic survey coupled with offshore oil & gas exploitation in Brazil. Research was based on a qualitative approach that included document analysis and semi-structured interviews with analysts involved in EIA processes, and sought to generate evidence of effectiveness of the EIA follow-up as conducted by the Federal Environment Agency (Ibama) in order to situate the practice of follow-up in the broader context of international best practice principles. Based on the findings, it was concluded that, due to the peculiarities of offshore seismic survey, it is necessary to promote adaptations in the procedures for monitoring impacts in order to ensure proper alignment with the principles and conceptual foundations that guide EIA practice. Specifically, the timing of the execution of the activity imposes challenges for its integration into the “conventional” cycle that has guided the monitoring of the impacts in the EIA of projects. 展开更多
关键词 environmental Impact Assessment Follow-Up Follow-Up effectiveness Oil and Gas Offshore Seismic Survey
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Weathering-pedogenesis of Carbonate Rocks and Its Environmental Effects in Subtropical Region 被引量:4
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作者 ZHU Lijun HE Shouyang LI Jingyang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第5期982-993,共12页
We investigated the weathering-pedogenesis of carbonate rocks and its environmental effects in subtropical regions of China. The investigation demonstrated that the weathering- pedogenesis of carbonate rocks is the pr... We investigated the weathering-pedogenesis of carbonate rocks and its environmental effects in subtropical regions of China. The investigation demonstrated that the weathering- pedogenesis of carbonate rocks is the process of a joint action of corrosion and illuviation and metasomatism in subtropical region. It is characterized by multi-stage, multi-path and multi-style. With the persisting development of weathering-pedogenesis of carbonate rocks, metasomatic pedogenesis progressively became the main process of the weathering-pedogenesis and the dominant style of formation of minerals. And it proceeds through the whole process of evolution of the weathering-pedogenesis of carbonate rocks. The stage evolution of weathering-pedogenesis of carbonate rocks and the fractionation evolution of newly produced minerals are characterized by obvious vertically zoning structures and the rules of gradation of elements geochemical characteristics in the carbonate rocks weathering profiles. The geochemical process of weathering-pedogenesis of carbonate rocks can be divided into three geochemical evolution stages, i.e., the Ca, Mg-depletion and Si, Al-enrichment stage; the Fe, Mn enrichment stage and the Si-depletion and Al-enrichment stage in the subtropical regions. Consistent with the three geochemical evolution stages, the sequence of formation and evolution of minerals can be divided into the clay mineral stage; the Fe, Mn oxide and the gibbsite stage. The influence of weathering-pedogenesis of carbonate rocks on the chemical forms of heavy elements is mainly affected via newly produced components and minerals in the process of weathering-pedogenesis, e.g., iron oxide minerals and organic matters. The important mechanism for the mobilization, transport and pollution of F and As is affected the selective adsorption and desorption of F and As on the surface of iron oxide minerals in the subtropical karst zones, i.e., the selective adsorption and desorption on mineral surfaces of newly produced minerals in the process of weathering-pedogenesis control the geochemical behavior of elements on the Earth's surface and environmental quality in subtropical regions. 展开更多
关键词 carbonate rocks weathering-pedogenesis metasomatic pedogenesis environmental effects subtropical region
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The impact of cropland conversion on environmental effect in the Loess Plateau: a pilot study based on the national experimental bases 被引量:3
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作者 WANG Fei LI Rui +2 位作者 JIAO Feng YANG Qingke TIAN Junliang 《Journal of Geographical Sciences》 SCIE CSCD 2005年第4期484-490,共7页
Conversion of cropland to forestry and grassland is an important method to reduce soil erosion and improve the biophysical environment in the Loess Plateau. The feasibility, methods, and environmental effects of cropl... Conversion of cropland to forestry and grassland is an important method to reduce soil erosion and improve the biophysical environment in the Loess Plateau. The feasibility, methods, and environmental effects of cropland conversion were studied based on 11 typical watersheds of national experimental bases instead of different geographic areas of the Loess Plateau. Between 1986 and 2000, cropland, sloping cropland and non-agricultural land decreased by 8%, 92.5% and 8% respectively, while forestry increased by 15.7%. The land use change not only decreased annual soil erosion by 74%, but also increased vegetation coverage by 100% and improved the soil condition and biodiversity. This can be achieved by building basic farmland, increasing capital and scientific input, and planting trees and grasses according to the natural biophysical restrictions. 展开更多
关键词 Loess Plateau land use and cover change cropland conversion environmental effect
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Variations of nutrient elements and its effect on ecological environment off the Changjiang estuarine waters 被引量:2
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作者 Lin Yi’ an, Tang Renyou, Pan Jianming, Jin Mingming ( Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2001年第2期197-208,共11页
On the basis of the date obtained in two cruises during October 1997 and May 1998, the concentration distribution and the variation of present species of nutrient elements in the water masses are described. The trans... On the basis of the date obtained in two cruises during October 1997 and May 1998, the concentration distribution and the variation of present species of nutrient elements in the water masses are described. The transform mechanism of present species of nutrients and the of differrnt water masses, frontal area and thermohaline transition layer on convergence or divergence and the biogeochemical cycle of nutrient elements off the Changjiang Estuary are studied. Meanwhile, the environmental capaci- ty of nutrients is primarily estimated: they are 1.803 x 104t DIN and 6.18 x 102t PO43- -P in autumn, and 4.20x 102t PO43- -P in spring. 展开更多
关键词 Nutrient element biogeochemical cycle ecological environmental effect the Changjiang Estuary
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Dynamic Variation Characteristics of Phosphorus in Paddy Field Runoff in Saline Land and Its Potential Environmental Effect 被引量:2
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作者 YUAN Rui-xia, YE Jie-qiong, WANG Zhao-hui, LIU Jian-she College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China 《Meteorological and Environmental Research》 CAS 2011年第4期72-75,78,共5页
[Objective] The aim was to study the dynamic variation characteristics of phosphorus in paddy field runoff in saline land and its potential environmental effect. [Method] Taking Qianguo irrigation district in soda-sal... [Objective] The aim was to study the dynamic variation characteristics of phosphorus in paddy field runoff in saline land and its potential environmental effect. [Method] Taking Qianguo irrigation district in soda-saline land in Songnen Plain as study object, the dynamic variation law of phosphorus in paddy field runoff under different irrigation conditions and its potential environmental effect were discussed. [Result] Surface water in paddy field was alkaline, and scattered soil had poor fertilizer conservation capacity. Phosphorus accumulated in soil surface, which could increase the risk of phosphorus loss. Phosphorus loss in paddy field mainly occurred in irrigation period and runoff period caused by rainstorm. The concentration of total phosphorus (TP), particulate phosphorus (PP), total dissolved phosphorus (TDP) and dissolved reactive phosphorus (DRP) in paddy field runoff decreased with time, especially PP. Phosphorus concentration exceeded critical value and resulted to eutrophication, which threatened the water quality security of Chagan Lake. Phosphorus concentration in water recession canal increased with time, and eutrophication with different degrees appeared under high temperature. TP concentration in surface water of paddy field was highly negatively correlated with that in water recession canal, and the correlation coefficients R2(α=0.05)in three paddy fields were 0.850 9, 0.896 4 and 0.915 3, respectively. The pollution load of phosphorus in paddy field with the best irrigation condition was higher, and its pollution risk was the highest. Thus, such fields should be monitored and controlled mainly as the critical source area of phosphorus loss. [Conclusion] The study could provide theoretical foundations for developing saline land rationally, establishing optimal management measure of phosphorus in saline land and controlling phosphorus loss from farmland to protect local water resources. 展开更多
关键词 Saline soil PHOSPHORUS Dynamic variation characteristics Potential environmental effect China
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Research progress on behaviors and environmental effects of mercury in the cryosphere of the Tibetan Plateau:a critical review 被引量:1
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作者 ShiWei Sun ShiChang Kang +2 位作者 QiangGong Zhang JunMing Guo XueJun Sun 《Research in Cold and Arid Regions》 CSCD 2022年第1期1-22,共22页
The behavior and fates of environmental pollutants within the cryosphere and the associated environmental impacts are of increasing concerns in the context of global warming.The Tibetan Plateau(TP),also known as the&q... The behavior and fates of environmental pollutants within the cryosphere and the associated environmental impacts are of increasing concerns in the context of global warming.The Tibetan Plateau(TP),also known as the"Third Pole",represents one of the most important cryospheric regions in the world.Mercury(Hg)is recognized as a global pollutant.Here,we summarize the current knowledge of Hg concentration levels,pools and spatio-temporal distribution in cryospheric environments(e.g.,glacier,permafrost),and its transfer and potential cycle in the TP cryospheric region.Transboundary transport of anthropogenic Hg from the surrounding heavily-polluted regions,such as South and Southeast Asia,provides significant sources of atmospheric Hg depositions onto the TP cryosphere.We concluded that the melting of the cryosphere on the TP represents an increasing source of Hg and brings a risk to the TP environment.In addition,global warming acts as an important catalyst accelerating the release of legacy Hg from the melting cryosphere,adversely impacting ecosystems and biological health.Furthermore,we emphasize on the remaining gaps and proposed issues needed to be addressed in future work,including enhancing our knowledge on some key release pathways and the related environmental effects of Hg in the cryospheric region,integrated observation and consideration of Hg distribution,migration and cycle processes at a key region,and uses of Hg isotopic technical and Hg models to improve the understanding of Hg cycling in the TP cryospheric region. 展开更多
关键词 MERCURY CRYOSPHERE environmental effects Tibetan Plateau
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RELATIVE SEA LEVEL RISE AND ITS EFFECTS ON ENVIRONMENT AND RESOURCES IN CHINAS COASTAL AREAS 被引量:2
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作者 杨桂山 《Chinese Geographical Science》 SCIE CSCD 1995年第2期104-115,共12页
Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21... Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21st century. It will result in a series of adverse impacts on evolution of natural environment and socioeconomic development of the coastal area. This paper analyses environmental and resource effects induced by relative sea level rise in China's coastal areas on the basis of rough estimate of future relative sea level rise. These effects include inundating tidal flat and wetlands and increase in inundated risk of coastal habitable land,exacerbating storm surge. coastal erosion, flooding and salt water intrusion hazards.as well as endangering land. water. tourism and living resources and their utilization. 展开更多
关键词 China’s COASTAL areas. RELATIVE SEA LEVEL RISE environmental effect resource effect
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Land Use Change During 1960~2000 Period and itsEco-environmental Effects in the Middle and UpperReaches of the Yangtze River:a Case Study in YiliangCounty,Yunnan,China 被引量:4
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作者 YANGZisheng LIANGLuohui +1 位作者 LIUYansui HEYimei 《Journal of Mountain Science》 SCIE CSCD 2004年第3期250-263,共14页
Land use/land cover change (LUCC) is a focus of the research of global environmental changes. The middle and upper reaches of the Yangtze River, which are the most ecologically fragile mountainous area in China as wel... Land use/land cover change (LUCC) is a focus of the research of global environmental changes. The middle and upper reaches of the Yangtze River, which are the most ecologically fragile mountainous area in China as well as one of the areas in China with most notable LUCC, have been on the Chinese Government's list of priority areas for ecological restoration. This paper is to reveal the trend of LUCC and the ecological degradation arising from it, and to provide a basis for the future sustainable use of land resources in the region based on a detailed analysis of Yiliang County. Based on the county's land use/cover maps in 1960, 1980 and 2000 drawn with the aid of aerial photograph interpretation, field investigation and GIS based spatial-temporal data analysis, LUCC during 1960~2000 period and the ecological degradation arising from it were analyzed. Using the Markv model, the paper brings out a forecast of what the county's LUCC would be like if the county's current land use continues, as well as the reasons and countermeasures for restoring degraded ecosystems. 展开更多
关键词 LUCC 驱动力 经济环境效益 生态安全 扬子江 上游河段
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Environmental effects induced by excavation 被引量:1
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作者 Yu-qi LI Jian ZHOU Kang-he XIE 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第1期50-57,共8页
Based on 3D Biot’s consolidation theory and nonlinear Duncan-Chang’s model, a 3D FEM (finite element method) program is developed considering the coupling of groundwater seepage and soil skeleton deformation during ... Based on 3D Biot’s consolidation theory and nonlinear Duncan-Chang’s model, a 3D FEM (finite element method) program is developed considering the coupling of groundwater seepage and soil skeleton deformation during excavation. The comparison between the analysis result considering the variation of water head difference and that without considering it shows that the porewater pressure distribution of the former is distinctly different from that of the latter and that the foundation pit de- formations of the former are larger than those of the latter, so that the result without considering the variation of water head dif- ference is unreliable. The distribution rules of soil horizontal and vertical displacements around the pit and excess porewater pressure are analyzed in detail in time and space, which is very significant for guiding underground engineering construction and ensuring environment safety around the pit. 展开更多
关键词 环境作用 地基变形 孔隙压力 建筑工程
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Geochemistry and environmental effect of cadmium in the super-large Jinding Pb-Zn deposit,Yunnan Province, China 被引量:1
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作者 LI Hang LI Dahua +5 位作者 XIAO Tangfu HE Libin NING Zengping SUN Jialong ZHU Changsheng SHUANG Yan 《Chinese Journal Of Geochemistry》 EI CAS 2008年第1期21-27,共7页
The Jinding Pb-Zn deposit in Yunnan Province is the representative of a Cd-enriched area and mining activities lead to the release of Cd into the hypergenic ecosystem, resulting in Cd pollution. The concentrations of ... The Jinding Pb-Zn deposit in Yunnan Province is the representative of a Cd-enriched area and mining activities lead to the release of Cd into the hypergenic ecosystem, resulting in Cd pollution. The concentrations of Cd vary greatly from one type to another type of rocks in the mining district. In the host rock, Cd concentrations range from 50×10-6 to 650×10-6 with an average of 310×10-6. In primary ores, Cd concentrations range from 14×10-6 to 2800×10-6 with an average of 767×10-6. However, in oxidized ores, Cd concentrations are highest, varying within the range of 110×10-6 to 8200×10-6 , averaging 1661×10-6. It is shown that the oxidized ores are the main carrier and environmental source of Cd. Leaching test showed that Pb/Zn ores are easy to oxidize and thereafter release Cd and other harmful elements. These leached elements in the leachate may be precipitated rapidly in the order of Zn>Pb>Cd. As for the concentration distribution of Cd in the Bijiang River, it is estimated to be 15.7 μg/L Cd in water, 49.3 mg/L in suspended substances, and 203.7 mg/L in sediments. The average value of Cd in soil from the polluted area is 83.0 mg/kg. Natural weathering of Cd-rich rocks and minerals imposes a potential environmental risk on the aquatic ecosystem of the Bijiang catchment. 展开更多
关键词 地理特征 环境系统 化合物 测定方法
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The Environmental Effects of Tourism Architecture on Island Ecosystem in Cayo Guillermo, Cuba 被引量:2
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作者 Lourdes Ruiz Gutiérrez 《Journal of Environmental Protection》 2015年第9期1057-1065,共9页
The objective of this study is to determine the main adverse impacts that may be caused by tourism architecture upon island ecosystems consisting of small islands or islets and to propose an architectural and landscap... The objective of this study is to determine the main adverse impacts that may be caused by tourism architecture upon island ecosystems consisting of small islands or islets and to propose an architectural and landscape design with a focus on the environmental sustainability of the same. A study of projects was undertaken in Cayo Guillermo, located to the north of Ciego de Avila in Cuba using methods of life-cycle assessment of buildings, matrix methods of the activities that caused severe environmental impact and statistical processing through multivariate analysis. Conclusions were reached on the need for designs that did not harm the ecosystems of islands with high ecological fragility. It has been determined that suitable construction intervention would decrease the negative impact and would allow the natural resources of these valuable ecosystems that are the basis for responsible sun and sand tourism to be preserved. 展开更多
关键词 environmentAL effects ARCHITECTURE TOURISM ISLAND ECOSYSTEM
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Influence of the environmental behavior and ecological effect of cropland heavy metal contaminants by CO_2 enrichment in atmosphere 被引量:4
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作者 Hongyan GUO Haixia JIA +1 位作者 Jianguo ZHU Xiaorong WANG 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期212-212,共1页
关键词 环境行为 生态效应 重金属 环境污染 大气污染 二氧化碳 FACE
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The Effects of the Enriched Environment on Sympathetic Skin Response in Pentylenetetrazol-Kindled Rats 被引量:2
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作者 Nazan DOLU Seval KELOGLAN +1 位作者 Soner BITIKTAS Setenay CUG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第5期394-397,共4页
Epilepsy is a neurodegenerative disease that interrupts the normal electrical activity of the brain and promotes abnormal wiring in this organ.Epileptic seizures are often associated with significant changes in the fu... Epilepsy is a neurodegenerative disease that interrupts the normal electrical activity of the brain and promotes abnormal wiring in this organ.Epileptic seizures are often associated with significant changes in the functioning of the autonomic nervous system(ANS). 展开更多
关键词 The effects of the Enriched environment on Sympathetic Skin Response in Pentylenetetrazol-Kindled Rats CAGE
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EFFECT OF ENVIRONMENTAL FIELD ON TROPICAL CYCLONE TRACK AFTER LANDFALL FROM EAST CHINA SEA 被引量:1
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作者 钟元 余晖 王东法 《Journal of Tropical Meteorology》 SCIE 2006年第2期201-204,共4页
关键词 环境场 热带气旋 登陆轨迹 统计性学习
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