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Evaluation of the migration and environmental effects of metal elements within cementitious gangue-fly ash backfill in underground coal mines
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作者 Xuejie Deng Yuan Jiao +5 位作者 Shicong Li Nan Zhou Yan An Erol Yilmaz Qingxue Zheng Xifeng Liang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第11期1551-1562,共12页
Cementitious gangue-fly ash backfill(CGB)is used as a green mining technology worldwide.However,under the coupled effects of geological stress and groundwater,the metal elements in the CGB tend to migrate into nearby ... Cementitious gangue-fly ash backfill(CGB)is used as a green mining technology worldwide.However,under the coupled effects of geological stress and groundwater,the metal elements in the CGB tend to migrate into nearby strata,which can consequently result in pollution of the groundwater environment.In this paper,the influence of initial pH and stress damage on the migration behavior of metal elements in CGB is quantitatively studied through the multi-physical field coupling model of stress-permeability-con centration.The enhanced Nemerow index evaluation method is used to comprehensively evaluate the impact of these metal elements migration behaviors on the groundwater environment.The research results show that:(1)When the stress damage of the CGB increases from 0.76 to 0.95,the Darcy velocity at the bottom of the CGB first increases,then decreases,and finally stabilizes at 2.01×10^(-7)m/s.The longest time to reach the maximum Darcy velocity is 3 a.(2)When the damage of the CGB is 0.95,the farthest migration distances of Al,Cr,Mn,Fe,Ba,and Pb are 40.5,34.0,29.8,32.9,38.8 and 32.1 m,respectively.(3)The alkaline environment stimulates the migration of Al,Cr,Fe,Mn,and Pb,whereas Ba migrates farther under acidic conditions.The farthest migration distance of Ba is 31.6 m under pH 3.(4)The enhanced Nemerow index indicates that when stress damage increases from 0.76 to 0.95,the areas with poor water quality increase from 0 to 1.71%,and no area is classified as very poor grade.When the initial pH changes from 3 to 11,100%of the region is classified as fair or above.The initial pH of the CGB has a relatively slight influence on the groundwater environment.This study provides experimental data and theoretical basis for the environmental evaluation of CGB. 展开更多
关键词 Cementitious gangue-fly ash backfill Metal elements Migration patterns environmental effects Geological stress damage pH
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Carbon fluxes and their response to environmental variables in a Dahurian larch forest ecosystem in northeast China 被引量:6
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作者 王辉民 三枝信子 +3 位作者 祖元刚 王文杰 山本晋 近藤裕昭 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第1期1-10,共10页
The Dahurian larch forest in northeast China is important due to its vastness and location within a transitional zone from boreal to temperate and at the southern distribution edge of the vast Siberian larch forest. T... The Dahurian larch forest in northeast China is important due to its vastness and location within a transitional zone from boreal to temperate and at the southern distribution edge of the vast Siberian larch forest. The continuous carbon fluxes were measured from May 2004 to April 2005 in the Dahurian larch forest in Northeast China using an eddy covariance method. The results showed that the ecosystem released carbon in the dormant season from mid-October 2004 to April 2005, while it assimilated CO2 from the atmosphere in the growing season from May to September 2004. The net carbon sequestration reached its peak of 112 g.m^-2.month ^-1 in June 2004 (simplified expression of g (carbon).m^-2.month^-1) and then gradually decreased. Annually, the larch forest was a carbon sink that sequestered carbon of 146 g-m^-2.a^-1 (simplified expression of g (carbon).m^-2.a^-1) during the measurements. The photosynthetic process of the larch forest ecosystem was largely affected by the vapor pressure deficit (VPD) and temperature. Under humid conditions (VPD 〈 1.0 kPa), the gross ecosystem production (GEP) increased with increasing temperature. But the net ecosystem production (NEP) showed almost no change with increasing temperature because the increment of GEP was counterbalanced by that of the ecosystem respiration. Under a dry environment (VPD 〉 1.0 kPa), the GEP decreased with the increasing VPD at a rate of 3.0 μmol.m^-2.s^-1kPa -1 and the ecosystem respiration was also enhanced simultaneously due to the increase of air temperature, which was linearly correlated with the VPD. As a result, the net ecosystem carbon sequestration rapidly decreased with the increasing VPD at a rate of 5.2 μmol.m^-2.s-1.kPa^-1. Under humid conditions (VPD 〈 1.0 kPa), both the GEP and NEP were obviously restricted by the low air temperature but were insensitive to the high temperature because the observed high temperature value comes within the category of the optimum range. 展开更多
关键词 carbon balance eddy covariance method environmental effect larch forest Larix gmelinii
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Effects of Slow Release Fertilizer on the Yield and Nutrient Use Efficiency of Carnation and Its Environmental Protection Effect 被引量:4
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作者 杜彩艳 段宗颜 +1 位作者 胡万里 陈拾华 《Agricultural Science & Technology》 CAS 2011年第4期571-575,共5页
[Objective] The aim was to study the effects of slow release fertilizer on the yield,economic benefit and nutrient use efficiency of carnation and environmental pollution.[Method] Taking carnation(Dianthus caryophyl... [Objective] The aim was to study the effects of slow release fertilizer on the yield,economic benefit and nutrient use efficiency of carnation and environmental pollution.[Method] Taking carnation(Dianthus caryophyllus)as research object,the application effect and environmental protection effect of slow release fertilizer on carnation were discussed through field plot test.[Result] The main agronomic characters of carnation improved after the application of slow release fertilizer;compared with Conv-F treatment,the yield of carnation with slow release fertilizer increased by 18.67%-20.83%,and its economic benefit increased by 105 500 yuan/hm2,while the ratio of output to input improved by 74.29%;under the same NPK ratio and nutrient amount,the yield,economic benefit and ratio of output to input of carnation after the application of slow release fertilizer increased by 2.11%,14 800 yuan and 16.2%,respectively;besides,the application of slow release fertilizer improved the nutrient use efficiency of carnation,and N,P and K nutrient use efficiency in Opt-F-0.7% treatment increased by 13.88%,8.57% and 30.14% compared with Conv-F treatment.[Conclusion] Slow release fertilizer could not only reduce the waste of fertilizer resources and improve fertilizer use efficiency but also decrease the pollution caused by nutrient loss,which had important practical significance for protecting ecological environment and promoting the sustainable development of agriculture. 展开更多
关键词 Slow release fertilizer CARNATION YIELD Nutrient use efficiency environmental protection effect
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Comprehensive Evaluation of Environmental Effects from Land Change in Hotan Oasis,Xinjiang 被引量:5
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作者 杨依天 王乃河 王平 《Agricultural Science & Technology》 CAS 2014年第4期653-658,共6页
[Objective] This study aimed to evaluate the environmental effects coming from land changes in Hotan oasis during 1980-2010. [Method] Based on the Driving Force-State-Response model, expert weight method and entropy m... [Objective] This study aimed to evaluate the environmental effects coming from land changes in Hotan oasis during 1980-2010. [Method] Based on the Driving Force-State-Response model, expert weight method and entropy method were used to determine weight, and then the composite indexes of environmental effects (CIE for short) were calculated. [Result] During the period from 1980 to 2010, CIE had presented a rising trend whether expert weight method or entropy method in the study area, while the CIE presents downtrend basically in lower reaches. [Conclu- sion] It was the arable land expansion in middle reaches that led to serious land degradation in lower reaches, and may endanger ecosystem safety in Hotan River green corridor. Therefore, it is suggested that the agricultural land use should be restructured, such as reducing the sown areas of some crops with large amount of water consumption. Meanwhile, the effective measures should be taken to distribute water resources and utilize them reasonably. In addition, the oasis-desert ecotone, as well as the groundwater resources, should be also protected. 展开更多
关键词 Comprehensive evaluation environmental effects Land change Hotan Oasis
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Environmental Effects of Returning Rice and Wheat Straw to Fields 被引量:1
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作者 何成芳 朱鸿杰 +2 位作者 孔祥强 李彩丹 闫晓明 《Agricultural Science & Technology》 CAS 2017年第9期1710-1715,共6页
Based on advances in returning rice and wheat straw to fields at home and abroad, environmental physical, chemical and ecological effects of returning rice and wheat straw to fields were analyzed. The results show tha... Based on advances in returning rice and wheat straw to fields at home and abroad, environmental physical, chemical and ecological effects of returning rice and wheat straw to fields were analyzed. The results show that returning straw to fields can enhance soil porosity, reduce soil bulk density, and increase the ca- pacity of soil to preserve water, fertilizer and temperature. Besides, it can improve the content of organic matter, nitrogen, phosphorus and potassium in soil, of which the increase of potassium content is the most obvious. Meanwhile, it can provide energy and nutrients for microorganisms in soil and change the activity of soil enzymes, of which it affects invertase most greatly and enhances the activity of ure- ase but has no effect on neutral phosphatase. In addition, it can enhance the total quantity of microorganisms in soil obviously, and the increase correlates positively with the quantity of straw returning to fields. Finally, returning straw to fields can promote the sustainable development of agriculture. 展开更多
关键词 Rice-wheat rotation Returning straw to fields environmental effects
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The causes and environmental effects of land use conversion during agricultural restructuring in Northeast China 被引量:6
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作者 刘彦随 甘红 +1 位作者 Jay GAO DENG Xusheng 《Journal of Geographical Sciences》 SCIE CSCD 2004年第4期488-494,共7页
During the last decade of the 20th century, extensive conversion inagricultural land use took place in Northeast China. The goal of this study is to ascertain itsspatial distribution and regional differentiation, dete... During the last decade of the 20th century, extensive conversion inagricultural land use took place in Northeast China. The goal of this study is to ascertain itsspatial distribution and regional differentiation, determine its causes, and analyze itsenvironmental impact. Especially we attempt to elucidate how institutional constraints havefacilitated the change at a time of agrarian restructuring when newly emerging free market washybridized with the former planned economy. Information on six categories of land use was mappedfrom interpretation of Landsat TM images recorded in 1990, 1995 and 2000. Most of land use changestook place during the first half of the decade, coinciding with abrupt and chaotic changes ingovernment directives. Farmland was changed mainly to woodland, water body and built-up areas whilewoodland and grassland were converted chiefly to farmland. Spatially, the change from farmland towoodland was restricted to the west of the study area. The change from grassland to farmland tookplace in the grazing and farming interlocked west. These chaotic and occasionally conflictingchanges were largely caused by lack of stability and consistency in agricultural land use policiespromulgated. They have exerted adverse impacts on the local environment, including land degradation,increased flooding, and modified climate regime. 展开更多
关键词 land use conversion agricultural restructuring remote sensing environmental effects northeast China
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Environmental and Health Effects Associated With Harmful Algal Bloom and Marine Algal Toxins in China 被引量:7
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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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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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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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Atomic Level Dispersed Metal–Nitrogen–Carbon Catalyst toward Oxygen Reduction Reaction: Synthesis Strategies and Chemical Environmental Regulation 被引量:3
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作者 Hengbo Yin Huicong Xia +3 位作者 Shuyan Zhao Kexie Li Jianan Zhang Shichun Mu 《Energy & Environmental Materials》 SCIE CSCD 2021年第1期5-18,共14页
For development and application of proton exchange membrane fuel cell(PEMFC) energy transformation technology, the cost performance must be elevated for the catalyst. At present, compared with noble metal-based cataly... For development and application of proton exchange membrane fuel cell(PEMFC) energy transformation technology, the cost performance must be elevated for the catalyst. At present, compared with noble metal-based catalysts, such as Pt-based catalysts, atomically dispersed metal–nitrogen–carbon(M–N–C) catalysts are popularity and show great potential in maximizing active site density, high atom utilization and high activity,making them the first choice to replace Pt-based catalysts. In the preparation of atomically dispersed metal–nitrogen–carbon catalyst, it is difficult to ensure that all active sites are uniformly dispersed, and the structure system of the active sites is not optimal. Based on this, we focus on various approaches for preparing M–N–C catalysts that are conducive to atomic dispersion, and the influence of the chemical environmental regulation of atoms on the catalytic sites in different catalysts. Therefore, we discuss the chemical environmental regulation of the catalytic sites by bimetals, atom clusters, and heteroatoms(B, S, and P). The active sites of M–N–C catalysts are explored in depth from the synthesis and characterization, reaction mechanisms, and density functional theory(DFT)calculations. Finally, the existing problems and development prospects of the current atomic dispersion M–N–C catalyst are proposed in detail. 展开更多
关键词 atomic-level catalyst chemical environmental effects metal-nitrogen-carbon oxygen reduction reaction synthesis strategy
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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:2
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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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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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Environmental load of solid wood floor production from larch grown at different planting densities based on a life cycle assessment 被引量:1
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作者 Siying Hu Xin Guan +1 位作者 Minghui Guo Jinman Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第5期1443-1448,共6页
As one of the main structural units in a building,a solid wood floor has significant strategic research value for low-carbon energy saving.Taking the production line of a solid larch wood floor as a case study,we asse... As one of the main structural units in a building,a solid wood floor has significant strategic research value for low-carbon energy saving.Taking the production line of a solid larch wood floor as a case study,we assessed the environmental load during production based upon a life cycle assessment.Using GaBi 6.0 software,we analyzed the associated carbon sequestration during floor production,with the initial planting density serving as the disturbance factor in a modular analysis.The results indicated that the cutting and finishing steps have relatively intense,negative influences on the environment,whereas transportation,ripping,and trimming do not.Additionally,recycling biomass waste has the potential to reduce greenhouse gas emissions.When the initial planting density was 3.0×3.0 m,carbon sequestration was relatively high.Although the emissions of freshwater pollutants,volatile organic compounds,and fine particulate matter(matter with a 2.5-μm diameter) were comparatively high,the reduction of greenhouse gas emissions was still excellent at this planting density. 展开更多
关键词 environmental effect LARCH Life cycle assessment Planting density Solid wood floor
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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 environmental effect EXCAVATION DEFORMATION Excess porewater pressure
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Episodes of volcanic activity and their environmental effects in the Okinawa Trough during the last 150 ka 被引量:1
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作者 李铁刚 赵京涛 李安春 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第4期363-367,共5页
A piston core Z14-6 was used in this study. The core, 896 cm long, was collected from eastern slope of the Okinawa Trough (27°07'N, 127°27'E, water depth 739m). The δ^18O and δ^13C values of the sedime... A piston core Z14-6 was used in this study. The core, 896 cm long, was collected from eastern slope of the Okinawa Trough (27°07'N, 127°27'E, water depth 739m). The δ^18O and δ^13C values of the sediment bearing planktonic foraminifera G. sacculifer and N. dutertrei were determined; and the abundance of volcanic glass was analyzed. The volcanic glass content high occurred in early stage of polar ice-sheet growth period, or the beginning of cold climate periods corresponding to Milankovitch cycles (Peak Ⅰ, Ⅱ and V are corresponding to the beginnings of oxygen isotopic stages 2, 4 and 6, and Peak Ⅲ and Ⅳ are matching oxygen isotopic stage 5b-5d.). It might be possible that volcanic episodes and climate changes were responding to orbital forcing in the Okinawa Trough in late Quaternary. The δ^18O difference between N. dutertrei and G. sacculifer shows no clear correlation to the volcanic glass content high, which suggests that the volcanic eruptions did not influence the structure of upper water column. However, the low δ^13C difference between G. sacculifer and N. dutertrei is coeval with the volcanic glass high or sub-high content. This fact suggests that volcanic eruptions might influence the reduction in vertical nutritional gradient and carbon cycle process in upper water column. A possible mechanism is that huge quantity of ash and dust had weakened the light intensity, resulting in photosynthesis reduction, productivity decrease, and biological pumping. 展开更多
关键词 environmental effects volcanic activity Okinawa Trough Late Quaternary
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ENVIRONMENTAL IMPACT ASSESSMENT OF CEMENT—CONCRETE SYSTEM 被引量:1
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作者 刘顺妮 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2000年第4期7-11,共5页
In this paper. a lije-cycle assessment methodology is used to evaluate the environmental cffects of cement-concrete system. The production factors notably affecting environment are obtained and the way in proving envi... In this paper. a lije-cycle assessment methodology is used to evaluate the environmental cffects of cement-concrete system. The production factors notably affecting environment are obtained and the way in proving environmental effects is indicated. 展开更多
关键词 lije-cycle assessment environmental effect cement-concrete system
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Study on the Environmental Impact of Oil and Gas Field Development on the Ecological Red Line Area 被引量:1
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作者 Yunshi XIONG Zhihong GUO +1 位作者 Tao LIANG Qichen GAO 《Meteorological and Environmental Research》 CAS 2020年第3期70-73,80,共5页
To cooperate with the five ministries and commissions of the state to carry out joint investigation on the environmentally sensitive areas involved in oil and gas exploration and development,for the problems found in ... To cooperate with the five ministries and commissions of the state to carry out joint investigation on the environmentally sensitive areas involved in oil and gas exploration and development,for the problems found in survey,containing complex type and numerous amount of ecologically sensitive space and ecological red line involved in oil and gas field enterprises,scientific nature of delimitation,lack of strong support of laws and regulations for forced withdrawal of oil and gas production facilities in these areas,some countermeasures and suggestions were proposed,such as further evaluating and combing scope and functional zoning of existing environmentally sensitive areas and ecological red lines,treating differently,enhancing pertinence of prohibition in ecologically sensitive regions,declining blindness of the withdrawal of oil and gas facilities in environmentally sensitive areas,strengthening seriousness of approval of exploration and mining rights of oil and gas resources,and establishing strategic reserve exploration and hierarchical development mechanism. Moreover,oil and gas field enterprises should integrate more efforts to ① accelerate to find out the current situation of environmental quality,② adhere to developing in protection,and protecting in development,③ increase attention and participation strengthen of providing technical support for national oil and gas exploration and development strategy evaluation,④ accelerate communication and docking with local governments on the ecological red line,⑤ actively strive to be included in the positive list management of local governments,⑥ accelerate to establish and perfect primary database of oil and gas production and facilities construction,and ⑦ document management information system of the ecological red line. 展开更多
关键词 Oil and gas fields Exploration and development Ecological red line environmentally sensitive area environmental effect
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Environmental Effects of Foreign Trade and Its Spatial Variations in Mid-eastern Provinces and Cities of China
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作者 JIN Xianfeng DONG Suocheng +4 位作者 LUO Lingjun LI Yu YUAN Chao SHU Kesheng CHEN Jiaquan 《Chinese Geographical Science》 SCIE CSCD 2012年第5期626-636,共11页
The studies on environmental effects of foreign trade and its spatial variations are helpful to design and implement environmental protection countermeasures.In order to eliminate the adverse effects of insufficient o... The studies on environmental effects of foreign trade and its spatial variations are helpful to design and implement environmental protection countermeasures.In order to eliminate the adverse effects of insufficient observation values on the accuracy of regression results and dynamic information quantity of fitting equation during empirical study,panel data of the mid-eastern provinces and cities of China from 1985 to 2007 were selected based on the adjustment of classical regression model in this paper.Panel unit root test and panel cointegration analysis method were applied to investigating the environmental effects of foreign trade and its spatial variations in the mid-eastern provinces and cities of China and its three groups divided by foreign trade dependence.The results show that all scale effects are positive,while all technical effects are negative and unable to counteract positive scale effects.Foreign trade development is regarded as an important cause for outstanding eco-environmental problems in the mid-eastern provinces and cities of China.Total effects and structural effects are significantly different among different groups because of spatial variations in environmental policies,export destinations,source of FDI,etc.Following the principle of′coordinating generality and considering differences comprehensively′,it is essential to issue a series of policies and countermeasures corresponding to differences in regional environmental effect of foreign trade,in order to coordinate the relationship between foreign trade development and eco-environment in each region. 展开更多
关键词 mid-eastern provinces and cities of China foreign trade environmental effect spatial variation cointegra-tion analysis
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Estimation of Annual Energy Output from BCM Tidal Barrage and the Corresponding Marine Environmental Impact
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作者 YU Huaming WANG Lu +4 位作者 KUANG Liang YU Haiqing SUN Yuchen QU Yuhuan WU Xin 《Journal of Ocean University of China》 SCIE CAS 2016年第2期209-218,共10页
Based on the finite-volume coastal ocean model (FVCOM), a three-dimensional numerical model FVCOM was built to simulate the ocean dynamics in pre-dam and post-dam conditions in Bachimen (BCM). The domain decomposi... Based on the finite-volume coastal ocean model (FVCOM), a three-dimensional numerical model FVCOM was built to simulate the ocean dynamics in pre-dam and post-dam conditions in Bachimen (BCM). The domain decomposition method, which is effective in describing the conservation of volume and non-conservation of mechanical energy in the utilization of tidal energy, was employed to estimate the theoretical tidal energy resources and developable energy resources, and to analyze the hydrodynamic effect of the tidal power station. This innovative approach has the advantage of linking physical oceanography with engineering problems. The results indicate that the theoretical annual tidal energy resources is about 2x 108 kwh under the influence of tidal power station; Optimized power installation is confirmed according to power generation curve from numerical analysis; the developable resources is about 38.2% of theoretical tidal energy resources with the employment of one-way electricity generation. The electricity generation time and power are 3479 hours and 2.55~104KW, respectively. The power station has no effect on the tide pattern which is semi-diumal tide in both two conditions, but the amplitudes of main constituents apparently decrease in the area near the dam, with the ME decreasing the most, about 62.92 cm. The tidal prism shrinks to 2.28×107 m3, but can still meet the flow requirement for tidal power generation. The existence of station increases the flow rate along the waterway and enhances the residual current. There are two opposite vortexes formed on the east side beside the dam of the station, which leads to pollutants gathering. 展开更多
关键词 tidal energy resources tidal developable resources numerical simulation marine environmental effects
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