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ANALYSIS ON THE SOURCE AND SINK OF KINETIC ENERGY OF ATMOSPHERIC 30—60 DAY PERIOD OSCILLATION AND THE PROBABLE CAUSES 被引量:3
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作者 李清泉 朱乾根 《Acta meteorologica Sinica》 SCIE 1995年第4期420-431,共12页
Based on ECMWF daily grid point data in summer (May—August),1981,the distribution features of the source and sink of kinetic energy of atmosphere 30—60 day oscillation,including its horizontal distribution character... Based on ECMWF daily grid point data in summer (May—August),1981,the distribution features of the source and sink of kinetic energy of atmosphere 30—60 day oscillation,including its horizontal distribution characteristics and its vertical structure characteristics,are investigated systematically with diagnostic analysis methods over a latitude belt between 80°N and 60°S.Also,the probable reasons for the existence of the source and sink of low frequency kinetic energy (LFKE) are discussed preliminarily.Results show that the horizontal distribution of the sources and sinks of kinetic energy of atmospheric 30—60 day oscillation is extremely different.The significant sources and sinks of LFKE mainly exist in the oceans and the coastal regions of continents or islands in the mid-high latitudes.It is also found that,in the vertical direction,the sources and sinks of kinetic energy of 30—60 day oscillation display barotropic structure in the mid-high latitudes of both hemispheres,but dispaly baroclinic structure in the equtorial region,and in the horizontal direction, the sources and sinks mainly display zonal wave-like distribution.The source and sink of LFKE are determinded by ageostrophic wind effect,frictional effect,interaction between sub-grid-scale systems,nonlinear interaction,and the flux-divergence of LFKE transported by transient wind. There are some regional reasons for the generation of sources and sinks which are not completely identical in different areas. 展开更多
关键词 low frequency oscillation atmospheric energy source and sink of kinetic energy 30—60 day oscillation
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Non-Point-Source Nitrogen and Phosphorus Loadings from a Small Watershed in the Three Gorges Reservoir Area 被引量:25
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作者 ZHU BO WANG Zhenhua +1 位作者 WANG Tao DONG Zhixin 《Journal of Mountain Science》 SCIE CSCD 2012年第1期10-15,共6页
Non-point-source pollution has become a major threat to the water quality of the Three Gorges Reservoir(TGR);however,nutrient loadings from terrestrial sources are unclear due to a lack of in situ monitoring.A represe... Non-point-source pollution has become a major threat to the water quality of the Three Gorges Reservoir(TGR);however,nutrient loadings from terrestrial sources are unclear due to a lack of in situ monitoring.A representative small watershed in the central part of the TGR area was selected to monitor the loss of nitrogen(N) and phosphorous(P) continuously along with the runoff from 2007 through 2009 to understand the exact sources and loadings.Results show that the non-point-source nitrogen and phosphorus comes mainly from the storm runoff from residential areas,citrus orchards and sloping croplands,which contributes up to 76% of the loadings in this watershed.Thus,a crucial measure for controlling non-point-source pollution is to intercept storm runoff from the three sources.Paddy fields provide a sink for non-point-source N and P by intercepting the runoff and sediment along with their different forms of nitrogen and phosphorus.The N and P removal efficiency by paddy fields from residential areas is within the range of 56% to 98%.Paddy fields are an important land-use option for reducing the non-point-source loading of N and P in the TGR area. 展开更多
关键词 Non-point-source pollution source and sink Nitrogen Phosphorus Paddy fields Three Gorges Reservoir area China
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Effects of carbon sink fisheries ecosystems
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作者 周胜杰 贾婷婷 +5 位作者 李连星 张扬 刘兴 陈成勋 王庆奎 孙学亮 《Marine Science Bulletin》 CAS 2015年第2期89-96,共8页
Currently, due to the burning of fossil fuels and changes in land use patterns, a lot of CO2 (carbon dioxide) emissions into the air, the amount of CO2 in the air is extremely increased. According to the research CO... Currently, due to the burning of fossil fuels and changes in land use patterns, a lot of CO2 (carbon dioxide) emissions into the air, the amount of CO2 in the air is extremely increased. According to the research CO2 is the main component of greenhouse gases and the main culprit of causing the greenhouse effect. The ocean is a huge repository of carbon, water can dissolve a large amount of CO2, in the ocean, a large number of plants and planktonic algae absorb CO2 to produce 02, It is a very large gathering place (sink). At the same time, CO2 aggregation in the ocean seawater acidity increases, impact on fishery resources, sources and sinks of CO2 were discussed in the paper. 展开更多
关键词 source and sink greenhouse gases ecologicalsystem fishery resources
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The Dynamics of Changes in Starch and Lipid Droplets and Sub-Cellular Localization of β-Amylase During the Growth of Lily Bulbs 被引量:1
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作者 WU Sha-sha WU Jin-di +2 位作者 JIAO Xue-hui ZHANG Qi-xiang LV Ying-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第4期585-592,共8页
The ultra-structure of mother and outer daughter scales of Lilium Oriental hybrid Sorbonne were studied using transmission electron microscope to examine the sub-cellular localization of starch and lipid droplets duri... The ultra-structure of mother and outer daughter scales of Lilium Oriental hybrid Sorbonne were studied using transmission electron microscope to examine the sub-cellular localization of starch and lipid droplets during growth and development from shoot emergence to senescence.The contents of starch granules and lipid droplets in the cell of the mother scales decreased significantly from shoot emergence to anthesis,indicating that these scales served as a source for growth and development.After flowering,the number of starch granules and lipid droplets increased dramatically,and finally the cells were filled with the above molecules indicating that the bulb becomes a major sink during bulb enlargement.Ultrastructure observation also showed that symplastic pathway is the main pathway in cells in the exchange and transportation of material during bulb development.The activity of β-amylase,one of the key enzymes catalyzing starch breakdown,showed a similar trend.The enzyme sub-cellular localization via immune-gold electron-microscopy showed that βamylase was predominantly located together with starch granules,while the gold particles were scarcely found in other sub-cellular compartments.The result suggested that this enzyme is compartmented together with its functional substrate supporting its function in catalyzing starch breakdown in living plant cells. 展开更多
关键词 Lilium Oriental hybrids BULB scale source and sink ULTRA-STRUCTURE Β-AMYLASE sub-cellular localization
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Temporal and spatial variations of carbon isotope signature reveal substantial contribution of bracts and internode assimilates to grain filling of japonica rice
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作者 Mengjiao Jiang Hongfa Xu +4 位作者 Nianfu Yang Ganghua Li Yanfeng Ding Matthew J.Paul Zhenghui Liu 《The Crop Journal》 SCIE CSCD 2021年第2期271-281,共11页
Carbon isotope composition(δ^(13)C)of a plant organ is an inherent signature reflecting its physiological property,and thus is used as an integrative index in crop breeding.It is also a non-intrusive method for quant... Carbon isotope composition(δ^(13)C)of a plant organ is an inherent signature reflecting its physiological property,and thus is used as an integrative index in crop breeding.It is also a non-intrusive method for quantifying the relative contribution of different source organs to grain filling in cereals.Using the samples collected from two-year field and pot experiments with two nitrogen(N)fertilization treatments,we investigated the temporal and spatial variations of δ^(13)C in source organs of leaf,sheath,internode,and bracts,and in sink organ grain.Constitutive nature of δ^(13)C was uncovered,with an order of leaf(−27.84‰)<grain(−27.82‰)<sheath(−27.24‰)<bracts(−26.81‰)<internode(−25.67‰).For different positions of individual organs within the plant,δ^(13)C of the leaf and sheath presented a diminishing trend from the top(flag leaf and its sheath)to the bottom(the last leaf in reverse order and its sheath).No obvious pattern was found for the internode.For temporal variations, δ^(13)C of the leaf and sheath had a peak(the most negative)at 10 days after anthesis(DAA),whereas that of the bracts showed a marked increase at the time point of anthesis,implying a transformation from sink to source organ.By comparing the δ^(13)C in its natural abundance in the water-soluble fractions of the sheath,internode,and bracts with the δ^(13)C in mature grains,the relative contribution of these organs to grain filling was assessed.With reference to the leaf,the internode accounted for as high as 32.64%and 42.56%at 10 DAA and 20 DAA,respectively.Meanwhile,bracts presented a larger contribution than the internode,with superior bracts being higher than inferior bracts.In addition,N topdressing reduced the contribution of the internode and bracts.Our findings clearly proved the actual significance of non-foliar organs of the internode and bracts for rice yield formation,thus extending our basic knowledge of source and sink relations. 展开更多
关键词 japonica rice Carbon isotope composition(δ^(13)C) Temporal and spatial variations source and sink relation Grain yield formation
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Evaluation of the simulation capability of the Wavewatch Ⅲ model for Pacific Ocean wave 被引量:12
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作者 BI Fan SONG Jinbao +1 位作者 WU Kejian XU Yao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第9期43-57,共15页
Wave climate analysis and other applications for the Pacific Ocean require a reliable wave hindcast. Five source and sink term packages in the Wavewatch III model (v3.14 and v4.18) are compared and assessed in this ... Wave climate analysis and other applications for the Pacific Ocean require a reliable wave hindcast. Five source and sink term packages in the Wavewatch III model (v3.14 and v4.18) are compared and assessed in this study through comprehensive observations, including altimeter significant wave height, advanced synthetic aperture radar swell, and buoy wave parameters and spectrum. In addition to the evaluation of typically used integral parameters, the spectra partitioning method contributes to the detailed wave system and wave maturity validation. The modified performance evaluation method (PS) effectively reduces attribute numbers and facilitates the overall assessment. To avoid possible misleading results in the root mean square error-based validations, another indicator called HH (indicating the two authors) is also calculated to guarantee the consistency of the results. The widely used Tolman and Chalikov (TC) package is still generally efficient in determining the integral properties of wave spectra but is physically deficient in explaining the dissipation processes. The ST4 package performs well in overall wave parameters and significantly improves the accuracy of wave systems in the open ocean. Meanwhile, the newly published ST6 package is slightly better in determining swell energy variations. The two packages (ACC350 and BIA) obtained from Wavewatch III v3.14 exhibit large scatters at different sea states. The three most ideal packages are further examined in terms of reproducing wave- induced momentum flux from the perspective of transport. Stokes transport analysis indicates that ST4 is the closest to the NDBC-buoy-spectrum-based transport values, and TC and ST6 tend to overestimate and underestimate the transport magnitude, respectively, in swell mixed areas. This difference must be considered, particularly in air-wave-current coupling research and upper ocean analysis. The assessment results provide guidance for the selection of ST4 for use in a background Pacific Ocean hindcast for high wave climate research and China Sea swell type analysis. 展开更多
关键词 Wavewatch III EVALUATION Pacific Ocean source and sink term packages wave-induced flux Stokes transport
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Carbon transportation,transformation,and sedimentation processes at the land-river-estuary continuum
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作者 Yang Gao Junjie Jia +3 位作者 Yao Lu Kun Sun Jing Wang Shuoyue Wang 《Fundamental Research》 CSCD 2024年第6期1594-1602,共9页
In terrestrial ecosystems,carbon(C)transportation and C pool transformation processes both occur at the landriver-estuary continuum.Moreover,C budget and C balance processes are generally critical in achieving the C n... In terrestrial ecosystems,carbon(C)transportation and C pool transformation processes both occur at the landriver-estuary continuum.Moreover,C budget and C balance processes are generally critical in achieving the C neutrality of terrestrial ecosystems.This study analyzes key C transportation processes at multiple interfaces that collectively constitute the land-river-estuary continuum,discusses C transportation and sedimentation processes at the land-river interface,and reveals aquatic plant C sequestration coupling processes and associated productivity.Transformation mechanisms of inorganic-organic C pools are also investigated here as well as a systematic evaluation of C transport flux within the different interfaces that constitute the land-river-estuary continuum.Results show that the net C sink of terrestrial ecosystems was 1.70 Pg C yr^(−1),wherein the gross primary productivity(GPP)of global terrestrial vegetation reached 123 Pg C yr^(−1),while rock weathering also consumed 0.30 Pg C yr^(−1)of atmospheric carbon dioxide(CO_(2)).Subsequently,the C transported by the land-river-estuary continuum reached 1.70 Pg C yr^(−1).During this process,0.20 Pg C is deposited and buried in inland water and 1.00 Pg C escapes from inland water systems each year.Therefore,only 0.85 Pg C is transported to the estuary.Finally,this study clarifies control mechanisms of C transportation and transformation processes at the land-river-estuary continuum.The aim of this study is to provide an important scientific basis for the quantitative analysis of C sources and sinks at the land-river-estuary continuum and C neutrality of the biosphere. 展开更多
关键词 Land-river-estuary continuum Carbon neutrality Carbon source and sink Carbon transportation Carbon sedimentation Carbon cycle
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PARAMETERIZATION OF MOBILIZATION AND TRANSPORT OF SAND-DUST DURING BLACK STORM AND MESOSCALE NUMERICAL EXPERIMENTS 被引量:1
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作者 刘春涛 程麟生 《Acta meteorologica Sinica》 SCIE 1999年第3期316-330,共15页
The typical black storms or sand-dust storms in the northwestern China are generated and developed through an interaction between the specific large scale circulation pattern and mesoseale systems.The passing by/over ... The typical black storms or sand-dust storms in the northwestern China are generated and developed through an interaction between the specific large scale circulation pattern and mesoseale systems.The passing by/over a huge sand-abundant desert of a strong cold front with intensive frontal zone at mid and lower levels is a necessary condition for the formation and development of a black storm or a severe sand-dust storm.In order to investigate the mechanism of the sand-dust mobilization,transport and sedimentation during the black or sand-dust storms,a parameterization scheme of sand-dust source-sink terms and an equation of transport for the sand-dust were proposed and incorporated into the MM4 mesoscale model.The modified MM4 model was applied to the“May 1993”black storm case and succeeded in reproducing the evolution of the weather systems associated with the black-storm,the sand-dust concentration at surface layer and its vertical distribution,and the sand-dust sedimentation and transport.Our results show that the numerical simulating method by using a mesoscale model,with inclusion of an equation of the sand-dust transport and a parameterization scheme of the sand-dust source-sink terms,is a promising approach to study the mechanism for sand-dust mobilization,transport and sedimentation during a sand-dust storm event. 展开更多
关键词 black storm mobilization and transport of sand-dust parameterization of sand-dust source and sink terms numerical simulation
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CH_(4) and C0_(2) observations from a melting high mountain glacier,Laohugou Glacier No.12 被引量:1
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作者 Zhi-Heng DU Lei WANG +9 位作者 Zhi-Qiang WEI Jing-Feng LIU Peng-Lin LIN Jia-Hui LIN Yan-Zhao LI Zi-Zhen JIN Ji-Zu CHEN Xiao-Xiang WANG Xiang QIN Cun-De XIAO 《Advances in Climate Change Research》 SCIE CSCD 2022年第1期146-155,共10页
With global warming,glaciers in the high mountains of China are retreating rapidly.However,few data have been reported on whether greenhouse gases from these glaciers are released into the atmosphere or absorbed by gl... With global warming,glaciers in the high mountains of China are retreating rapidly.However,few data have been reported on whether greenhouse gases from these glaciers are released into the atmosphere or absorbed by glacial meltwater.In this study,we collected meltwater and ice samples from Laohugou Glacier No.12 in western China and measured CH_(4)and CO_(2)concentrations.Meltwater from the glacier terminus was continually sampled between 3 and 5 August 2020 to measure CH_(4)and CO_(2)concentrations.The results demonstrated that meltwater is a source of CH_(4)because the average saturations are over 100%.It could be con eluded that CH_(4)in the atmosphere can be released by glacial meltwater.However,the CO_(2)saturations are various,and CO_(2)fluxes exhibit positive(released CO_(2))or negative(absorbed CO_(2))values because the water and atmospheric conditions are variable.More importantly,the CH_(4)and CO_(2)concentrations were higher in meltwater samples from the glacier terminus than in samples from the surface ice(including an ice core)and a surface stream.Although the meltwater effect from the upper part of the glacier cannot be excluded,we speculated that subglacial drainage systems with an anaerobic environment may represent the CH_(4)source,but it needs to be further investigated in the future.However,high mountain glaciers are currently ignored in global carbon budgets,and the increased melting of glaciers with global warming may accelerate the absorption of much more CO_(2)and lead to the release of CH_(4). 展开更多
关键词 CO_(2) CH_(4) source and sink:Subglacial drainage systems Laohugou glacier No.12
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