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面积权衡劈分方法计算单井地质储量 被引量:15
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作者 徐春华 范小秦 +2 位作者 池建萍 邢舟 孙涛 《特种油气藏》 CAS CSCD 2005年第2期45-48,共4页
从二中西区单井控制含油面积的井点面积权衡法的储量计算实例出发,具体探讨了单井地质储量和井点剩余油分布计算方法对剩余油计算的可行性和优点。该方法尤其适用于非均质性极强的砾岩油藏,在老区油藏挖潜研究中具有较强的可操作性和实... 从二中西区单井控制含油面积的井点面积权衡法的储量计算实例出发,具体探讨了单井地质储量和井点剩余油分布计算方法对剩余油计算的可行性和优点。该方法尤其适用于非均质性极强的砾岩油藏,在老区油藏挖潜研究中具有较强的可操作性和实用性。 展开更多
关键词 面积权衡劈分方法 单井地质储量 剩余油计算 中西区
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Research on the extension of Tamarix shrubs resulted from devel-opment projects in arid area 被引量:2
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作者 黄培祐 高瑞如 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期45-48,J002,共5页
Tamarix plant is widely distributed in the arid areas of China for its great tolerance of draught, salt and alkali and attracts more attention by its strong capacity in windbreak and sand-fixations. “Tamarix dunes” ... Tamarix plant is widely distributed in the arid areas of China for its great tolerance of draught, salt and alkali and attracts more attention by its strong capacity in windbreak and sand-fixations. “Tamarix dunes” constitute special desert bio-landscape in arid area. During last several decades,Tamarix shrubs declined and “Tamarix dunes” were also severely destroyed due to the land exploitation and serious deforestation, etc. From the 1980s until now, the extending phenomenon ofTamarix shrubs caused by developmental projects such as building highway, railway was studied in the western dry area of China, including western section of Hexi Corridor of Gansu, railroads and highways around the two greatest basin in Xinjiang and interior regions in Gurbantonggut desert, through on-the-spot survey along the transportation lines and setting up sampling plots along the roads. It was found that large quantities ofTamarix plants grow in the catchment area of low-lying lands that were formed by bulldozer operation during road building period. The extension ofTamarix shrubs caused by engineering was similar to that of the other section of the area to some extent, but went beyond the original distribution. This extension is beneficial to the ecological restoration and re-vegetation of western region of China and plays an important role in control of the sandstorms and improvement of ecological environments. As a result, it is necessary to make a further study on the extending phenomenon ofTamarix shrubs and to seek approach to promote wider extension ofTamarix shrubs in suitable habitats. Key words Arid area - Tamarix - Development engineering - Vegetation extension CLC number S718.541 Document code A Article ID 1007-662X(2004)01-0045-04 Foundation Item: This study is supported by key projects of National Natural Science Foundation (39730100), National Foundation (30070640) and part of Project 973(G19990435).Biography: Huang Pei-You (1936-), Male, Professor in College of Life Science and Technology, Xinjiang University, Urumqi, 830046Responsible editor: Chai Ruihai 展开更多
关键词 Arid area TAMARIX Development engineering Vegetation extension
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Assessment of Climate for Agricultural Suitability and Optimal Allocation of Agricultural Production in the Guanzhong Region, Shaanxi Province 被引量:2
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作者 杨忍 刘彦随 任志远 《Agricultural Science & Technology》 CAS 2012年第11期2379-2384,2448,共7页
Based on spatial climatic data of agriculture and the experiment data, the models of agro-ecological assessment of climate for agricultural suitability in this study were developed using the fuzzy mathematical method.... Based on spatial climatic data of agriculture and the experiment data, the models of agro-ecological assessment of climate for agricultural suitability in this study were developed using the fuzzy mathematical method. Three coefficients, in- cluding the resource coefficient (Cr), the efficiency coefficient (Ce), and the utility co- efficient (K), were used in the models, which were calculated based on temperature, moisture, and sunshine duration data of Guanzhong region, Shaanxi Province. The results indicated that resource coefficient was higher in west of the region than that in east, and higher in south (especially in the Central Shaanxi Plain) than that in the Weibei plateau. The value of Cr changed from 6.5 to 9.2 from north to plain area. Spatial change of efficiency coefficient was obvious, lower in the northeast than in the central plain, and the value of Ce changed from 2.3 to 6.5 from the northeast to the central plain. As for utility coefficient, it was lower in northeastern part of the Weibei plateau and in southern mountain areas than that in the central plain, showing significant latitudinal zonality. Furthermore, the value of K increased from 0.35 to 0.78 from northeast to the central plain, and decreased from 0.78 to 0.53 from the central plain to southern mountain areas. These indicated that climate resource in the central plain region was more abundant and potential, compared with other regions. GuanZhong region was classified into three larger agricultural zones and three small independent zones, according to agro-ecological assessment. Light, heat and water resources should be made use of in an efficient way in spatial allo- cation of agricultural production. For example, water facilities should also be im- proved in Weibei plateau region where highly-qualified fruit should be enhanced and fruit processing industrial chain should be shaped. Large-scale production area of wheat should be increased in central irrigation region and more vegetable bases should be developed around large and medium-scale cities. Thanks for outstanding water conservation function, the three-dimensional agriculture including medicine and other sideline production should be developed in Qinling Mountains and the special- ized commercial agriculture should be accelerated in independent small zones, ac- cording to local conditions. In the research, different crop varieties were developed in corresponding regions as per current eco-climatic conditions. 展开更多
关键词 Assessment of climate for agricultural suitability Optimal allocation ofagricultural production Guanzhong region
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Several Fossil Woods from Mesozoic of Western Liaoning Province, Northeast, China 被引量:19
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作者 段淑英 《Acta Botanica Sinica》 CSCD 2000年第2期207-213,共7页
The author described some new species and genera of the fossil woods from Mesozoic of Western Liaoning besides Xenoxylon latiporosum (Cramer) Gothan, X. hopeiense Chang, X. liaoningense Duan et Wang, X. yixia... The author described some new species and genera of the fossil woods from Mesozoic of Western Liaoning besides Xenoxylon latiporosum (Cramer) Gothan, X. hopeiense Chang, X. liaoningense Duan et Wang, X. yixianense Zhang et Shang, Protopiceoxylon yizhouense Duan et Cui. They are Protopiceoxylon chaoyangense Duan sp. nov., Araucarioxylon batuense Duan sp. nov., Taxoxylon liaoxiense Duan sp. nov. and an old species Araucarioxylon sidugawaense Shimakura. 展开更多
关键词 Protopiceoxylon Araucarioxylon Taxoxylon
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Reforestation Programs in Southwest China:Reported Success,Observed Failure, and the Reasons Why 被引量:12
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作者 Christine Jane Trac Stevan Harrell +1 位作者 Thomas M. Hinckley Amanda C. Henck 《Journal of Mountain Science》 SCIE CSCD 2007年第4期275-292,共18页
Ever since the disastrous floods of 1998, the Chinese government has used the Natural Forest Protection and Sloping Land Conversion Programs to promote afforestation and reforestation as means to reduce runoff, contro... Ever since the disastrous floods of 1998, the Chinese government has used the Natural Forest Protection and Sloping Land Conversion Programs to promote afforestation and reforestation as means to reduce runoff, control erosion, and stabilize local livelihoods. These two ambitious programs have been reported as large-scale successes, contributing to an overall increase in China’s forest cover and to the stated goals of environmental stabilization. A small-scale field study at the project level of the implementation of these two programs in Baiwu Township, Yanyuan County, Sichuan, casts doubt upon the accuracy and reliability of these claims of success; ground observations revealed utter failure in some sites and only marginal success in others. Reasons for this discrepancy are posited as involving ecological, economic, and bureaucratic factors. Further research is suggested to determine whether these discrepancies are merely local aberrations or represent larger-scale failures in reforestation programs. 展开更多
关键词 FORESTS AFFORESTATION REFORESTATION grain-to-green natural forest protection plan China SICHUAN Liangshan
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Characteristics of Extreme Temperature Event and Its Response to Regional Warming in Northwest China in Past 45 Years 被引量:17
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作者 YANG Jinhu REN Chuanyou JIANG Zhihong 《Chinese Geographical Science》 SCIE CSCD 2008年第1期70-76,共7页
Using the daily maximum and minimum temperature dataset from 128 stations from 1960 to 2004 in Northwest China,daily extreme high temperature(EHT)and extreme low temperature(ELT)thresholds were deter-mined by centesim... Using the daily maximum and minimum temperature dataset from 128 stations from 1960 to 2004 in Northwest China,daily extreme high temperature(EHT)and extreme low temperature(ELT)thresholds were deter-mined by centesimal method for different stations at first,then yearly EHT and ELT events were counted up in differ-ent stations,and the characteristics of their spatio-temporal distribution were diagnosed at last.The study drew follow-ing conclusions:1)The consistent anomaly distribution characteristic was the most important mode of the EHT and ELT events in Northwest China.2)The spatial distribution of the EHT and ELT events can be divided into five sub-regions,namely,the north of Qinghai and west of Gansu,the north of Xinjiang,the south of Xinjiang,the east of Northwest China and the south of Qinghai.3)The EHT events showed remarkable increasing trend in all of five sub-regions,but only in the north of Qinghai and west of Gansu area,sudden change phenomenon occurred;the ELT events showed decreasing trend in all of five sub-regions,and sudden change phenomenon occurred in Northwest China except for south of Qinghai.4)In all of five sub-regions the EHT events showed remarkable 12-14yr period os-cillation,and the ELT event showed significant 13-15yr and 7-8yr period oscillation.5)The EHT and ELT events displayed remarkable positive and negative responses to regional warming of Northwest China respectively. 展开更多
关键词 extreme temperature response to warming Northwest China
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Nitrate Accumulation in Soil Profile of Dry Land Farming in Northwest China 被引量:25
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作者 FAN Jun, HAO Ming-De and SHAO Ming-AnState Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, the Chinese Academy of Sciences, Yangling 712100 (China). 《Pedosphere》 SCIE CAS CSCD 2003年第4期367-374,共8页
A long-term fertilizer experiment on dry land of the Loess Plateau, northwestChina, has been conducted since 1984 to study the distribution and accumulation of NO_3-N down to adepth of 400 cm in the profile of a coars... A long-term fertilizer experiment on dry land of the Loess Plateau, northwestChina, has been conducted since 1984 to study the distribution and accumulation of NO_3-N down to adepth of 400 cm in the profile of a coarse-textured dark loessial soilafter continuous winter wheatcropping. Thirteen fertilizer treatments consisted of four levels of N and P applied alone or incombination. Annual N and P (P_2O_5) rates were 0, 45, 90, 135 and 180 kg ha^(-1). After 15successive cropping cycles, the soil samples were taken from each treatment for analysis of NO_3-Nconcentration. The results showed that NO_3-N distribution in the soil profile was quite differentamong the treatments. The application of fertilizer N alone resulted in higher NO_3-N concentrationin the soil profile than the combined application of N and P, showing that application of P couldgreatly reduce the NO_3-N accumulation. With an annual application of 180 kg N ha^(-1) alone, a peakin NO_3-N accumulation occurred at 140 cm soildepth, and the maximum NO_3-N concentration in thesoils was 67.92 mg kg^(-1). The amount of NO_3-N accumulated in the soil profile decreased as thecumulative N uptake by the winter wheat increased. Application of a large amount of N resulted inlowerN recoveries in winter wheat and greater NO_3-N accumulation in soil profile. KO_3-N did notenter underground water in the study region; therefore, there is no danger of underground waterpollution. Amount of NO_3-N accumulation can be predicted by an equation according to annual N and Prates based on the results of this experiment. 展开更多
关键词 dry land long-term fertilizer experiment NO_3-N accumulation WHEAT
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Ecology of macrozoobenthic communities in two plateau lakes of Southwest China 被引量:5
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作者 崔永德 王洪铸 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第4期345-352,共8页
Ecological studies on macrozoobenthos were conducted in two small plateau lakes in the Yunnan-Guizhou Plateau, Southwest China: Xingyun Lake (XL), a eutrophic lake whose main source of primary production was phytop... Ecological studies on macrozoobenthos were conducted in two small plateau lakes in the Yunnan-Guizhou Plateau, Southwest China: Xingyun Lake (XL), a eutrophic lake whose main source of primary production was phytoplankton (Chl α=99.76±24.01 μg/L), and Yangzong Lake (YL), a mesotrophic lake. Sampling was carried out from October 2002 to May 2004. Altogether 23 benthic taxa were identified in XL and 21 taxa in YL. The density of benthos in XL was much lower than that in YL, but the biomass was about equal in the two lakes, being I 423 ind/m^2 and 8.71 g/m^2 in XL and 4 249 ind/m^2 and 8.60 g/m^2 in YL. The dominant species were Limnodrilus hoffmeisteri, Branchiura sowerbyi, Aulodrilus pluriseta and Chironomus sp. in XL and Limnodrilus hoffrneisteri, Aulodrilus pluriseta and Bellamya sp. in YL. Seasonal fluctuation occurred, showing richer species in summer and winter, but the density and biomass varied in different ways in the two lakes. Analyses on functional feeding groups indicate that collector-gatherers were predominant, but the relative abundances of other groups were different. Stepwise multiple regression analysis demonstrated that the water depth, conductivity and chlorophyll a were the key factors affecting macrozoobenthic abundance in the lakes. 展开更多
关键词 plateau lakes macrozoobenthos taxonomic composition standing crop functional feeding group environmental analysis
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STUDY ON INDEX SYSTEM OF ASSESSMENT OF PUBLIC DISASTER PERCEPTION IN THE WESTERN CHINA 被引量:19
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作者 ZHOUOi LIJing-yi ZHAOJing-bo 《Chinese Geographical Science》 SCIE CSCD 2003年第3期284-288,共5页
The study on humanity response to global environment change is a new direction in the research of global change science, of which an important aspect is to study the adaptation strategies of human being to environment... The study on humanity response to global environment change is a new direction in the research of global change science, of which an important aspect is to study the adaptation strategies of human being to environmental changes in different regions. One reasonable and scientific adaptation strategy is based on not only scientific assessment of the impact of environmental change on society, but also correct estimation of the public perception of environmental change, whereas the research on the latter is terribly weak. This paper intends to understand the personality difference in public perception of environment in the western China primarily by establishing the assessment index system of nation environmental perception and analyzing the results of questionnaire survey in some regions of Shaanxi Province. The conclusions are as follows: 1) The state of public perception of disaster is one of the foundations of constituting and enforcing reasonable adaptation strategy to environmental change. 2) The personality differences of public perception of disaster appear as follows: female disaster perception is stronger than male;the order of disaster perception from strong to weak from the point of age characteristics is 20-30, 0-20, 40-50, 30-40, 50-60, 60 year old or over in turns; the order of disaster perception from strong to weak from the point of educational characteristics is senior high school, college, illiterate, junior high school, primary school, in turns; the order of disaster perception from strong to weak from the point of occupation characteristics is student, farmer, teacher, worker and functionary, in turns; the order of disaster perception from strong to weak from the point of habitat characteristics is city, countryside, towns, and metropolis in turns. 展开更多
关键词 global change disaster perception disaster reduction strategy western China
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Methodological Framework for a Multi-Scale Study on Hydrological Processes and Soil Erosion in Subtropical Southeast China 被引量:8
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作者 H. ZEPP TANG Jia-Liang ZHANG Bin 《Pedosphere》 SCIE CAS CSCD 2005年第6期695-706,共12页
This paper introduces and illustrates the concepts of geoecological process combinations and geographical or landscape dimensions by outlining the methodology of a Sino-German cooperative project in Southeast China an... This paper introduces and illustrates the concepts of geoecological process combinations and geographical or landscape dimensions by outlining the methodology of a Sino-German cooperative project in Southeast China and presents the first results of the modelling process for the catchment scale. The project equipped a catchment in subtropical Southeast China from plot scale to catchment scale in order to study the hydrological and soll erosion processes. Distinct spatial differences in principal water and soil material fluxes were quantified. Deep drainage peaks occurred in May, June and July and even in August and November. Measurements in erosion plots as well as sedimentary deposits revealed that there was soil erosion connected with overland flow. Consistent with the results from the regular catenary variations of soil colors, textural stratification and hydrograph analysis, there was also a clear indication of interflow from measured soil moisture data. The experimental set up has the potential to further deepen the understanding of small-scale processes involved in lateral water fluxes and soil erosion. The expected results and interpretations will lead to a further integration of the collected data. In the future, to understand matter transfer in and between landscape ecological units, agricultural influence on nutrient status and flux data will be incorporated. 展开更多
关键词 CATCHMENT geoecological process combination landscape ecology soil erosion
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Impact of Global Warming on Water Resource in Arid Area of Northwest China 被引量:4
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作者 LU Aigang DING Yongjian +2 位作者 PANG Hongxi YUAN Lingling HE Yuanqing 《Journal of Mountain Science》 SCIE CSCD 2005年第4期313-318,共6页
As the unprecedented global warming is under way, the glacier retreat is getting more and more serious. In the inland arid area of Northwest China, due to very scarce precipitation, where there is water, there are oas... As the unprecedented global warming is under way, the glacier retreat is getting more and more serious. In the inland arid area of Northwest China, due to very scarce precipitation, where there is water, there are oases. And the glacier melt water amounts to 22 % of the total direct supply of the inland river water and is of crucial importance to the survival and development of the oases. In this paper, using both the observed data and the previous research achievements of the glaciers in the inland valley of Northwest China where the oasis depending on the glacier is the only location suitable for human living, the authors describe the glacier retreat trend over the past half century, focusing on discussing the possible impact of the glacier retreat on the melt water runoff that is almost the only water resource efficient to nourish the oases. The authors find that even with increasing amount of water from the glacier with global warming, the water shortage is getting more and more serious and the environment is under a degrading way due to the accelerating economical development. The water shortage is bound to be more serious if the glacier retreat keeps on, especially after the glacier melt water is over its top for the degradedglacier scale. So suggestions are stressed in the end that a new water-saving pattern should be adopted in the area for a sustainable development due to the warming-up induced continuous glacier retreat. 展开更多
关键词 Global warming glacier retreat arid area water shortage sustainable development
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Trends in extreme high temperature at different altitudes of Southwest China during 1961–2014 被引量:5
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作者 XUE Yuting CHEN Quanliang +1 位作者 ZHANG Jiayu HUANG Ping 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第5期417-425,共9页
This study analyzed the trends in extreme high temperature in Southwest China based on the observed daily maximum temperature and average temperature data from 410 Chinese stations recently released by the China Meteo... This study analyzed the trends in extreme high temperature in Southwest China based on the observed daily maximum temperature and average temperature data from 410 Chinese stations recently released by the China Meteorological Administration.The authors found that the trends in extreme high temperature at different altitudes of Southwest China exhibit staged variations during a recent 50-year period(1961–2014).The trends in mean temperature and maximum temperature also exhibit phase variation.All temperature-related variables increase gently during the period 1975–94,whereas they increase dramatically during the recent period of 1995–2014,with a rate that is approximately two to ten times more than that during 1975–94.In addition,the trends in mean temperature,maximum temperature,and the frequency of extreme high temperature in the low altitudes transit from negative to positive in the two periods,while they increase dramatically in the mid-and high-altitude areas during 1995–2014,the well-known global warming hiatus period.In particular,the maximum temperature increases much faster than that of average temperature.This result implies that the regional temperature trend could be apparently different from the global mean temperature change. 展开更多
关键词 Southwest China extreme high temperature trend change ALTITUDE
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Livelihood changes and evolution of upland ethnic communities driven by tourism:a case study in Guizhou Province,southwest China 被引量:12
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作者 LI Ya-juan VV Hu +2 位作者 CHEN Tian HU Jing CUI Hai-yang 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1313-1332,共20页
As an effective livelihood approach to alleviate poverty without rural population migration, ethnic tourism has become the primary choice of economic development in ethnic areas worldwide in addition to traditional li... As an effective livelihood approach to alleviate poverty without rural population migration, ethnic tourism has become the primary choice of economic development in ethnic areas worldwide in addition to traditional livelihood approaches. This article applies the theories of livelihood to study the community evolution driven by tourism livelihood and examine three mountainous tourism communities in different stages of tourist area life cycle. Drawing on the methods of GIS spatial analysis, semi-structured interviews and questionnaires, this article proposes a sustainable livelihood framework for ethnic tourism to explore the evolution of ethnic tourism communities by identifying changes in livelihood assets(natural, financial, social, cultural and human capitals) in the process of tourism development. The results show that the development of ethnic tourism has led to changes in the increase of building land, and the diversification of land use functions with a trend of shifting from meeting local villagers' living needs to satisfying tourists, income composition and uneven distribution of tourism income spatially. Ethnic tourism also led to the deterioration of traditional social management structure, collapse of neighboring relationship, the over- commercialization and staged authenticity of ethnic culture, as well as the gradual vanish of agricultural knowledge with a trend of increasing modern business knowledge and higher education. In addition, these changes, involving livelihood assets from natural, economic, human, social and cultural aspects are interrelated and interactive, which form new evolution characters of ethnic community. This study reveals the conflicts over livelihood approaches which have formed new vulnerabilities to impact on sustainable evolution of ethnic communities. This research provides implications for achieving the sustainable development of ethnic communities with the driving force of tourism livelihood. 展开更多
关键词 Community evolution Tourism livelihood Livelihood assets Ethnic tourism Guizhou
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Red Ratings for Loess-Paleosol Sequences on China’s Loess Plateau and Their Paleo-Climatic Implications 被引量:5
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作者 HUXue-Feng LUHua-Yu +2 位作者 XUQi DONGLi-Jing HUXing 《Pedosphere》 SCIE CAS CSCD 2004年第4期433-440,共8页
Comparisons of red ratings (RR) with Fe_d, Fe_d/Fet, clay content, andmagnetic susceptibility (x) of two loess-paleosol sequences at Luochuan and Lingtai on China's LoessPlateau were conducted to study the possibl... Comparisons of red ratings (RR) with Fe_d, Fe_d/Fet, clay content, andmagnetic susceptibility (x) of two loess-paleosol sequences at Luochuan and Lingtai on China's LoessPlateau were conducted to study the possible relationship between RR and pedogenic degrees of thetwo loess-paleosol sequences, and to discuss whether the RR could become new paleo-climaticindicators. Results showed that the RR of the two loess-paleosol sequences had positive, highlysignificant (P < 0.01) correlations with: 1) citrate-bicarbonate-dithionite (CBD) extracted iron(Fe_d), 2) ratios of CBD extracted iron to total iron (Fe_d/Fet), 3) clay (< 2 mum), and 4) magneticsusceptibility (x). This suggested that the RR of these loess-paleosol sequences could indicatedegreesof loess weathering and pedogenesis and were potential paleo-climatic proxies. The strongcorrelations of RR to Fe_d and x also implied that during pedogenic processes, pedogenic hematite inloess and paleosols were closely related to the amount of total secondary iron oxides and pedogenicferrimagnetic minerals (predominantly maghemite). 展开更多
关键词 HEMATITE loess-paleosol sequences Loess Plateau magnetic susceptibility red ratings
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The Influence of El Ni?o on MJO over the Equatorial Pacific 被引量:4
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作者 CHEN Xiong LI Chongyin TAN Yanke 《Journal of Ocean University of China》 SCIE CAS 2015年第1期1-8,共8页
In this paper, the influence of E1 Nino event on the Madden-Julian Oscillation (MJO) over the equatorial Pacific is stud- ied by using reanalysis data and relevant numerical simulation results. It is clearly shown t... In this paper, the influence of E1 Nino event on the Madden-Julian Oscillation (MJO) over the equatorial Pacific is stud- ied by using reanalysis data and relevant numerical simulation results. It is clearly shown that E1 Nino can reduce the intensity of MJO. The kinetic energy of MJO over the equatorial Pacific is stronger before the occurrence of the E1 Nino event, but it is reduced rapidly after E1 v event outbreak, and the weakened MJO even can continue to the next summer. The convection over the cen- tral-western Pacific is weakened in E1 Nino winter. The positive anomalous OLR over the central-western Pacific has opposite variation in E1 Nino winter comparing to the non-ENSO cases. The vertical structure of MJO also affected by E1 Nino event, so the opposite direction features of the geopotential height and the zonal wind in upper and lower level troposphere for the MJO are not remarkable in the E1 Nino winter and tend to be barotropic features. El Nino event also has an influence on the eastward propa- gation of the MJO too. During E1 Nino winter, the eastward propagation of the MJO is not so regular and unanimous and there exists some eastward propagation, which is faster than that in non-ENSO case. Dynamic analyses suggest that positive SSTA (El Nino case) affects the atmospheric thickness over the equatorial Pacific and then the excited atmospheric wave-CISK mode is weakened, so that the intensity of MJO is reduced; the combining of the barotropic unstable mode in the atmosphere excited by external forcing (SSTA) and the original MJO may be an important reason for the MJO vertical structure tending to be barotropic during the E1 Nino. 展开更多
关键词 E1 Nino MJO INTENSITY vertical structure eastward propagation
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Can Artificial Climate Trends in Global Reanalysis be Reduced by Dynamical Downscaling:A Case Study of China 被引量:2
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作者 ZHAO Tian-Bao ZHAO De-Ming 《Atmospheric and Oceanic Science Letters》 2011年第1期30-35,共6页
In this study, the ability of dynamical downscaling for reduction of artificial climate trends in global reanalysis is tested in China. Dynamical downscaling is performed using a 60-km horizontal resolution Regional I... In this study, the ability of dynamical downscaling for reduction of artificial climate trends in global reanalysis is tested in China. Dynamical downscaling is performed using a 60-km horizontal resolution Regional Integrated Environmental Model System (RIEMS) forced by the NCEP-Department of Energy (DOE) reanalysis II (NCEP-2). The results show that this regional climate model (RCM) can not only produce dynamically consis- tent fine scale fields of atmosphere and land surface in the regional domain, but it also has the ability to minimize artificial climate trends existing in the global reanalysis to a certain extent. As compared to the observed 2-meter temperature anomaly averaged across China, our model can simulate the observed inter-annual variation and variability as well as reduce artificial climate trends in the reanalysis by approximately 0.10℃ decade-1 from 1980 to 2007. The RIEMS can effectively reduce artificial trends in global reanalysis for areas in western China, especially for regions with high altitude mountains and deserts, as well as introduce some new spurious changes in other local regions. The model simulations overesti- mated observed winter trends for most areas in eastern China with the exception of the Tibetan Plateau, and it greatly overestimated observed summer trends in the Si- chuan Basin located in southwest China. This implies that the dynamical downscaling of RCM for long-term trends has certain seasonal and regional dependencies due to imperfect physical processes and parameterizations. 展开更多
关键词 dynamical downscaling artificial climate trends global reanalysis
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Mantle plume activity and melting conditions: Evidence from olivines in picritic-komatiitic rocks from the Emeishan Large Igneous Province, southwestern China 被引量:10
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作者 Zhaochong Zhang Jingwen Mao +2 位作者 Fusheng Wang Yanli Hao John J. Mahoney 《Episodes》 SCIE 2005年第3期171-176,共6页
Olivine phenocryst compositions and whole-rock chemical compositions are used to identify primitive picrite basalts from the early part of flood basalt successions in the western part of the Emeishan large igneous pro... Olivine phenocryst compositions and whole-rock chemical compositions are used to identify primitive picrite basalts from the early part of flood basalt successions in the western part of the Emeishan large igneous province (ELIP), southwestern China. The Fo contents of olivine phenocrysts of komatiites with MgO-21.79 wt% range from 85.2% to 91.4%. The composition of unerupted parental melts is calculated from the compositions of the most Fo-rich olivine phenocrysts. These melts had -22 wt% MgO, and originated in mantle with a potential temperature of -1600℃ and at about 4.2 GPa pressure, supporting the conclusion that the generation of ELIP can be attributed to melting of a plume head beginning at -138 km depth. 展开更多
关键词 PERMIAN-TRIASSIC BOUNDARY FLOOD BASALTS SW CHINA GEOCHEMICALCONSTRAINTS HAWAIIAN VOLCANISM PERIDOTITE KLB-1 ICELAND PLUME HIGH-MG MAGMAS LAVAS
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Improving S/N ratio for pre-stack seismic data from western China 被引量:2
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作者 Guo Ping Zhang Wenpo Gao Yan Zhao Jun Gao Shumei 《Applied Geophysics》 SCIE CSCD 2007年第3期207-213,共7页
The seismic data from western China is very noisy. Two main reasons are static corrections and low S/N ratio problems. By seismic data processing and study these problems have been effectively solved by iterating the ... The seismic data from western China is very noisy. Two main reasons are static corrections and low S/N ratio problems. By seismic data processing and study these problems have been effectively solved by iterating the static corrections and improving the S/N ratio for pre-stack seismic data. Suppression and elimination of various other distortions has been implemented as well. Due to the fact that the S/N ratio is improved, the resolution of the seismic data is also improved. 展开更多
关键词 Static correction low S/N ratio RESOLUTION
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Modeling of the Second Indirect Effect of Anthropogenic Aerosols in East Asia 被引量:2
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作者 WU Peng-Ping HAN Zhi-Wei 《Atmospheric and Oceanic Science Letters》 2011年第6期316-323,共8页
This study investigated the second indirect climatic effect of anthropogenic aerosols,including sulfate,organic carbon(OC) ,and black carbon(BC) ,over East Asia.The seasonal variation of the climatic response to the s... This study investigated the second indirect climatic effect of anthropogenic aerosols,including sulfate,organic carbon(OC) ,and black carbon(BC) ,over East Asia.The seasonal variation of the climatic response to the second indirect effect was also characterized.The simulation period for this study was 2006.Due to a decrease in autoconversion rate from cloud water to rain as a result of aerosols,the cloud liquid water path(LWP) ,and radiative flux(RF) at the top of the atmosphere(TOA) changed dramatically,increasing by 14.3 g m-2 and decreasing by-4.1 W m-2 in terms of domain and annual average.Both LWP and RF changed most in autumn. There were strong decreases in ground temperature in Southwest China,the middle reaches of the Yangtze River in spring and autumn,while maximum cooling of up to-1.5 K occurred in the Chongqing district.The regional and annual mean change in ground temperature reached-0.2 K over eastern China.In all seasons except summer,precipitation generally decreased in most areas north of the Yangtze River,whereas precipitation changed little in South China.Precipitation changed most in summer,with alternating bands of increasing(~40 mm) and decreasing(~40 mm) precipitation appearing in eastern China.Precipitation decreased by 1.5-40 mm over large areas of Northeast China and the Huabei Plain.The domain and annual mean change in precipitation was approximately-0.3 mm over eastern China.The maximum reduction in precipitation occurred in summer,with mean absolute and relative changes of-1.2 mm and-3.8%over eastern China.This study revealed considerable climate responses to the second indirect effect of aerosols over specific regions of China. 展开更多
关键词 AEROSOLS second indirect effect autoconversion liquid water path model simulation
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Glacial Runoff Likely Reached Peak in the Mountainous Areas of the Shiyang River Basin,China 被引量:13
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作者 ZHANG Shi-qiang GAO Xin Zhang Xiao-wen 《Journal of Mountain Science》 SCIE CSCD 2015年第2期382-395,共14页
Glacier runoff in mountain areas of the Shiyang River Basin(SRB), Qilian Mountain, western China is important for the river and water supply downstream. Small glaciers with area of less than 1km2 are dominant(87%) in ... Glacier runoff in mountain areas of the Shiyang River Basin(SRB), Qilian Mountain, western China is important for the river and water supply downstream. Small glaciers with area of less than 1km2 are dominant(87%) in the SRB. A modified monthly degree-day model was applied to quantify the glacier mass balance, area, and changes in glacier runoff in the SRB during 1961–2050. The comparison between the simulated and observed snow line altitude, annual glacier runoff, and mass balance from1961 to 2008 suggests that the degree-day model may be used to analyze the long-term change of glacier mass balance and runoff in the SRB. The glacier accumulation shows a significant(p<0.01) decreasing trend of-0.830 mm a-1. The mass balance also shows a significant(p<0.01) decreasing trend of-5.521 mm a-1. The glacier total runoff has significantly(p<0.05)increased by 0.079 × 105 m3 from 1961 to 2008. The monthly precipitation and air temperature are projected to significant(p<0.005) increase during2015 to 2050 under three different scenarios. The ablation is projected to significant(p<0.001) increase,while the accumulation has no significant(p=0.05)trend. The mass balance is projected to decrease, theglacier area is projected to decrease, and the glacier runoff depth is projected to increase. However, the glacier total runoff is projected to decrease. These results indicate that the glacier total runoff over glacier areas observed in 1970 reached its peak in the 2000 s. This will exacerbate the contradiction between water supply and downstream water demands in the SRB. 展开更多
关键词 Climate change Mass balance Glacial runoff Glacier area Shiyang River Basin
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