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融入中华优秀传统文化的地理教学实践——以人教版“西北地区”内容为例
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作者 张燚 《中学课程资源》 2023年第9期28-34,共7页
地理教材是中华优秀传统文化传播的重要载体,在地理课堂中渗透中华优秀传统文化可以促进地理核心素养落地,实现地理课堂教学的育人功能。以“西北地区”为例,教师通过对课标、教材、结构和学情的分析,创设教学情境,以古诗为主线串联整... 地理教材是中华优秀传统文化传播的重要载体,在地理课堂中渗透中华优秀传统文化可以促进地理核心素养落地,实现地理课堂教学的育人功能。以“西北地区”为例,教师通过对课标、教材、结构和学情的分析,创设教学情境,以古诗为主线串联整个课堂,重新整合教材内容,有效构建“西北地理位置与自然地理特征”“自然条件对西北经济发展的影响”知识体系,在地理教学实践中有效融入中华优秀传统文化,积极发挥文化渗透功能。 展开更多
关键词 传统文化 地理教学 “西北地区”
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“西北地区”一节插图教学设计
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作者 黄承波 《地理教学》 2002年第4期27-27,共1页
关键词 “西北地区” 插图 初中地理 分布图 景观图 教学设计
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“西北地区”一节教学设计
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作者 崔风华 《地理教学》 2003年第4期35-35,共1页
一、多媒体情景导人,激发求知兴趣多媒体播放VCD《蒙古人》,鼠标切换图片"维族舞",设问:"这是四大地区中的哪一个地区?"鼠标点击"西北地区位置和地形图",请学生指图简介西北地区的位置范围、省区、民族。
关键词 “西北地区” 教学设计 中学地理 探究式学习 自然条件
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Impact of Dry Warming on Economic and Characteristic Crop and Coping Technology in Northwest of China 被引量:4
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作者 邓振镛 倾继祖 +3 位作者 杨启国 宁惠芳 黄蕾诺 徐金强 《Agricultural Science & Technology》 CAS 2010年第4期124-129,共6页
Based on the state of characteristics of dry warming of modern climate changing,the response of growth,output and quality of main economic crops such as cotton,flax and winter rape and characteristic crop such as vini... Based on the state of characteristics of dry warming of modern climate changing,the response of growth,output and quality of main economic crops such as cotton,flax and winter rape and characteristic crop such as vinifera and apple were discussed.The coping technology for climate changing and measurements for serving the agricultural were provided. 展开更多
关键词 NORTHWEST Dry warming Economic crop Characteristic crop Influence Coping technology
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The Comparison of Contents of Malondialdehyde and Proline in the Area of Karst Area in Northweastern Guangxi Province 被引量:6
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作者 覃勇荣 农艳春 +1 位作者 黄江滨 潘振兴 《Agricultural Science & Technology》 CAS 2011年第4期469-473,575,共6页
[Objective] To select excellent pioneer species of better ecological and economical comprehensive benefits from the common rock hill plants in Karst area in northwestern Guangxi Province.[Method] Determine the content... [Objective] To select excellent pioneer species of better ecological and economical comprehensive benefits from the common rock hill plants in Karst area in northwestern Guangxi Province.[Method] Determine the contents of malondialdehyde and proline in leaves of 65 strains of plants by thiobarbituric acid method and sultosalicylic acid method,analyze the relevance of the contents of malondialdehyde and proline by mathematics statistics and analyze the 65 kinds of rock hill plants by clustering [Result] The contents of malondialdehyde and proline are 0.005 2-0.038 1 μmol/g.There are comparably significant differences in the contents of malondialdehyde in different plants;The determination of proline contents in plant's leaves are 4.347-374.956 μg/ml.There are also significant differences in proline of different leaves of rock hill plants.The contents of malondialdehyde and proline can be used as a reference point in selecting pioneer plants in Karst area.But when we select the pioneer plants,not only the biological characters of the species themselves should be taken into consideration,but also the differences of Karst area environment,ecological and biological benefits and the reasonable distribution of species.[Conclusion] Pistacia chinensis,Zenia insignis,Acacia confusa,Itoa orientalis and Sophora japonica can be used as the first choices of excellent pioneer plants in Karst area in northwestern area which comparably consists with the real situation of afforestation of rock hills and recovery of plants in Guangxi. 展开更多
关键词 Northwestern of Guangxi Karst area Rock hills plants MALONDIALDEHYDE PROLINE
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Application of Prediction Techniques in Carbonate Karst Reservoir in Tarim Basin 被引量:5
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作者 陈广坡 撒利明 +2 位作者 韩剑发 管文胜 Guan Wensheng 《Applied Geophysics》 SCIE CSCD 2005年第2期111-118,F0003,共9页
Carbonate karst reservoir is the emphases of Tarim's carbonate exploration. However, it is buried at a large depth, which results in Weak seismic reflection signal and low S/N ratio. In addition, the karst reservoir ... Carbonate karst reservoir is the emphases of Tarim's carbonate exploration. However, it is buried at a large depth, which results in Weak seismic reflection signal and low S/N ratio. In addition, the karst reservoir contains great heterogeneity, so reservoir prediction is very difficult. Through many years of research and exploration, we have established a suite of comprehensive evaluation technology for carbonate karst reservoir using geophysical characteristics and a geological concept model, including a technique for reconstructing the paleogeomorphology of buried hills based on a sequence framework, seismic description of the karst reservoir, and strain variant analysis for fracture estimation. The evaluation technology has been successfully applied in the Tabei and Tazhong areas, and commercial production of oil and gas has been achieved. We show the application of this technology in the Lunguxi area in North Tarim in this paper. 展开更多
关键词 Tarim basin karst reservoir seismic response reservoir prediction and comprehensive evaluation
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问题解决式教学在初中地理教学中的实践 被引量:3
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作者 刘楠 李文胜 《基础教育课程》 北大核心 2019年第6期61-63,共3页
问题解决能力是形成"创新精神与实践能力"的关键,也是一种重要的地理素养。本文以"西北地区开发和保护"一课为例,通过"创设情境—激发探究""设疑问难—探究讨论""矛盾生成—思维进阶"... 问题解决能力是形成"创新精神与实践能力"的关键,也是一种重要的地理素养。本文以"西北地区开发和保护"一课为例,通过"创设情境—激发探究""设疑问难—探究讨论""矛盾生成—思维进阶"几个教学环节的问题设置,探究问题解决式教学在地理课堂教学中的应用。 展开更多
关键词 解决问题式教学 初中地理教学 “西北地区开发和保护” 地理探究
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Analysis on Ecological Risk in Northwest China
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作者 刘引鸽 《Agricultural Science & Technology》 CAS 2014年第12期2230-2235,共6页
Based on scenario analysis method, assuming different economic develop- ment policies, and AHP method, the ecological indicators and risk prediction models were established. The trends of ecological risk in the northw... Based on scenario analysis method, assuming different economic develop- ment policies, and AHP method, the ecological indicators and risk prediction models were established. The trends of ecological risk in the northwest region were ana- lyzed. The results showed that: in the northwest, the potential ecological risks of the population economy, water resources, and land resources and natural disasters still existed. However, the environment and respond to ecological risks were decreasing. Therefore, a regional balanced development measures had been taken to curb the western trend of ecological deterioration. So that socio-economic development, re- sources, environment, and economy were expected to a virtuous cycle, and the eco- logical risks would be reduced. This study provides the basis for land and water use planning and environmental protection of government decision-making and management. 展开更多
关键词 Ecological Risk Scenario Analysis TREND NORTHWEST
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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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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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Promoter hypermethylation of CDH1, FHIT, MTAP and PLAGL1 in gastric adenocarcinoma in individuals from Northern Brazil 被引量:24
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作者 Mariana Ferreira Leal Eleonidas Moura Lima +5 位作者 Patrícia Natália Oliveira Silva Paulo Pimentel Assumpo Danielle Queiroz Calcagno Spencer Luiz Marques Payo Rommel Rodríguez Burbano Marília de Arruda Cardoso Smith 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第18期2568-2574,共7页
AIM:To evaluate the methylation status of CDH1, FHIT, MTAP and PLAGL1 promoters and the association of these findings with clinico-pathological characteristics.METHODS: Methylation-specific PCR (MSP) assay was per... AIM:To evaluate the methylation status of CDH1, FHIT, MTAP and PLAGL1 promoters and the association of these findings with clinico-pathological characteristics.METHODS: Methylation-specific PCR (MSP) assay was performed in 13 nonneoplastic gastric adenocarcinorna, 30 intestinal-type gastric adenocarcinorna and 35 diffuse-type gastric adenocarcinorna samples from individuals in Northern Brazil. Statistical analyses were performed using the chi-square or Fisher's exact test to assess associations between rnethylation status and clinico-pathological characteristics.RESULTS: Hypermethylation frequencies of CDH1, FHIT, MTAPand PLAGL1 promoter were 98.7%, 53.9%, 23.1% and 29.5%, respectively. Hyperrnethylation of three or four genes revealed a significant association with diffuse-type gastric cancer compared with nonneoplastic cancer. A higher hyperrnethylation frequency was significantly associated with H pylori infection in gastric cancers, especially with diffuse-type. Cancer samples without lymph node metastasis showed a higher FHIT hypermethylation frequency. MTAP hypermethylation was associated with H pylori in gastric cancer samples, as well as with diffuse-type compared with intestinal-type. In diffuse-type, MTAP hypermethylation was associated with female gender.CONCLUSION: Our findings show differential gene methylation in tumoral tissue, which allows us to conclude that hypermethylation is associated with gastric carcinogenesis. MTAP promoter hypermethylation can be characterized as a marker of diffuse-type gastric cancer, especially in women and may help in diagnosis, prognosis and therapies. The H pylori infectious agent was present in 44.9% of the samples. This infection may be correlated with the carcinogenic process through the gene promoter hypermethylation, especially the MTAP promoter in diffuse-type. A higher H pylori infection in diffuse-type may be due to greater genetic predisposition. 展开更多
关键词 Gastric adenocarcinoma DNA hypermethylation CDH1 FHIT MTAP PLAGL1
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Isotopic composition of precipitation over Arid Northwestern China and its implications for the water vapor origin 被引量:20
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作者 柳鉴容 宋献方 +3 位作者 孙晓敏 袁国富 刘鑫 王仕琴 《Journal of Geographical Sciences》 SCIE CSCD 2009年第2期164-174,共11页
In order to reveal the characteristics and climatic controls on the stable isotopic composition of precipitation over Arid Northwestern China, eight stations have been selected from Chinese Network of Isotopes in Prec... In order to reveal the characteristics and climatic controls on the stable isotopic composition of precipitation over Arid Northwestern China, eight stations have been selected from Chinese Network of Isotopes in Precipitation(CHNIP).During the year 2005 and 2006, monthly precipitation samples have been collected and analyzed for the composition of δD and δ18O.The established local meteoric water line δD=7.42δ18O+1.38, based on the 95 obtained monthly composite samples, could be treated as isotopic input function across the region.The deviations of slope and intercept from the Global Meteoric Water Line indicated the specific regional meteorological conditions.The monthly δ18O values were characterized by a positive correlation with surface air temperature(δ18O(‰) =0.33 T(℃)-13.12).The amount effect visualized during summer period(δ18O(‰) =-0.04P(mm)-3.44) though not appeared at a whole yearly-scale.Spatial distributions of δ18O have properly portrayed the atmospheric circulation background in each month over Arid Northwestern China.The quan-titative simulation of δ18O, which involved a Rayleigh fractionation and a kinetic fractionation, demonstrated that the latter one was the dominating function of condensation of raindrops.Furthermore, the raindrop suffered a re-evaporation during falling processes, and the precipitation vapor might have been mixed with a quantity of local recycled water vapor.Multiple linear regression equations and a δ18O-T relation have been gained by using meteorological parameters and δ18O data to evaluate physical controls on the long-term data.The established δ18O-T relation, which has been based on the present-day precipitation, could be considered as a first step of quantitatively reconstructing the historical environmental climate. 展开更多
关键词 Arid Northwestern China (ANC) Δ^18O PRECIPITATION water vapor origin
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Shrub Communities and Environmental Variables Responsible for Species Distribution Patterns in an Alpine Zone of the Qilian Mountains, Northwest China 被引量:8
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作者 HUO Hong FENG Qi SU Yong-hong 《Journal of Mountain Science》 SCIE CSCD 2015年第1期166-176,共11页
Understanding the factors that drive variation in species distribution is a central theme of ecological research. Although several studies focused on alpine vegetation, few efforts have been made to identify the envir... Understanding the factors that drive variation in species distribution is a central theme of ecological research. Although several studies focused on alpine vegetation, few efforts have been made to identify the environmental factors that are responsible for the variations in species composition and richness of alpine shrublands using numerical methods. In the present study, we investigated vegetation and associated environmental variables from 45 sample plots in the middle Qilian Mountains of the northwestern China to classify different community types and to elucidate the species- environment relationships. We also estimated the relative contributions of topography and site conditions to spatial distribution patterns of the shrub communities using the variation partitioning. The results showed that four shrub community types were identified and striking differences in fioristic composition were found among them. Species composition greatly depended on elevation, slope, shrub cover, soil pH and organic carbon. The important determinants of species richness were soil bulk density and slope. No significant differences in species richness were detected among the community types. Topography and site conditions had almost equal effects on compositional variation. Nonetheless,a large amount of the variation in species composition remained unexplained. 展开更多
关键词 Alpine shrublands Floristic composition Cluster analysis Canonical Correspondence Analysis(CCA) Variation partitioning Species composition Species richness
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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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Identification and Evolution of Groundwater Chemistry in the Ejin Sub-Basin of the Heihe River, Northwest China 被引量:5
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作者 SU Yong-Hong FENG Qi +2 位作者 ZHU Gao-Feng SI Jian-Hua ZHANG Yan-Wu 《Pedosphere》 SCIE CAS CSCD 2007年第3期331-342,共12页
Hydro-chemical characteristics of groundwater and their changes as affected by human activities were studied in the Ejin Sub-Basin of the Inner Mongolia Autonomous Region, China, to understand the groundwater evolutio... Hydro-chemical characteristics of groundwater and their changes as affected by human activities were studied in the Ejin Sub-Basin of the Inner Mongolia Autonomous Region, China, to understand the groundwater evolution, to identify the predominant geochemical processes taking place along the horizontal groundwater flow path, and to characterize anthropogenic factors affecting the groundwater environment based on previous data. The concentrations of major ions and total dissolved solids (TDS) in the groundwater showed a great variation, with 62.5% of the samples being brackish (TDS ≥ 1 000 mg L^-l). The groundwater system showed a gradual hydro-chemical zonation composed of Na^+ -HCO3^-, Na^+ -Mg^2+ -SO4 ^2 -Cl^-, and Na^+ -Cl^-. The relationships among the dissolved species allowed identification of the origin of solutes and the processes that generated the observed water compositions. The dissolution of halite, dolomite, and 2- gypsum explained, in part, the presence of Na^+, K^+, Cl^-, SO^4 , and Ca^2+, but other processes, such as mixing, Na^+ exchange for Ca^2+ and Mg^2+, and calcite precipitation also contributed to the composition of water. Human activity, in particular large-scale water resources development associated with dramatic population growth in the last 50 years, has led to tremendous changes in the groundwater regime, which reflected in surface water runoff change, decline of groundwater table and degeneration of surface water and groundwater quality. Solving these largely anthropogenic problems requires concerted, massive and long-term efforts. 展开更多
关键词 Ejin Sub-Basin groundwater quality Heihe River human impact water resources development
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Impacts of Global Warming Perturbation on Water Resources in Arid Zone: Case Study of Kaidu River Basin in Northwest China 被引量:6
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作者 MUPENZI Jean de la Paix 《Journal of Mountain Science》 SCIE CSCD 2011年第5期704-710,共7页
The main goal of this study was to assess the long-term impacts of global warming perturbation on water resources of the Kaidu River Basin in Northwest China. Temperature, precipitation and hydrology data during the p... The main goal of this study was to assess the long-term impacts of global warming perturbation on water resources of the Kaidu River Basin in Northwest China. Temperature, precipitation and hydrology data during the past 29 years from 1979 to 2007 were collected and analyzed using parametric and non-parametric methods, the connection between temperature and precipitation by the combination of grey correlation analysis method and the hypothesis testing for trend of climate change. The results show a high increase in temperature in the study area as well as an extreme and highly variable hydrological regime in this region, where flash floods can exceed the total runoff from a sequence of years. These variations may be due to the geographical location of the Kaidu River Basin in arid zone. It also reveals that precipitation has a much greater impact on stream flow than that of temperature. The development of new approaches was proposed as responses to climate change in this arid region. 展开更多
关键词 Global warming Kaidu River TEMPERATURE Precipitations Stream flow
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Geomorphological Evolution Revealed by Aeolian Sedimentary Structure in Badain Jaran Desert on Alxa Plateau, Northwest China 被引量:7
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作者 BAI Yang WANG Nai'ang +1 位作者 LIAO Kongtai Patrick KLENK 《Chinese Geographical Science》 SCIE CSCD 2011年第3期267-278,共12页
The Badain Jaran Desert,located in the Alxa Plateau,Northwest China,features mega-dunes and a unique dune-lake alternation landscape.This paper presented the aeolian sediment structures of three representative dunes i... The Badain Jaran Desert,located in the Alxa Plateau,Northwest China,features mega-dunes and a unique dune-lake alternation landscape.This paper presented the aeolian sediment structures of three representative dunes in the Badain Jaran Desert using ground-penetrating radar (GPR).We processed and analyzed the GPR data and investigated the feasibility of using integrated GPR and sedimentological data to reconstruct dunes structure,sedimentary environment and geomorphological evolution.The results show that the internal structures of star dune and transverse dune represent various stages of mega-dune evolution: the main deposition processes of mega-dune are similar to those of transverse dunes but have a more complicated mechanism of sand transport and deposition because of the superimposition of dunes;the upper section of the mega-dune has a structure similar to that of star dune,with vertical aggradations on top.Diffraction hyperbolae in the GPR profile indicates that the presence of ancient dunes characterized by calcareous cementation layers is involved in the maintenance of mega-dunes,and water levels,shown by continuous,sub-horizontal GPR reflections,are supposed to be closely related to mega-dunes and the interdune lakes.Outcrop of wet sand and horizontal stratifications on the GPR image indicate moisture potentials with different levels inside mega-dunes.The multiplex geomorphology in the Badain Jaran Desert is the result of global climatic undulation,the unique geographical location,the geological structural features,etc. 展开更多
关键词 Badain Jaran Desert Ground-Penetrating Radar (GPR) mega-dunes sedimentary structure geomor- phological evolution
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Difference in the Interdecadal Variability of Spring and Summer Sensible Heat Fluxes over Northwest China 被引量:9
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作者 ZHOU Lian-Tong 《Atmospheric and Oceanic Science Letters》 2009年第2期119-123,共5页
The present study investigates the difference in interdecadal variability of the spring and summer sensible heat fluxes over Northwest China by using station observations from 1960 to 2000. It was found that the sprin... The present study investigates the difference in interdecadal variability of the spring and summer sensible heat fluxes over Northwest China by using station observations from 1960 to 2000. It was found that the spring sensible heat flux over Northwest China was greater during the period from the late 1970s to the 1990s than during the period from the 1960s to the mid-1970s. The summer sensible heat flux was smaller in the late 1980s through the 1990s than it was in the 1970s through the early 1980s. Both the spring and summer land-air temperature differences over Northwest China displayed an obvious interdecadal increase in the late 1970s. Both the spring and summer surface wind speeds experienced an obvious interdecadal weakening in the late 1970s. The change in the surface wind speed played a more important role in the interdecadal variations in sensible heat flux during the summer, whereas the change in the land-air temperature difference was more important for the interdecadal variations in sensible heat flux in the spring. This difference was related to seasonal changes in the mean land-air temperature difference and the surface wind speed. Further analysis indicated that the increase in the spring land surface temperature in Northwest China was related to an increase in surface net radiation. 展开更多
关键词 sensible heat flux land-air temperature difference surface wind speed surface net radiation
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Land Use Changes of an Aeolian-Loessial Soil Area in Northwest China: Implications for Ecological Restoration 被引量:6
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作者 CHEN Yu-Fu LIU Yan-Sui +2 位作者 WANG Jing YAN Jian-Ping GUO Xu-Dong 《Pedosphere》 SCIE CAS CSCD 2009年第3期356-361,共6页
China has experienced dramatic land use changes over recent decades, with marked environmental and socio-economic consequences. Hengshan County, located in the aeolian-loessial area of Northwest China, was investigate... China has experienced dramatic land use changes over recent decades, with marked environmental and socio-economic consequences. Hengshan County, located in the aeolian-loessial area of Northwest China, was investigated to illustrate land use changes and their implications for environmental and long-term rural economic development. The farmland in Hengshan County significantly decreased during 1990–2003, whereas forest land and grassland increased. The conversion rates of farmland, orchard land, forest land and construction land varied markedly among different periods: 1990–1995, 1995–2000 and 2000–2003. Conversion of orchard land, grassland and construction land was dominant in 1990–1995, whereas the conversion of farmland to forest land mainly occurred in 2000–2003. The results suggested a profound transition in institutional policy and political economy of land management, including implementation of integrated soil erosion control projects, adoption of a market-oriented economy and the ‘Grain-for-Green’ policy, during this period in China. To achieve long-term sustainable land use in Hengshan County, efforts should aim at increasing off-farm income of rural families as well as establishing land-economizing mechanisms to promote land productivity, in addition to conservation measures. 展开更多
关键词 Hengshan County land management per capita land area POLICY sustainable land use
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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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